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91.
Abstract Error-diffused quantization has been applied to the generation of cell-oriented computer-generated Fourier transform holograms, resulting in reduced reconstruction errors. Improvements are demonstrated when applied to the algorithms of Lohmann, Lee and Burckhardt after invoking realistic constraints on the minimum size of the printable spot for an electrophotographic laser printer. 相似文献
92.
Akila Swaminathan Sree Rama Chaitanya Sridhara Swaraj Sinha Shunmugam Nagarajan Uma Maheswari Balaguru Jamila H Siamwala Saranya Rajendran Uttara Saran Suvro Chatterjee 《Journal of food science》2012,77(12):H273-H279
Abstract: Recent evidence has demonstrated that nitrites play an important role in the cardiovascular system. Fennel (Foneiculum vulgare) seeds are often used as mouth fresheners after a meal in both the Indian sub‐continent and around the world. The present study aims to quantify the nitrite and nitrates in fennel seeds as well as elucidating the effect of fennel derived‐nitrites on vascular functions. Results from our study show that fennel seeds contain significantly higher amount of nitrites when compared to other commonly used post‐meal seeds. Furthermore our study confirmed the functional effects of fennel derived‐nitrites using in vitro and ex vivo models that describe the promotion of angiogenesis, cell migration, and vasorelaxation. We also showed that chewing fennel seeds enhanced nitrite content of saliva. Thus our study indicates the potential role of fennel derived‐nitrites on the vascular system. Practical Application: This study is focused on determining the effect of fennel‐derived nitrites on angiogenesis (the formation of new blood vessels from pre‐existing ones), cell migration, and vasorelaxation (dilation of blood vessels) thereby preserving cardiovascular health. 相似文献
93.
R. Nagarajan Anupam Mukherjee A. Roy M. V. Khire 《International journal of remote sensing》2013,34(4):573-585
Spatial and temporal multi-layered information is required to assess landslide hazard susceptibility. The manual method of data integration for targeting potential zones susceptible to landslide hazard is time consuming. The present study highlights the utility of temporal remotely-sensed data and knowledgebased Geographical Information Systems for collection, integration and analysis of spatially-oriented data, as well as in finding out the inherent relation between separate entities in parts of West ghat in India. 相似文献
94.
95.
Nagarajan Sridhar DDL Chung W. A. Anderson J. Coleman 《Journal of Electronic Materials》1995,24(10):1451-1459
Plasma Physics Corporation, P.O. Box 548, Locust Valley, NY 11650 The changes in enthalpy and entropy due to hydrogen evolution
in hydrogenated amorphous silicon films were measured by differential scanning calorimetry (DSC). Hydrogen evolution was associated
with an endothermic DSC peak, as supported by thermogravimetric analysis and evolved gas analysis. The en-thalpy and entropy
changes of hydrogen evolution increased with heating rate and hydrogen content, because the evolution involved not only Si-H
bond breaking, but also defect formation (such as Si-Si bond breaking), which was enhanced by a high flow of evolving hydrogen.
In contrast, the activation energy of hydrogen evolution was controlled by the doping rather than the hydrogen content, because
doping affected the Si-H bonding, which in turn affected the state before hydrogen evolution. Crystallization, which occurred
at tempera-tures higher than hydrogen evolution, was delayed for the amorphous silicon film in a higher disordered state after
hydrogen evolution, suggesting that hydrogen content influenced the crystallization process. 相似文献
96.
97.
Miyano S. Numata K. Sato K. Yabe T. Wada M. Haga R. Enkaku M. Shiochi M. Kawashima Y. Iwase M. Ohgata M. Kumagai J. Yoshida T. Sakurai M. Kaki S. Yanagiya N. Shinya H. Furuyama T. Hansen P. Hannah M. Nagy M. Nagarajan A. Rungsea M. 《Solid-State Circuits, IEEE Journal of》1995,30(11):1281-1285
An 8 Mb embedded DRAM has been developed. The salient feature of this embedded DRAM is page fault tolerance. Accessing across different pages can be performed using a minimum column cycle. This feature is achieved by placing a data latch and a transfer gate between the bit line sense amplifier and the column select gate. This DRAM can be reconfigured as separated 2 Mb units when it is embedded as a macro cell of an ASIC library 相似文献
98.
The maximum possible intrinsic modulation bandwidth in semiconductor lasers is conventionally written in terms of the K factor. Although this is often sufficient in bulk lasers, it is usually not true in quantum well lasers where carrier transport can significantly affect the high speed properties. Analytical expressions are presented, which include the effects of carrier transport, for the modulation response and the relative intensity noise in quantum well lasers. It is shown that in the presence of significant transport effects, the K factor is not an accurate measure of the maximum possible intrinsic modulation bandwidth.<> 相似文献
99.
Composite ZrO2−SiO2 powders were prepared using a gel route. Morphological and crystallographic features of ZrO2 particles formed during the heat treatment, and the particle sizes of the composites have been investigated. The following
polymorphic changes have been observed during the heat treatment: amorphous → metastable-cubic/tetragonal ZrO2 → tetragonal ZrO2 → monoclinic ZrO2. SiO2 crystallizes above 1273K. The martensitic transformation of ZrO2 (t → m) was observedin situ, when exposed to a high-energy electron beam. These results are important in the production of ZrO2-toughened ceramics of controlled microstructure. 相似文献
100.
On optimal call admission control in cellular networks 总被引:10,自引:0,他引:10
Two important Quality-of-Service (QoS) measures for current cellular networks are the fractions of new and handoff “calls”
that are blocked due to unavailability of “channels” (radio and/or computing resources). Based on these QoS measures, we derive
optimal admission control policies for three problems: minimizing a linear objective function of the new and handoff call
blocking probabilities (MINOBJ), minimizing the new call blocking probability with a hard constraint on the handoff call blocking
probability (MINBLOCK) and minimizing the number of channels with hard constraints on both of the blocking probabilities (MINC).
We show that the well-known Guard Channel policy is optimal for the MINOBJ problem, while a new Fractional Guard Channel policy
is optimal for the MINBLOCK and MINC problems. The Guard Channel policy reserves a set of channels for handoff calls while
the Fractional Guard Channel policy effectively reserves a non-integral number of guard channels for handoff calls by rejecting
new calls with some probability that depends on the current channel occupancy. It is also shown that the Fractional policy
results in significant savings (20-50\%) in the new call blocking probability for the MINBLOCK problem and provides some,
though small, gains over the Guard Channel policy for the MINC problem. Further, we also develop computationally inexpensive
algorithms for the determination of the parameters for the optimal policies.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献