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101.
Song Kiryong Kim Jungsoo Kim Doyoon Yoo Junghwan Rieh Jae-Sung 《Journal of Infrared, Millimeter and Terahertz Waves》2020,41(2):202-214
Journal of Infrared, Millimeter, and Terahertz Waves - In this work, a 300-GHz 7?×?7 detector array based on a 65-nm Si CMOS technology has been developed and transmission imaging... 相似文献
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Eun-Jung Lee Jae-Sung Kwon Soo-Hyuk Uhm Doo-Hoon Song Yong Hee Kim Eun Ha Choi Kyoung-Nam Kim 《Current Applied Physics》2013
Titanium (Ti) is a primary material used for dental implants, and the sandblasted, large-grit, and acid-etched (SLA) surface treatment is commonly used on titanium to promote early osseointegration. Despite their benefits, SLA-treated Ti surfaces are disadvantaged by their hydrophobic property, and much research has been performed to address this problem. In current study, we hypothesized the effects of a nitrogen-based non-thermal atmospheric pressure plasma jet (NTAPPJ) treatment on SLA-treated Ti would increase hydrophilicity and cellular activity. Samples with and without the NTAPPJ treatment were analyzed using a field emission scanning electron microscope, optical surface roughness system, X-ray photoelectron spectroscope, and water contact angle measuring system. MC3T3-E1 cells (murine osteoblastic cell line) attachments and proliferations were examined by the MTT and BrdU colorimetry assay. Cell immunofluorescent microscopic images were observed by a confocal laser scanning microscope for a morphological analysis. This study found that the nitrogen-based NTAPPJ treatment on SLA-treated Ti significantly increased the hydrophilicity and MC3T3-E1 cell attachments and proliferations. Hence, it was concluded that an additional procedure of nitrogen-based NTAPPJ treatment just prior to implantation of SLA-treated Ti into oral defect sites could improve the success of dental implant surgery. 相似文献
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A. Jagannathan 《The European Physical Journal B - Condensed Matter and Complex Systems》2012,85(2):68
We describe some of the properties of 2d quantum quasiperiodic antiferromagnets as reported in studies that have been carried
out in the last decade. Many results have been obtained for perfectly ordered as well as for disordered two dimensional bipartite
quasiperiodic tilings. The theoretical methods used include spin wave theory, and renormalization group along with Quantum
Monte Carlo simulations. These methods all show that the ground state of these unfrustrated antiferromagnets have Néel type
order but with a highly complex spatial distribution of local staggered magnetization. The ground state properties, excitation
energies and spatial dependence, structure factor, and local susceptibilities are presented and discussed. The effects of
introducing geometrical disorder on the magnetic properties are discussed. 相似文献
107.
Behdis Eslamnour S. Jagannathan Maciej J. Zawodniok 《International Journal of Wireless Information Networks》2011,18(4):295-308
Single-channel based wireless networks have limited bandwidth and throughput and the bandwidth utilization decreases with
increased number of users. To mitigate this problem, simultaneous transmission on multiple channels is considered as an option.
In this paper, we propose a distributed dynamic channel allocation scheme using adaptive learning automata for wireless networks
whose nodes are equipped with single-radio interfaces. The proposed scheme, Adaptive Pursuit learning automata runs periodically
on the nodes, and adaptively finds the suitable channel allocation in order to attain a desired performance. A novel performance
index, which takes into account the throughput and the energy consumption, is considered. The proposed learning scheme adapts
the probabilities of selecting each channel as a function of the error in the performance index at each step. The extensive
simulation results in static and mobile environments provide that the proposed channel allocation schemes in the multiple
channel wireless networks significantly improves the throughput, drop rate, energy consumption per packet and fairness index—compared
to the 802.11 single-channel, and 802.11 with randomly allocated multiple channels. Also, it was demonstrated that the Adaptive
Pursuit Reward-Only (PRO) scheme guarantees updating the probability of the channel selection for all the links—even the links
whose current channel allocations do not provide a satisfactory performance—thereby reducing the frequent channel switching
of the links that cannot achieve the desired performance. 相似文献
108.
Anuradha Jagannathan Michel Duneau 《The European Physical Journal B - Condensed Matter and Complex Systems》2014,87(7):1-10
Network theory is increasingly employed to study the structure and behaviour of social, physical and technological systems — including civil infrastructure. Many of these systems are interconnected and the interdependencies between them allow disruptive events to propagate across networks, enabling damage to spread far beyond the immediate footprint of disturbance. In this research we experiment with a model to characterise the configuration of interdependencies in terms of direction, redundancy, and extent, and we analyse the performance of interdependent systems with a wide range of possible coupling modes. We demonstrate that networks with directed dependencies are less robust than those with undirected dependencies, and that the degree of redundancy in inter-network dependencies can have a differential effect on robustness depending on the directionality of the dependencies. As interdependencies between many real-world systems exhibit these characteristics, it is likely that many such systems operate near their critical thresholds. The vulnerability of an interdependent network is shown to be reducible in a cost effective way, either by optimising inter-network connections, or by hardening high degree nodes. The results improve understanding of the influence of interdependencies on system performance and provide insight into how to mitigate associated risks. 相似文献
109.
Archer SJ Camac DM Wu ZJ Farrow NA Domaille PJ Wasserman ZR Bukhtiyarova M Rizzo C Jagannathan S Mersinger LJ Kettner CA 《Chemistry & biology》2002,9(1):79-92
NMR spectroscopy was used to characterize the hepatitis C virus (HCV) NS3 protease in a complex with the 24 residue peptide cofactor from NS4A and a boronic acid inhibitor, Ac-Asp-Glu-Val-Val-Pro-boroAlg-OH. Secondary-structure information, NOE constraints between protease and cofactor, and hydrogen-deuterium exchange rates revealed that the cofactor was an integral strand in the N-terminal beta-sheet of the complex as observed in X-ray crystal structures. Based upon chemical-shift perturbations, inhibitor-protein NOEs, and the protonation state of the catalytic histidine, the boronic acid inhibitor was bound in the substrate binding site as a transition state mimic. In the absence of cofactor, the inhibitor had a lower affinity for the protease. Although the inhibitor binds in the same location, differences were observed at the catalytic site of the protease. 相似文献
110.
R. Jagannathan 《International Journal of Theoretical Physics》1983,22(12):1105-1121
A finite-dimensional analog of Weyl's formulation of quantum kinematics of a physical system through irreducible Abelian groups of unitary ray rotations in system space offers many possibilities for the quantum mechanics of confined particles. This paper is devoted to the expansion of the recently developed framework of such Weylian finite-dimensional quantum mechanics which may provide a new way of thinking about the characteristics of quark physics. 相似文献