Showing papers by "University of Patras published in 1984"
TL;DR: In this paper, single-channel seismic reflection profiling data are presented from the Gulf of Corinth and from the continental margin outside the gulf of Patras, where different tectonic styles are exhibited in the two regions.
170 citations
TL;DR: In this article, a macroscopic modelling and analysis of multilane homodirectional freeway flow is discussed, where two existing models are extended and treated numerically so that their simplifying assumptions are relaxed.
Abstract: The subject of macroscopic modelling and analysis of multilane homodirectional freeway flow is discussed in this paper. Two existing models are extended and treated numerically so that their simplifying assumptions are relaxed. Further, two new formulations are developed; the first is two dimensional with respect to space (i.e. in addition to the street length it includes the street width explicitly) while the second is one dimensional high order dynamic (i.e. it incorporates a momentum equation in order to take into acount acceleration and inertia effects). All modelling alternatives are implemented into a few exemplary situations representing uninterrupted and interrupted flow conditions. Finally, comparisons with aggregate results obtained from microscopic simulation are presented.
123 citations
TL;DR: It is strongly recommended that in patients with compromised adrenal function, treatment with rifampicin must be accompanied by doubling or tripling the dose of adrenal steroids to maintain adequate steroid replacement therapy.
Abstract: Rifampicin induced profound alterations in cortisol metabolism when administered to three patients with primary adrenal failure receiving adequate corticosteroid replacement therapy. In one patient, adrenal crisis was precipitated after the institution of rifampicin therapy for treatment of coexistent tuberculosis and in another, profound asthenia, decrease in blood pressure, hyperkalemia, and hyponatremia developed during the hydrocortisol kinetic study. The clinical symptoms subsided and the electrolyte abnormalities were corrected approximately 7 days after rifampicin withdrawal. The half-life of hydrocortisol and the area under the curve were decreased by 35% and 23%, respectively, whereas the systemic clearance was increased by 35% during rifampicin administration. It appears, that the effectiveness of glucocorticoids and mineralocorticoids were greatly impaired by rifampicin administration due to induction of liver steroid-metabolizing enzymes. It is strongly recommended that in patients with compromised adrenal function, treatment with rifampicin must be accompanied by doubling or tripling the dose of adrenal steroids to maintain adequate steroid replacement therapy.
98 citations
TL;DR: In this paper, three numerical techniques for macroscopic analysis of traffic dynamics at signalized links (isolated or coordinated) are presented, based on finite differences in time and space.
Abstract: Three numerical techniques for macroscopic analysis of traffic dynamics at signalized links (isolated or coordinated) are presented. The techniques are based on finite differences in time and space and assist in implementing continuum models at real situations. The general methodology presented allows treatment of any arrival and departure pattern, inclusion of sinks or sources, employment of any desired equilibrium flow-density relationship and arbitrary specified initial conditions. Implementation of the proposed method to a signalized intersection and a coordinated link suggests satisfactory agreement with field data and notable agreement with analytical results, respectively. Comparisons made under progressively realistic assumptions demonstrate substantial improvements in model performance as the complexity of the assumptions increases
79 citations
TL;DR: In this paper, an energy-band model for pyrrhotite was presented based on the energy levels calculated for an octahedral FeS10−6 cluster, the X-ray spectroscopical data, the magnetic, electrical and optical properties of this compound and the energyband calculations for NiS.
44 citations
TL;DR: In this article, the negative binomial distribution of order k was introduced and briefly studied, and it was shown that it is a proper probability distribution, and its probability generating function, mean and variance were derived.
Abstract: The negative binomial distribution of order k is introduced and briefly studied. First it is shown that it is a proper probability distribution. Then its probability generating function, mean and variance are derived. Finally it is shown that the number of trials until the rth kth consecutive success (r ≧ 1, k ≧ 1) in independent trials with constant success probability p (0 < p < 1) is distributed as negative binomial distribution of order k. The present paper generalizes results of SHANE (1973), PHILIPPOU and MUWAFI (1982), and PHILIPPOU, GEORGHIOU and PHILIPPOU (1982).
43 citations
TL;DR: In this paper, the spontaneous precipitation of calcium carbonate from supersaturated solutions was studied in the presence of 1,2-dihydroxy-1-2-bis (DDPE) and Zn 2+ ions, and the experimental conditions were selected in such a way that precipitation in the absence of inhibitors started within time periods from 6 to 85 min.
40 citations
32 citations
Abstract: Cette methode permet de determiner non seulement les coefficients de diffusion mutuelle, mais aussi la reponse molaire relative (detecteur a conductivite thermique) et donc le diametre moleculaire et le volume critique. Exemples: alcanes, alcenes, air, O 2 N 2 , Ar, CO 2
31 citations
TL;DR: In this paper, a generalized quadratric cost function was derived for a class of bilinear closed-loop systems with generalized quadratic cost functions, where the optimal cost function is shown to be a Lyapunov function.
Abstract: Stabilizing and optimizing feedback control policies are derived for the important class of bilinear systems with generalized quadratric cost functions. These policies as well as the resulting optimal costs are quadratic in the state. The optimal cost function is shown to be a Lyapunov function for the bilinear system at hand. The resulting optimal and stabilized closed-loop system is of third order with respect to the state. One illustrative example is included.
31 citations
TL;DR: The modified steroidal alkylating agent 3 beta-hydroxy-13 alpha-amino-13,17-seco-5 alpha-androstan-17-oic-13 17-lactam [p-[bis(2-chloroethyl)amino]phenyl]acetate (NSC 290205) is active in treating the LX-1 lung and MX-1 breast xenografts as well as a number of rodent tumors.
01 Jan 1984
TL;DR: It was revealed that ceratitins are reabsorbed by the fat body and a fraction of them is deposited in the cuticle of Ceratitis capitata.
Abstract: The developmental profile of the major haemolymph proteins (ceratitins) inCeratitis capitata was studied. Ceratitin concentration in the haemolymph decreases dramatically during the last days of pupal life, while the amounts of ceratitins in whole organism extracts remain unchanged. By electrophoretic, immunological and immunofluorescence techniques it was revealed that ceratitins are reabsorbed by the fat body and a fraction of them is deposited in the cuticle. The possible role of ceratitins is discussed.
TL;DR: In this article, the post buckling behavior of a column with a transverse surface crack on the one side is studied, considering the local flexibility because of the crack, and two distinct buckling modes have been identified to closing cracks, because of different behavior of the cracked region in compression and tension or positive and negative bending modes.
TL;DR: A problem of fundamental importance in the design of “self”-organizing systems is the “theoretical minimum” amount of hardware complexity (CH) necessary to drive a given functional repertoire (software complexity CS).
Abstract: A problem of fundamental importance in the design of “self”-organizing systems is the “theoretical minimum” amount of hardware complexity (CH) necessary to drive a given functional repertoire (software complexity CS). In general it is assumed that the curve CH = f(CS) is a monotonically rising one with steepness depending on the specific “wiring mechanism” or the architecture of the given system. This conviction comes traditionally from the communication engineering practice where the act of information processing includes a sequence of an “expansion” and a “contraction” of the dimensionality of the state space, i.e., a proliferation and a subsequent compression of the degrees of freedom of the transmitted message.
TL;DR: In this article, the UO2/Zircaloy-4 (Zry-4) interaction is explained in terms of the total interfacial energy and work of adhesion of the system.
TL;DR: In this paper, the interfacial energy and work of adhesion of various combinations of the materials formed in the UO 2 /Zircaloy-4 (Zry-4) interaction were determined from wettability studies of the following solid/liquid systems: (a) UO2 /U, (b) U OZr(O), (c) OZR(O), (d) α-Zr (O)/U, and (e) Zry 4/U ).
TL;DR: In this paper, the influence of the content of the modifier on the specific surface area of a doped support was examined, and a model taking into account the above observation has been postulated.
TL;DR: In this article, a compositional and genetic relationship exists between the metalliferous sediments and the sulphide deposits, the elucidation of which may lead to the development of a guideline for the location of more sulphides in Ermioni and in other areas.
01 Jan 1984
TL;DR: In this paper, the genesis of some Mn deposits in the Orthrys and Perachora areas is investigated, which are characterized by high concentrations of Mn, low Fe/Mn ratios and low trace metal contents.
Abstract: In this paper the genesis of some Mn deposits in the Orthrys and Perachora areas is investigated. These deposits are characterized by high concentrations of Mn, low Fe/Mn ratios and low trace metal contents. Their chemistry and stratigraphic location suggest that they are syngenetic and have been formed by rapid precipitation from hydrothermal exhalations, related to leaching of magmatic rocks, and which have been discharged onto the sea floor during Triassic-Cretaceous. The fractionation of Fe from Mn is due to its earlier precipitation in the form of sulfides. In the Orthrys area Cu-rich pyrite forms dikes in the diabase underlain the chert horizon with the Mn deposits. The depletion of the Mn deposits in trace metals is due to their absence from the hydrothermal exhalations and to the rapid precipitation of the Mn-phases which did not allow scavenging from the normal sea water. The precipitation of the sulfides within the fractures of the diabase may acted as “filters” absorbing trace metals from the passing hydrothermal solutions. The trace metal concentrations of the Perachora deposits support a greater hydrogenous influence in their formation compared with the Orthrys deposits.
TL;DR: In this paper, the reactions of 1,2-dihydroxy-1, 2-bis(diethoxyphosphinyl)ethane (DBE) with various diisocyanates, such as tolylene diiscyanate, methylenebis(4-phenylisocynate), and hexamethylene-1 6-diisoclynate, were studied for the synthesis of phosphorus-containing polyurethanes.
Abstract: The reactions of 1,2-dihydroxy-1,2-bis(diethoxyphosphinyl)ethane (DBE) with various diisocyanates, such as tolylene diisocyanate, methylenebis(4-phenylisocyanate), and hexamethylene-1,6-diisocyanate, were studied for the synthesis of phosphorus-containing polyurethanes. In addition, DBE and ethyleneglycol or butanediol-1,4 were copolymerized with the diisocyanates. The synthesized poyurethanes were characterized by Fourier transform-infrared (FT-IR), proton nuclear magnetic resonance spectroscopy (1H-NMR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA). Their thermal properties were compared with those of the corresponding common polyurethanes. The fire resistance of the copolyurethanes was evaluated by determining their limiting oxygen index and smoke evolution.
01 Jan 1984
TL;DR: The geographical distribution of the two species (F. obliqua and F. ehrhartii) suggests a vicariation character, and in a new combination F. tuntasia is considered as a synonyme of F. ob liqua.
Abstract: A caryosystematic study of Fritillaria obliqua- complex (F. obliqua, F. tuntasia and F. ehrhartii) endemie in Greece is presented. In a new combination F. tuntasia is considered as a synonyme of F. obliqua. Three populations of F. obliqua (2n = 24 + 0–3B) and three of F. ehrhartii (2n = 24 + 0-lB) are studied cytologically and their karyotypes and idiograms are given. The geographical distribution of the two species (F. obliqua and F. ehrhartii) suggests a vicariation character.
TL;DR: Differences in patterns of proteins suggest that the component areas of the chick blastula have already diverged to different developmental fates before any apparent morphogenetic differentiation, that is, the appearance of the primitive streak.
Abstract: The patterns of protein synthesis are examined in the hypoblast and in the areas that comprise the epiblast, that is, the area opaca, the marginal zone, and the central area, during the blastula stage which marks the beginning of the interaction between the epiblast and hypoblast for induction of the primitive streak. The results demonstrate that there are distinct qualitative and quantitative differences in protein patterns in individual areas of blastoderm, the differences being most distinct between the hypoblast and any of the component areas of the epiblast. These differences in patterns of proteins suggest that the component areas of the chick blastula have already diverged to different developmental fates before any apparent morphogenetic differentiation, that is, the appearance of the primitive streak.
TL;DR: In this paper, a new method is proposed for the derivation of closed-form formulae for the zeros and poles of analytic functions in the complex plane, which makes use of the solution of the simple discontinuity problem.
Abstract: A new method is proposed for the derivation of closed-form formulae for the zeros and poles of sectionally analytic functions in the complex plane. This method makes use of the solution of the simple discontinuity problem in the theory of analytic functions and requires the evaluation of real integrals only (for functions with discontinuity intervals along the real axis). Many transcendental equations of mathematical physics can be successfully solved by the present approach. An application to such an equation, the molecular field equation in the theory of ferromagnetism, is made and the corresponding analytical formulae are reported together with numerical results.
TL;DR: On montre que l'equation maitresse introduite par Caldirola et Lugiato est un cas particulier de l'Equation du mouvement de Heisenberg isotopique admissible de Lie.
Abstract: On montre que l'equation maitresse introduite par Caldirola et Lugiato est un cas particulier de l'equation du mouvement de Heisenberg isotopique admissible de Lie
TL;DR: Immunological and electrophoretic analysis showed that C4 remains intact up to the second day of the adult life of the Mediterranean fruit fly Ceratitis capitata and like the other three major haemolymph proteins seems to be utilized rapidly from the adult flies.
TL;DR: In this article, the stabilization problem via state feedback, for the class of strictly bilinear singularly perturbed systems, is considered, and it is shown that the stabilizing controller of the overall system can be determined by simply.
Abstract: The stabilization problem via state feedback, for the class of strictly bilinear singularly perturbed systems, is considered. It is shown that the stabilizing controller of the overall system can be determined by simply. using the quadratic stabilizing controllers of the fast and slow subsystems. The procedure for computing the two matrix-gains of the controller is given and some illustrative examples are worked out.
TL;DR: In this paper, the pseudotetrahedral [CoX3L]− and [CoY2XL]− anions are present in the solid pyridine and aniline complexes.
Abstract: New complexes of the general types HCoX3 ·nL and HCo Y2X·nL (X=Br, I; Y=Cl, Br, I; L=diethyl ether, pyridine, aniline; n=1, 2, 3 and 4) have been prepared and characterized by elemental analyses, molar conductance measurements, magnetic measurements, spectral (UV, visible, IR and far-IR) data and X-ray powder patterns. All the magnetic and spectroscopic results indicate that pseudotetrahedral [CoX3L]− and [CoY2XL]− anions are present in the solid pyridine and aniline complexes. The data for the solid compounds are compatible with, and lend support to, outer spheres comprising (N[sbnd]H[sbnd]N)+ groups.
TL;DR: In this paper, viscosimetriques sur le polymethacrylate de methyle atactique a 45°C dans l'acetonitrile.
Abstract: Resultats viscosimetriques sur le polymethacrylate de methyle atactique a 45°C dans l'acetonitrile
TL;DR: An exact solution of Schrodinger equation for the problem of a harmonic oscillator of mass varying with time and coordinates is presented in this article, which leads to a new one that relates the damped harmonic oscillators with velocity-depentent interaction problem.
Abstract: An exact solution of Schrodinger equation is presented for the problem of a harmonic oscillator of mass varying with time and coordinates according to \begin{aligned} m(q,t)=m_{0}/\text{e}^{-
u t}-k_{0}^{2}q^{2}. \end{aligned} This case, compared with known types of equivalent interactions, leads again to a new one that relates the damped harmonic oscillator with velocity-depentent interaction problem.