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881.
基于交互多模型的水下目标跟踪方法 总被引:2,自引:0,他引:2
根据水下目标机动的特点,给出了基于模糊逻辑推理的交互多模型方法。在仿真试验中,利用常速度模型、Singer模型和常速度转弯模型集合来覆盖水下目标的机动模式。仿真处理的结果表明,基于模糊逻辑的交互多模型算法能够提高水下机动目标跟踪的可靠性和实时性。 相似文献
882.
云的模拟是户外场景仿真的重要内容,由于受速度的限制,多采用BOX或DOME等建模方法,但效果不够逼真,且不能穿行.体云的模拟效果逼真,但交互速度慢.文中讨论了体云模拟的基本原理及如何利用云的多向前方散射的特性来建立体云的光照模型,该模型效果逼真,与真云一样具有银色的边缘.给出了一个预处理与实时计算相结合的算法,该算法可以利用硬件图形卡的特性,因而模拟速度较快,可以满足交互式实时模拟的需要. 相似文献
883.
Multiple equilibria and their stability in tropical atmosphere are investigated through β-plane
barotropic models with consideration of heating and dissipation. We have derived the solutions of the model
equations corresponding to the multiple equilibria or the steady flows first, and then establish the criteria for the stability of steady flow by use of the Liapunov direct Method. When these criteria are applied to the solutions of equilibria obtained, stable flows, which are closely related to the different patterns of quasi-stationary circulation in the tropical region, are found. The configurations of these stable flows and the shift between two of them as season changes provide quite reasonable explanations to many fundamental problems of tropical circulation features such as the catastrophe mechanism of the onset and the break-active cycle of the Asian summer
monsoon. It follows that the onset or the abrupt transition of the Asian summer monsoon could be attributed to
the multiple equilibrium property of the tropical circulation resulted from the advective nonlinearity, which
provide another explanation among others. 相似文献
884.
Multiple scattering of surface waves from discrete obstacles 总被引:1,自引:0,他引:1
885.
Elissa Sutherland 《The Australian geographer》2004,35(2):161-168
In this paper I reflect on some key methodological tensions that emerged during my PhD research. The research critically analyses the political struggles of outworking1 women from Chinese, Vietnamese and Cambodian backgrounds in Sydney, Australia, for minimum wages and a monitoring of ethical networks in the clothing industry from 1997 to 2002. Rather than present 'key findings' in this paper I instead reveal how I began to think more critically and in less absolute ways about reading the multiple voices of outworkers, NGO workers and my own voice as researcher, activist and English teacher. I drew insights from Bakhtin's dialogism for thinking about research as shaped by sets of conversations. In this paper I reflect on several 'in-the-field' interactions: organising interviews, interviewing outworkers through an interpreter, storytelling in a rights-based English class setting, and how I and other participants represented outworking women in different forums. Dialogism required I take seriously the concept that knowledges are socially constructed in very particular contexts and this led to a rejection of my earlier notion of a singular authentic voice for outworking women or for me as researcher. 相似文献
886.
以南江县红山铁矿1242m中段CM82中样品分析成果的统计分析为例,介绍运用多元统计方法确定矿产勘查中的基本分析项目的方法。 相似文献
887.
888.
两类多河道河流的形式模式及河道稳定性比较 总被引:8,自引:0,他引:8
在多河道河流中,网状河流作为有别于分汊河流和辫状河流的河型而提出已经引起人们的注意,但它与分汊河流的区别常常被忽略。为了阐明二者的根本差别,力求从多河道形成模式上对二者进行比较研究。通过对长江下游分汊河流及荆江风状河流特定河段形成历史及方式的探索,提出河道内的江心洲化模式和河漫滩上的河道化模式分别是分汊河流和网状河流形成的基本途径。由此而决定了网状河道具有分汊河流更高的稳定性。 相似文献
889.
A rule-based model for managing uncertainty in spatial databases is presented. The overall goal of the model is to allow
a user to assign to a single map class each polygon whose class is not entirely certain using more information than only the
map class attributes of such polygons (that are herein termed abjects). This situation might arise when multiple map realizations of an area are available and interpreters/cartographers are not
in agreement as to what class is present at a given location or when a digital image is classified by algorithmic/probabilistic
means. The scale-based model developed relies on attribute, geometric, and neighborhood measures of abjects arranged in a hierarchical rule-based structure. Structural knowledge of these measures leads to the procedural knowledge
that determines what action – e.g., merge, reclassify, retain – is to be taken for a given abject. The wider applicability of the model and associated methodology is also discussed.
Received: 5 July 2001 / Accepted: 11 April 2002 相似文献
890.