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991.
spBayes: An R Package for Univariate and Multivariate Hierarchical Point-referenced Spatial Models 总被引:1,自引:0,他引:1
Scientists and investigators in such diverse fields as geological and environmental sciences, ecology, forestry, disease mapping, and economics often encounter spatially referenced data collected over a fixed set of locations with coordinates (latitude-longitude, Easting-Northing etc.) in a region of study. Such point-referenced or geostatistical data are often best analyzed with Bayesian hierarchical models. Unfortunately, fitting such models involves computationally intensive Markov chain Monte Carlo (MCMC) methods whose efficiency depends upon the specific problem at hand. This requires extensive coding on the part of the user and the situation is not helped by the lack of available software for such algorithms. Here, we introduce a statistical software package, spBayes, built upon the R statistical computing platform that implements a generalized template encompassing a wide variety of Gaussian spatial process models for univariate as well as multivariate point-referenced data. We discuss the algorithms behind our package and illustrate its use with a synthetic and real data example. 相似文献
992.
We report a deep submicron vertical PMOS transistor using strained Si1-xGex channel formed by Ge ion implantation and solid phase epitaxy. These vertical structure Si1-xGex /Si transistors can be fabricated with channel lengths below 0.2 μm without using any sophisticated lithographic techniques and with a regular MOS process. The enhancement of hole mobility in a direction normal to the growth plane of strained Si1-xGex over that of bulk Si has been experimentally demonstrated for the first time using this vertical MOSFET. The drain current of these vertical MOS devices has been found to be enhanced by as much as 100% over control Si devices. The presence of the built-in electric field due to a graded SiGe channel has also been found to be effective in further enhancement of the drive current in implanted-channel MOSFET's 相似文献
993.
Thermoelectric performance of electrodeposited nanostructured polyaniline doped with sulfo‐salicylic acid 下载免费PDF全文
Krishanu Chatterjee Mousumi Mitra Saibal Ganguly Kajari Kargupta Dipali Banerjee 《应用聚合物科学杂志》2014,131(4)
Conducting polymers, in present days, are considered to be potential thermoelectric (TE) materials. Among them polyaniline (PANI) is a promising candidate. Nanostructured polyaniline doped with organic dopant is electrodeposited and structurally characterized. Its transport properties are investigated for thermoelectric applications. The analysis of transmission electron microscopy image reveals that the sample is rod like nanostructure. This study shows that the type (inorganic/organic) of dopants plays an important role to influence the dimension of nanostructure and the electrical transport properties of PANI. In this study, organic dopant sulfosalicylic acid is proposed for enhancement of figure of merit through an increase in thermoelectric power and decrease in thermal conductivity. Compared to our earlier work the figure of merit evaluated is two orders higher than that of the inorganic dopant bismuth nitrate doped PANI. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39920. 相似文献
994.
Abhishek Pal Anirban Ganguly Avijit Ghosh Md Yousuf Bhowmira Rathore Dr. Rajkumar Banerjee Dr. Susanta Adhikari 《ChemMedChem》2014,9(4):727-732
We report a new family of bis‐arylidene oxindole derivatives that show highly selective estrogen receptor (ER)‐mediated anticancer activity at low‐nanomolar concentrations in ER‐positive (ER+) breast cancer cells. In terms of cell growth inhibition, IC50 values for these compounds in ER+ breast cancer cells are two to three orders of magnitude lower than in ER‐negative (ER?) breast cancer cells and non‐cancer cells. In comparison with known bis‐arylidene drugs, these compounds are at least three orders of magnitude more toxic than tamoxifen and 1.5–4‐fold more toxic than 4‐hydroxytamoxifen in ER+ MCF‐7 cancer cells. These oxindoles inhibit ER transactivation, and their anticancer activities are inhibited in ER‐depleted MCF‐7 cells. Some of these nonsteroidal molecules also exhibit essential properties of selective ER down‐regulation. From the development of two series of bis‐arylidene oxindole‐based compounds, we report a new series of anticancer agents for estrogen‐responsive breast cancer. 相似文献
995.
Sitipragyan Satapathy Vinay K. Singh Sai Sateesh Sagiri Tarun Agarwal Indranil Banerjee Mrinal K. Bhattacharya Naresh Kumar Kunal Pal 《应用聚合物科学杂志》2015,132(8)
This study was designed to examine the physicochemical and electrical properties of gelatin‐based hydrogels, emulgels, and bigels. The chemical studies suggested an increase in hydrogen bonding in the emulgel and bigel when sesame oil (SO; representative vegetable oil) and SO organogel (OG; representative OG) were incorporated within the gelatin matrix. The emulgel and bigel showed better mechanical properties and higher electrical impedances compared to the hydrogel. The hydrogel showed similar swelling at pH 1.2 and 7.2. The swelling of the emulgel and bigel was higher at pH 7.2. The formulations were found to be highly hemocompatible; this indicated their biocompatible nature. Ciprofloxacin, a model antimicrobial drug, was incorporated within the formulations. The release of the drug was found to be diffusion‐mediated. The antimicrobial efficiency of all of the drug‐loaded formulations was found to be equivalent. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41502. 相似文献
996.
A. Sen Y. Nazeer Ahammed B. C. Arya Tirthankar Banerjee G. Reshma Begam B. P. Baruah A. Chatterjee Anil K. Choudhuri Amit Dhir Trupti Das Pitamber Prasad Dhyani N. C. Deb Ranu Gadi Mangesh Gauns Sanjay Kumar Ghosh Abhishek Gupta K. C. Sharma A. H. Khan K. Maharaj Kumari Manish Kumar Arun Kumar Jagdish Chandra Kuniyal Anita Lakhani R. K. Meena P. S. Mahapatra S. W. A. Naqvi Dharam Pal Singh S. Pal Sipra Panda Rohtash J. Saikia P. Saikia A. Sharma Priyanka Sharma M. Saxena D. M. Shenoy C. Viswanatha Vachaspati S. K. Sharma T. K. Mandal 《Mapan》2014,29(4):273-284
In this paper, we present mass concentrations of particulate matter [PM2.5, PM10 size fractions and total suspended particulates (TSP)] measured simultaneously over land stations (Kullu, Patiala, Delhi, Ajmer, Agra, Lucknow, Varanasi, Giridih, Kolkata, Darjeeling, Jorhat, Itanagar, Imphal, Bhubaneswar, and Kadapa), mostly distributed across the Indo-Gangetic plain (IGP) of India as well as in the marine atmosphere over Bay of Bengal (BoB) in the period from 20 January to 3 February, 2014. The main objective of this study was to quantify the continental outflow of particulates (PM2.5, PM10 and TSP) from IGP and associated regions into the BoB along with low level north-east wind flow during winter monsoon period. The present study provides a glimpse of the aerosol loading over the IGP region. During this campaign, the highest average PM2.5 (187.8 ± 36.5 µg m?3, range 125.6–256.2 µg m?3), PM10 (272.6 ± 102.9 µg m?3, range 147.6–520.1 µg m?3) and TSP (325.0 ± 71.5 µg m?3, range 220.4–536.6 µg m?3) mass concentrations were recorded at Varanasi, Kolkata and Lucknow over middle and lower IGP regions. The PM2.5 (average 41.3 ± 11.9 µg m?3; range 15.0–54.4 µg m?3), PM10 (average 53.9 ± 18.9 µg m?3; range 30.1–82.1 µg m?3) and TSP (average 78.8 ± 29.7 µg m?3; range 49.1–184.5 µg m?3) loading over BoB were found to be comparable to land stations and suggests possible continental outflow. Over the continental region, the highest PM2.5/PM10 ratio was recorded at Delhi (0.87). The PM2.5/PM10 ratio over BoB (0.77) was found to be quite high and comparable to Varanasi (0.80) and Agra (0.79). 相似文献
997.
Shilpi Banerjee Partha Hajra Anindya Datta Asim Bhaumik Mykanth Reddy Mada Sri Bandyopadhyay Dipankar Chakravorty 《Bulletin of Materials Science》2014,37(3):497-504
Composites comprising of nanoparticles of Ni0?5Zn0?5Fe2O4 (NZF) and BaTiO3 (BT), respectively were synthesized by a chemical method. The particles had diameters in the range of 15–31 nm. NZF was prepared by a coprecipitation technique. This was soaked in a sol containing BT. Compositions synthesized were xNZF-(1 – x) BT, where x = 0?7, 0?5 and 0?3, respectively. The composites showed ferromagnetic hysteresis loops due to NZF phase. The analysis of coercivity variation as a function of temperature gave blocking temperatures in the range of 306–384 K depending on the diameter of the ferrite nanoparticles. This implied that superparamagnetic interactions are above these temperatures. The nanocomposites also exhibited ferroelectric behaviour arising due to the presence of BT. The remanent polarization of the samples was small. This was adduced to the nanosize of BT. The specimens showed magneto-dielectric (MD) effect in the magnetic field range 0–0?7 Tesla. The MD parameter measured at the maximum magnetic field was around 2%. This was one order of magnitude higher than that reported so far in similar composite systems. This was explained on the basis of a two-phase inhomogeneous medium model with an interface between them, the phases possessing drastically different electrical conductivities. 相似文献
998.
In robust design, uncertainty is commonly modelled with precise probability distributions. In reality, the distribution types and distribution parameters may not always be available owing to limited data. This research develops a robust design methodology to accommodate the mixture of both precise and imprecise random variables. By incorporating the Taguchi quality loss function and the minimax regret criterion, the methodology mitigates the effects of not only uncertain parameters but also uncertainties in the models of the uncertain parameters. Hydrokinetic turbine systems are a relatively new alternative energy technology, and both precise and imprecise random variables exist in the design of such systems. The developed methodology is applied to the robust design optimization of a hydrokinetic turbine system. The results demonstrate the effectiveness of the proposed methodology. 相似文献
999.
Takuji Kita Junya Murai Debasish Banerjee Akira Manabe Minjuan Zhang Yoichiro Kawai 《Journal of Electronic Materials》2014,43(6):1560-1566
We report wet chemical synthesis of a hierarchical nanocomposite thermoelectric material, (Bi,Sb)2Te3 + 2 vol.% Sb2O3, which exhibits a very high ZT value of 1.5 at 333 K. The key to such a high ZT value is to design the interfacial density (ID) of the nanodispersion and the mean diameter of the matrix (d) in the nanocomposite. To this end, (Bi,Sb)2Te3 with Sb2O3 nanodispersion was developed using in situ precipitation during solvothermal treatment. Nanocomposite structure was observed in sintered specimens. By evaluation of thermoelectric properties, it was confirmed that phonon scattering on the surface of Sb2O3 dispersion and κ ph correspondingly decreased with ID. The formation of a well-controlled Sb2O3 dispersion (mean diameter of dispersion: D = 1.5 nm, ID = 0.06 nm?1) and fine grains (d = 38 nm) led to an extremely low lattice thermal conductivity of 0.28 W m?1 K?1, while reducing the electrical conductivity moderately according to the conventional mixture rule. 相似文献
1000.
W.L. Dunn K. Banerjee A. Allen J. van Meter 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,263(1):179-182
A method to remotely identify vehicles or other targets that might be harboring conventional explosives is described. The method utilizes multiple responses from a target that is interrogated by gamma-ray and neutron pulses and employs a template-matching procedure that reduces the collected information into a figure-of-merit. The template-matching procedure seeks to identify suspect targets based on deviations between a response vector obtained from a target under scrutiny and templates from a library; the templates are characteristic of targets with known cargoes. The methodology is illustrated with simulated data and the results of preliminary experiments on simplified targets are presented. 相似文献