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排序方式: 共有1195条查询结果,搜索用时 15 毫秒
61.
Noriah Bidin Siti Radhiana Azni Shumaila Islam Mundzir Abdullah M. Fakaruddin Sidi Ahmad Ganesan Krishnan A. Rahman Johari M. Aizat A. Bakar Nur Syahirah Sahidan NurFatin Musa M. Farizuddin Salebi Naqiuddin Razali Mohd Marsin Sanagi 《International Journal of Hydrogen Energy》2017,42(26):16325-16332
Hydrogen production via water electrolysis was studied under the effect of magnetic and optical field. A diode solid state laser at blue, green and red were utilized as optical field source. Magnetic bar was employed as external magnetic field. The green laser has shown a greatest effect in hydrogen production due to its non-absorbance properties in the water. Thus its intensity of electrical field is high enough to dissociation of hydronium and hydroxide ions during orientation toward polarization of water. The potential to break the autoprotolysis and generate the auto-ionization is the mechanism of optical field to reveal the hydrogen production in water electrolysis. The magnetic field effect is more dominant to enhance the hydrogen production. The diamagnetic property of water has repelled the present of magnetic in water. Consequently the water splitting occurs due to the repulsive force induced by the external magnetic field. The magnetic distributed more homogenous in the water to involve more density of water molecule. As a result hydrogen production due to magnetic field is higher in comparison to optical field. However the combination both fields have generated superior effect whereby the hydrogen yields nine times higher in comparison to conventional water electrolysis. 相似文献
62.
Sorption of elemental mercury by activated carbons 总被引:1,自引:0,他引:1
63.
Sree Hari Krishnan Parthasarathi R. Padmanabhan Hema A. Murthy 《International Journal of Speech Technology》2011,14(4):361-368
This paper demonstrates the robustness of group delay based features to additive noise. First, we analytically show the robustness
of group delay based representations. The analysis makes use of the fact that, for minimum-phase signals, the group delay
function can be represented in terms of the cepstral coefficients of the log-magnitude spectrum. Such a representation results
in the speech spectrum dominating over the noise spectrum, both at low and high SNRs. Further, we experimentally demonstrate
the robustness of the representation on a voice activity detection (VAD) task, comparing a group delay based VAD algorithm
with standard VAD methods as well as a magnitude-spectrum based method. 相似文献
64.
L. Satyanarayan Anish Kumar T. Jayakumar C. V. Krishnamurthy Krishnan Balasubramaniam Baldev Raj 《Journal of Nondestructive Evaluation》2009,28(3-4):111-124
New techniques developed using the array transducer, to image and size the bottom-surface and near-through-wall crack-like defects in thick carbon steel components are discussed. Three studies are reported here including (a) Optimal beam steering angle for focused and unfocused inspection using phased array method for bottom-surface crack sizing. (b) A front wall correction algorithm for sizing of near-through-wall crack-like defects. (c) A small aperture technique for sizing of near-through-wall crack-like defects. A Finite Difference Time Domain (FDTD) based simulation was used to study and verify the experimental observations. The application of time domain scheme relative arrival time technique (RATT), to measure the size of the near-through wall crack-like defects for the leak before break (LBB) criterion, was also investigated and found to be insufficient. A conventional SAFT algorithm was used for improving the sizing using the small aperture technique. 相似文献
65.
We present transmission electron microscopy observations of domain wall motion in thin freestanding KNbO 3 crystals under applied electric fields. Since there is no substrate, there is no elastic clamping of 90 domains. We observe that curved and tilted 90 domain walls are the most mobile, whereas untilted 90 domain walls are resistant to field-induced motion. We explain this result in terms of two factors. First, the switching pressure on a domain wall ( P 2 m P 1 ) E is determined by the relative electrostatic energies of the neighboring polarizations P 1 and P 2 . Consequently, some 90 domain walls are immobile under certain field directions, leading to domain interlocking. Second, domain walls experiencing a high switching pressure move by a ripple mechanism, and do not move as rigid sheets. The tilted wall region in such a ripple has a polarization charge, and an associated depolarization field, which reduces the local switching barrier. An accumulation of polarization charge can result in a tilted or curved wall, as occurs at the mobile tips of 90 domain needles. Any increase in density of immobile wall configurations with cycle time represents an inherent contribution to fatigue. Uniaxial ferroelectrics, with polarizations parallel to the field, should not experience such domain interlocking. 相似文献
66.
67.
Krishnan R. Arumugan R. Lindsay J.F. 《Industry Applications, IEEE Transactions on》1988,24(3):456-461
Some of the design aspects of the switched-reluctance motor for nonservo applications are considered. Towards this objective, a step-by-step procedure is developed for the design of switched-reluctance motors 相似文献
68.
Krishnan R. Stefanovic Victor R. Lindsay James F. 《Industry Applications, IEEE Transactions on》1983,(1):94-104
Efficient use of an inverter-fed induction motor drive necessitates a knowledge of the characteristics of the induction motor from a " control" point of view. The characteristics of both the voltage -and the current-source inverter-fed induction motor drive are investigated, neglecting the filter time constants in the link and feedback loops. Of particular interest is the role played by the voltage/current and frequency inputs. Their effects on variables that are not often discussed such as torque angle, stator real power, airgap flux- linkages and stator and rotor voltages/currents are studied. A by- product of this aspect of the study leads to the nature of feedback signals and their suitability for control purposes. It is also found that the link filter has little effect on relative suitability of these signals. A study of the current source induction motor drive dynamics for torque angle feedback is included. 相似文献
69.
Shapiro Stewart; Lindsey Charles; Krishnan H. Shanker 《Canadian Metallurgical Quarterly》2006,12(4):251
When market changes alter what product attributes are deemed important, consumers may intentionally try to forget old product information in an attempt to remember new product information. In Experiment 1, the authors demonstrated that intentional forgetting of this nature temporarily inhibits retrieval of old product information and leads to a benefit to memory for new product information. The results show that, after a short delay, benefits continue in the absence of costs, which is supportive of a multiple-process account of intentional forgetting. Experiment 2 extends these effects using an advertising message to stimulate forgetting. Across both experiments, results also show that brand preference is based on learning of new attribute information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
The popular and well-tested software process frameworks such as the Software Engineering Institute's Capability Maturity Model and ISO 9001, details key process areas for software development. Focusing more on continuous improvement in code development processes, generic-process frameworks such as the CMM lack key process areas (KPA) that address capabilities for managing distributed software projects, such as establishing mutual knowledge and managing geographically dispersed social networks. We identify 24 new KPAs that address the wide-ranging capabilities needed for managing distributed software development and arrange them in an evolutionary order similar to the CMM framework. The evolutionary or phased approach in improving software management capabilities helps firms systematically assess their situations and plan for improvements. We also report the results of a statistically tested maturity assessment survey and test the overall rigor of our model against industry expert opinion and objective data collected from real-world projects implemented at SAP AG, a leading global-enterprise software firm. 相似文献