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31.
A multimedia database query consists of a set of fuzzy and boolean (or crisp) predicates, constants, variables, and conjunction, disjunction, and negation operators. The fuzzy predicates are evaluated based on different media criteria, such as color, shape, layout, keyword. Since media-based evaluation yields similarity values, results to such a query is defined as an ordered set. Since many multimedia applications require partial matches, query results also include tuples which do not satisfy all predicates. Hence, any fuzzy semantics which extends the boolean semantics of conjunction in a straight forward manner may not be desirable for multimedia databases. In this paper, we focus on the problem of ‘given a multimedia query which consists of multiple fuzzy and crisp predicates, how to provide the user with a meaningful overall ranking.’ More specifically, we study the problem of merging similarity values in queries with multiple fuzzy predicates. We describe the essential multimedia retrieval semantics, compare these with the known approaches, and propose a semantics which captures the retrieval requirements in multimedia databases. Received 13 August 1999 / Revised 13 May 2000 / Accepted in revised form 26 July 2000  相似文献   
32.
In this paper, we present the ARIA media processing workflow architecture that processes, filters, and fuses sensory inputs and actuates responses in real-time. The components of the architecture are programmable and adaptable; i.e. the delay, size, and quality/precision characteristics of the individual operators can be controlled via a number of parameters. Each data object processed by qStream components is subject to transformations based on the parameter values. For instance, the quality of an output data object and the corresponding processing delay and resource usage depend on the values assigned to parameters of the operators in the object flow path. In Candan, Peng, Ryu, Chatha, Mayer (Efficient stream routing in quality- and resource-adaptive flow architectures. In: Workshop on multimedia information systems, 2004), we introduced a class of flow optimization problems that promote creation and delivery of small delay or small resource-usage objects to the actuators in single-sensor, single-actuator workflows. In this paper, we extend our attention to multi-sensor media processing workflow scenarios. The algorithms we present take into account the implicit dependencies between various system parameters, such as resource consumption and object sizes. We experimentally show the effectiveness and efficiency of the algorithms.
Kyung Dong RyuEmail:
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33.
A method for the time suboptimal control of an industrial manipulator from an initial position and orientation to a final position and orientation as it moves along a specified path is proposed. Nonlinear system equations that describe the manipulator motion are linearized at each time step along the path. A method which gives the control inputs (joint angular velocities) for time suboptimal control of the manipulator is developed. In the formulation, joint angular velocity and acceleration limitations are also taken into consideration. A six degree of freedom elbow type manipulator is used in numerical examples to verify the method developed.  相似文献   
34.
The objective of this study is to explore the groundwater availability for agriculture in the Musi basin. Remote sensing data and geographic information system were used to locate potential zones for groundwater in the Musi basin. Various maps (i.e., base, hydrogeomorphological, geological, structural, drainage, slope, land use/land cover and groundwater prospect zones) were prepared using the remote sensing data along with the existing maps. The groundwater availability of the basin is qualitatively classified into different classes (i.e., very good, good, moderate, poor and nil) based on its hydrogeomorphological conditions. The land use/land cover map was prepared for the Kharif season using a digital classification technique with the limited ground truth for mapping irrigated areas in the Musi basin. The alluvial plain in filled valley, flood plain and deeply buried pediplain were successfully delineated and shown as the prospective zones of groundwater.  相似文献   
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36.
Superalloys are used in aggressive atmospheres in aero-engines and land-base gas turbines. IN738LC is an important superalloy used in gas turbines. Strengthening Ni3(Al,Ti,Nb) type precipitate phase in this superalloy goes through size and morphological changes with time and temperature. Experimental observations suggest precipitate motion as a whole in the matrix leading to agglomeration of nearby precipitates for coarsening, which is in contrast to the traditional Ostwald ripening. Likewise, contrary to the conventionally accepted view of constant activation energy, experimental data in this study indicate varying activation energy, which causes coalescence and relates to the precipitate size in the form of an increasing polynomial.  相似文献   
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38.
The circular duct between the cylinder and displacer serves as a regenerator in free-piston Stirling engines. The cylinder wall is fixed and the displacer wall is in reciprocating motion during the steady operation of the engine. The basic equations of the working fluid and regenerative duct are derived using the Lagrangian method in terms of the displacement of the displacer, so that time does not appear in the equations. A relation is derived between the cylinder and displacer wall temperatures to obtain the initial wall temperature distributions. A computer program is written in and the governing equations, which include the pressure fluctuations due to the flow reversals, are solved numerically using a finite difference method. The results and discussion are presented.  相似文献   
39.
First-principle calculations have been carried out on the structural, electronic, elastic, and phonon properties of the full-Heusler alloys X2YAl (X = Co, Fe and Y = Cr, Sc). The calculations predict that the Fe2CrAl and Co2CrAl are half-metallic ferromagnets at the equilibrium lattice constant with a minority-spin energy gap of 0.2912 and 0.668 eV, respectively. Fe2ScAl exhibit a gap in the majority density of states, with a few states at the Fermi level and about 0.217 states eV?1, unlike the other Heusler compounds; due to this, it is considered a false half metal, and Co2ScAl is considered a non-magnetic compound. The elastic constants were derived from the slopes of the acoustic branches in the phonon-dispersion curve. The calculated lattice constants, bulk modulus, and first-order pressure derivative of the bulk modulus are reported for the L21 structure and compared with previous values. Phonon-dispersion curves were obtained using the first-principle linear-response approach of the density-functional perturbation theory. The specific heat capacity at a constant volume C V of X2YAl (X = Co, Fe and Y = Cr, Sc) alloys is calculated and discussed.  相似文献   
40.
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