Search results for "POINT"
showing 10 items of 4385 documents
The Transfer Function of Non-Stationary Indoor Channels and its Relationship to System Functions of LFMCW Radars
2021
This paper studies the relationship between the time-variant (TV) channel transfer function (CTF) of non-stationary indoor channels and the system functions of linear frequency modulated continuous waves (LFMCW) radars. To do so, we consider a moving person/object in indoor environments, which is modelled by a cluster of moving point scatterers. It is shown that the TVCTF can be obtained from the beat signal of LFMCW radar systems. Analytical expressions are derived for the TV demodulated radar response, the complex channel gain, and the TV Doppler-delay profile. A relationship between the presented results and existing non-stationary indoor channel models assuming pulsed wave systems is al…
I CARCINOMI TRIPLO-NEGATIVI DELLA MAMMELLA: caratterizzazione morfologica e immunoistochimica della stromatogenesi tumorale, del contesto immunologic…
2021
“Facts Are Grasped by Us in Pictures (PT, 2.1). Remarks on Pictures and Facts in Wittgenstein’s Tractatus
2023
This paper proposes a (re)reading of the famous section in the Tractatus Logico-philosophicus, 2.1: “We picture facts to ourselves” and its relation to the similar section in the Prototractatus, 2.1: “Facts are grasped by us in images”. We reject the dominant solution that interprets the relation between facts and images as an isomorphic relation and propose that instead it is an internal relation: there are no facts that are not perceived through images. In other words: For us, linguistic animals, there is no world independent of language.
On the timing properties of SAX J1808.4-3658 during its 2015 outburst
2017
We present a timing analysis of the 2015 outburst of the accreting millisecond X-ray pulsar SAX J1808.4-3658, using non-simultaneous XMM-Newton and NuStar observations. We estimate the pulsar spin frequency and update the system orbital solution. Combining the average spin frequency from the previous observed, we confirm the long-term spin down at an average rate $\dot{\nu}_{\text{SD}}=1.5(2)\times 10^{-15}$ Hz s$^{-1}$. We also discuss possible corrections to the spin down rate accounting for mass accretion onto the compact object when the system is X-ray active. Finally, combining the updated ephemerides with those of the previous outbursts, we find a long-term orbital evolution compatibl…
Über die verzweigung von polydodecylmethacrylat
1970
Zur Untersuchung der Losungseigenschaften und des Ausmases der Verzweigung von radikalisch gewonnenem Polydodecylmethacrylat wurden Fraktionen von niedrig- und hochumgesetzten Praparaten im Molekulargewichtsbereich von 1,5·105 bis 8·106 auf ihr Molekulargewicht und ihre Knaueldimension hin vermessen. Die Methoden der Lichtstreuung, der Viskosimetrie, der Sedimentation in der Ultrazentrifuge, der Osmometrie und der Gelchromatographie wurden benutzt. Fur die Streulichtmessungen diente ein Eigenbaulichtstreuungsgerat, das wegen seines grosen Winkelmesbereiches eine recht genaue Festlegung der Anfangssteigung der Streukurve und damit des Tragheitsradius ermoglicht. Das Quadrat des Tragheitsradi…
Evaluation of Microbiological and Physico-Chemical Quality of Raw Milk from Sibiu Dairy Farm Province of Romania
2011
Research aims at benchmarking the quality of raw milk supplied by four private farms in the county of Sibiu at a distance of about 25 km each for a period of three months (April, May, June 2010). Samples were subject to particularly microbiological measurements (total number of germ and somatic cells), physico-chemical (acidity, fat density, non-fat dry matter, protein and freezing point titre) by international standard methods. The results of the four farms show different variations of the parameters analyzed as follows: 55.5% of the samples fall in physico-chemical parameters of standard quality and 79% of the samples fall within the parameters of microbiological quality standard and with…
Comparative analysis of the electrostatics of the binding of cationic proteins to vesicles: Asymmetric location of anionic phospholipids
2009
The role of electrostatics is studied in the adsorption of cationic proteins to zwitterionic phosphatidylcholine (PC) and anionic PC/phosphatidylglycerol (PG) mixed small unilamellarvesicles (SUVs). For model proteins the interaction is monitored vs. PG content at low ionic strength. The adsorption of lysozyme and myoglobin (isoelectric point, pl 7-11) is investigated in SUVs, along with changes of the fluorescence emission spectra of the cationic proteins, via their adsorption on SUVs. In the Gouy-Chapman formalism, the activity coefficient goes with the square of charge number. Deviations from the ideal model could indicate the asymmetric location of the anionic phospholipid in the bilaye…
An environment based approach for the ant colony convergence
2020
Abstract Ant colony optimization (ACO) algorithms are a bio inspired solutions which have been very successful in combinatorial problem solving, also known as NP-hard problems, including transportation system optimization. As opposed to exact methods, which could give the best results of a tested problem, this meta-heuristics is based on the stochastic logic but not on theoretical mathematics demonstration (or only on certain well defined applications). According to this, the weak point of this meta-heuristics is his convergence, its termination condition. We can finds many different termination criteria in the scientific literature, yet most of them are costly in resources and unsuitable f…
The cryogenic anticoincidence detector for ATHENA-XMS: preliminary results from the new prototype
2012
ATHENA has been the re-scoped IXO mission, and one of the foreseen focal plane instrument was the X-ray Microcalorimeter Spectrometer (XMS) working in the energy range 0.3-10 keV, which was a kilo-pixel array based on TES (Transition Edge Sensor) detectors. The need of an anticoincidence (AC) detector is legitimated by the results performed with GEANT4 simulations about the impact of the non x-ray background onto XMS at L2 orbit (REQ. < 0.02 cts/cm2/s/keV). Our consortium has both developed and tested several samples, with increasing area, in order to match the large area of the XMS (64 mm2). Here we show the preliminary results from the last prototype. The results achieved in this work off…
Studies on antimony trifluoride in thiocyanate salt matrices. Evidence for the formation of fluoro-thiocyanato anti-mony(III) species
1990
Abstract Antimony trifluoride can be dissolved in fused KNCS or NH4NCS giving yellow-orange solutions which are stable only for a short time just above their melting point. Infrared an Mossbauer results on solidified samples reveal the formation of mixed fluoro-thiocyanato antimony(III) species and indicate a different behaviour in the two matrices.