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61.
W. Debski 《勘探地球物理进展》1996,(5)
随偏移距数据变化的地震振幅包含地层弹性参数的信息。由于反演问题的一般解包括所有可能的地层模型空间内的概率信息,我们研究了用AVO获得的概率值选择弹性参数的可行性。对数据中的信息作合适的分析需要对概率作明确的定义,此概率确定了不同弹性参数的总的未知状态(地震速度、 相似文献
62.
63.
霍戈文钢铁公司6号高炉在1992年6~11月进行了喷煤比190kg/t铁的试验,11~12月进行了210kg/t铁的试验,试验中发现要控制炉料水分和稳定煤气流,并要采取适当的休风措施,以稳定炉况。喷煤比从130kg/t铁提高到210kg/t铁,要求适当提高鼓风含量,由22.5%提高到26.5%。 相似文献
64.
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66.
ATM技术开创了基于远程教学的课程设计新纪元。高速数据连接使得对集中式多媒体业务的访问成为可能,会议电视的应用使用户能够参加现场直播的研讨会、讲座和解说。 远程教学课程设计所面临的主要问题是,要适当地补偿教学双方分离而造成的交互性损失。对教育学的研究表明,积累知识的过程在相当程度上有赖于学员间的相互交流。ATM技术能为学员间建立起多种现场交互型连接。 相似文献
67.
68.
Kielczynski PJ Pajewski W Szalewski M 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1990,37(1):38-43
Ring piezoelectric transducers generating ultrasonic energy in air were designed and tested experimentally and numerically. The radiation pattern of the transducer is very narrow (4 degrees ) and its frequency response has a broadband character. Resonant frequencies of the transducers were determined experimentally and verified theoretically. Applications of the proposed ring transducers in a robotic ranging system were examined. 相似文献
69.
Shin-Ting W Yasuda CL Cendes F 《IEEE transactions on visualization and computer graphics》2012,18(2):299-308
Curvilinear reformatting of 3D magnetic resonance imaging data has been recognized by the medical community as a helpful noninvasive tool for displaying the cerebral anatomy. It consists of automatically creating, with respect to a reference surface, a series of equidistant curvilinear slices at progressively deeper cuts. In comparison with planar slices, it allows more precise localization of lesions and identification of subtle structural abnormalities. However, current curvilinear reformatting tools either rely on the time-consuming manual delineation of guiding curves on 2D slices, or require costly automatic brain segmentation procedures. In addition, they extract the skin and skull, impeding a precise topographic correlation between the location of the brain lesion and skin surface. This impairs planning of craniotomy for neurosurgery, and of the appropriate implantation of electrodes for intracranial electroencephalography in presurgical evaluation. In this work, we present a novel approach based on direct manipulation of the visualized volume data. By using a 3D painting metaphor, the reference surface can be defined incrementally, according to the principle that the user interacts with what she/he sees. As a response, an animation of the reformatting process is displayed. The focus of this paper is a new volume tagging algorithm behind user interactions. It works at an interactive frame rate on current graphics hardware. 相似文献
70.
Pedrycz W Bargiela A 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2012,42(3):582-590
Clustering forms one of the most visible conceptual and algorithmic framework of developing information granules. In spite of the algorithm being used, the representation of information granules-clusters is predominantly numeric (coming in the form of prototypes, partition matrices, dendrograms, etc.). In this paper, we consider a concept of granular prototypes that generalizes the numeric representation of the clusters and, in this way, helps capture more details about the data structure. By invoking the granulation-degranulation scheme, we design granular prototypes being reflective of the structure of data to a higher extent than the representation that is provided by their numeric counterparts (prototypes). The design is formulated as an optimization problem, which is guided by the coverage criterion, meaning that we maximize the number of data for which their granular realization includes the original data. The granularity of the prototypes themselves is treated as an important design asset; hence, its allocation to the individual prototypes is optimized so that the coverage criterion becomes maximized. With this regard, several schemes of optimal allocation of information granularity are investigated, where interval-valued prototypes are formed around the already produced numeric representatives. Experimental studies are provided in which the design of granular prototypes of interval format is discussed and characterized. 相似文献