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91.
Remote Sensing and GIS Based Approach for Identification of Artificial Recharge Sites 总被引:2,自引:1,他引:1
The main aim of this paper is to demonstrate the capabilities of Remote Sensing (RS) and Geographic Information System (GIS) techniques for the demarcation of suitable sites for artificial recharge of groundwater aquifers, in the Loni watershed, located in Unnao and Raebareli districts, Uttar Pradesh, India. In this study, the SCS-CN model, groundwater depth data and morphological parameters (bifurcation ratio, elongation ratio, drainage density, ruggedness number, relief ratio, and circulatory ratio) have been used to delineate the recharge sites for undertaking water conservation measures. Augmentation of water resource is proposed in the watershed by constructing runoff storage structures, like check dam, percolation tank and nala bund. The site suitability for these water harvesting structures is determined by considering spatially varying parameters, like runoff potential, slope, groundwater fluctuation data and morphometric information of the watershed. GIS has been used as an effective tool to store, analyse and integrate spatial and attribute information pertaining to runoff, slope, drainage, groundwater fluctuation and morphometric characteristics for such studies. 相似文献
92.
The first official shift in communication systems from fixed-location devices to portable/mobile devices happened in 1973 when Martin Cooper, general manager of Motorola's Communications Systems Division at the time, placed the first mobile call from a New York street using AT&T's network. Four years later, the first cell phone was made in Chicago with free trials offered to more than 2,000 people. The first commercial handset to receive FCC approval was Motorola's DynaTAC in 1983 [1], which was made available to the public a year later. This 1.13 kg (2.5 lb) phone that cost consumers US$3,500 was only able to achieve approximately 35 minutes of talk time and took almost 15 years to develop with the cost totaling US$100 million. 相似文献
93.
Agarwal V. Jin Sun Wang J.M. 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2009,56(4):295-299
Traditional timing-variation reduction techniques are only able to decrease gate delay variation by incurring a delay overhead. In this brief, we propose a novel and effective splitting-based variation reduction technique for gates. We developed a new tool called Timing Uncertainty Reduction by Gate Splitting (TURGS), which reduces the timing variations of a circuit and presents little delay overhead at the primary output. Our experimental results show that TURGS achieves up to 20% improvement in timing variation for gates. 相似文献
94.
Devendra Vyas Pragya JainGarima Agarwal Ankur JainI.P. Jain 《International Journal of Hydrogen Energy》2012
The effect of Cr as a catalyst in different proportions was investigated to monitor the hydrogen storage properties of Mg2Ni including their thermodynamic aspects. The P–C–T isotherms for absorption/desorption were measured at 225 °C, 250 °C, 275 °C and 300 °C temperatures. A significant increment in the plateau pressures at different temperature was observed, which shows the positive impact of Cr content in the formation of less stable hydrides. The active sites produced by the ball milling may be the reason for the formation of less stable hydrides. Decrements in the storage capacity with the Cr content were attributed to the formation of MgNi2 phase which does not absorb hydrogen at the employed temperature-pressure conditions. XRD and SEM technique were used to identify the structural and morphological changes induced by the hydrogenation cycles. 相似文献
95.
Existing perspiration-based liveness detection algorithms need two successive images (captured in certain time interval),
hence they are slow and not useful for real-time applications. Liveness detection methods using extra hardware increase the
cost of the system. To alleviate these problems, we propose new curvelet-based method which needs only one fingerprint to
detect liveness. Wavelets are very effective in representing objects with isolated point singularities, but fail to represent
line and curve singularities. Curvelet transform allows representing singularities along curves in a more efficient way than
the wavelets. Ridges oriented in different directions in a fingerprint image are curved; hence curvelets are very significant
to characterize fingerprint texture. Textural measures based on curvelet energy and co-occurrence signatures are used to characterize
fingerprint image. Dimensionalities of feature sets are reduced by running Pudil’s sequential forward floating selection (SFFS)
algorithm. Curvelet energy and co-occurrence signatures are independently tested on three different classifiers: AdaBoost.M1,
support vector machine and alternating decision tree. Finally, all the aforementioned classifiers are fused using the “Majority
Voting Rule” to form an ensemble classifier. A fingerprint database consisting of 185 real, 90 Fun-Doh and 150 Gummy fingerprints
is created by using varieties of artificial materials for casts and moulds of spoof fingerprints. Performance of the new liveness
detection approach is found very promising, as it needs only one fingerprint and no extra hardware to detect vitality. 相似文献
96.
Kantesh Balani Flavia C. Brito Lidia Kos Arvind Agarwal 《Journal of the Royal Society Interface》2009,6(40):1097-1102
Pigmentation of murine cardiac tricuspid valve leaflet is associated with melanocyte concentration, which affects its stiffness. Owing to its biological and viscoelastic nature, estimation of the in situ stiffness measurement becomes a challenging task. Therefore, quasi-static and nanodynamic mechanical analysis of the leaflets of the mouse tricuspid valve is performed in the current work. The mechanical properties along the leaflet vary with the degree of pigmentation. Pigmented regions of the valve leaflet that contain melanocytes displayed higher storage modulus (7–10 GPa) than non-pigmented areas (2.5–4 GPa). These results suggest that the presence of melanocytes affects the viscoelastic properties of the mouse atrioventricular valves and are important for their proper functioning in the organism. 相似文献
97.
Tanvi Bhasin Ashish Agarwal Sujata Sanghi R.K. Kotnala Jyoti Shah Manisha Yadav Muskaan Tuteja 《Ceramics International》2018,44(7):7629-7636
Multiferroic composites of spinel ferrite and ferroelectric xCoFe2O4 – (1-x)Na0.5Bi0.5TiO3 (with x = 0.10,0.30,0.50) were efficiently prepared by standard solid state reaction mechanism. X-ray diffractometer was used to analyze crystal structure of the prepared composites. The observed XRD patterns of the composites comprise peaks of both the phases i.e. ferrite and ferroelectric, with no sign of secondary peaks. Rietveld refinement of XRD data further confirms the coexistence of these two phases with cubic (Fd3m) and rhombohedral (R3c) symmetry corresponding to ferrite and ferroelectric phase respectively. The 3-dimensional overview of crystal structure of pure CoFe2O4 and Na0.5Bi0.5TiO3 and of composite 0.50CoFe2O4?0.50Na0.5Bi0.5TiO3 is generated by using refined parameters. The dielectric constant (ε´) and dielectric loss (tanδ) values were recorded as a function of frequency ranging from 100?Hz to 7?MHz and at different temperatures. Both ε´ and tanδ follow dispersion pattern at lower frequencies while show frequency independent behavior at higher frequencies. The magnetic evaluation carried by analyzing M-H hysteresis loop reveals the ferrimagnetic characteristics of these composites. The highest value of magnetic moment is 1.12μB observed for composite 0.50CoFe2O4 – 0.50Na0.5Bi0.5TiO3. Magnetoelectric (ME) voltage coefficient (α) was also demonstrated to observe the interaction between ferrite and ferroelectric phases. The highest value of α (72.72μV/Oe cm) is obtained for low ferrite composition 0.10CoFe2O4 – 0.90Na0.5Bi0.5TiO3, which suggests the dependence of magnetoelectric response on the resistivity of the composites. 相似文献
98.
Amit Kumar Rajendra Prasad Badoni Shailey Singhal Shilpi Agarwal Amitabh Raj Tripathi 《Chemical Engineering Communications》2018,205(1):92-101
Sulfated zirconia is a very strong solid acid catalyst which can be utilized for various reactions. The present study focuses on synthesis of zirconia-based catalyst with high acidity and high surface area, particularly for isomerization reaction. Sulfated zirconia has been obtained by sulfation of zirconia prepared by hydrothermal route. The catalyst was developed by impregnating tungstophosphoric acid on sulfated zirconia by wet incipient method. The catalyst was characterized through Brunauer–Emmett–Teller (BET) surface area, temperature-programmed desorption of ammonia, temperature program reduction of hydrogen, Fourier transmission infrared spectroscopy, and thermogravimetric analysis. The results revealed that the catalyst is crystalline in nature with surface area 190–225?m2 g?1 and acidity 0.135–0.558?mmol?g?1. Twenty-five percent conversion was obtained (as confirmed by gas chromatography) at 225°C using n-hexane as model hydrocarbon in fixed-bed microreactor. 相似文献
99.
Whole grains and resistant starch rich,reduced‐calorie biscuit diet as a hypoglycaemic,hypolipidaemic and insulin stimulator in streptozotocin‐induced diabetic rats 下载免费PDF全文
Dipesh Aggarwal Latha Sabikhi Heena Lamba Neha Chaudhary Rajeev Kapila 《International Journal of Food Science & Technology》2017,52(1):118-126
A fibre‐enriched, reduced‐calorie biscuit [formulated biscuit (FB)] was evaluated for its antidiabetic and antilipidaemic potential in streptozotocin‐induced diabetes in Wistar rats against control biscuit (CB) having high calorie and low fibre content. Animals were allocated into five groups: a control group fed with synthetic diet, two diabetes‐induced groups (CBD and FBD) and two nondiabetic groups (CBND and FBND). CBD and CBND were fed with synthetic diet + CB while FBD and FBND were fed with synthetic diet + FB. After 6 weeks of feeding, the change in weight of nondiabetic group fed with FB (+16.20%) was nonsignificantly lower compared to control (+33.01%) and CB‐fed (+34.55%) group. Nonsignificant loss in body weight was observed among diabetic group fed with FB (?11.76%) or CB (?36.88%). Feeding of FB led to a significant decrease in fasting and postprandial blood glucose levels, total cholesterol, triglycerides, LDL‐C, VLDL‐C and atherosclerotic index and increase the HDL‐C. Histological examination showed that feeding of FB was able to partially recover the destroyed β‐cell in STZ‐induced diabetic rats. 相似文献
100.
The creation of nanoscale materials for advanced structures has led to a growing interest in the area of biomineralization. Numerous microorganisms are capable of synthesizing inorganic-based structures. For example, diatoms use amorphous silica as a structural material, bacteria synthesize magnetite (Fe3O4) particles and form silver nanoparticles, and yeast cells synthesize cadmium sulphide nanoparticles. The process of biomineralization and assembly of nanostructured inorganic components into hierarchical structures has led to the development of a variety of approaches that mimic the recognition and nucleation capabilities found in biomolecules for inorganic material synthesis. In this report, we describe the in vitro biosynthesis of silver nanoparticles using silver-binding peptides identified from a combinatorial phage display peptide library. 相似文献