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51.
The video traffic analysis is the most important issue for large scale surveillance. In the large scale surveillance system, huge amount of live digital video data is submitted to the storage servers through the number of externally connected scalable components. The system also contains huge amount of popular and unpopular old videos in the archived storage servers. The video data is delivered to the viewers, partly or completely on demand through a compact system. In real time, huge amount of video data is imported to the viewer’s node for various analysis purposes. The viewers use a number of interactive operations during the real time tracking suspect. The compact video on demand system is used in peer to peer mesh type hybrid architecture. The chunk of video objects move fast through the real time generated compact topological space. Video traffic analytics is required to transfer compressed multimedia data efficiently. In this work, we present a dynamically developed topological space, using mixed strategy by game approach to move the video traffic faster. The simulation results are well addressed in real life scenario. 相似文献
52.
Mandal AC 《Applied ergonomics》1981,12(1):19-26
Modern furniture in schools, factories and offices is constructed in such a way that no one can use it properly. Each day people sit for many hours hunched over their tables in postures extremely harmful to the back. No one should be surprised that more than half of the population today is complaining of backache. In no other field of human activity is a similar gap between theory and reality found. A closer study of 'normal' sitting postures will explain why nobody is able to sit in the 'ideal' position. First of all, the eye in this position is at a distance of 50-60 cm from the book or working material and the axis of vision is horizontal. In addition, this posture requires at least 90 degrees flexion of the hip joint, yet the normal human being can only bend 60 degrees . A considerably better sitting posture can be obtained if the table is tilted about 10 degrees . In this way the book is brought closer and at a better angle to the eye. The worst bending of the neck is thus avoided. Furthermore, the seat can, with advantage, be tilted 20 degrees forward to reduce the flexion of the lumbar region. By both these means the extra 30 degrees flexion, which is the most strenuous part of flexion, is avoided. 相似文献
53.
Fabrication and characterization of cast Al–2Mg alloy matrix composites reinforced with short steel fibers are dealt with in the present study. Three types of steel fiber were used: uncoated, copper coated and nickel coated. All the composites were prepared by the liquid metal route using vortex methods. When tested in tension, all composites exhibited improvement in strength due to high relative strength of steel fibers. The ductility was lowered except for the composite with copper coated fibers. Copper coated fiber reinforced composites gave the highest strength. Higher strength accompanied with appreciable ductility demonstrated by composites with copper coated fibers is attributed to the solid solution and fiber strengthening as well as good bonding at the interface. Composites reinforced with uncoated and Ni coated steel fibers did not exhibit strengthening to the level exhibited with copper coated fibers because brittle intermetallic phases are formed at the interface. These phases promote initiation and facilitate propagation of cracks. The observed fracture mechanism of composites was dimple formation, fiber breakage and pullout of fibers. Fracture surface of uncoated and Ni coated composites showed extensive pull out of fibers as well as fiber breakage confirming the above inference. In case of the copper coated composites dimple formation and coalescence was more extensive. EDX analysis showed a build up Cu, Ni, and Fe at the interface. 相似文献
54.
A successful attempt to grow carbon nanotubes (CNTs) by electrodeposition technique for the first time is reported here. Carbon nanotubes were grown on Si (001) substrate using acetonitrile (1% v/v) and water as electrolyte at an applied d.c. potential ∼20 V. The films were characterized by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Raman, optical absorbance, Fourier Transform Infra Red spectroscopy (FTIR) and Electron Spin Resonance (ESR) measurements. The effect of magnetic field on the growth of nanotubes was studied critically. It was found that the presence of magnetic field during electro-deposition played a crucial role on the growth of carbon nanotubes and hence the electronic properties. Photoluminescence (PL) studies indicated band edge luminescence ∼0.72-0.83 eV. Field emission studies indicated lower turn-on voltage and higher current density for films deposited with magnetic field. 相似文献
55.
Efficient Total Chemical Synthesis of 13C=18O Isotopomers of Human Insulin for Isotope‐Edited FTIR
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Dr. Balamurugan Dhayalan Dr. Ann Fitzpatrick Dr. Kalyaneswar Mandal Dr. Jonathan Whittaker Prof. Dr. Michael A. Weiss Prof. Dr. Andrei Tokmakoff Prof. Dr. Stephen B. H. Kent 《Chembiochem : a European journal of chemical biology》2016,17(5):415-420
Isotope‐edited two‐dimensional Fourier transform infrared spectroscopy (2 D FTIR) can potentially provide a unique probe of protein structure and dynamics. However, general methods for the site‐specific incorporation of stable 13C=18O labels into the polypeptide backbone of the protein molecule have not yet been established. Here we describe, as a prototype for the incorporation of specific arrays of isotope labels, the total chemical synthesis—via a key ester insulin intermediate—of 97 % enriched [(1‐13C=18O)PheB24] human insulin: stable‐isotope labeled at a single backbone amide carbonyl. The amino acid sequence as well as the positions of the disulfide bonds and the correctly folded structure were unambiguously confirmed by the X‐ray crystal structure of the synthetic protein molecule. In vitro assays of the isotope labeled [(1‐13C=18O)PheB24] human insulin showed that it had full insulin receptor binding activity. Linear and 2 D IR spectra revealed a distinct red‐shifted amide I carbonyl band peak at 1595 cm?1 resulting from the (1‐13C=18O)PheB24 backbone label. This work illustrates the utility of chemical synthesis to enable the application of advanced physical methods for the elucidation of the molecular basis of protein function. 相似文献
56.
Awadesh Kumar Mallik Nurcan Calis Acikbas Ferhat Kara Hasan Mandal Debabrata Basu 《Ceramics International》2012,38(7):5757-5767
Two different varieties of Si3N4 powders were used to prepare SiAlON ceramics. 100% β-Si3N4 was used from refractory grade powders (B1) and another purer 98% α-Si3N4 (50A) powder was used to prepare the SiAlON samples. Since SiC + SiAlON composites reportedly perform better, batches were prepared with 15% SiC addition to the refractory powders (B1) and 17.5% SiC was added to the other SiAlON composition (50A). The samples were gas pressure sintered at 1840 °C and at 22 bar with 1 h dwelling time. Thereby, we could achieve 97–98% theoretical density. The hardness was recorded 14–17 GPa while fracture toughness varied from 4.3 to 5 MPa m1/2. Fretting experiments showed initial running-in period of 300 cycles for all the tribo-couples. After which, the steady state coefficient of frictions (COF) were achieved. Steel ball of 10 mm diameter, fretting against 50A composition, showed 0.6 average steady state COF while the same composition while fretting against alumina ball of the same diameter, showed 0.57 average steady state COF. Results have been compared with SiAlON composition derived from refractory powder (B1) and found that the 50A composition performs better under identical test conditions. Moreover, cytocompatibility study also suggests that the investigated 50A composition can be used as substrate to support cell adhesion and proliferation of L929 mouse fibroblast cell lines whereas B1 composition derived from refractory powders are toxic in nature. 相似文献
57.
Surjyanarayan Mandal Snigdha Das Mandal Krishna Chuttani Krutika K Sawant Bharat Bhushan Subudhi 《Drug development and industrial pharmacy》2016,42(8):1340-1350
Background: The present study is to investigate the neuroprotective effect of ibuprofen by intranasal administration of mucoadhesive microemulsion (MMEI) against inflammation-mediated by dopaminergic neurodegeneration in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of Parkinson’s disease (PD).Methods: Ibuprofen-loaded polycarbophil-based MMEI was developed by using response surface methodology (RSM). Ibuprofen with dose of 2.86 mg/kg/day was administered intranasally to male C57BL/6 mice for two consecutive weeks which were pre-treated with four intraperitoneal injections of MPTP (20?mg/kg of body weight) at 2?h intervals. Immunohistochemistry was performed.Results: Optimal MMEI was stable and non-ciliotoxic with 66.29?±?4.15?nm as average globule size and??20.9?±?3.98?mV as zeta potential. PDI value and transmission electron microscopy result showed the narrow globule size distribution of MMEI. The result showed that all three independent variables had a significant effect (p?<?0.05) on the responses. Rota-rod and open-field test findings revealed the significant improvement in motor performance and gross behavioral activity of the mice. The results from in vivo study and immunohistochemistry showed that nasal administration of Ibuprofen significantly reduced the MPTP-mediated dopamine depletion. Furthermore TH neurons count in the substantia nigra and the density of striatal dopaminergic nerve terminals were found to be significant higher for ibuprofen treated groups.Conclusion: Findings of the investigation revealed that Ibuprofen through developed MMEI was shown to protect neurons against MPTP-induced injury in the Substantia nigra pars compacta (SNpc) and striatum and hence, could be a promising approach for brain targeting of Ibuprofen through intranasal route to treat PD. 相似文献
58.
Nirupama Mallick Shovon Mandal Amit Kumar Singh Moumita Bishai Archana Dash 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(1):137-145
BACKGROUND: A major bottleneck in microalgal biodiesel production is lipid content, which is often low in microalgal species. The present study examines Chlorella vulgaris as a potential feedstock for biodiesel by identifying and evaluating the relationships between the critical variables that enhance the lipid yield, and characterizes the biodiesel produced for various properties. RESULTS: Factors affecting lipid accumulation in a green microalga, Chlorella vulgaris were examined. Multifactor optimization raised the lipid pool to 55% dry cell weight against 9% control. When C. vulgaris cells pre‐grown in glucose (0.7%)‐supplemented medium were transferred to the optimized condition at the second stage, the lipid yield was boosted to 1974 mg L?1, a value almost 20‐fold higher than for the control. The transesterified C. vulgaris oil showed the presence of ~82% saturated fatty acids, with palmitate and stearate as major components, thus highlighting the oxidative stability of C. vulgaris biodiesel. The fuel properties (density, viscosity, acid value, iodine value, calorific value, cetane index, ash and water contents) are comparable with the international (ASTM and EN) and Indian (IS) biodiesel standards. CONCLUSION: C. vulgaris biomass with 55% lipid content and adequate fuel properties is potentially a renewable feedstock for biodiesel. Copyright © 2011 Society of Chemical Industry 相似文献
59.
Dextrin crosslinked with poly(lactic acid): A novel hydrogel for controlled drug release application
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A new class of biodegradable crosslinked hydrogel, consisting of hydrophobic polylactic acid (PLA) and hydrophilic dextrin in presence of crosslinker N,N‐methylene bisacrylamide (MBA) has been synthesized by free‐radical polymerization technique using potassium persulfate (KPS) as initiator. By variation of crosslinker concentration, a series of hydrogels have been prepared and the optimized grade has been selected on the basis of higher crosslinking efficiency as well as lower equilibrium swelling characteristics, XRD analysis. The hydrogels have been characterized by FTIR spectra, 13C‐NMR spectra, CHN analysis, SEM analysis, swelling characteristics, and toxicity study. In vitro release study of model drugs (ciprofloxacin and ornidazole) from hydrogel matrix has been performed in various buffer solutions at 37°C. The drug release kinetics and mechanism have been studied using zero order, first‐order kinetic models, Korsemeyar–Peppas model, Higuchi model, Hixson–Crowell model, and nonlinear Kopcha model. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40039. 相似文献
60.
Nilrudra Mandal H. Roy B. Mondal N. C. Murmu S. K. Mukhopadhyay 《Journal of Materials Engineering and Performance》2012,21(1):17-24
In the light of attractive wear characteristics as well as high strength to weight ratio, extensive research on Al-based Metal
Matrix Composite (MMC) have been carried out globally in the last two decades. However, very limited research has been pursued
on tribological behavior of Al-based MMC under combined action of rolling and sliding. This study investigates the wear behavior
of 6061 Al-alloy/SiC with 10 vol.% SiCp against hardened and tempered AISI 4340 steel under combined rolling-sliding conditions. 23 factorial design of experiments have been carried out to see the effect of few parameters, i.e., contact stress, speed and
duration with respect to wear. The interaction effect has also been studied by 3D graphical contours. A mathematical model
is developed using regression analysis technique for prediction of wear behavior of the MMC and adequacy of the model has
been validated using analysis of variance (ANOVA) techniques. Finally, the optimization of parameter has also been done using
Design Expert software. The results have shown that Response Surface Methodology (RSM) is an effective tool for prediction
of wear behavior under combined sliding and rolling action. It is also found that the wear of MMC is much lower than hardened;
tempered AISI 4340 steel and rolling speed has the maximum influence in wear of both materials under investigation. 相似文献