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排序方式: 共有200条查询结果,搜索用时 15 毫秒
1.
多媒体数据库管理的数据表示模型与融合 总被引:1,自引:0,他引:1
通过定义角色、虚拟角色、观点和虚拟观点,解决了多媒体信息的格式不同给用户造成的使用不便,同时也较好地解决了多媒体数据融合的技术关键。角色和观点掩饰了所有由信息和日常所需的格式的复杂性,利用角色和观点来支撑多媒体对象的动态扩展,致使多媒体制造者能够很容易地在运行时延伸对象的使用。 相似文献
2.
井下抽油泵柱塞与泵筒运动规律的研究 总被引:1,自引:0,他引:1
用三元振动模型,综合考虑油柱、抽油杆柱和油管柱的振动.建立起数学模型并离散化,然后用微机编程求解微分方程组.对不同工况下的抽油泵运动规律和抽油机示功图进行分析研究,得出了油管应予锚定的结论,并给出了不同抽油机的适用范围.为进一步研究抽油泵的井下工作机理和故障原因打下了基础. 相似文献
3.
张庆文 《系统工程与电子技术》1994,(9)
本文利用ISAR技术对常规相参雷达实现目标横向一维成像问题进行了研究,着重提出了一种基于回波相位差进行相位拟合的运动补偿方法。与以往的方法相比,这种方法具有运算量小,适用范围广等优点。 相似文献
4.
Tad M. Schmaltz 《Studies in history and philosophy of science》2003,34(4):737-762
There is considerable debate among scholars over whether Descartes allowed for genuine body–body interaction. I begin by considering Michael Della Rocca’s recent claim that Descartes accepted such interaction, and that his doctrine of the creation of the eternal truths indicates how this interaction could be acceptable to him. Though I agree that Descartes was inclined to accept real bodily causes of motion, I differ from Della Rocca in emphasizing that his ontology ultimately does not allow for them. This is not the end of the story however, since two of Descartes’s successors offered incompatible ways of developing his conflicted account of motion. I contrast the occasionalist view of Nicolas Malebranche that changes in motion derive directly from divine volitions with the non-occasionalist claim of Pierre-Sylvain Regis that such changes derive from a nature distinct from God. In light of Della Rocca’s interpretation, it is noteworthy that the issue of eternal truths is relevant to both alternative accounts. Indeed, Regis took the doctrine that such truths are created to provide crucial support for his alternative to an occasionalist account of body–body interaction. What does not help Della Rocca, however, is that Regis’s view of motion requires a fundamental revision of Descartes’s ontology. 相似文献
5.
Descartes is always concerned about knowledge. However, the Galileo affair in 1633, the reactions to his Discourse on method, and later his need to reply to objections to his Meditations provoked crises in Descartes’s intellectual development the import of which has not been sufficiently recognized. These events are the major reasons why Descartes’s philosophical position concerning how we know and what we may know is radically different at the end of his life from what it was when he began. We call this later position Descartes’s epistemic stance and contrast it with his earlier methodological, metaphysical realism. Yet Descartes’s epistemic views cannot be separated from other aspects of his work, for example, his views concerning God, causality, metaphysics, and the nature of science. A further meta-implication is that serious errors await any scholar who cites early Cartesian texts in support of late Cartesian positions, or who uses later texts in conjunction with early ones to support a reading of Descartes’s philosophy. 相似文献
6.
本文讨论了一类安全区域内的最优证券组合问题,给出了投资者为了使自己的财富在尽可能短的时间内达到预定的目标财富所应采取的最优控制策略,并且针对具体的目标财富值及金融市场参数进行了数据分析,得出了为获得既定目标财富所需平均时间的最小值. 相似文献
7.
提出了一种Motion JPEG2000可变码率编码的码率控制算法.该算法采用查找表记录存储编码帧的率失真特性,通过引入虚拟帧增加同一时刻参加码率控制帧总数,在存储容量受限条件下获得质量一致的编码序列.实验结果表明,所提出的算法能提高视觉质量、适合硬件实现和实时应用. 相似文献
8.
9.
布朗运动关于某些集首中点的分布 总被引:1,自引:0,他引:1
邹东雅 《湘潭大学自然科学学报》1988,(1)
本文根据1-维布朗运动的一些熟知结果,由高维布朗运动各分量间的独立性出发,解决了关于长方柱面、长方体表面、一对平行超平面所界带域、第一卦限、由某些正半坐标平面所围成的角域之边界等集合的首中点分布问题,然后利用布朗运动与Dirichlet-问题的联系,解决了以上集合内D-问题的求解问题。 相似文献
10.
Leibniz’s and Whitehead’s analyses of motion are at the heart of their metaphysical schemes. These schemes are to be considered as two blueprints of a similar metaphysical intuition that emerged during two breakthrough eras, that is, the 17th century and the beginning of the 20th century, and retained the Aristotelian idea that existence requires an active principle. The two philosophers’ attempts to elucidate this idea in the context of their analyses of motion still interact with central, longstanding questions in philosophy, in particular that concerning the ontological status of change. For both thinkers, the phenomenon of motion is an example par excellence, of the metaphysically fundamental principle of action that is required for change in the world. I focus on Leibniz’s and Whitehead’s similar understanding of the concept of transition that is inserted as an essential constitutive component of motion and ensures its status as something real. 相似文献