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21.
For operators of Internet shops and their investors on the one hand, and suppliers on the other hand, knowledge of the consumer market is becoming critical in terms of the risk of non-payment for purchased goods, as most small e-shops maintain their stocks according to current demand. The aim of this paper is to identify customers who come from different districts of Slovakia and display a certain type of consumer behavior regarding the risk connected with willingness to pay for goods purchased via the Internet. To solve this problem we used data from a specialized e-retailer and Geographic Information Systems (GIS) as a Decision Support System generator for constructing maps of consumers to investigate the operation of an e-shop. In the article, we used data from the years 2012–2015 concerning 489 buyers, including their addresses and other geographical data about the consumers and their purchases, and integrated them into the GIS environment. Subsequently, the data were analyzed and documented by means of GIS and maps of consumers were generated. The result of this study is to show that GIS can play a significant role in the decision-making process of e-shops in support of a manager’s experience. The geographical results were evaluated statistically in order to offer a better information capability. 相似文献
22.
Milan Vlček Ladislav Tichý Jiří Klikorka Ales Tříska 《Journal of Materials Science》1989,24(7):2508-2512
The optical properties of Ge40-x
Sb
x
Se60 glasses have been studied in the infrared spectral region and also in the short wavelength region. The spectral dependence of the absorption coefficient in the region of multiphonon absorption, optical gap and average gap was discussed in relation to the chemical composition. It is supposed that the structure of these glasses is complicated due to structural units containing mainly Ge-Se, Sb-Se and also Ge-Ge, Ge-Sb and Sb-Sb bonds. 相似文献
23.
Cluster analysis is a tool often employed in the micro-array techniques but used less in the real-time PCR. Herein we present core SAS code that instead of the Euclidian distances takes correlation coefficient as a dissimilarity measure. The dissimilarity measure is made robust using a rank-order correlation coefficient rather than a parametric one. There is no need for an overall probability adjustment like in scoring methods based on repeated pair-wise comparisons. The rank-order correlation matrix gives a good base for the clustering procedure of gene expression data obtained by real-time RT-PCR as it disregards the different expression levels. Associated with each cluster is a linear combination of the variables in the cluster, which is the first principal component. Large set of variables can then be replaced by the set of cluster components with little loss of information. In this way, distinct clusters containing unregulated housekeeping genes along with other steadily expressed genes can be disclosed and utilized for standardization purposes. Simulated data in parallel with the data from a biological experiment were taken to validate the SAS macro. For both cases, good intuitive results were obtained. 相似文献
24.
Hernychova L Toman R Ciampor F Hubalek M Vackova J Macela A Skultety L 《Analytical chemistry》2008,80(18):7097-7104
Rapid and reliable detection, identification, and typing of bacterial species are necessary in response to natural or terrorist-caused outbreaks of infectious diseases and play crucial roles in diagnosis and efficient treatment. We report here two proteomic approaches with a high potential in the detection and identification of Coxiella burnetii, the causative agent of Q fever. The first of them starts with the acetonitrile (ACN) and trichloroacetic acid extractions of inactivated C. burnetii cells followed by the detection of extracted molecules and ions derived from the inactivated cells by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. In the second approach, identification of the proteins extracted by ACN is accomplished after enzymatic digestion by electrospray tandem mass spectrometry coupled to a nanoscale ultraperformance liquid chromatography (LC-MS/MS). In order to observe morphological differences on the surface structures upon extraction, the inactivated and treated cells of the bacterium were examined by electron microscopy. The LC-MS/MS approach has allowed identification of 20 proteins in the ACN extracts of C. burnetii strain RSA 493 that were observed in more than 3 out of 10 experiments. 相似文献
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The health risk and dose calculations from exposure to indoor radon and its decay products are generally based on long-term integral measurements and standard ICRP recommendations. In this context, the results of assessments predicate more about human activities inside the building instead of a quality and an effectiveness of applied measures against the radon. The present paper is focused on a set of different measuring techniques and methods practically used for a classification of buildings regarding to the radon protection requirements. The fundamental quantitative and qualitative procedures of radon transport pathways and radon sources analysis, commonly named as radon diagnostic methods are performed in detail. 相似文献
27.
Christiane Maierhofer Mathias Röllig Michael Gower Maria Lodeiro Graham Baker Christian Monte Albert Adibekyan Berndt Gutschwager Lenka Knazowicka Ales Blahut 《International Journal of Thermophysics》2018,39(5):61
For assuring the safety and reliability of components and constructions in energy applications made of fiber-reinforced polymers (e.g., blades of wind turbines and tidal power plants, engine chassis, flexible oil and gas pipelines) innovative non-destructive testing methods are required. Within the European project VITCEA complementary methods (shearography, microwave, ultrasonics and thermography) have been further developed and validated. Together with partners from the industry, test specimens have been constructed and selected on-site containing different artificial and natural defect artefacts. As base materials, carbon and glass fibers in different orientations and layering embedded in different matrix materials (epoxy, polyamide) have been considered. In this contribution, the validation of flash and lock-in thermography to these testing problems is presented. Data analysis is based on thermal contrasts and phase evaluation techniques. Experimental data are compared to analytical and numerical models. Among others, the influence of two different types of artificial defects (flat bottom holes and delaminations) with varying diameters and depths and of two different materials (CFRP and GFRP) with unidirectional and quasi-isotropic fiber alignment is discussed. 相似文献
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Patrick Guertler Christina Brandl Heinrich H. D. Meyer Ales Tichopad 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2012,7(3):195-202
Public concern has been expressed on the use of genetically modified (gm) maize MON810 as animal feed and for human consumption. Several studies have been conducted on potential effects of feeding MON810 to livestock focusing on animal performance, animal health and fate of recombinant DNA or protein. Though, no information on effects of feeding gm maize on the gene expression level is available so far. From 2005 until 2007, a study with 36 lactating dairy cows fed gm maize (N?=?18, MON810) or the near-isogenic counterpart (N?=?18) was carried out, investigating the fate of recombinant DNA and protein. After a period of 25?months, ten cows fed transgenic maize and seven cows fed near-isogenic maize were slaughtered due to operational reasons. In a short follow-up study, tissues of the gastrointestinal tract and samples from liver were used for gene expression analysis of major genes of the inflammation, cell cycle and apoptosis pathways. Statistical analysis of the examined gene expression pattern revealed no significant difference in the gene expression profile of cows fed transgenic or near-isogenic feed ration. Therefore, it can be assumed that compared to near-isogenic feed, gm maize MON810 does not have any effect on major genes involved in apoptosis, inflammation and cell cycle in the gastrointestinal tract and in the liver of dairy cows. 相似文献