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41.
42.
P. M. Prasad T. R. Mankhand P. Surya Prakash Rao S. N. Singh A. J. K. Prasad 《Metallurgical and Materials Transactions B》2002,33(3):345-354
Kinetic studies were conducted on the carbon monoxide reduction of molybdenite in the presence of lime. Contrary to the expectation
that the MoS2 (s)+CaO (s)+CO (g) reaction will result in metal formation, molycarbide was found to form and no Mo was detected in the product.
This is explained on the basis of thermochemical considerations, which indicate that the Mo2C formation is more feasible by eight orders of magnitude. The effects of quantity of lime in the charge, CO flow rate, temperature
(1123 to 1298 K), and time of reduction have been studied. Kinetic analysis reveals that the results on the MoS2 (s) conversion to Mo2C (s) fit into a modified parabolic rate law. Based on the thermochemical calculations and experimental findings, the probable
reaction scheme has been identified. Molycarbide appears to form by a three-successive solid-gas reaction path consisting
of (1) metal formation by the MoS2 (s)+CO (g) reaction followed by (2) in-situ carburization of Mo metal by CO (g), and finally (3) the scavenging of the COS (g) by lime, resulting in CaS (s). The latter
two reactions drive the overall reaction forward. Further, out of these three consecutive reactions, progress of the overall
MoS2+CaO+CO reaction seems to be governed by the intrinsic kinetics of the first one. Calcium molybdate, which forms as a transitory phase, plays a significant role by modifying the linear
kinetics of the MoS2 (s)+CO (g) to one of parabolic nature. 相似文献
43.
Depth from defocus: A spatial domain approach 总被引:12,自引:1,他引:11
A new method named STM is described for determining distance of objects and rapid autofocusing of camera systems. STM uses image defocus information and is based on a new Spatial-Domain Convolution/Deconvolution Transform. The method requires only two images taken with different camera parameters such as lens position, focal length, and aperture diameter. Both images can be arbitrarily blurred and neither of them needs to be a focused image. Therefore STM is very fast in comparison with Depth-from-Focus methods which search for the lens position or focal length of best focus. The method involves simple local operations and can be easily implemented in parallel to obtain the depth-map of a scene. STM has been implemented on an actual camera system named SPARCS. Experiments on the performance of STM and their results on real-world planar objects are presented. The results indicate that the accuracy of STM compares well with Depth-from-Focus methods and is useful in practical applications. The utility of the method is demonstrated for rapid autofocusing of electronic cameras. 相似文献
44.
Ping Yan Patrice Batamack G. K. Surya Prakash George A. Olah 《Catalysis Letters》2005,103(3-4):165-168
Gallium triflate catalyzed Beckmann rearrangement is described. Various aliphatic or aromatic amides are obtained from the corresponding ketoximes in good yields. Gallium triflate exhibits high catalytic activity for a wide variety of substrates. 相似文献
45.
Concurrent design of manufacturing cell and control functions: A neural network approach 总被引:1,自引:1,他引:0
Dr F. Frank Chen Surya Raju Sagi 《The International Journal of Advanced Manufacturing Technology》1995,10(2):118-130
This paper presents a neural network based decision support system (DSS) for use in concurrently determining cell configuration, operation plans, and complexity requirements of cell control functions. Advanced simulators and neural network technology are used in developing the DSS. Simulation experiments were conducted with many possible combinations of design changes to generate training pairs for a neural network. Complexity of cell control functions required by each design option was assessed, based on operational requirements, and was used to train another neural net. Once both neural networks are properly trained, one network can be used to predict the cell design configuration given a set of desirable cell performance measures, while the other network can be used to identify complexity requirements of the cell control functions by using the output provided by the first network as input to the second neural net. An operation-driven cell design methodology was applied to sequentially predict requirements of both cell configuration and cell control functions from the trained neural networks. This innovative new design methodology was illustrated via a successful implementation exercise in acquiring a real automated manufacturing cell at industrial settings. The exercise proves that such a DSS serves well as an effective tool for cell designers and the management in determining appropriate cell configuration and cell control functions at the design stage. 相似文献
46.
Reddy S. Narasimha Dumpala Surya Rao Sarna Sushil K Northcott Peter G. 《IEEE transactions on bio-medical engineering》1981,(10):696-701
An application of statistical pattern recognition technique to the classification of canine duodenal contractile activity resulting from the ingestion of three different test meals, viz. water, acid, and solid, is described. Feature vectors were extracted from the contractile activities recorded by means of strain gauges, and were based on average duration, number, and intensities of contractions, as well as their frequency and propagational characteristics. Pattern training and classification were performed via the Bayes decision rule. The resuits indicate that the three different meals give rise to three different kinds of contractile activities. An improvement in the classifier's performance was observed when it was updated with correctly classified patterns. The results appear to suggest that pattern analysis techniques add a new dimension to the study of gastrointestinal motility in health and disease. For example, pattern recognition techniques can also be extended to identify contractile patterns altered due to such pathological conditions as irritable bowel syndrome and postoperative diarrhea and, hence, elucidate the underlying relationship between contractile activity and distal propulsion of contents. 相似文献
47.
Face recognition on mobile devices, such as personal digital assistants and cell phones, is a big challenge owing to the limited computational resources available to run verifications on the devices themselves. One approach is to transmit the captured face images by use of the cell-phone connection and to run the verification on a remote station. However, owing to limitations in communication bandwidth, it may be necessary to transmit a compressed version of the image. We propose using the image compression standard JPEG2000, which is a wavelet-based compression engine used to compress the face images to low bit rates suitable for transmission over low-bandwidth communication channels. At the receiver end, the face images are reconstructed with a JPEG2000 decoder and are fed into the verification engine. We explore how advanced correlation filters, such as the minimum average correlation energy filter [Appl. Opt. 26, 3633 (1987)] and its variants, perform by using face images captured under different illumination conditions and encoded with different bit rates under the JPEG2000 wavelet-encoding standard. We evaluate the performance of these filters by using illumination variations from the Carnegie Mellon University's Pose, Illumination, and Expression (PIE) face database. We also demonstrate the tolerance of these filters to noisy versions of images with illumination variations. 相似文献
48.
The Integrated Computer Aided Manufacturing (ICAM) program of the U.S. Air Force identified a need to better communicate and analyze manufacturing for the people involved in improving productivity. To satisfy that need, the ICAM program developed the IDEF (ICAM Definition) method to address particular characteristics of manufacturing. This IDEF method is equally applicable in analyzing other types of organizations. IDEF comprises three modeling methodologies: function model methodology (IDEF0), information model methodology (IDEF1) and dynamics model methodology (IDEF2). This paper reports on the Information model methodology only. This methodology is used to construct an information model that helps in understanding the structure of information needed to support the functions of an organization. 相似文献
49.
Ajaya Kumar Singh Bhawana Jain Reena Negi Yokraj Katre Surya Prakash Singh Virender K. Sharma 《Catalysis Letters》2009,131(1-2):98-104
Kinetics of Ruthenium(III) [Ru(III)] chloride catalyzed oxidation of valine (Val) has been studied by N-bromophthalimide (NBP) in the acidic medium at 35 °C. The reaction rate follows first-order and zero-order dependence with respect to [NBP] and [Val]. First-order kinetics was observed for Ru(III) chloride at low range of concentrations and tending towards zero-order at higher concentrations. A negative effect was observed for [H+] and [phthalimide], while a positive effect was observed for [Cl?] on the reaction rate. Hg(OAc)2, ionic strength (I), and dielectric constant (D) of the medium did not change significantly the reaction rate. The rate constants as a function of temperature (298–318 K) were used to calculate activation parameters of the oxidation of Val by NBP. A plausible mechanism was proposed to explain the results of kinetic studies, reaction stoichiometry and product analysis. 相似文献
50.
Anand J. Puppala Pinit Ruttanaporamakul Surya Sarat Chandra Congress 《Geotextiles and Geomembranes》2019,47(3):295-305
This paper presents a research study on a bridge site located along US highway 67 over SH 174 in Cleburne, Texas, where bridge approach slabs have experienced more than 0.4 m (17 in.) of settlement within a span of 16 years after construction. Many treatment methods attempted to mitigate this problem had proven to be ineffective. As part of novel rehabilitation works, the top of existing fill soil on the embankment was replaced with lightweight expanded polystyrene (EPS) geofoam blocks to alleviate the approach slab settlements. This paper describes initial design and construction details of the rehabilitation works performed on the embankment system along with a focus on the early performance details. Field monitoring studies were conducted for almost three years to study the bump/settlements under the EPS geofoam embankment system. Short term measured settlement data was analyzed with hyperbolic model to predict the long term settlements. Numerical finite element studies attempted in this study showed that settlements could be reasonably predicted by modeling these geofoam embankments. Based on the monitoring and modeling studies, the effectiveness of utilizing EPS geofoam as an embankment fill material was addressed to mitigate the differential settlements under a bridge approach slab. 相似文献