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81.
Multimedia Tools and Applications - Multiple-choice questions (MCQs) are used as instrumental tool for assessment, not only in various competitive examinations but also in contemporary information...  相似文献   
82.
D Dutta Majumder 《Sadhana》1986,9(2):139-156
It is well-known that one of the goals of research for the last two decades or so in pattern recognition and its sub-areas, such as processing, analysis and understanding of image, speech and natural language, and computer vision techniques etc., has always been to develop fundamental techniques for flexible interactive intelligent man-machine interfaces for computers. In this paper, the author tries to argue that for the evolution of fifth generation computer systems (FGCS) as defined by Japanese scientists, some of the things required are realisation and implementation of the advances in pattern recognition and its sub-areas, not only to achieve the man-machine interface with a natural mode of communication, but also for the realisation of the basic mechanisms of inference, association and learning, which are inherent both in pattern recognition and in the core functions of FGCS. The next generation computers will be knowledge-based systems, which form a subdomain of artificial intelligence (a1) techniques, and soa1 provides the essential link between pattern recognition domains and different application systems. No attempt is made to discuss other essential conceptual building blocks, such as software engineering, computer architecture and very large scale integration technology unless these become very relevant in the discussions of concerned topics of the paper. A section on limitations of perception, learning and knowledge for computing machines is also included. This work was funded by the Knowledge-based Computer Systems Project of the Department of Electronics, Government of India.  相似文献   
83.
Adsorption isotherms for n-hexane and methanol in mordenite and ZSM5 in the temperature range from 323 K to 473 K were found to be of type 1. The adsorbate-adsorbent interaction (C1) and adsorbate-adsorbate interaction (C2) wee computed according to Bradley and Wilkins model, whereas the Rees and Williams model predicts the adsorption characteristics. Finally, the thermodynamic parameters such as ΔGo, ΔSo, ΔHo, K, K+ have been evaluated for the sorption of n-hexane in mordenite and ZSM5.  相似文献   
84.
From the data of the 1989 Bangladesh Fertility Survey, aggregate deaths reported at ages 0-12 and 13-60 months are used to estimate infant and child mortality. Multivariate analysis shows that preceding birth interval length, followed by survival status of the immediately preceding child, are the most important factors associated with differential infant and child mortality risks; sex of the index child and mother's and father's education are also significant. Demographic factors are influential during infancy as well as childhood, but social factors, particularly mother's and father's education, now emerge as significant predictors of infant mortality risks. This indicates a change in the role of socioeconomic factors, since the earlier Bangladesh Fertility Survey in 1975.  相似文献   
85.
OBJECTIVE: The objective of this study is to present our preliminary experience with pulmonary hypertension inhaled nitric oxide therapy with two newborns presenting with transposition of the great arteries, as well as the usefulness of the Doppler in pulmonary hypertension diagnosis. PATIENTS AND METHODS: Revision of the variations of the hypoxic parameters according to the therapy and revision of the diagnostic procedures in both cases was carried out. RESULTS: Nitric oxide therapy was followed by an evident improvement of the hypoxia and the patient's hemodynamic stabilization, which allowed surgical correction in optimal conditions. The ductal flow pattern allowed recognition of the presence of pulmonary hypertension. CONCLUSIONS: Inhaled nitric oxide must be taken into account as a very useful option in the treatment of this kind of patient and the Doppler examination allows the evaluation of the presence of pulmonary hypertensions.  相似文献   
86.
An expert system for land cover classification   总被引:2,自引:0,他引:2  
A framework to represent a broad class of problems in the analysis of remote sensing imagery is proposed, and an inference engine to tackle such problems is derived. A simple model for spectral knowledge representation is used along with a method for quantification of knowledge through an evidential approach. An automatic knowledge extraction technique is also proposed to gather knowledge from training samples. The techniques of knowledge extraction, representation and inferencing have been used to do a land cover analysis on two data sets, and the results are compared with contemporary digital techniques. It is found that the proposed approach has the advantages of avoiding commission errors, and can incorporate non-spectral and collateral knowledge, while its accuracy using only spectral knowledge is comparable with standard digital methods  相似文献   
87.
This paper presents a new adaptive algorithm for dynamic load balancing on a shared BUS architecture. We present results obtained from simulation studies and queuing analysis, which reflect the relation between the BUS contention and the efficiency of load balancing. The proposed algorithm uses a scheme for monitoring theThresholdparameter to dynamically adapt itself to the limited bandwidth of the shared BUS. We have compared our algorithm with some of the known policies, and the relative performance appears to be promising.  相似文献   
88.
A new contrast enhancement technique using second-order graylevel statistics is reported here. The value of the threshold, which is required to define the graylevel transformation function, is found out depending on the average contrast between different regions. The algorithm is implemented on some images and results are shown.  相似文献   
89.
Micromechanical switches fabricated using nickel surfacemicromachining   总被引:1,自引:0,他引:1  
Micromechanical switches have been fabricated in electroplated nickel using a four-level surface micromachining process. The simplest devices are configured with three terminals, a source, a drain, and a gate and are 30 μm wide, 1 μm thick, and 65 μm long. A voltage applied between the gate and source closes the switch, connecting the source to the drain. Devices switch more than 109 cycles before failure and exhibit long-lifetime hot switching currents up to 5 mA. The initial contact resistance is less than 50 mΩ. The breakdown (stand-off) voltage between the source and the drain is greater than 100 V and the off-current is less than 20 fA at 100 V  相似文献   
90.
Properties of the Haar transform in image processing and pattern recognition are investigated. A lower bound of the performance of the Haar transform relative to that of the Karhunen-Loeve transform for first-order Markov processes is found. It is proved that the Haar transform is inferior to the Walsh-Hadamard transform for such processes. A unique condition is presented which, if satisfied by the elements of a matrix, will make the Karhunen-Loeve transform of the matrix and the Haar transform equivalent. Some fast algorithms are given to realize the diagonal elements of a Haar transformed matrix.  相似文献   
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