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71.
S. Balamurugan P. Ramasamy Yutthapong Inkong Prapun Manyum 《Materials Chemistry and Physics》2009,113(2-3):622-625
The effect of the addition of potassium chloride (KCl) in bulk growth unidirectional 〈0 0 1〉 potassium dihydrogen phosphate (KDP) grown from aqueous solution by Sankaranarayanan-Ramasamy (SR) method has been studied. The crystal of 15 mm diameter, 95 mm height was grown by SR method. Addition of 5 M% KCl in the bulk growth medium increases the quality as well as the growth rate. The grown crystals were characterized by UV–Vis spectroscopy, microhardness and dielectric studies. It reveals that the SR method grown crystalline quality and perfection is better than the conventional method grown crystal. 相似文献
72.
This paper describes a new circuit technique for designing noise-tolerant dynamic logic. It is shown that voltage scaling aggravates the crosstalk noise problem and reduces circuit noise immunity, motivating the need for noise-tolerant circuit design. In a 0.35-μm CMOS technology and at a given supply voltage, the proposed technique provides an improvement in noise immunity of 1.8×(for an AND gate) and 2.5×(for an adder carry chain) over domino at the same speed. A multiply-accumulate circuit has been designed and fabricated using a 0.35-μm process to verify this technique. Experimental results indicate that the proposed technique provides a significant improvement in the noise immunity of dynamic circuits (>2.4x) with only a modest increase in power dissipation (15%) and no loss in throughput 相似文献
73.
A 2D analytical model for transconductance, Sub-threshold current and Sub-threshold swing for Triple Material Surrounding Gate MOSFET (TMSG) is presented in this paper. Based on the solution of two dimensional Poisson equation, the physics based model of sub-threshold current of the device is derived. The model also includes the effect of gate oxide thickness and silicon thickness on the sub-threshold swing characteristics. Transconductance to drain current ratio of the triple material surrounding gate is calculated since it is a better criterion to access the performance of the device. The effectiveness of TMSG design was scrutinized by comparing with other triple material and dual material gate structures. Moreover the effect of technology parameter variations is also studied and proposed. This proposed model offers basic guidance for design of TMSG MOSFETs. The results of the analytical model are compared with the MEDICI simulation results thus providing validity of the proposed model. 相似文献
74.
Oxidative stress is a common pathogenesis of diabetes mellitus and asiatic acid (AA) plays an important role in ameliorating those difficulties. The present study was designed the protective effects of AA on altered lipid peroxidation products, enzymic and nonenzymic antioxidants in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced in experimental rats by single dose STZ (40 mg/kg b.w.) injection. Diabetic rats showed significantly increased levels of plasma glucose, thiobarbituric acid reactive substances, lipid hydroperoxides, aspartate aminotransferase, alanine aminotransferase, bilirubin, creatine kinase, urea, uric acid, creatinine and decreased levels of plasma insulin. The activities of enzymatic antioxidants such as superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferase and the levels of non-enzymatic antioxidants such as vitamin C, vitamin E and reduced glutathione were decreased in diabetic rats. Oral treatment with AA (20 mg/kg b.w.) showed near normalized levels of plasma glucose, insulin, lipid peroxidation products, enzymatic and nonenzymatic markers in diabetic rats. The results demonstrate that AA possesses potent antioxidant effect comparable with glibenclamide in improving antihyperglycemia and attenuating antioxidant status in diabetic rats. 相似文献
75.
Psychological distress and disabilities are increasingly identified among general population. Psychiatrist availability in rural areas is poor and often general practitioners have to identify and treat psychiatric problems like depression and anxiety. This work proposes a method to identify the psychiatric problems among patients using multimodel decision support system. Backpropagation neural networks (BPNN), radial basis function neural network (RBFNN) and support vector machine (SVM) models are used to design the decision support system. Forty-four factors are considered for feature extraction. The features are collected from 400 patients and divided into four sets of equal size. Three sets of patient features are used to train the decision support system and one set of patient feature are used to evaluate performance of the system. Experimental results show that the proposed method achieves an accuracy of 98.75% for identifying the psychiatric problems. 相似文献
76.
Balamurugan A Benhayoune H Kannan S Laquerriere P Michel J Balossier G Ferreira JM 《Microscopy research and technique》2008,71(9):684-688
The present study deals with the short-term physicochemical reactions at the interface between bioactive glass particles [55SiO(2)-20CaO-9P(2)O(5)-12Na(2)O-4MgO. mol%] and biological fluid (Dulbecco Modified Eagle's Medium (DMEM)). The physicochemical reactions within the interface are characterized by scanning transmission electron microscopy (TEM) (STEM) associated with Energy-dispersive X-ray spectroscopy (EDXS). Microanalysis of diffusible ions such as sodium, potassium, or oxygen requires a special care. In the present investigation the cryo-technique was adopted as a suitable tool for the specimen preparation and characterization. Cryosectioning is essential for preserving the native distribution of ions so that meaningful information about the local concentrations can be obtained by elemental microanalysis. The bioglass particles immersed in biological fluid for 24 h revealed five reaction stages: (i) dealkalization of the surface by cationic exchange (Na(+), Ca(2+) with H(+) or H(3)O(+)); (ii) loss of soluble silica in the form of Si(OH)(4) to the solution resulting from the breakdown of Si--O--Si bonds (iii); repolymerization of Si(OH)(4) leading to condensation of SiO(2)); (iv) migration of Ca(2+) and PO(4) (3-) to the surface through the SiO(2)-rich layer to form CaO-P(2)O(5) film; (v) crystallization of the amorphous CaO-P(2)O(5) by incorporating OH-- or CO(3) (2-) anions with the formation of three different surface layers on the bioactive glass periphery. The thickness of each layer is approximately 300 nm and from the inner part to the periphery they consist of Si--OH, which permits the diffusion of Ca(2+) and PO(4) (3-) ions and the formation of the middle Ca--P layer, and finally the outer layer composed of Na--O, which acts as an ion exchange layer between Na(+) ions and H(+) or H(3)O(+) from the solution. 相似文献
77.
78.
A slip-line field model for orthogonal cutting with chip breaker and flank wear has been developed. For a worn tool, this slip-line field includes a primary deformation zone with finite thickness; two secondary shear zones, one along the rake face and the other along the flank face; a predeformation zone; a curled chip; and a flank force system. It is shown that the cutting geometry is completely determined by specifying the rake angle, tool-chip interface friction and the chip breaker constraint. The chip radius of curvature, chip thickness, and the stresses and velocities within the plastic region are readily computed. Grid deformation patterns, calculated with the velocity field determined, demonstrate that the predicted effects of changes in frictional conditions at the tool-chip interface and of the rake angle on chip formation are in accord with experimental observations. The calculated normal stress distribution at the tool-chip interface is in general agreement with previously reported experimental measurements. The model proposed predicts a linear relationship between flank wear and cutting force components. The results also show that non-zero strains occur at and below the machined surface when machining with a worn tool. Severity and depth of deformation below the machined surface increases with increasing flank wear. Forces acting on the chip breaker surface are found to be small and suggest that chip control for automated machining may be feasible with other means. 相似文献
79.
Ramalingam Vinodha Sundarraj Durairaj Sakkarai Padmavathi 《International Journal of Communication Systems》2022,35(1):e5019
Due to low cost, ease of implementation and flexibility of wireless sensor networks (WSNs), WSNs are considered to be an essential technology to support the smart grid (SG) application. The prime concern is to increase the lifetime in order to find the active sensor node and thereby to find once the sensor node (SN) dies in any region. For this reason, an energy-efficient Dynamic Source Routing (DSR) protocol needs to provide the right stability region with a prolonged network lifetime. This work is an effort to extend the network's existence by finding and correcting the considerable energy leveraging behaviors of WSN. We build a comprehensive model based on real measures of SG path loss for different conditions by using the characteristics of WSN nodes and channel characteristics. This method also establishes a hierarchical network structure of balanced clusters and an energy-harvesting SN. The cluster heads (CHs) are chosen by these SN using a low overhead passive clustering strategy. The cluster formation method is focused on the use of passive clustering of the particle swarm optimization (PSO). For the sake of eliminating delayed output in the WSN, energy competent dynamic source routing protocol (EC-DSR) is used. Chicken swarm optimization (CSO) in which optimum cluster path calculation shall be done where distance and residual energy should be regarded as limitation. Finally, the results are carried out with regard to the packet distribution ratio, throughput, overhead management, and average end-to-end delay to demonstrate the efficiency of the proposed system. 相似文献
80.
Hameed Abdul Zubar Ramasamy Balamurugan Shahzad Muhammad Atif Bakhsh Ahmed Atef S. 《The Journal of supercomputing》2021,77(9):10117-10137
The Journal of Supercomputing - In this article, the clinical decision support system is discussed under the weighted fuzzy rule approach and genetic algorithm for computer-aided heart disease... 相似文献