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121.
Omid E Kia David S Doermann Azriel Rosenfeld Rama Chellapa 《Computer Vision and Image Understanding》1998,70(3):335-349
In this paper, we describe a compression and representation scheme which exploits the component-level redundancy found within a document image. The approach identifies patterns which appear repeatedly, represents similar patterns with a single prototype, stores the location of pattern instances, and codes the residuals between the prototypes and the pattern instances. Using a novel encoding scheme, we provide a representation that facilitates scalable lossy compression and progressive transmission and supports document image analysis in the compressed domain. We motivate the approach, provide details of the encoding procedures, report compression results, and describe a class of document image understanding tasks that operate on the compressed representation. 相似文献
122.
Gelinas U.J. Jr. Rama D.V. Skelton T.M. 《Professional Communication, IEEE Transactions on》1996,39(3):135-145
The paper describes the implementation of a learning community involving a technical communication course and an accounting course. Students are simultaneously registered in all the courses constituting the learning community. The learning community approach to writing instruction can be viewed as one way to implement writing across the curriculum with the following distinguishing features. First, students are registered simultaneously for both courses; the communication skills taught in one course are simultaneously reinforced in another course. Second, the faculty of the two courses interact extensively to deliver skills (e.g., communication skills) in a coherent manner across the two courses. We describe the development of a theoretical framework for connecting the two courses. This theoretical framework guided implementation decisions such as the choice of communication skills to be covered in the accounting course, the design of assignments, and the design of evaluation criteria. While we focus on the integration of an accounting course with a communication course, the learning community approach and the implementation steps are applicable to other disciplines 相似文献
123.
EC Bass NA Duncan JS Hariharan J Dusick HU Bueff JC Lotz 《Canadian Metallurgical Quarterly》1997,22(24):2867-2876
STUDY DESIGN: A biomechanical study of the compressive creep behavior of the porcine intervertebral disc before and after frozen storage. OBJECTIVE: To determine whether frozen storage alters the creep response, hydration, and nuclear swelling pressure of the intact intervertebral disc. SUMMARY OF BACKGROUND DATA: The mechanical response of the disc is dominated by swelling and fluid flow, whose effects are time-dependent. Because fluid content, which may change during storage, plays a significant role in the disc's time-dependent behavior, changes in mechanical response due to freezing may have been missed in previous studies that focused on time-independent behavior only. METHODS: Porcine intervertebral discs were tested in repeated cycles of compressive creep either immediately postmortem or after 3 weeks of frozen storage. Swelling pressure and nuclear hydration were also measured in fresh and frozen discs. A fluid transport model was used to analyze the creep data. RESULTS: The creep behavior of the intact porcine intervertebral disc is dramatically affected by frozen storage. The apparent permeability of the frozen discs was 82% higher than that of the fresh discs, and the swelling pressure of frozen discs was 25% lower in frozen discs (P < 0.01). The behavior of fresh and frozen discs became more dissimilar with repeated cycles of creep. CONCLUSIONS: In vitro tests of frozen porcine intervertebral discs do not represent fresh behavior. Frozen storage appears to permanently alter disc behavior. The precise nature of any freezing-induced damage, and whether frozen storage similarly affects human discs, remains to be seen. 相似文献
124.
Om Parkash P. Ganguly G.Rama Rao C.N.R. Rao D.S. Rajoria V.G. Bhide 《Materials Research Bulletin》1974,9(9):1173-1176
Catalytic activities of rare earth cobaltites and related compounds are shown to be related to the spin and valence states of cobalt. 相似文献
125.
The need for a computerised information system for handpumps installed in any state is brought out. A system with organisational
and software aspects is presented. The organisational aspect covers the generation and transmission of data on handpumps at
the users’ and the government level. The software consists of a Fortran program, data files, an updating program and a transaction
file. The periodic updating of data files is discussed. The system output covers many items of vital information needed for
formulating maintenance and research and development policies. A test run of the program with an arbitrarily selected data
base is discussed. 相似文献
126.
The performance of packed bed adiabatic gas absorbers has been analyzed using the enthalpy and material balance equations incorporating a new parameter, fr, defined as the fraction of the heat of absorption that is accounted for in the gas stream. An experimental programme to evaluate fr was carried out and the data correlated. It was found that fr was dependent on the thermo-physical properties and the hydrodynamic conditions. It is postulated that the mechanism by which this heat transfer occurs is by turbulence at the interface and by entrainment. 相似文献
127.
128.
129.
After formulation of the various dynamical and kinematical relations connecting the flow quantities with the geometrical parameters of the streamline trajectories, the expressions for the tangent, principal normal and binormal vectors and the curvature and torsion of the streamlines have been obtained in terms of the velocity components, pressure, density, thermal conductivity and radiation variables. This is followed by the determination of the pressure gradient along the streamlines, their principal normals and binormals. It has been shown that the radiating character of the gas decreases the pressure gradient whereas thermal conductivity increases it along the streamlines but the pressure remains constant along the binormals and if the streamlines are straight lines, the trajectories of the principal normals lie on the surface of the constant pressure. Finally, the expressions for the vorticity components in terms of the curvature of the streamline and the velocity gradients along the streamline, their principal normals and binormals have been obtained. 相似文献
130.
K. V. Masrani H. S. Rama S. L. Bafna 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1974,24(6):331-341
The u.v. absorption spectra of forty-one substituted coumarins have been studied in methanol and aqueous methanol over a pH range. The effect of the nature and position of the substituent in the coumarin nucleus is discussed. 相似文献