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1.
本文给出诱导映射的定义.讨论其重要性质,提出其中每一条都可以作为诱导映射的另一定义,这有益于对诱导映射的不同刻画,扩大了诱导映射的范围。作者给出了诱导映射在格拓扑和格的代数同态方面的应用;同时作者力图把高层次的或不分明集上的“具有某种性质”的映射分解成低层次的或分明集上的同样“具有某种性质”的映射,这对不同特色的映射的构造是有意义的  相似文献   

2.
本文在不分明的意义下,对闭包、内部、半闭包及半内部进行研究,得到一些反映它们之间关系的性质定理,此外,当我们将闭包、内部、半闭包及半内部看作四种不同的运算作用到一个不分明集上,可以构造多少种不同的不分明集.对此,本文用若干定理给出了详细的回答.  相似文献   

3.
本文在文献[1]的基础上,另外给出不分明集是可数紧的充要条件,若不分明拓补空间满足C_1或Q—C_1公理,我们还得到可数不分明紧空间的几个等价条件:  相似文献   

4.
作者引入 I(L)值完全下半连续映射 ,研究其性质。利用 I(L)值完全下半连续映射定义I(L)值完全诱导空间 ,给出 I(L)值完全诱导空间的拓扑基的表达形式 ,证得两个 I(L)值完全诱导空间的映射是连续映射的充分必要条件 ,并建立了乘积空间的 I(L)值完全诱导空间与 I(L)值完全诱导空间的乘积空间的联系  相似文献   

5.
用函数对的概念将点到点,点到集及点到模糊集的映射的扩张原理推广,得到相应地广义扩张原理,并用集合套的观点给出等价条件。而广义扩张原理以查德扩张原理及刘文斌(1991)提出的新扩张原理为特殊情形。  相似文献   

6.
新定义的Fuzzifying半邻域系及其应用   总被引:1,自引:0,他引:1  
本文用新的方法引入fuzzifying半开集的概念;利用此半开集概念确定fuzzifying半邻域系。最后作为应用定义了映射的fuzzifying半连续性并给出若干刻画条件。  相似文献   

7.
几种海产双壳贝类血淋巴中抗菌物质的诱导及其活性测定   总被引:4,自引:1,他引:4  
以贻贝(Mytilus edulis),毛蚶(Scapharca subcrenata),海湾扇贝(Argopecten irdians)和菲律宾蛤仔(Ruditapes philippinesis)为试验材料,分别用活的和灭活的大肠杆菌为诱导物进行诱导,采用3种革兰氏阳性细菌和3种革兰氏阴性细菌作为指示菌,对4种供试双壳贝类血淋巴进行抗菌活性测定,结果表明:(1)贻贝在诱导前其血淋巴对金黄色葡萄球菌和四联微球菌有抑菌活性,免疫诱导可使血淋巴对鳗弧菌出现抑菌作用;(2)毛蚶在诱导前其血淋巴中含有对金黄色葡萄球菌和鳗弧菌有抑菌活性的物质,诱导对这两种菌的抑菌活性有明显的提高,但未诱导出对另外4种供试细菌有活性的物质;(3)海湾扇贝在诱导前其血淋巴对所有供试细胞均无抑菌活性,但经诱导后产生对金黄色葡萄球菌,副溶血弧菌和鳗弧菌有抑菌活性的物质,且活菌诱导比灭活诱导效果好;(4)菲律宾蛤仔在诱导前其血淋巴仅对金黄色葡萄球菌和鳗弧菌表现出抑菌活性,经诱导后其血淋巴不仅对这两种菌的抑菌活性增强,而且还诱导出对副溶血弧菌有抑菌活性的物质。  相似文献   

8.
应用DFD(Diverse Firewall Design)方法进行防火墙规则集设计时,需使用规则集语义比较算法,判断多个规则集是否语义一致。规则冲突是导致规则集语义不一致的主要原因。因此,需要研究针对规则冲突的规则集语义比较算法。而现有算法时空复杂度较高,性能低下。文中提出了1种基于关键数据包选取映射的规则集语义比较算法(KPCM)。KPCM算法针对规则冲突选取关键数据包,并通过比较这些数据包在不同规则集中的处理动作,判断这些规则集是否语义一致。理论分析和测试表明,KPCM算法时空性能均优于现有算法。  相似文献   

9.
最早由查德给出的扩张原理是F集理论的最基本的理论之一,它是普通概念F化的重要手段。因此,关于它的推广和各种等价形式的研究是非常有意义的工作。本文把基于普通的点到点的映射的扩张原理推广到点集映射,进而又推广到F映射。得到新的扩张原理是以查德的扩张原理为特殊情形的一种统一形式。  相似文献   

10.
对于广义Brouwer不动点问题的无界情形,研究者们主要针对凸集进行了一些研究,非凸集合还很少涉及。本文针对一类非凸集合,利用不动点问题的自映射以及新引入的二次连续可微映射构造了一组无界性条件,使得连续化方法能够求解无界非凸集合上的广义Brouwer不动点问题,并取得了该方法的全局收敛性结果,从而导致了可数值实现的全局收敛性算法。本文的研究结果在较大程度上推广了已有的研究结果,使得连续化方法能够处理更大一类不动点问题。  相似文献   

11.
In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance.  相似文献   

12.
海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明:土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。  相似文献   

13.
An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm.  相似文献   

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16.
A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria ( 〉 99% ), but also between polar marine bacteria and bacteria from other aquatic environments ( ≥ 98.8% ), including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.  相似文献   

17.
Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations.  相似文献   

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19.
《海洋学报(英文版)》2014,(8):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,  相似文献   

20.
Sediment properties, such as water content and density, have been used to estimate the dry and wet weights, as well as the volume of sediment recovered and discharged, during benthic impact experiments conducted in the Pacific and Indian Oceans. The estimates show that the weights of dry (355-1332 t) and wet sediment (1651-4888 t) recovered during the experiments, are not only a function of the total duration and distance covered during the experiment, but also depend on water content and density of the sediment. Estimation of dry sediment and its volumetric ratio in the discharge, are key parameters for calculating the discharged volume. The estimated volume of wet sediment recovered (1427-4049 m 3 ) as well as discharged (2693-6951 m 3 ) during the experiments, provide important inputs to evaluate the sediment resettlement and migration. Using these estimates, the average depth of excavation on the seafloor, can also been calculated. However, the stages of sediment recovery and discharge are expressed differently in some of the experiments. In order to standardize these, different stages have been identified, and definitions of certain terms have been suggested, for use in the future. The methods of calculating different properties, as well as weight and volume of discharged sediment are described in the paper for use in other applications concerning deep-sea discharges.  相似文献   

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