基于相似度模型的可融合兴趣点分类研究

研究了如何进一步提高兴趣点(POI)信息融合结果的准确性问题。定义了POI各个特征字段的相似度,并根据这些相似度构造出了POI相似模型,结合机器学习中的分类方法对网上抽取的POI进行分类,有效地区分出可融合、不可融合的POI。最后利用美团团购网上的信息仿真,仿真结果说明了本方法的有效性。     

基于数据相似度的多维海洋数据交互式集成可视化

为充分挖掘多维海洋数据中的隐藏信息,提出一种基于数据相似度的多维数据交互式集成可视化方法。引入平行坐 标作为交互工具,以颜色条带表示用户感兴趣数据集;设计一种迭代式 al pha颜色混合方法,对条带重叠区域的颜色进行处 理以实现相关信息的有效表征;引入数据相似度概念并给出形式化定义,通过颜色空间 RGB 与 HSL 之间的相互转换,改变 混合色亮度实现其区别表征。实验结果表明,基于数据相似度的多维数据集成可视化方法不仅能够将多个相关数据集以集成 的方式同时展现,并且还对各组交互数据集的相似度进行了区分表征,细化了信息展现层次,有效提高了可视化结果的信息 承载量。     

基于近海雷达与AIS探测目标融合算法研究

利用岸基雷达站的雷达传感器以及船舶自动识别系统(Automatic Identification System,AIS)所获取的目标信息,针对近岸海域目标密集的特点,提出了一种提高雷达与AIS信息融合精度的算法。该算法在将雷达基于站心球坐标系的位置信息转换成AIS基于WGS 84坐标系的位置信息实现空间配准、以及将AIS航迹的时间通过外推法与雷达航迹时间统一起来的基础上,首先采用目标位置及航速的欧氏距离判别法,剔除一部分不符合条件的目标数据,减少参与融合的数据量,然后进一步采用模糊数学中的柯西型隶属度函数及统计加权法对航迹相似度判断。研究结果表明,本文所提出的融合算法适用于目标较密集的近海海域。     

面状矢量空间数据匹配技术研究

数据匹配技术是空间数据集成与融合中的关键技术。对面积相似度进行了描述,对面积相似度进行了几何度量上的定义,提出了基于面积相似度的数据匹配思路。最后,以面状目标为研究对象,以城市居民地的大比例尺数据为例,对基于面积相似度的面状要素数据匹配算法进行了试验与分析。     

一种基于粗糙集和欧式距离的手机故障案例匹配算法

本文研究在云环境中手机故障案例检索时的案例匹配问题,提出了一种基于粗糙集和欧式距离的案例相似度匹配算法CMARE(Case Matching Algorithm based on Rough sets and Euclidean distance)。首先云计算平台收集手机故障参数,根据参数构建粗糙集信息表,利用粗糙集求出信息表里各案例特征参数的属性客观权重值并结合专家经验给出综合的属性权重值,最后利用此权重值和欧式距离计算案例间的相似度,找出案例库中与新案例最相似的案例。该算法的创新之处在于确定案例属性权重值时基于数据本身和人工经验,避免了过分依靠人工经验知识设定属性权重的不足;与规则推理方式不同,本文使用案例推理的方式。仿真实例说明了算法的有效性。     

“梅花”台风路径与强度的集合预报

以新一代全球/区域多尺度通用同化与数值预报系统-热带气旋路径数值预报系统(global/regional assimilation and prediction system-tropical cyclone model,GRAPES-TCM)为试验模式,采用组合不同的物理参数化方案(MP)方法和随机全倾向扰动(STTP)方法,生成反映模式不确定性的集合成员,在此基础上设计包含6个成员的3种集合方案,方案1和方案3的成员分别用MP方法和STTP方法生成,方案2的成员同时采用MP和STTP方法生成,用3种集合方案对1109台风"梅花"进行了36次72h的集合预报试验。结果显示:对于路径预报,3种集合方案中预报效果最好的是方案3,其次为方案2,最差的是方案1;对于强度预报,方案1和方案2的预报效果差异不大,都远好于方案3。方案2和方案3的路径预报与强度预报都好于控制试验的预报,方案1的路径预报好于大部分成员的预报,强度预报好于所有成员的预报。3种方案的路径离散度都偏小,方案3偏小最多,其次为方案2;方案3的强度离散度也过于偏小,是3种方案中最小的,方案1和方案2的强度离散度在积分前期明显偏小,积分后期则有偏大的趋势,其中方案2的强度离散度大于方案1。与国内外8个业务数值模式的预报结果比较,对于路径预报,方案1优于5个业务模式的预报,方案2和方案3则优于除欧洲数值以外的7个业务模式的预报;对于强度预报,方案1和方案2优于所有8个业务模式的预报,方案3优于6个业务模式的预报。总体而言,3种集合方案的路径和强度预报都表现出优于确定性预报的预报能力,相对于各业务数值模式都表现出一定的预报优势,具有业务应用的价值,其中同时应用STTP和MP方法的方案2对台风的综合预报效果是最优的。     

利用MAPX实现空间数据库与属性数据库的挂接

数据库是 GIS的基础 ,而空间数据库与属性数据库的挂接则是 GIS的要点。本文以渤海区域地质信息管理系统数据为例 ,阐述了基于 GIS的海洋地学管理信息系统中数据库的组织方法 ,包括空间数据库与属性数据库数据分类、分层方案 ,命名及编码规则。在此基础上 ,重点讨论了在 VisualBasic环境下运用 MAPX实现空间数据库与属性数据库的挂接方法。     

共转换点道集的抽取与转换波时变静校正

纵横波速度比固定时,同一地震道中各时间采样点对应不同的转换点位置,因此,常规的整体抽道方法只能抽取特定深度或特定层位条件下的共转换点道集,它不能保证所有P-SV转换波的反射点位置都在同一水平位置处。提出了一种精确抽取共转换点道集的新方法,运用这种方法抽取的共转换点道集中所有数据对应的转换点在地面的投影都对应于同一位置,因此,该道集是一种真正意义上的共转换点道集,在此基础上提出了一种解决短波长问题的转换波时变静校正方法,实际资料处理取得了好的效果。     

开关非局部中值滤波在海洋浅地层剖面随机噪音处理中的应用

本文结合理论模型与实际资料,论证了开关非局部中值滤波方法对浅地层剖面数据随机噪音的处理效果,着重讨论了该方法中的目标数据块宽度、搜索数据块宽度、相似度最优的数据点数以及噪音检测的阈值等相关参数对压制随机噪声效果的影响。目标数据块的宽度与相似度最优的数据点数均需要参照搜索数据块宽度,因此该参数的选取最为重要。结果表明优选滤波参数能够有效压制随机噪声,增强同相轴连续性,提高剖面信噪比。     

一种改进的Curvelet变换遥感影像融合方法

提出了一种改进的Curvelet变换的融合算法,以IKONOS影像为样本数据,融合过程中将原全色波段与多光谱影像中未参与HIS分解的波段进行加权组合,形成新全色分量,再将此分量与明度分量分别进行第二代Curvelet变换,以形成新明度分量,HIS逆变换后形成融合影像。并与改进的HIS变换融合、传统的HIS变换与Curvelet变换结合的融合算法相比较,结果表明,改进的方法能增加融合影像的信息量,降低光谱扭曲度,提高融合影像与原多光谱影像的相似度。     

Microbial Biomass and Organic Nutrients in the Deep-Sea Sediments of the Central Indian Ocean Basin

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.     

海上大直径钢管桩打桩过程中桩周土强度弱化研究

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。     

Geoacoustic Inversion via Genetic Algorithm and Its Application to Manganese Sediment Identification

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.     

Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans

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.     

Deep-Sea Sediment Compression Curves: Some Controlling Factors, Spurious Overconsolidation, Predictions, and Geophysical Reproduction

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.     

INFORMATION FOR AUTHORS

<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,     

Evaluation of the Risk of Marine Slope Instability: A Pseudo-3D Approach for Application to Large Areas

This article presents a methodology developed to evaluate the instability of submarine slopes that extend over a large area. Special attention was paid to (1) the complex geometry (bathymetry) and the expanse of the slope, (2) the heterogeneity of the sediment, and (3) the distribution of the pore pressure. The safety factor was considered as a spatially varying quantity. The General Formulation (GLE, Fredlund and Krahn 1977), which fully satisfies equilibrium conditions, was used for evaluating the stability of the marine slope. The submarine slope failure, which occurred on 16 October 1979 during the construction of the new Nice airport, was studied in order to test the developed model. Geotechnical parameters were taken from experimental tests carried out by IFREMER on 19 cores extracted at different depths (from 27 m to 1300 m) (Cochonat, Bourillet, and Savoye, 1993; Mulder et al., 1994). Many scenarios were proposed in order to explain the cause of the Nice slope failure (Habib, 1994). In this article, two of those scenarios were tested. Simulation results are presented and discussed.