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991.
992.
Hypsometric Integral Estimation Methods and its Relevance on Erosion Status of North-Western Lesser Himalayan Watersheds 总被引:7,自引:0,他引:7
Assessment of erosion status of a watershed is an essential prerequisite of integrated watershed management. This not only
assists in chalking out suitable soil and water conservation measures to arrest erosion and conserve water but also helps
in devising best management practices to enhance biomass production in watersheds. The geologic stages of development and
erosion proneness of the watersheds are quantified by hypsometric integral. The estimation of hypsometric integral is carried
out from the graphical plot of the measured contour elevation and encompassed area and by using empirical formulae. In this
study, efforts were made to estimate the hypsometric integral values of the Sainj and Tirthan watersheds and their sub watersheds
in the Lesser Himalayas using four different techniques, and to compare the procedural techniques of its estimation and relevance
on erosion status. It was revealed that the hypsometric integral calculated by elevation–relief ratio method was accurate,
less cumbersome and easy to calculate within GIS environment. Also comparison of these hypsometric integral values revealed
that the Sainj watershed (0.51) was more prone to erosion than the Tirthan watershed (0.41). Further, the validation of these
results with the recorded sediment yield data of 24 years (1981–2004) corroborated that the average annual sediment yield
during this period for Sainj watershed (0.53 Mt) was more than that of the Tirthan watershed (0.3 Mt). Thus, the hypsometric
integral value can be used as an estimator of erosion status of watersheds leading to watershed prioritization for taking
up soil and water conservation measures in watershed systems. 相似文献
993.
Sholom M. Weiss Robert J. Baseman Fateh Tipu Christopher N. Collins William A. Davies Raminderpal Singh John W. Hopkins 《Applied Intelligence》2010,33(3):318-329
We describe an automated system for improving yield, power consumption and speed characteristics in the manufacture of semiconductors.
Data are continually collected in the form of a history of tool usage, electrical and other real-valued measurements—a dimension
of tens of thousands of features. Unique to this approach is the inference of patterns in the form of binary regression rules
that demonstrate a significantly higher or lower performance value for tools relative to the overall mean for that manufacturing
step. Results are filtered by knowledge-based constraints, increasing the likelihood that empirically validated rules will
prove interesting and worth further investigation. This system is currently installed in the IBM 300 mm fab, manufacturing
game chips and microprocessors. It has detected numerous opportunities for yield and performance improvement, saving many
millions of dollars. 相似文献
994.
MM Sheehan E Stanley GF Fitzgerald D van Sinderen 《Canadian Metallurgical Quarterly》1999,65(2):569-577
A lysis module encoded by the temperate bacteriophage phiO1205 was identified. This lysis module contains a lysin gene, designated lyt51, and two putative holin-encoding genes, designated lyt49 and lyt50. lyt51 encodes a lytic enzyme specifically directed against streptococcal cell walls. Similar to other phage-encoded lysins, Lyt51 appears to have a modular design in which the N-terminal portion corresponds to its enzymatic activity while the C-terminal region is responsible for its substrate binding specificity. The two putative holin-encoding genes, lyt49 and lyt50, located immediately upstream of lyt51, were identified on the basis of their homology to other identified holin-encoding genes. Expression of lyt49 or lyt50 in Escherichia coli was shown to cause cell death and leakage of the intracellular enzyme isocitrate dehydrogenase into the growth medium without apparent lysis of the cells. Southern blotting experiments demonstrated that at least one of the three components of the identified lysis module is present in all members of a large collection of bacteriophages, indicating that components of this lysis module are widespread among bacteriophages infecting Streptococcus thermophilus. 相似文献
995.
Urchin-like p-type ZnO nanorods were grown along preferred (100) direction by low temperature solution technique and subjected to morphological, structural, Hall conductivity, dielectric and ferroelectric characterization. Hall voltage, bulk carrier density (hole) and mobility were found to be 0.058 V, 2.36 × 1019 cm−3 and 0.025 cm2/V s, respectively. In the temperature variation of the dielectric constant a phase transition at 343 K was observed at various frequencies. The piezoelectric charge coefficient (d33) was found to be 1.60 pC/N. In the ferroelectric hysteresis loop studies, ZnO exhibited remnant polarization and coercive field at 0.083 µC/cm2 and 3.86 kV/cm, respectively. 相似文献
996.
Ranimol Stephen A. M. Siddique Fouran Singh Lekshmi Kailas Seno Jose Kuruvilla Joseph Sabu Thomas 《应用聚合物科学杂志》2007,105(2):341-351
The effect of microfillers on the thermal stability of natural rubber (NR), carboxylated styrene butadiene rubber (XSBR) latices, and their 70/30 NR/XSBR blend were studied using thermogravimetric method. Microcomposites of XSBR and their blend were found to be thermally more stable than unfilled samples. The activation energy needed for the degradation of polymer chain was calculated from Coats‐Redfern plot. Activation energy needed for the thermal degradation of filled samples was higher than unfilled system. It indicated the improved thermal stability of the filled samples. The ageing resistance of the micro‐filled samples was evaluated from the mechanical properties of aged samples. The thermal ageing was carried out by keeping the samples in hot air oven for 7 days at 70°C. The mechanical properties such as tensile strength, modulus at 300% elongation, and strain at break were computed. As compared to unfilled samples, micron‐sized fillers reinforced systems exhibited higher ageing resistance. Finally, an investigation was made on the influence of ion‐beam irradiation on microcomposites of NR, XSBR latices, and their 70/30 blend systems using 28Si8+ performed at 100 MeV. The surface changes of the samples after irradiation were analyzed using X‐ray photoelectron spectroscopy. The results of XPS measurements revealed that the host elements were redistributed without any change in binding energies of C1s, O1s, and Si2p. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
997.
Analyzing the Structure and Evolution of Massive Telecom Graphs 总被引:2,自引:0,他引:2
Nanavati A.A. Singh R. Chakraborty D. Dasgupta K. Mukherjea S. Das G. Gurumurthy S. Joshi A. 《Knowledge and Data Engineering, IEEE Transactions on》2008,20(5):703-718
With the ever-growing competition in telecommunications markets, operators have to increasingly rely on business intelligence to offer the right incentives to their customers. Existing approaches for telecom business intelligence have almost solely focused on the individual behavior of customers. In this paper, we use the call detail records of a mobile operator to construct call graphs, that is, graphs induced by people calling each other. We determine the structural properties of these graphs and also introduce the Treasure-Hunt model to describe the shape of mobile call graphs. Moreover, we determine how the structure of these call graphs evolve over time. Finally, since short messaging service (SMS) is becoming a preferred mode of communication among many sections of the society, we study the properties of the SMS graph. Our analysis indicates several interesting similarities and differences between the SMS graph and the corresponding call graph. We believe that our analysis techniques can allow telecom operators to better understand the social behavior of their customers and potentially provide major insights for designing effective incentives. 相似文献
998.
Mikhail M. Feldstein Tatiana I. Kiseleva Galina N. Bondarenko Julia V. Kostina Parminder Singh Gary W. Cleary 《应用聚合物科学杂志》2009,112(3):1142-1165
Mechanisms of molecular interaction in the blends of a polybase, a copolymer of N,N‐dimethylaminoethylmethacrylate with methylmethacrylate and butylmethacrylate (PDMAEMA–MMA/BMA), with a polyacid, a copolymer of methacrylic acid with ethylacrylate (PMAA‐co‐EA), and plasticizer, triethylcitrate (TEC), have been investigated with FTIR Spectroscopy and potentiometry. To evaluate the strengths of hydrogen and ionic bonds in the polyelectrolyte complexes, quantum‐chemical calculations were performed. According to this analysis, the energy of ionic and hydrogen bonding diminishes in the order: multi‐component complexes involving protonated aminogroup of DMAEMA (ammonium cation) in the presence of chlorine counterion with ionized or unchanged carboxyl groups and water molecules (690–520 kJ/mol) > ternary H‐bonded acid‐base complexes associated with molecule of water (520–420 kJ/mol) > binary ionic complex of carboxylate anion and ammonium cation (404 kJ/mol) > H‐bonded complex of carboxylate and ammonium ions (257 kJ/mol) > binary H‐bonded complex of uncharged carboxyl group with ammonium cation (114 kJ/mol) > ternary H‐bonded complex of uncharged carboxyl group, aminogroup and water molecule (43 kJ/mol) > binary H‐bonded complex between nonionized carboxyl and amino groups (26 kJ/mol). Proton‐donating capability of functional groups in the studied polyelectrolyte blends diminishes in the order: HN+(CH3)2 ? > HOOC? > HO? . The proton‐donating capacity can be significantly improved in the presence of Cl? ions, the effect of which may be appreciably inhibited if Na+ cations are available in the blend or solution. Proton‐accepting capability weakens in the order: uncharged aminogroup > carboxylate anion > uncharged carboxyl group > hydroxyl group. The results of quantum chemical calculations facilitate interpretation of FTIR spectra. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
999.
In this work, the annular (tangential) flow of Newtonian and non‐Newtonian fluids in tube bundles has been studied experimentally. Extensive pressure drop data has been obtained embracing wide ranges of the Reynolds number (13–6600) and for two test modules of different geometrical arrangements, but of similar overall void fraction. Preliminary experiments suggest that the pressure drop is mainly determined by the overall void fraction of the bundle and is relatively insensitive to the detailed geometrical configuration of the bundle. A simple predictive correlation has been developed which reconciles the present results for Newtonian and power law fluids with acceptable levels of reliability. 相似文献
1000.
Narendra Kumar Kuldeep Bauddh Sanjeev Kumar Neetu Dwivedi D. P. Singh S. C. Barman 《Clean Technologies and Environmental Policy》2013,15(6):1033-1039
Bioavailability of heavy metals present in industrial sludges and their subsequent phytotoxicity are crucial parameters to assess the associated health hazards and suitability for land application. The present study is an effort to determine the extractability of heavy metals present in different phases of the sludges, coming out of two different operations involved in petrochemical industry viz. spent caustic treatment (SCT) and waste water treatment (WWT) following the BCR sequential extraction procedure. The maximum amount of Cd and Cu was found associated with oxidizable phase, whereas Cr and Ni were best recovered in residual fractions of both the sludges. Maximum Pb was recovered in oxidizable and residual phase in the WWT and SCT sludges, respectively. The stabilization treatment undergone by sludges strongly influenced the heavy metal distribution and the phases to which they were associated. The total metal concentration in both the sludges did not exceed the limit set out by the European Legislation and was found as Cd = 0.449, Pb = 3.340, Ni = 6.530, Cr = 21.087, & Cu = 27.129 μg g?1 and Cd = 0.549, Pb = 5.664, Ni = 7.161, Cr = 27.096, & Cu = 35.479 μg g?1 in the SCT and WWT sludges, respectively. Phytotoxicity of the sludges was assessed against the germination index and the relative root and shoot growth. Sludge leachates did not adversely affect the seed germination and the early seedling growth of Mung (Phaseolus mungo) and Gram (Cicer arietinum), indicating that these metals were concentrated in the non-bioavailable fractions of sludges. 相似文献