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1.
The present study attempts quantitative determination of changes in the morphological surface features viz. fractal dimension, lower and upper cut off length scale through Power Spectral Density analysis prior to and after irradiation of 100 KeV Ar+ ion beam at incidence angles of 0°, 40° and 60° on ZnO thin films. All the unirradiated and irradiated samples are subjected to photoelectrochemical characterization and a correlation between photoelectrochemical performance and morphological parameters is established. Sample irradiated at 40° angle at the fluence of 5 × 1016 ions/cm2 is found to possess maximum fractal dimension of 2.72, lower and upper cut off length scale of 3.16 nm and 63.00 nm respectively. This sample exhibits maximum photocurrent density of 3.19 mA/cm2 and applied bias photon-to-current efficiency of 1.12% at 1.23 V/RHE. Hydrogen gas collected for duration of 1 h for the same sample was ~4.83 mLcm?2.  相似文献   
2.
Neural Computing and Applications - We propose “Deep Autoencoders for Feature Learning in Recommender Systems,” a novel discriminative model based on the incorporation of features from...  相似文献   
3.
4.
Human faces undergo considerable amounts of varialions with aging. While face recognition systems have been proven to be sensitive to factors such as illumination and pose, their sensitivity to facial aging effects is yet to be studied. How does age progression affect the similarity between a pair of face images of an individual? What is the confidence associated with establishing the identity between a pair of age separated face images? In this paper, we develop a Bayesian age difference classifier that classifies face images of individuals based on age differences and performs face verification across age progression. Further, we study the similarity of faces across age progression. Since age separated face images invariably differ in illumination and pose, we propose preprocessing methods for minimizing such variations. Experimental results using a database comprising of pairs of face images that were retrieved from the passports of 465 individuals are presented. The verification system for faces separated by as many as nine years, attains an equal error rate of 8.5%.  相似文献   
5.
The introduction of high spatial and spectral resolution sensors on-board remote-sensing spacecraft has increased, by orders of magnitude, the data rates which need to be sustained on the down-link or cross-link transmission channels. Since these channels are severely limited in capacity, the need arises to perform on-board compression to reduce the volume of data which would need to be down-linked. This paper discusses the development and refinement of a low complexity lossy spectral/spatial compression method which provides high compression ratios at low levels of distortion. The developed techniques uses pixels in adjacent bands to predict the intensity of pixels in the band being compressed via a simple linear prediction model. This prediction method when combined with a low-distortion discrete cosine transform (DCT) block coding method yields performance comparable to block-adaptive Karhunen-Loeve Transform (KLT)-DCT methods without incurring the complexity penalty of the KLT. The methods' performance suffers under misregistration. A fractional-pixel interpolation enhancement to the basic technique significantly improves the performance in the case of misregistered bands  相似文献   
6.
A critical review of the current status of tungsten resources, of state-of-the-art processing technology and of product development in India vis-a-vis the world scenario is presented. An attempt has been made to identify technology gap areas requiring attention.  相似文献   
7.
To convey the dynamic information related to traffic conditions in various parts of a city, we propose an environment utilizing the technology of smart phones to provide information anywhere and anytime. Called ";The Interactive Traffic Beat Project,"; it uses a Web-based service to deliver this information to people through their cell phones at the right time so that valuable time can be saved and the chaos on the roads can be managed.  相似文献   
8.
Al-Li alloys being developed as lighter, substitutes for conventional high strength Al alloys are to be processed by routine methods. During extrusion of a 8090 Al-Li alloy, the extrusion die container failed causing some alarm. This failed die container was analysed to examine if the failure was caused by interaction of Li diffusing out of Al-Li alloy with the carbides of die steel. The evidence, although not conclusive, is sufficient to exercise caution during such processing.  相似文献   
9.
There is a need for developing low cost, easily and abundantly available, yet efficient, adsorbents for the removal of phosphates during the tertiary treatment of wastewaters. The tamarind nut shell activated carbon (TNSAC) prepared on a laboratory scale has been used to evaluate its performance for phosphate adsorption. This paper describes the laboratory production of this adsorbent material in its various forms, and discusses the effects of the TNSAC process variables (the unrinsed and rinsed forms of the TNSAC and the impregnation ratio) on its performance in adsorbing phosphate. The material has been shown to be a good alternative adsorbent. As much as 95% phosphate removal by the unrinsed TNSAC is possible in about 30 min under the test conditions. The phosphate adsorbing capacity is about two times higher for the unrinsed TNSAC in comparison to the rinsed TNSAC. The adsorption rates, however, transit to extremely low rates towards the end when equilibrium conditions could be attained in about 2 h contact time. The phosphate removal mechanics are adsorption and precipitation/ion exchange when unrinsed TNSAC is used, and adsorption alone for the rinsed TNSAC. The maximum phosphate removal is found to take place at an impregnation ratio of 1.0 for both forms of the TNSAC.  相似文献   
10.
The problem of transporting constant-bit-rate (CBR) traffic through a packet network is analyzed. In the system considered, CBR traffic is packetized and packets from several similar sources are multiplexed on a transmission link. The bit streams are recreated at the receiving end by demultiplexing the packets and then playing out the packets of each CBR stream. Traffic fluctuations may cause gaps to appear in the playout process. Their frequency can be reduced by adding a smoothing delay to each stream. The queueing system analyzed has periodic arrivals and deterministic service times. A method of analysis, based on the ballot theorems of Takacs (1967), is presented to provide steady-state delay distributions as well as a transient analysis of the system to predict the statistics of the time for a gap to develop in the CBR stream as a function of the smoothing delay  相似文献   
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