Research on multiple elimination methods in inverse data space based on randomized singular value decomposition

Based on surfaced-related multiple elimination (SRME),this research has derived the methods on multiples elimination in the inverse data space.Inverse data processing means moving seismic data from forward data space (FDS) to inverse data space (IDS).The surface-related multiples and primaries can then be separated in the IDS,since surface-related multiples will form a focus region in the IDS.Muting the multiples energy can achieve the purpose of multiples elimination and avoid the damage to primaries energy during the process of adaptive subtraction.Randomized singular value decomposition (RSVD) is used to enhance calculation speed and improve the accuracy in the conversion of FDS to IDS.The synthetic shot record of the salt dome model shows that the relationship between primaries and multiples is simple and clear,and RSVD can easily eliminate multiples and save primaries energy.Compared with conventional multiples elimination methods and ordinary methods of multiples elimination in the inverse data space,this technique has an advantage of high calculation speed and reliable outcomes.     

麦地复播玉米及其青贮研究

麦地复播玉米 ,以新玉— 7号较好 ,施尿素 30 0kg/hm2 时其产量最高 ,在秋季重霜来临之前收割玉米茎杆进行青贮 ,40天后可饲用     

On multiple solutions to a low-spectrum model of oceanic current driven by the boundary force—The bimodality of the Kuroshio south of Japan

This low-spectrum model study on the multiple solutions to a nonlinear quasi-geostrophic oceanic current equation shows that they depend on the combination ofRo, Re, λ and ε, that the bimodality of the Kuroshio depends strongly on the nonlinear effect represented byRo and λ, and that its occurrence probability is reduced by the dissipation represented byRe and ε. The stability of solutions is discussed in detail with Hurwitz's theory. This work was supported by NSFC (No. 49070252)     

西太平洋西北海域海温与西副高和极涡的联系

本文通过西太平洋西北部海表温度与北半球500hpa西副高和极涡环流指数的典型相关分析,得到了一些有意义的环流超前与滞后的相关事实,证实了环流有3—6个月的滞后相关的存在。     

三步组合法衰减深水多次波

深水地震资料多次波具有能量强、周期长的特点,降低了资料的信噪比,是处理人员面临的首要问题。多次波衰减效果的好坏,直接影响着最终成像效果及后期储层反演结果的真实性。分析深水多次波的类型、成因和特征,并研究各种多次波衰减技术的优缺点和适用性,最终合理组合多方法、分步衰减多次波是关键。以南海A区深水地震资料为例,通过组合优选基于模型的SRME技术和高分辨率Radon技术进行了实际应用,并就出现的剩余多次波给予分析和改进,提出了“三步法”衰减深水多次波,应用后取得了显著的多次波衰减效果。     

斑节对虾形态性状对体质量影响的分析

经济性状是对虾遗传育种的重要指标, 形态参数对于经济性状的贡献率是选育参数的重要依据。为了研究斑节对虾(Penaeus monodon)表型性状间的相关性及影响体质量的因素组成, 随机选取1 339 尾6 月龄对虾, 对其形态性状(体长、头胸甲长、头胸甲高、头胸甲宽)和体质量性状5 个数量性状进行测量, 并应用相关分析、多元回归、通径分析、决定系数等方法讨论了形态性状对体质量性状的影响。结果表明, 所测各形态性状间的相关性均达到极显著水平(P<0.01); 其中体长(P=0.563)对体质量的直接影响较大, 是影响体质量的主要因素。决定系数分析结果与通径分析结果一致, 各表型性状对体质量的总决定系数Σd=0.925, 表明所选性状是影响体质量的主要性状。通过逐步回归分析方法,经偏回归系数显著性检验, 建立了体质量为因变量, 体长、头胸甲长、头胸甲高和头胸甲宽为自变量的多元回归回归方程:Y= –22.489 + 0.22X₁+ 0.191X₂+ 0.339X₃+ 0.296X₄, 为斑节对虾选育提供了理论依据。     

逐步线性回归法实现天津厚蟹(Helice tientsinensis)表型性状与体重的通径分析

选择莱州湾的天津厚蟹(Helice tientsinensis)140只, 测量甲长(X1)、大螯动指长(X2)、甲宽(X3)、眼间距(X4)、第Ⅰ侧齿间距(X5)、第Ⅱ侧齿间距(X6)、大螯不动指长(X7)、大螯不动指宽(X8)、大螯长节长(X9)、第Ⅰ步足长节长(X10)、体高(X11)、体重(Y)共12个指标, 采用相关分析和通径分析方法, 计算了以形态性状为自变量, 体重作依变量的通径系数、相关系数和决定系数。结果表明, 所测形态性状与体重的相关系数均达到极显著水平(P<0.01); 采用逐步线性回归的方法建立了多元回归方程Y =－16.448 + 1.063X1 + 0.466X2, 其中Y为体重(g), X1为甲长(mm), X2为大螯动指长(mm)。选取的形态性状与体重的复相关指数R2=0.856, 定量分析了形态性状对体重的影响效果。     

Oceanic upwelling produced by northerly winds on the north Canterbury coast,New Zealand

The rates of upwelling calculated from the change in temperature distribution derived from two sets of hydrological stations (0.0107 cm.r^‐1) and the rate of upwelling calculated from the wind derived transport offshore for the period between the collection of the hydrological data (0.0086 cm.s^‐1) are found to be consistent.     

The other 93%: trophic cascades,stressors and managing coastlines in non-marine protected areas

Abstract

This paper reviews interactions involving stands of macroalgae on rocky reefs, and presents new data on changing sea surface temperatures (SSTs), as a contribution to the celebration of the fiftieth anniversary of the Leigh Marine Laboratory (LML) of the University of Auckland. The focus is on trophic interactions involving predators, sea urchins and large brown algae, particularly trophic cascades. Of the 369 publications arising from work at LML, 40 have been on key aspects of these trophic interactions. Quantitative investigations of the structure of kelp bed communities and mechanistic studies involving manipulative field-based experiments, essentially a bottom-up perspective based on habitats and key species, dominated the research through the 1980s. From the mid-1990s onwards, the focus was more on marine reserves and a hierarchical, top-down perspective of community structure, with a particular focus on the role of predatory fish, and marine reserves as a tool of management. I discuss these models of community structure of kelp beds within the wider context of the New Zealand nearshore zone, the varying biogeographic regimes around the coastline, diffuse stressors and the changing nearshore climate. I show there appears to have been a significant warming trend in SST in northeast and northwest New Zealand over the past 30 years. I conclude that a trophic effects model is unlikely to apply to much of the coastline of New Zealand, and that a model involving multiple effects, including bottom-up forces, environmental and climatic influences, species' demographics, and catchment-derived sedimentation is more appropriate for kelp communities over most of the country. New management models are needed to safeguard marine resources and the services they provide.     

多孔介质中水气交替注入微观渗流模拟

针对水气交替注入(water-alternating-gas,WAG)过程中,油气水三相渗流的微观机理认识不足和油气水三相流体在多孔介质中分布规律认识不准确等问题,基于三维孔隙网络模型,应用孔隙级模拟方法,从微观角度模拟了不同润湿性多孔介质中的WAG驱替过程.结果表明:连通性较好的多孔介质中,原油主要在前两轮的WAG循环中被驱替出来;在前两轮WAG驱替之后,流体饱和度和分布规律达到比较稳定的状态,但在完全水湿模型中油相仍然在多孔介质中流动.得出的WAG驱替过程中各相流体饱和度的变化规律、各相流体分布规律和驱替类型,较好地阐述和解释了多孔介质中的微观驱替机理.