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991.
A fast progressive image transmission scheme using block truncation coding by pattern fitting 总被引:2,自引:0,他引:2
Bibhas Chandra Dhara Bhabatosh Chanda 《Journal of Visual Communication and Image Representation》2012,23(2):313-322
In this paper, we have proposed a novel progressive image transmission scheme. In the present method, the concept of the BTC-PF is used for faster decoding. Here, images are decomposed into a number of blocks based on smoothness criterion. The smooth blocks are encoded by block means and the others are by BTC-PF method. To encode a block by BTC-PF method, the codebook is organized like a full search progressive transmission tree which helps greatly in efficient progressive transmission. The present method provides good image quality at low bit-rate and faster decoding compared to other spatial domain progressive transmission methods. We extend this method for color images also. In color image coding, each color plane is encoded separately and then the encoded information of the planes are transmitted in interleaving manner to obtain color images right from the early stages. 相似文献
992.
Dipak Samanta Jayanta Kumar Bag Chanchal Kumar De Abhijit Chandra 《International Journal of Communication Systems》2021,34(1):e4671
Efficient spectrum utilization is a promising technique for a prolonged unused radio frequency (RF) spectrum in a wireless network. In this paper, an adaptive spectrum sharing cognitive radio (CR) network has been proposed consisting of a primary user (PU) and secondary user transmitter (SU ? Tx) that communicates with secondary user receiver (SU ? Rx) via multiantenna‐based proactive decode‐and‐forward (DF) relay selection scheme. In our model, strategically an adaptable joint venture on underlay/overlay protocol is defined based on channel occupancy using spectrum sensing technique. Here, secondary transmitters (i.e., source transmitter) continuously sense the PU activities by energy detector and can simultaneously transmit to secondary receivers. Depending on sensing result secondary transmitters automatically switches in underlay mode if PU is active otherwise operates in overlay mode. The advantage of this scheme is that the joint mode of transmission allows the SUs to maximize their transmission rate. The outage performance at SU ? Rx and closed‐form expressions of joint underlay/overlay protocol has been evaluated. The power control policies at different transmitter nodes are taken care of. With the same diversity order, a trade‐off between multiantenna and multirelay is shown. This comparison shows improvement in outage behavior when the count in relays surpasses the number of antennas. Finally, the analytical model of smart efficient spectrum utilization without harming license users in CR is validated by MATLAB simulation. 相似文献
993.
Chandra Shekhar S. De Sirkar S.D. Deo K.V.S. Hanumantha Rao S. Srivastava N.B. Chakravarty 《Microelectronics Reliability》1987,27(1)
The need for an LSI chip for interfacing data acquisition and conversion devices to a VME bus are highlighted. The functions of such an interface chip in a data acquisition subsystem are explained. The architecture, the design considerations and the novel features of the chip, designed at CEERI, Pilani, are discussed and the floor plan and specifications are indicated. 相似文献
994.
Abhijit Chandra Grant Anderson Shreyes Melkote Wei Gao Han Haitjema Konrad Wegener 《CIRP Annals》2014,63(2):797-819
Solar cells gained significant interest recently due to the rapid increase in fossil fuel costs and renewed attention to sustainability. The effectiveness of a solar cell in energy harvesting hinges on three key characteristics: efficiency of energy conversion, reliability and life expectancy, and cost. All three attributes are critically influenced by surface and interface properties inherent in the design and manufacture of these devices. This paper starts with an exposition of solar cell manufacturing, followed by discussion of efficiency enhancement, reliability issues, and cost and energy footprint reduction. The role of surface and interface modifications in realizing such improvements is assessed. 相似文献
995.
Arbaz Khan Pravir Dutt Chandra Shekhar Upadhyay 《Journal of scientific computing》2017,73(2-3):876-905
In this paper, a least-squares spectral element method for parabolic initial value problem for two space dimension on parallel computers is presented. The theory is also valid for three dimension. This method gives exponential accuracy in both space and time. The method is based on minimization of residuals in terms of the partial differential equation and initial condition, in different Sobolev norms, and a term which measures the jump in the function and its derivatives across inter-element boundaries in appropriate fractional Sobolev norms. Rigorous error estimates for this method are given. Some specific numerical examples are solved to show the efficiency of this method. 相似文献
996.
Molecular identification and characterization of Fusarium spp. associated with sorghum seeds 下载免费PDF全文
997.
The development of tissue engineering in the field of orthopedic surgery is booming. Two fields of research in particular have emerged: approaches for tailoring the surface properties of implantable materials with osteoinductive factors as well as evaluation of the response of osteogenic cells to these fabricated implanted materials (hybrid material). In the present study, we chemically grafted insulin onto the surface of hydroxyapatite nanorods (nHA). The insulin-grafted nHAs (nHA-I) were dispersed into poly(lactide-co-glycolide) (PLGA) polymer solution, which was electrospun to prepare PLGA/nHA-I composite nanofiber scaffolds. The morphology of the electrospun nanofiber scaffolds was assessed by field emission scanning electron microscopy (FESEM). After extensive characterization of the PLGA/nHA-I and PLGA/nHA composite nanofiber scaffolds by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectrometry (EDS), and transmission electron microscopy (TEM), the PLGA/nHA-I and PLGA/nHA (used as control) composite nanofiber scaffolds were subjected to cell studies. The results obtained from cell adhesion, alizarin red staining, and Von Kossa assay suggested that the PLGA/nHA-I composite nanofiber scaffold has enhanced osteoblastic cell growth, as more cells were proliferated and differentiated. The fact that insulin enhanced osteoblastic cell proliferation will open new possibilities for the development of artificial scaffolds for bone tissue regeneration. 相似文献
998.
Sarkar Bitan Kumar Kumar Nikhil Dey Rajib Das Gopes Chandra 《Metallurgical and Materials Transactions B》2018,49(4):1822-1833
Metallurgical and Materials Transactions B - In the present study, a unique method is adopted to achieve higher reducibility of titaniferous magnetite lump ore (TMO). In this method, TMO is... 相似文献
999.
The biogenic amines tyramine, putrescine, cadaverine, 2-phenylethylamine, histamine and tryptamine were determined in 13 kinds of alcoholic beverages produced in Taiwan. They were derivatised with dansyl chloride and analysed using a high-performance liquid chromatographic method. Total amine content ranged from 0.23 to 11.4 μg ml?1 with Charng Chuen liqueur containing the highest level and Mei Kwei Lu the lowest. Tryptamine was found in all samples in amounts between 0.01 and 1.79 μg ml?1. The levels of the other five amines in the tested samples were 0-7.0 μg ml?1 for 2-phenylethylamine, 0-3.0 μg ml?1 for putrescine, 0-2.9 μg ml?1 for cadaverine, 0-4.5 μg ml?1 for histamine, and 0-1.4 μg ml?1 for tyramine. These levels seem unlikely to have adverse effects on human health. 相似文献
1000.
A. Chandra 《Energy Conversion and Management》1988,28(4):275-276
The effect of seed on the break down of the insulating wall has been considered using a simple model. It has been shown that evaporation of the seed from the wall improves its electrical insulation. 相似文献