2,068 research outputs found
Report of MAGSAT project by Survey of India
Magsat data fo quiet days for the period 4.11.79, 17.11.79 to 24.11.79, which pertains to 44 passes, was screened to exclude the the period of exclude the period of maximum diurnal variation. The results of this screening process is a data set that has the effect, (or at least the major part of the effect), of the external field removed from it. Such a data set is the basis for further analysis which is in hand. The data set is now being reduced to horizontal plane. The mathematical techniques uses a finite harmonic series representation of the three dimensional data, combined with least squares approach for the solution of coefficients. A computer programme was developed to reduce satellite data to a common elevation
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Blimp-1-dependent and -independent natural antibody production by B-1 and B-1-derived plasma cells.
Natural antibodies contribute to tissue homeostasis and protect against infections. They are secreted constitutively without external antigenic stimulation. The differentiation state and regulatory pathways that enable continuous natural antibody production by B-1 cells, the main cellular source in mice, remain incompletely understood. Here we demonstrate that natural IgM-secreting B-1 cells in the spleen and bone marrow are heterogeneous, consisting of (a) terminally differentiated B-1-derived plasma cells expressing the transcriptional regulator of differentiation, Blimp-1, (b) Blimp-1+, and (c) Blimp-1neg phenotypic B-1 cells. Blimp-1neg IgM-secreting B-1 cells are not simply intermediates of cellular differentiation. Instead, they secrete similar amounts of IgM in wild-type and Blimp-1-deficient (PRDM-1ΔEx1A) mice. Blimp-1neg B-1 cells are also a major source of IgG3. Consequently, deletion of Blimp-1 changes neither serum IgG3 levels nor the amount of IgG3 secreted per cell. Thus, the pool of natural antibody-secreting B-1 cells is heterogeneous and contains a distinct subset of cells that do not use Blimp-1 for initiation or maximal antibody secretion
MOVIEMOD: Een beslisingsondersteunend systeem voor de introductie van nieuwe films
Het produceren en distribueren van nieuwe films is risicovol. Distibuteurs en bioscoopexploitanten
hebben daarom baat bij informatie over het succes van een film, voordat de film in de bioscoop
draait. In dit artikel wordt een model gepresenteerd, genaamd MOVIEMOD, dat in staat is
zulke voorspellingen te leveren door een voorvertoning van de film aan een steekproef van
potentiële bezoekers. Daarnaast kan het model ook helpen bij het opstellen van het mediaplan,
omdat het in staat is het effect van aanpassingen in het mediaplan te bepalen. Het model is twee
keer toegepast in de praktijk: de eerste keer in de Verenigde Staten, en daarna in Nederland.
Omdat in Nederland de distributeur en de belangrijkste bioscoopexploitant van de film deelnamen,
waren we in staat om het gebruik van MOVIEMOD als decision support instrument te
onderzoeken. De voorspelling van MOVIEMOD bij het gebruikte media- en distributieplan was
redelijk nauwkeurig (een afwijking van 4% met het werkelijke bezoekersaantal) en deze voorspelling
was beter dan die van een aantal benchmark modellen. De resultaten tonen aan dat
MOVIEMOD een waardevol marketing instrument kan zijn voor de filmindustrie
Analysis of acoustic emission data for bearings subject to unbalance
Acoustic Emission (AE) is an effective nondestructive method for investigating the behavior of materials under stress. In recent decades, AE applications in structural health monitoring have been extended to other areas such as rotating machineries and cutting tools. This research investigates the application of acoustic emission data for unbalance analysis and detection in rotary systems. The AE parameter of interest in this study is a discrete variable that covers the significance of count, duration and amplitude of AE signals. A statistical model based on Zero-Inflated Poisson (ZIP) regression is proposed to handle over-dispersion and excess zeros of the counting data. The ZIP model indicates that faulty bearings can generate more transient wave in the AE waveform. Control charts can easily detect the faulty bearing using the parameters of the ZIP model. Categorical data analysis based on generalized linear models (GLM) is also presented. The results demonstrate the significance of the couple unbalance
Camera distortion self-calibration using the plumb-line constraint and minimal Hough entropy
In this paper we present a simple and robust method for self-correction of
camera distortion using single images of scenes which contain straight lines.
Since the most common distortion can be modelled as radial distortion, we
illustrate the method using the Harris radial distortion model, but the method
is applicable to any distortion model. The method is based on transforming the
edgels of the distorted image to a 1-D angular Hough space, and optimizing the
distortion correction parameters which minimize the entropy of the
corresponding normalized histogram. Properly corrected imagery will have fewer
curved lines, and therefore less spread in Hough space. Since the method does
not rely on any image structure beyond the existence of edgels sharing some
common orientations and does not use edge fitting, it is applicable to a wide
variety of image types. For instance, it can be applied equally well to images
of texture with weak but dominant orientations, or images with strong vanishing
points. Finally, the method is performed on both synthetic and real data
revealing that it is particularly robust to noise.Comment: 9 pages, 5 figures Corrected errors in equation 1
Investigation on Additive Manufacturing as an enabler for reshoring manufacturing activities
The recent phenomenon known as re-shoring, has gained momentum among developed countries. It is also evident that the new generation of technologies such as Additive Manufacturing (AM) and intelligent robotics can affect the manufacturing location decision. This study aims to investigate how AM can help companies to re-shore manufacturing activities. Three in-depth case studies are conducted where AM is used as primary manufacturing approach to reduce the number of suppliers and shorten the supply chain. The results show that companies can reduce transportation, lead-time, inventory and substantially improve customisation, meanwhile accommodate product changes as well as process changes in production
Studies on the Antioxidant Properties of Various extracts of Hippophae rhamnoide
Sea Buckthorn (Hippophae rhamnoides) a spiny shrub native to Ladakh Region of Jammu and Kashmir, have been found to posses so many medicinal properties from times immoral. From this point of view the antioxidant property of the plant fruit extracts have been analysed by DPPH method. Various plant extracts viz, fruit, leaf and root have been analysed for the antioxidant power determination in which fruit extracts showed highest free radical scavenging activity followed by leaf and root extracts. Among the solvents which have been used, more polar solvents showed highest antioxidant activity than the less polar solvent extracts. The IC50 value of various plant extracts as determined have been found to be 40 for DCM extract of fruit, 38 for Methanolic extract of fruit and 30 for the water extract of fruit. Similarly the leaf extracts posses IC50 value as 51, 47 and 37 respectively for DCM, Methanol and Water extracts. The IC50 values of various root extracts have been found to be 53, 50 and 48 respectively for DCM, Methanol and Water
Proteomic analysis of tomato (Lycopersicon esculentum) pollen
In flowering plants, pollen grains are produced in the anther and released to the external environment with the primary function of delivering sperm cells to the female gametophyte. This study was conducted to identify proteins in tomato pollen and to analyse their roles in relation to pollen function. Tomato is an important crop which is grown worldwide and is an excellent experimental system. Proteins were extracted from pollen, separated by two-dimensional gel electrophoresis (2-DE), and identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) and peptide mass fingerprinting. Of the 960 spots observed on Colloidal Coomassie Blue (CCB)-stained 2-DE gels, 190 were selected for analysis. Of these, 158 spots, representing 133 distinct proteins, were identified by searching the NCBInr and Expressed Sequence Tag databases. The identified proteins were classified based on designated functions and the majority included those involved in defence mechanisms, energy conversions, protein synthesis and processing, cytoskeleton formation, Ca(2+) signalling, and as allergens. A number of proteins in tomato pollen were similar to those reported in the pollen of other species; however, several additional proteins with roles in defence mechanisms, metabolic processes, and hormone signalling were identified. The potential roles of the identified proteins in the survival strategy of the small, independent, two-celled pollen grain of tomato, and subsequently in pollen germination and tube growth are discussed
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