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1.
A Methodology for the Evaluation of a GPS Receiver Performance in Telematics Applications 总被引:1,自引:0,他引:1
Aloi D. N. Alsliety M. Akos D. M. 《IEEE transactions on instrumentation and measurement》2007,56(1):11-24
This paper presents a methodology to evaluate the position availability of automotive grade global positioning system (GPS) receivers intended for Telematics applications utilizing a multichannel GPS satellite signal simulator in a controlled laboratory environment. Initially, field testing of two distinct GPS receivers was conducted in an urban canyon environment and a foliage environment to assess each receiver's position availability performance. Test scenarios were then developed on a multichannel GPS satellite signal simulator in order to create controlled and repeatable stimuli to the GPS receivers. The scenarios take into account the actual satellite constellations at the same day, time, and locations of the field data collections. Furthermore, the number of visible satellites and power levels was adjusted in order to stimulate the hardware tracking sensitivity, hardware acquisition sensitivity, dynamic range, and navigation filter design, all of which impact position availability for GPS receivers. Quantitative results demonstrated good correlation between the results obtained using the developed test scenarios and the results from the field testing. The proposed methodology will result in reducing validation cost and time to market for automotive Telematics products 相似文献
2.
Végvári A Larsson AK Hjertén S Mannervik B 《Chembiochem : a European journal of chemical biology》2002,3(11):1117-1125
The tripeptide glutathione is a prominent intracellular constituent that provides protection against genotoxic and carcinogenic electrophiles and is also a component of several biological signal substances. Glutathione conjugates, free glutathione, and glutathione disulfide contain charged amino acid residues, which contribute to solubility in aqueous media. However, the amphipathic nature of glutathione conjugates and the small differences that may distinguish the S substituents, pose analytical problems in their resolution. The present study demonstrates how homologous S-alkyl and S-benzyl conjugates of high structural similarity can be efficiently resolved by capillary electrophoresis. Inclusion of beta-cyclodextrins in the buffer or in a polyacrylamide gel affords baseline separation of the analytes. The separation methods described are applicable to enzyme assays in vitro and to the identification and quantification of glutathione conjugates of importance in toxicology and physiology. The contribution of beta-cyclodextrin to the separation is primarily based on interactions between its hydrophobic cavity and the S-alkyl and S-benzyl groups of the analytes. 相似文献
3.
Mórocz IA Janoos F van Gelderen P Manor D Karni A Breznitz Z von Aster M Kushnir T Shalev R 《International journal of imaging systems and technology》2012,22(1):81-96
The aim of this article is to report on the importance and challenges of a time-resolved and spatio-temporal analysis of fMRI data from complex cognitive processes and associated disorders using a study on developmental dyscalculia (DD). Participants underwent fMRI while judging the incorrectness of multiplication results, and the data were analyzed using a sequence of methods, each of which progressively provided more a detailed picture of the spatio-temporal aspect of this disease. Healthy subjects and subjects with DD performed alike behaviorally though they exhibited parietal disparities using traditional voxel-based group analyses. Further and more detailed differences, however, surfaced with a time-resolved examination of the neural responses during the experiment. While performing inter-group comparisons, a third group of subjects with dyslexia (DL) but with no arithmetic difficulties was included to test the specificity of the analysis and strengthen the statistical base with overall fifty-eight subjects. Surprisingly, the analysis showed a functional dissimilarity during an initial reading phase for the group of dyslexic but otherwise normal subjects, with respect to controls, even though only numerical digits and no alphabetic characters were presented. Thus our results suggest that time-resolved multi-variate analysis of complex experimental paradigms has the ability to yield powerful new clinical insights about abnormal brain function. Similarly, a detailed compilation of aberrations in the functional cascade may have much greater potential to delineate the core processing problems in mental disorders. 相似文献
4.
The hydrogen economy is seeking its killer application, which can break down the ‘chicken and egg problem’, i.e., no hydrogen powered car can be sold if it cannot be refueled, and nobody will invest to a hydrogen refueling station if no one has a hydrogen powered vehicle. The applications like material handling, backup-power, and small stationary combined heat and power (CHP) engines are the most promising candidates, which may show financial return in 3–5 years. The replacement of fossil fuel with hydrogen in the automotive industry offers a substantial reduction of the harmful environmental effects, however, it is still the most challenging because of the absence of the hydrogen infrastructure, the price and the lifetime of the fuel cell (FC) engine and the unsuitable regulations, as well. In this work a new possible market was identified and analyzed in different points of view. This market segment is a car-sharing system operating with small urban vehicles, which not only can solve some environmental problems (e.g., air pollution and CO2 emission), but also helps to reduce congestion, secure energy supply and ease its distribution. First, a sensitivity analysis was done and the key performance indicators of the system were determined. The financial return of a hydrogen-based car-sharing system was examined carefully as a function of the rated power of the fuel cell power train, the way of hydrogen supply, the cost of the hydrogen and the size of the car fleet. Finally, a possible hydrogen-based car-sharing service was designed and optimized to the downtown of Budapest, Hungary. A sustainable system was proposed, which can satisfy the needs of the business (i.e., profitability) and the environment. 相似文献
5.
Akos Szederjei 《Zeitschrift für Jagdwissenschaft》1958,4(2):69-83
Zusammenfassung Beobachtungen von 17 Rebhuhnvölkern in drei Jahren zeigten, daß sie sich häufig in baum-und strauchbewachsenen Flächen aufhielten. Weitere Aufenthaltsorte waren in abnehmender Häufigkeit Mais, Roggen, Gras und Unkraut, Rüben, Weizen, Kartoffeln, Luzerne.Bei der Wahl des Nistplatzes werden ebenfalls kleine Flächen, die mit Sträuchern und Bäumen bewachsen sind, vorgezogen. An zweiter Stelle lag die Brutstätte in Gras und Unkraut oder in Luzerne. Am geringsten war die Zahl der Nester im Getreide. In der gleichen Reihenfolge fiel die Nestdichte je Flächeneinheit, die Eizahl je Gelege und die Zahl der überlebenden Jungen.Für die Anlage verschiedener Typen von Remisen werden genaue Anweisungen gegeben.Die Remisen sollen einen bevorzugten Aufenthaltsort darstellen, hierzu sollen sie Störungsfreiheit und Schutz gegen Witterungsunbilden und Raubwild bieten und dadurch eine Saugwirkung ausüben. Im Winter kann die Saugwirkung durch Fütterung und durch sternförmige Furchen, die mit dem Schneepflug gezogen sind, erhöht werden. Die Saugwirkung hängt von der Struktur und dem Flächenumfang der Remise ab, sie beträgt bei Rebhühnern bis zu 1000 m und bei Fasanen bis zu 2000 m.Die Saugwirkung der Remise ist im Frühjahr ungefähr halb so groß wie im Winter.
Summary Observations of 17 covies of partridges during 3 years showed that they stayed frequently in areas grown with trees and bushes. Further haunts were in diminishing frequency maize, rye, grass and weeds, turnips, wheat, potatoes, and lucern.In the choice of breeding places they prefer, too, small areas grown with bushes and trees. In the second line breeding places were found in grass and weeds or lucern. The smallest number of nests was found in corn. In the same sequence were diminished the density of nests per unit of areal, the number of eggs laid, and the number of surviving chicken.For the creation of different types of shelters exact instructions are given.Shelters ought to represent a preference haunt, therefore they must offer lack of disturbances, protection against rough weather and rapacious animals so that thay may exercise a certain suctorial effect. In winter this suctorial effect may be increased by feeding and by star formed furrows made by the snowplough. The suctorial effect depends of the structure and the areal of the shelter, in case of partridges it amounts up to 1000 m and with pheasants up to 2000 m.The suctorial effect of the shelter is about half as big in spring than in winter.
Résumé Les observations faites au cours de trois ans sur 17 peuples de perdrix ont démontré que ceux-ci stationnent très souvent sur plaines couvertes des arbres et buissons. D'autres lieux de séjour étaient suivant leur fréquence diminuente: mais, seigle, herbe et ivraie, ravières, froment, pommes de terre et luzerne.Le perdrix préfère également pour la nidification petites plaines couvertes de buissons et d'arbres. En deuxième lieu vient pour la nidification l'herbe et l'ivraie ou la luzerne. Peu considérable était le nombre des nids se trouvant parmi le blé. Le même ordre est établi en ce qui concerne la densité des nids par unité de superfice; le nombre des oeufs par nichée et le nombre des perdreaux qui survivent.Pour la construction de diverses types de remises on vient de donner des instructions précises.Les remises devant présenter un lieu de séjour préféré, il faut que ceux-ci soient à l'abri de tout dérangement et qu'ils offrent un réfuge contre les intempéries et les bêtes nuisibles au gibier et qu'en cela même ils auront un effet aspirant.Cet effet aspirant sera augmenté pendant l'hiver en donnant à manger et en tirant à l'aide d'une charrue à neige des sillons en forme d'étoile. Il dépend aussi de la structure et de l'étendue de la remise qui doit avoir 1000 mètres pour le perdrix, et 2000 mètres pour le faisan.Au printemps, l'effet aspirant de la remise ne sera pas qu'environ de la moitié si grand qu'en hiver.相似文献
6.
Wiesel O Tóth IE Boldogkoi Z Hornyák A Bokor V Halász B Gerendai I 《Microscopy research and technique》2004,63(4):244-252
Using the transneuronal viral tracing method, the central nervous system (CNS) connections of the uterine horn were studied in virgin, pregnant, and in lactating rats. The frequency of viral labeling in the brain and the distribution of virus-infected neurons from the uterine horn were compared among groups. There was a marked difference in the frequency of viral labeling in the brain stem. In virgin rats more than half of the brain stems (5 out of 9) were labeled. In contrast, in pregnant animals viral-labeled neurons were detected in only a few cases (3 out of 16) and almost each brain stem of the lactating group was labeled (12 out of 13). A similar, less marked difference was observed in the hypothalamus. The pattern of distribution of infected neurons was similar in each group. In the brain stem, the nucleus of the solitary tract, dorsal motor nucleus of the vagus, area postrema, gigantocellular and paragigantocellular nucleus, ventrolateral medulla, A5 cell group, and caudal raphe nuclei were the most frequently labeled structures. In the diencephalon, viral-infected neurons were detected primarily in the hypothalamic paraventricular nucleus. The telencephalon was devoid of infected cells. Data suggest that the CNS control of the uterine horn varies depending on reproductive status. The low frequency of brain labeling in pregnant rats may be related to the almost complete lack of sympathetic fibers in the uterus prior to parturition and the very high frequency of labeling in lactating animals to the postpartum hyperinnervation of the uterus. 相似文献
7.
Cornel BrisanAuthor Vitae Akos Csiszar Author Vitae 《Mechanism and Machine Theory》2011,46(11):1647-1668
A reconfigurable robotic system permits multiple configurations having different characteristics, using mostly modularized building blocks. The goal of this paper is to investigate how the shape, dimensions and the distribution of singularities in the workspace for different configurations, with different degrees of freedom, of a reconfigurable robotic system, are changed. The computation of the workspace is based on the modularity property of the system. The presented results are also experimentally validated. 相似文献
8.
Reham Atallah Juergen Gindlhuber Wolfgang Platzer Thomas Brnthaler Eva Tatzl Wolfgang Toller Jasmin Strutz Sonja Rittchen Petra Luschnig Ruth Birner-Gruenberger Christian Wadsack Akos Heinemann 《International journal of molecular sciences》2021,22(21)
Placental hypervascularization has been reported in pregnancy-related pathologies such as gestational diabetes mellitus (GDM). Nevertheless, the underlying causes behind this abnormality are not well understood. In this study, we addressed the expression of SUCNR1 (cognate succinate receptor) in human placental endothelial cells and hypothesized that the succinate–SUCNR1 axis might play a role in the placental hypervascularization reported in GDM. We measured significantly higher succinate levels in placental tissue lysates from women with GDM relative to matched controls. In parallel, SUCNR1 protein expression was upregulated in GDM tissue lysates as well as in isolated diabetic fetoplacental arterial endothelial cells (FpECAds). A positive correlation of SUCNR1 and vascular endothelial growth factor (VEGF) protein levels in tissue lysates indicated a potential link between the succinate–SUCNR1 axis and placental angiogenesis. In our in vitro experiments, succinate prompted hallmarks of angiogenesis in human umbilical vein endothelial cells (HUVECs) such as proliferation, migration and spheroid sprouting. These results were further validated in fetoplacental arterial endothelial cells (FpECAs), where succinate induced endothelial tube formation. VEGF gene expression was increased in response to succinate in both HUVECs and FpECAs. Yet, knockdown of SUCNR1 in HUVECs led to suppression of VEGF gene expression and abrogated the migratory ability and wound healing in response to succinate. In conclusion, our data underline SUCNR1 as a promising metabolic target in human placenta and as a potential driver of enhanced placental angiogenesis in GDM. 相似文献
9.
Wu MC Tóth G Sápi A Leino AR Kónya Z Kukovecz A Su WF Kordás K 《Journal of nanoscience and nanotechnology》2012,12(2):1421-1424
Titanium dioxide nanofibers were synthesized and applied in flexible composite films that are easy to handle and recycle after use. The nanofibers were obtained in a multi-step procedure. First, sodium titanate nanofibers were prepared from TiO2 nanoparticles through the alkali hydrothermal method. In the next step, sodium hydrogen titanate nanofibers were made by washing the sodium titanate nanofibers in HCl solution. Finally, the sodium hydrogen titanate nanofibers were transformed to TiO2 anatase nanofibers by calcination in air. The photocatalytic activity of TiO2 anatase nanofibers were evaluated and compared to a TiO2 nanoparticle catalyst by decomposing methyl orange dye in aqueous solutions. The achieved reaction rate constant of TiO2 anatase nanofibers was comparable to that of Degussa P25. Paper-like flexible composite films were prepared by co-filtrating aqueous dispersions of TiO2 catalyst materials and cellulose. The composite films made from the nanofibers exhibit better mechanical integrity than those of the nanoparticle-cellulose composites. 相似文献
10.
Emission problems associated with the use of fossil fuels have led to numerous research projects on the use of renewable fuels. The aim of this study is to evaluate the effects of blends containing croton mogalocarpus oil (CRO)-Butanol (BU) alcohol-diesel (D2) on engine performance, combustion, and emission characteristics. Samples investigated were 15%CRO-5%BU-80%D2, 10%CRO-10%BU-80%D2, and diesel fuel (D2) as a baseline. The density, viscosity, cetane number CN, and contents of carbon, hydrogen, and oxygen were measured according to ASTM standards. A four cylinder turbocharged direct injection (TDI) diesel engine was used for the tests. It was observed that brake specific energy consumption (BSEC) of blends was found to be high when compared with that of D2 fuel. Butanol containing blends show peak cylinder pressure and heat release rate comparable to that of D2 on higher engine loads. Carbon dioxide (CO2) and smoke emissions of the BU blends were lower in comparison to D2 fuel. 相似文献