摘要:The concept of bifundamental figurates in spherical space is given in this paper . Using algebraic method , the metric equations in spherical space , given by Yang Lu and Zhang Jingzhong , are generalized to bifundamental figurates , and the generalized metric equations are obtained . As their primary applications , some formula involving two simplexes are given in spherical space .%提出了球面型空间中双基本图形的概念,利用代数方法建立了球面型空间中双基本图形的广义度量方程,从而推广了杨路和张景中的结果。作为初步应用,给出了球面型空间中涉及两个单形的一些有趣公式。
摘要:This article takes the domestic gateway city Zhaoqing City ,Guangdong Province as an example and selects a number of indicators to build the type of urban competitiveness evaluation index system . It uses the method of principal component analysis to analyze seven elements w hich decides the competitiveness of Zhaoqing . T he seven elements are level of economic development , industrial structure , economic extroversion , the level of social development , infrastructure construction , transportation accessibility and the concentration and diffusion capacity of city . T he results show that the city competitiveness of Zhaoqing steady rises in recent years and has strong sustainability , the economic development support system has the largest contribution to urban competitiveness , otherwise the extroverted degree contribution is smallest . Aiming at the existing problem of the city , we put forward the countermeasures and suggest how to further enhance the comprehensive competitiveness of Zhaoqing w hich can increase investment in infrastructure construction , speed up the industrial transformation and upgrading , lever “two space” , promote the construction of “big Zhaoqing”.%以国内枢纽型门户城市广东省肇庆市为例,选取若干指标,构建该类型城市竞争力评价指标体系,运用主成分分析方法分析了决定肇庆城市竞争力的经济发展水平、产业结构、经济外向度、社会发展水平、基础设施建设、交通通达性、城市集聚扩散能力7大要素。结果表明,近年来肇庆市城市竞争力处于稳步提升的发展状态,具有较强的可持续性,其中经济发展支持系统对城市竞争力贡献度最大,经济外向度贡献最小。针对城市存在的问题,就如何进一步提升肇庆枢纽型门户城市综合竞争力提出了对策建议,即加大基础设施建设投入,加快产业转型与升级,借力“两个空间”,促进“大肇庆”建设。
摘要:T his paper analyzes disparity of inbound tourism size in Xinjiang from 2000 to 2012 at three levels i.e. the w hole Xinjiang , three regions and fifteen prefectures , autonomous prefectures and cities . The methods are used such as standard deviation , coefficient of variation , location quotient , Gini coefficient and tourism market competition state . T he results show that inbound tourism in Xinjiang is developed rapidly .Absolute and relative disparity are striking and the whole disparity are still large .The development of inbound tourism of the north region in Xinjiang is far higher than the average level of Xinjiang . Inbound tourism scale disparity of the north region in Xinjiang is narrowing gradually . But the diaparity is large among prefectures , autonomous prefecture and city of the north region in Xinjiang . It's obvious for the characters of agglomeration . The development of inbound tourism of the south region in Xinjiang is far lower than the average level of Xinjiang . Inbound tourism scale disparity of south region in Xinjiang is narrowing gradually .But the disparity is still large among prefecture , autonomous prefecture and cities of the South region in Xinjiang . It's obvious for the characters of agglomeration . All in all , the development of inbound tourism of the east region in Xinjiang is lower than the average level of Xinjiang . Inbound tourism scale disparity of the east region in Xinjiang is decreasing gradually and lessening between Turpan Administrative Offices and Hami Administrative Offices in inbound tourism scale . As a whole , competitive state of destination market on international tourism in Xinjiang is good , competitive state of destination market on international tourism of the north and the east region in Xinjiang is better than terminal‐market competitive state on inbound tourism of the south region in Xinjiang .%以2000—2012年新疆入境市场的相关统计数据为基础,利用区位熵指数、绝对差异和相对差异、基尼系数等多种方法,根据全疆、3大区城和15个地州市,对入境旅游近10年来的规模差异进行分析。结果表明,新疆入境旅游发展迅速,但绝对差异和相对差异显著,总体差异仍然很大;北疆入境旅游发展远高于全疆平均水平,规模差异逐步缩小,但地州市间差异仍很大,规模集聚特征明显;南疆入境旅游发展远低于全疆平均水平,规模差异逐步缩小,但地州市间差异仍较大,规模集聚特征较明显;东疆入境旅游发展略低于全疆水平,规模差异整体上呈缩小的趋势,并且哈密地区与吐鲁番地区之间的差距正在逐渐缩小。从整体上来说,新疆入境旅游目的地发展态势良好,北疆与东疆地州市发展竞争态势比南疆地州市发展态势要好。
摘要:In order to obtain the numerical solution of fractional order variable coefficients Volterra‐Fredholm integro‐differential equation with weakly singular kernels , an operational matrix method is presented in this paper .An approximate formula which solves solution of arbitrary order weakly singular integral is given by using the definition of Legendre polynomial and some properties . And an operational matrix of fractional derivatives of Legendre polynomial is also obtained . Then the original problem of the equation is changed into a system of algebraic equation through simplifying and descreting the fractional integro‐differential equation . The convergence analysis proves that the method is convergent . The numerical examples show that the approach is effective .%为了求分数阶变系数且带有弱奇异积分核Volterra‐Fredholm积分微分方程的数值解,本文提出了Legendre多项式算子矩阵法,利用Legendre多项式的定义及其性质给出了分数阶微分算子矩阵,同时也给出了任意阶弱奇异积分的近似求积公式。通过简化所求分数阶积分微分方程,并离散化简后的方程,可将原问题转换为求代数方程组的解。收敛性分析证明了本文方法是收敛的,数值算例验证了该方法的有效性。
摘要:通过因子分析方法和ESDA相结合,从全局和局部研究了甘肃省农业现代化的空间分布特征与空间关联特征。结果表明,甘肃省县域农业现代化综合评价由农业物质装备因子和农业劳动力技术水平因子、农村社会发展水平因子、农业可持续发展4大因子所决定。甘肃省农业现代化在空间上形成了以酒泉‐嘉峪关‐张掖为代表的高‐高型集聚区和以中南部包含天水市、陇南市、甘南州、临夏州为代表的低‐低型集聚区。%From the global and local dimensions , spatial association characteristic of agricultural modernization of Gansu Province are studied by using the methods of the spatial analysis of ESDA and factor analysis in this paper . The analysis show that , the agricultural organization of Gansu Province is at a low level , while the evaluation of agricultural modernization is determined by the four main factors included agricultural equipment , the labor technology , the level of social development of rural , and the level of a sustainable agricultural development . The high‐high category of the agricultural modernization agglomeration is located in the Jiuquan‐Jiayuguan‐Zhangye of the Hexi Corridor , w hile the low‐low category is located in the Tianshui‐Longnan‐Gannan‐Linxia of the middle southern of Gansu Province .
摘要:Using the remote sensing images of Gahai area and meteorological data of Luqu county station and Gahai station , we quantitatively analyze spatial characteristics of Gahai Lake area with the support of GIS , RS technology and the method of correlation analysis . The major results can be summarized as follow s :average temperature and precipitation increase significantly , snow days and evaporation reduce significantly , the depth of permafrost becomes shallow in Gahai area . Lake area increased significantly , especially the increase rate is faster in the past 10 years . T he effects of average temperature , precipitation ,evaporation and permafrost depth on the change of lake area are the most significant . The average temperature ,precipitation ,extreme low temperatures and precipitation are positive correlation to the lake area ;evaporation and maximum depth of permafrost in January and February are negative correlation to the lake area . Gahai Lake expansion is the result of rising temperature , increasing precipitation , reducing evaporation and degradation of permafrost .%利用尕海地区的遥感影像资料与碌曲县站、尕海站的气象资料,综合使用RS ,GIS技术以及统计分析的方法对尕海湖面积变化的空间特征做了定量分析。结果表明,尕海湖区年平均气温、降水量显著增加,积雪天数、蒸发量显著减少,冻土深度有所变浅;湖泊面积显著增加,特别近10年增加速率加快;湖面变化受年均气温、极端低温、蒸发量、降水量、1,2月最大冻土深度的影响最为显著。年平均气温、极端低温、降水量与湖泊面积呈正相关关系;蒸发量、1,2月最大冻土深度与湖泊面积呈负相关关系。尕海湖水面的扩张是同期气温升高、降水量增大、蒸发量减少和冻土退化等因素共同作用的结果。
摘要:A non‐characteristic Cauchy problem for the time fractional order diffusion equation in the 2‐D setting is a severely ill‐posed problem . In this paper , a regularization solution is constructed for the problem by using Tikhonov method , and then the error estimate between regularation approximation solution and exact solution is given .%二维时间分数阶的扩散方程非特征Cauchy问题是一个严重不适定的问题,本文通过Tikhonov正则化方法构造正则解,并获得了正则近似解与精确解之间的误差。
摘要:Based on miRNAs expression profiling data sets , new data mining algorithms— tSVM‐kNN (t statistic with support vector machine‐k nearest neighbor ) is proposed . Firstly , an original selection is made to this set by characteristics using t‐statistic method . After that , both ideas in support vector machine(SVM )and k nearest neighbor (kNN )algorithms are combined as a classifier , i.e. , SVM‐kNN algorithm .Finally ,the classification results as outputs can be obtained .Then ,simulation experiments show that SVM‐kNN algorithm as a classifier can display a stronger ability compared with running SVM and kNN , respectively . As to the aspects of quantity and recognition accuracy with a miRNAs label , tSVM‐kNN algorithm only need five miRNAs but can get a precision of 96.08% in classification . Obviously , compared with some existed methods , the proposed algorithm has more advantages .%基于 miRNA 表达谱数据集,提出了一种新的数据挖掘算法——— tSVM‐kNN (t statistic with support vector machine‐k nearest neighbor).该算法的思想为:首先,采用统计量法对该数据集进行特征初选;其次,将融合了支持向量机和K‐最近邻判别法思想的算法———SVM‐kNN算法作为分类器;最后,输出分类结果.仿真实验表明, SVM‐kNN算法分类器的分类能力比单独运行SVM和 kNN都好;在miRNA “标签”的数量和识别精度方面, tSVM‐kNN算法只需要取5个miRNAs即可获得96.08%的分类准确率.与同类的算法相比,其具有明显的优越性.
摘要:Root rot is one of an A stragalus membranaceus disease seriously affecting A stragalus membranaceus production . The main pathogen are Fusarium solani and Fusarium oxysporum . In this study ,the root of Astragalus membranaceus obtained from Gansu Longxi are isolated with pathogens , and then tested its pathogenicity through tissue isolation , root inoculation , pot experiment . Finally , obtained 5 strains of A stragalus membranaceus root rot pathogens , stain G2 , G3 and G4 are identified to Fusarium solani , strain G5 and G6 are identified to Fusarium ox ysporum by culture characteristics , microscopic morphology and rDNA ITS sequences analysis .%黄芪根腐病是严重影响黄芪产量的病害之一,为确定其致病的主要致病菌,本实验对采自甘肃陇西的黄芪根腐病病株以组织分离、离体根部接种、盆栽实验法进行病原菌的分离和致病性测定。结果获得了5株黄芪根腐病致病菌,并通过培养特征、显微形态及 rDNA ITS序列分析综合鉴定,确定菌株G2、G3、G4为茄腐镰刀菌(Fusarium solani),G5、G6为尖孢镰刀菌(Fusarium xoysporum)。
摘要:To explore the effects of Chinese medicine mixture on ephedrine‐induced liver damage in the pregnant mice , the 72 pregnant mice are randomly divided into control group , ephedrine group and Chinese medicine group . Ephedrine group and Chinese medicine group are injected with 0.043 g · kg -1 doses of ephedrine . Chinese medicine group is intragastric with 0.2 mL Chinese medicine mixture after injected ephedrine 1 h . T he changes of the behaviour of pregnant mice are recorded . T he changes of the activity of T‐AOC , GST are detected as well as the content of MDA by colorimetry , and the changes of liver tissue structure are observed by microscopy . Result show s that the eating and drinking reduce , jumping number increases , the activity of T‐AOC and GST decrease significantly , the content of MDA increases in the liver in ephedrine group , and the tissue structure has different degrees damaged , for example , hepatic sinusoid expansion , endotheliocyte off , hepatic lobules boundaries disorder and liver cell vacuoles . In Chinese medicine group , the eating and drinking increase , jumping number decreases , the activity of T‐AOC and GST are higher , and the content of MDA is lower . The damage of the tissue structure reduces significantly . Liver lobule boundary is clear . Endotheliocyte off is reduced significantly , and liver cell structure is normal . Ephedrine can inhibit the activity of antioxidant enzymes of the cell and has obvious damage in the liver tissue structure . The Chinese medicine mixture can significantly improve the antioxidant activity of the cell and helps to protect ephedrine‐induced liver damage of the pregnant mice .%为探讨中药混合液对麻黄素致损伤孕鼠肝组织的保护作用,将72例受孕小鼠随机分为对照组、麻黄素组和中药组,麻黄素组和中药组连续腹腔注射0.043 g·kg -1剂量的麻黄素溶液,中药组在注射麻黄素溶液1 h后灌胃0.2 mL中药混合液,记录孕鼠行为的变化,比色法测定肝组织 T‐AOC、GST 活性及MDA含量,生物显微技术观察孕鼠肝组织结构的变化.结果显示麻黄素组孕鼠饮食、饮水量减少,跳动次数增多,肝组织 T‐AOC、GST 活性显著降低, MDA含量明显升高,肝组织出现不同程度的损伤,肝血窦扩张,内皮细胞脱落,肝小叶界限紊乱,肝细胞空泡化;中药组孕鼠饮食、饮水量增多,跳动次数减少,肝组织T‐AOC、GST活性显著升高,MDA含量显著降低,肝组织结构损伤明显减轻,肝小叶界限清晰,内皮细胞脱落减少,肝细胞结构基本正常.表明麻黄素抑制细胞的抗氧化酶活性,对肝组织结构有明显的损伤作用,而中药混合液可显著提高组织细胞的抗氧化能力,改善细胞活力,对麻黄素致损伤孕鼠肝组织有一定的保护作用.
摘要:为了克服首位度分析的简单化,避免位序‐规模模式的不可比性,选取国家最大城市人口规模( P)、城市首位比(R)和城镇等级体系不平衡指数(S)3个指标来分析国家城市等级体系的世界格局。首先将156个国家的城市人口分为10~25万、25~50万、50~100万、100~500万以及500万以上5个等级,计算出城镇等级体系不平衡指数(S)和城市首位比(R),剔除 S=1的31个国家,然后对 P ,R和 S 采用系统聚类法(Hierarchical cluster )和自组织映射法(SOFM )来揭示国家城市等级体系的世界格局。结果表明,国家城市等级体系的空间格局可以分成6大类型:高级‐中级平衡型、中级平衡型、初级平衡型、初‐中级不平衡型、初级不平衡型和初级首位型。分类结果说明利用自组织特征映射法(SOFM )对国家城市等级体系进行分类,分类效果较好,可以反映城市等级体系国家间的异同。%In order to overcome the simplicity of the primacy index and the incommensurability of the rank‐size model , this paper selects unbalanced index of the urban hierarchy system (S) , the population of the largestcity(P)andurbanprimacyratio(R)tostudytheworldpatternofnationalurbanhierarchysystem . On this basis , firstly the 156 national city population is divided into 10~25 million , 25~50 million , 50~100 million ,100 ~ 500 million , more than 500 million of 5 grade , calculating unbalanced index of the urban hierarchy system (S) and city primacy ratio (R) , removing 31 countries of S= 1 , at last using hierarchical cluster and SOFM to reveal the world pattern of national urban hierarchy system . The result shos , that the world pattern of national urban hierarchy system can be divided into 6 types :the higher‐medium grade balance , the medium grade balance , the primary grade balance , the primary‐medium grade unbalance , the primary grade unbalance and the primary primacy . Classification results show that the classification effect is good , and it can reflect the similarities and differences between the nations using .
摘要:Let R be a commutative QF ring and A be an Artinian R‐module . If A has finite projective dimension , then A possesses a Gorenstein flat cover w hich is Artinian .%设 R是一个交换QF环, A是具有有限投射维数的Artin模,则 A的Gorenstein平坦覆盖是Artin的。
摘要:利用基于多组态Driac‐Fock(MCDF)理论方法发展的程序包GRASP及FAC程序包,详细计算了共振双激发态1s2l2 l′的共振能量、自电离速率、辐射速率及双电子复合截面。重点讨论了Breit相互作用对类氦钨离子双电子复合截面的影响。%By using the program package of GRASP and FAC w hich are based on the multiconfiguration Dirac‐Fack method , the resonant energy , radiative decay rates , autoionization rates of the doubly excited states 1s2ls l′and the corresponding dielectronic recombination (DR) cross sections have been calculated for He‐like tungsten ions . It focuses on the influence of the Breit interaction on the DR cross sections .
摘要:为了提高图像LSB隐写时的嵌入容量与视觉质量,结合图像的位面图内容特性,提出了一种基于图像 PCNN分割的LSB自适应隐写方案。该方案对图像的前4个位面图分别进行PCNN图像分割,并计算分割结果之和,以此作为各像素可以嵌入的秘密信息比特数,然后采用LSB方法进行隐写。实验结果表明,该算法具有较好的视觉隐蔽性和较高的数据嵌入量,而且不需要存储额外的嵌入深度信息。%In order to improve the embedding capacity and visual quality in image LSB steganographic , combining with the character of cover's biplanes , a novel LSB steganographic embedding based on PCNN image segmentation is presented . The method extracts the first 4 plane images and partitions by way of PCNN method , then adds the 4 segmentation as the number of embedded for every pixel and embed secret information with LSB . Experimental results show that the proposed method not only provides better visual quality and higher payload , but also does not save the embedding length data .
摘要:以花椒籽废渣为原料,在N2气氛下用ZnCl2活化制备了活性炭,采用FT‐IR ,BET ,XRD ,SEM和TG对制备的活性炭进行了表征.在碳化温度700℃、碳化时间60 min、ZnCl2浓度50%(质量比)、ZnCl2溶液与花椒籽废渣质量比为1.5的条件下,制备的活性炭具有高度破裂的多孔表面,比表面积为883.4 m2·g -1,总孔体积为0.55 cm3·g -1,平均孔径为2.47 nm .以制得的活性炭为吸附剂,研究了其对对硝基苯酚的吸附行为.结果表明,在吸附剂投加量为0.5 g·L -1、温度293 K、pH=8.0、吸附时间为6 h时,制备的活性炭对对硝基苯酚的吸附容量为334 mg·g -1,吸附可用Sips等温方程较好模拟,吸附为自发的吸热过程,吸附符合准二级动力学模型.%Activated carbons are prepared from waste residue of Chinese prickly ash seeds activated by ZnCl2 in N2 atmosphere.It is characterized by the methods of FT‐IR ,BET ,XRD ,SEM and TG .Under the conditions that ZnCl2 concentration is 50% (mass ratio ) , weight ratio of ZnCl2 to waste residue of Chinese prickly ash seeds is 1.5 , carbonization time is 60 min and carbonization temperature is at 700 ℃ , activated carbons prepared have highly cracked porous surfaces , grooves and macroporous . The BET surface area , total pore volume and pore volume are 883.4 m2 · g -1 , 0.55 cm3 · g -1 and 2.47 nm , respectively . It is used as adsorbent for the removal of p‐nitrophenol from aqueous solution . The adsorption capacity can be achieved to 334 mg·g -1 at adsorbent dose of 0.5 g·L -1 , adsorption temperature at 293 K ,solution pH of 8.0 and reaction time of 6 h . Thermodynamic study shows that the adsorption process can be favorably described by the Sips isotherm equation . Thermodynamic function calculated shows that the adsorption is a spontaneous and endothermic process . The adsorption kinetics can be satisfactory fitted by the pseudo‐second‐order model .
摘要:运用密度泛函理论(DFT )B3LYP方法研究了单重态和三重态势能面自旋禁阻反应Zr活化2‐丁炔分子的C—C和C— H键的反应机理.通过自旋‐轨道耦合的计算讨论了势能面交叉点和可能的自旋翻转过程.反应从基态三重态开始,在活化C—C键的反应过程中出现了自旋态的改变,使得过渡态3 T4g的活化能垒从-3.58降到-10.60 kJ· mol-1.在M ECP4处,单重态和三重态间的自旋‐轨道耦合常数为146.10 cm -1,反应发生有效的系间窜越,从三重态跃迁到单重态势能面,反应势垒有所下降.%The mechanism of the spin‐forbidden reaction Zr (3 F) and 2‐butyne on singlet and triplet potential energy surface(PESs) has been investigated by DFT of B3LYP .Crossing points between the different potential energy surfaces and the possible spin inversion process are discussed by spin‐orbit coupling (SOC) calculations . The reacting system starts in the triplet ground state , the changes of the spin state probably occur the activation of C—C , lead to a significant decrease in the barrier height of transition state 3 T4g from -3.58 to -10.60 kJ·mol-1 . The values of the SOC constants at minimum energy crossing point (MECP4) are 146.10 cm -1 between singlet and triplet PESs . The effective intersystem crossing (ISC) between different triplet and singlet PESs can occur and obviously reduce energy barriers .
摘要:为分离药用植物中内生真菌,从次级代谢产物中筛选对单胺氧化酶和乙酰胆碱酯酶有较高抑制率的提取物。用分块法分离5种植物,马铃薯葡萄糖琼脂(PDA )培养基纯化内生真菌,液体培养基发酵,用乙酸乙酯萃取菌液,甲醇提取菌丝体,用酶标法检测提取物对单胺氧化酶和乙酰胆碱酯酶的抑制率。共分离得到45株菌,制备了90种提取物,其中5株菌的菌液提取物对单胺氧化酶有不同程度的抑制率,露蕊乌头39(L RW T‐39)的菌液提取物对单胺氧化酶的抑制率最高,所有提取物对乙酰胆碱酯酶的抑制率不高。表明药用植物内生真菌中存在抗单胺氧化酶的活性成分,值得进一步研究。%Endophytic fungi is isolated from medicinal plants and higher inhibition rate of inhibition of monoamine oxidase(MAO) and acetylcholinesterase(AChE) are found from their secondary metabolites . Endophytic fungi is isolated by issue‐culture method and purified by potato dextrose agar medium . The fermentation of endophytic fungi are extracted by ethyl acetate , and the mycelium of endophytes are extracted by methanol to obtain methanol fractions . All fungi are tested for AChE and MAO inhibiting activity by colorimetric method in 96‐well microplates . Results show that 45 strains of endophytic fungi are isolated and extracted to obtain 90 extracts . Among them ,5 strains of Fungi exhibite significant anti‐monoamine oxidase activity . The ethyl acetate extract of LRWT‐39 are demonstrated to have most high activity against MAO . The active constituents in the endophytic Fungi of medicinal plants are worthy to be further studied .
摘要:Lycopene is one of the most abundant carotenoid w hich has multiple activities . In order to promote the application of lycopene in medicine , its antioxidant effect is discussed in this papper . The reducing activity , scavenging effects of both hydroxyl radical and superoxide anion , protections against the lipid peroxidation are measured by potassium ferricyanide method , deoxyribose degradation method , autoxidation of pyrogallol method and thiobarbituric acid colouration method , respectively . The detection of and oxidative damage of cells , protein , DNA are done by MTT method , SDS‐PAGE , capillary electrophoresis ,and all the test are compared with quercetin . The results indicate that lycopene shows some reducing activity and powerful ability of scavenging on free radicals . The EC50 for the elimination of hydroxyl radical and superoxide anion are 0.02 and 69.31 μmol · L -1 , respectively . Lycopene show s inhibiting effect of lipid peroxidation with IC 50 value of 20.8 μmol · L -1 and obviously protective effect on cells and DNA from H2 O2‐induced oxidative damage at the concentration of 5 μmol · L -1 . Also , lycopene is more active than quercetin in these systems .%番茄红素是最主要的类胡萝卜素,且具有多种生理活性.为了促进番茄红素在医药方面的应用,通过铁氰化钾法、脱氧核糖降解法、邻苯三酚自氧化法以及硫代巴比妥酸比色法检测番茄红素的还原力,以及对羟自由基、超氧阴离子的清除作用和对脂质过氧化的抑制作用;用M T T法、SDS‐PAGE法以及毛细管电泳检测番茄红素对细胞、蛋白质以及DNA氧化损伤的保护作用,用槲皮素为对照,研究番茄红素的抗氧化活性.结果表明,番茄红素具有一定的还原力和较强的自由基清除能力,对羟自由基和超氧阴离子的EC50分别为0.02和69.31μmol·L -1;抑制脂质过氧化的IC50为20.8μmol·L -1,在浓度为5μmol·L -1时对细胞、DNA的氧化损伤具有明显保护作用,且活性均比槲皮素强.表明番茄红素具有较强抗氧化活性.
摘要:T his paper mainly gives the sufficient and necessary conditions making the representation category of partial entwined modules be a braided monoidal category .%给出了使partial缠绕模范畴成为辫子monoidal范畴的充要条件。
摘要:The differentiability theorem of solutions with respect to initial conditions is established for Carathe′odory systems by using the differentiability of solutions with respect to initial conditions for generalized ordinary differential equations .%利用广义常微分方程的解相对于初值条件的可微性获得了Carathe′odory系统的解相对于初值条件的可微性。
摘要:This paper develops a dual‐sourcing supply chain for random newsvendor model composed of two unreliable suppliers and one retailer under random disruption environment . On unconstrained and budget cost constraints both cases , the optimal ordering strategy of the retailer is given , and the effect of disruption time to the optimal ordering quantity and the maximal expection of the retailer are analysed , and the existence of retailer’s optimal ordering quantity is proved . Finally , the specific effect of disruption time to ordering quantity and the maximal expection profit is explained through the numerical example .%在随机中断环境下建立了由两个不可靠供应商和一个零售商组成的双源供应链的随机报童模型。就无约束和预算费用约束两种情形,给出了零售商的最优订购策略,进而分析了随机中断时刻对最优订购数量和零售商最大期望利润的影响,证明了零售商最优订购量的存在性。最后通过数值实例分析了随机中断时刻对订购数量和最大期望利润的具体影响。
摘要:在基于FPGA的时频分析研究设计中,针对直接显示的时频谱图无法体现频谱细节变化的问题,提出了一种适合硬件实现的谱图增强算法。该算法以正弦信号的频谱结构为原型,选用反比例函数逼近正弦信号的频谱包络,并结合实际应用情况推导出具体的增强算法,利用该算法不仅对时频谱图的灰度级进行了压缩,而且进行了谱图增强处理。实验结果表明,此算法可有效显示出时频谱图的细节变化,与对数变换相比,具有运算量小,实时性好,适合硬件实现等特点。%During the research and design of time‐frequency analysis based on FPGA , the direct indication of the time‐frequency spectrogram is not able to reflect the variation of spectrum in detail . To solve this problem , an image enhancement algorithm of time‐frequency spectrogram based on FPGA is presented in this paper . The algorithm takes sinusoidal signal spectrum structure as design prototype , chooses the inverse proportion function to approximate the spectral envelope of sinusoidal signal , combines with the practical application to derive the specific enhancement algorithms . T he algorithm can not only compress the gray level of time‐frequency spectrogram , but also enhance the image . Experimental results show that more detail variation of time‐frequency spectrogram can be obtained by the algorithm effectively . Algorithm in this paper has the characteristics of much less computation , strong real‐time property and suitable for hardware implementation compared with logarithmic transform .
摘要:通过分析促食欲素A(Orexin A)在牦牛和黄牛消化道不同部位的分布特征及表达差异,探讨Orexin A对牦牛能量代谢的调节作用.运用免疫组织化学SP法检测Orexin A在牦牛和黄牛胃肠道的表达,利用Image‐ProPlus 6.0软件对其表达强度进行半定量分析.结果表明, Orexin A在牦牛和黄牛的皱胃、幽门、贲门和十二指肠均有表达,但表达特征不同;牦牛胃和十二指肠中Orexin A阳性反应产物极显著地低于黄牛(P<0.01);牦牛胃肠道中Orexin A阳性反应产物的吸光度分布为:皱胃区>幽门区>贲门区>十二指肠区(P<0.01).推测牦牛通过胃肠道Orexin A的低表达,调节中枢及外周组织的激素水平,从而维持机体能量代谢水平,适应青藏高原的特殊环境.%To explore the regulation effect of Orexin A on energy metabolism of yak by analyzing the difference of distribution and expression in gastrointestinal tract between yak and cattle . Immunohistochemistry is used to localize the expression of Orexin A in the gastrointestinal tract of the yak ,Image‐ProPlus 6.0 software is used to semi‐quantitative analyse the intensity of expression of Orexin A . Results show that Orexin A is widely expressed in the abomasum ,pylorus and duodenum cardia in yak and cattle ,which have different expressional characteristics ;The mean absorbance of Orexin A positive reaction product in stomach tissue and duodenum of yak is significantly lower than that of cattle ( P<0.01);By comparing the mean absorbance of Orexin A positive reaction product in the yak , it is found that its expression from strong to weak successively is abomasums area , pyloric region , cardiac region , and then duodenum area (P<0.01) .It indicats that the lower expression of Orexin A could regulate the hormone levels in the central and peripheral tissues to maintain its energy balance to adapt to the extreme environment of the Tibetan plateau .
摘要:定义了Cartan‐Eilenberg(CE) Gorenstein合冲复形,证明了对任意正整数 n ,复形 K是CE Gorenstein n‐合冲复形当且仅当它是CE n‐合冲复形;给出了复形的CE Gorenstein投射维数的等价刻画。作为应用,证明了具有有限CE Gorenstein投射维数的复形存在CE Gorenstein投射预覆盖。%After introducing the concept of Cartan‐Eilenberg (CE ) Gorenstein syzygy complexes , it is proved that a complex K is CE Gorenstein n‐syzygy complex if and only if it is a CE n‐syzygy complex for any positive integer n . Furthermore , an equivalent characterization of CE Gorenstein projective dimension of complexes is given .As applications ,it is proved that a complex existing finite CE Gorenstein projective dimension has a CE Gorenstein projective precover .
摘要:以支持向量机关键部分核数的有效选定作为探究目标,从核函数选取规则着手,将遥感数据领域知识嵌入到核函数构造问题中,结合遥感数据本身特征提出一种能同时兼顾到样本亮度差异性和角度差异性的混合核函数选取方法,通过支持向量机传统核函数分类效果进行对比分析,表明混合核方法的有效性。%The technology of remote sensing image classification , selection of classification rules and the selection of kernel function affect the classification accuracy among the samples . The key part of the support vector machine(SVM ) kernel function is effectively selection as exploration target rules from the selection of kernel function . The remote sensing data knowledge embedded in the kernel function structure problems ,combined with the feature of remote sensing data itself can put forward a kind of both samples to the brightness difference and angle difference of the mixed kernel function selection method . The kernel function of SVM and traditional SVM classification effect are analyzed to show the effectiveness of mixed kernel methods .
摘要:T he copolymerization of itaconic anhydride and propylene oxide to yield aliphatic polyester has been achieved through the use of zinc glutarate . The structure of copolymers is characterized by FT‐IR and 1 HNMR . The copolymerization conditions including reaction temperature , reaction time , monomer molar ratio and catalyst concentration are investigated in detail . It has found that the obvious cross‐linking in the copolymerization of itaconic anhydride and propylene is oxided owing to the high activity of exo‐type double bond of itaconic anhydride . The results showed that the optimum reaction conditions are as follows :temperature 100 ℃ ,time 96 h ,monomer molar ratio 1∶1 ,catalyst concentration 0.01 g・mL -1 .%利用戊二酸锌(ZnGA)催化衣康酸酐(IAn)和环氧丙烷(PO)共聚合制备聚酯,采用FT‐IR和1 HNMR对聚合物结构进行了表征.考察了聚合反应温度、反应时间、单体摩尔比和催化剂浓度对共聚合反应的影响.结果表明, ZnGA能够有效催化IAn与PO共聚,共聚合反应中交联现象明显.优化聚合反应条件,确定最佳条件为:反应温度为100℃,时间为96 h ,单体摩尔比为1∶1,催化剂浓度为0.01 g・m L -1.
摘要:以盐生植物黄花补血草幼苗为供试材料,研究了不同浓度NaCl(0,25,50,100,150 mmol・L -1)胁迫下叶片抗坏血酸‐谷胱甘肽(AsA‐GSH)循环中抗氧化物质含量和抗氧化酶活性的变化。结果显示:150 mmol・L -1 NaCl处理诱导幼苗叶片AsA和总抗坏血酸含量增加;所有盐浓度诱导脱氢抗坏血酸(DHA)含量、GSH/氧化型谷胱甘肽(GSSG)比值升高,谷胱甘肽还原酶(GR)、抗坏血酸酶(AAO)和脱氢抗坏血酸还原酶(DHAR)活性增强,而AsA/DHA比值、GSSG含量和单脱氢抗坏血酸还原酶(MDHAR)活性降低。此外,低浓度盐胁迫下幼苗叶片GSH含量升高,而高浓度盐处理诱导叶片GS H含量降低。表明盐胁迫下黄花补血草幼苗叶片提高了非酶抗氧化物质含量和抗氧化酶活性,增强了幼苗清除活性氧的能力,增强了对盐胁迫的耐受能力。%Halophyte Limonium aureum (L ) Hill seedlings are used to investigate the changes of antioxidant substance contents and antioxidant enzyme activities associated with ascorbate‐glutathione (AsA‐GSH) cycle in respones to different NaCl concentrations (0 ,25 ,50 ,100 ,150 mmol・L -1 ) . The amount of ascorbic acid (AsA ) and total ascorbic acid contents rise due to only 150 mmol・L -1 NaCl . Differently ,all salinity concentrations lead to the increases of dehydroascorbate(DHA) content ,GSH/oxidized glutathione(GSSG) and glutathione reductase(GR) , ascorhic oxidas(AAO) and dehydroascorbate reductase(DHAR) activities ,but the decreases of AsA/DHA , GSSG level and monodehydroascorbate reductase ( MDHAR ) activities . In addition , GSH content increases in response to low NaCl concentrations but decreases to high salinity in the leaves of Limonium aureum(L) Hill seedlings . Taken together , salinity stress results in the increases of non‐enzymatic antioxidant levels and antioxidant enzyme activities in the leaves of Limonium aureum(L) Hill seedlings ,which might enhance the ability of reactive oxygen species scavenging and strengthen seedling resistance to salt stress .
摘要:针对人脸图像数据量大和DBNs初始化权值具有指向性以及非凸目标函数易陷入局部最优的问题,提出将主分量分析(PCA)、遗传算法(GA)、深度信念网络(DBNs)相结合的新算法,并将其应用在人脸识别中。首先通过 PCA对人脸图像进行处理,以减小人脸图像的数据量,然后利用GA算法对DBNs进行逐层预训练以优化其网络权值,再利用BP算法对DBNs进行微调并构造分类器。以ORL数据库为实验数据通过与其他经典人脸识别算法的比较得出,该算法不仅可以减少人脸图像数据量,而且可以克服初始权值的指向性和局部最优问题,更重要的是可以提高识别精度和识别速度。%Aiming at the problem that the data volume of face image and DBNs initialization weight are pointed and the non convex objective function is easy to fall into local optimum , a new algorithm combining principal component analysis(PCA) ,genetic algorithm(GA) and deep belief network(DBNs) is proposed , w hich is applied to face recognition . Firstly , the face image is processed by PCA to reduce the amount of data . Then the GA is trained by DBNs algorithm to achieve the purpose of optimizing the weights . Then the BP algorithm is used to fine tune the DBNs and construct the classifier . According to the experimental results of ORL database , the proposed algorithm can not only reduce the amount of human face image data , but also overcome the initial weight of the directional and local optimization problems .More important ,it is to improve the recognition accuracy and convergence speed .
摘要:合成了两种含 POSS 的金属铱(Ir)配合物磷光材料 POSS‐7Cz‐Ir(L)2(q)(POSS‐1)和 POSS‐6Cz‐2Ir(L)2(q)(POSS‐2)。用1 HNMR、FT‐IR和MS对配体和磷光材料的结构进行了表征,并分别测定了两种磷光材料的紫外‐可见吸收光谱及光致发射光谱,通过热重和X RD分析了其稳定性。%Two new phosphorescent iridium(Ir) complexes containing polyhedral oligomeric silsesquioxane (POSS) core , such as POSS‐7Cz‐Ir (L )2 (q ) (POSS‐1 ) and POSS‐6Cz‐2Ir (L )2 (q ) (POSS‐2 ) , are synthesized and characterized by 1 HNMR , FT‐IR and MS . Their UV‐vis absorption and photoluminescence spectra are investigated . The thermal stability and morphology of POSS‐1 and POSS‐2 are also investigated by TG and XRD analysis .