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Copyright of Calcolo is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcolo is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcolo is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the first two sections of this paper existence theorems are proved for optimal control problems described either by Fredholm systems of integral equations (with control appearing nonlinearly) on a given (possibly infinite) measure space, eventually in presence of eigenvalues, or by Urysohn systems, both with pointwise and integral constraints on controls and states. Controllability is assumed throughout the paper. In the last section necessary conditions are proved for optimal controls of Fredholm systems (a minimum principle in pointwise, or « differential » form), and theorems (that seem to be new also for the corresponding ordinary differential control systems) are deduced about bang-bang and regularization properties of the optimal control (s) (which turns out to be a continuous function except for a finite number of points, if positivity and semicontinuity assumptions hold about the data): in some particular cases the optimal control will be piecewise constant. All these results are independent on the known ones. [ABSTRACT FROM AUTHOR]

Copyright of Annali di Matematica Pura ed Applicata is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Pure & Applied Geophysics is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper contains the doscription of a method of computation of the power spectrum of a stochastic signal that minimizes the error intrinsic with the direct way of computation. The method is a generalization of the mean value rejection and prewhitening techniques. It grounds itself on the adaptive construction of a filter which transforms the true spectrum in a white one by means of the linear filtering of the signal given, whichever the true spectrum may be. The method is suitable of automatic computation in digital form. Various examples of the results obtained by means of a Fortran IV program, also given in the paper, are furnished and discussed. [ABSTRACT FROM AUTHOR]

In a previous paper the numerical solution of a particular boundary-value problem for the «weakly linear» equation was obtained and the convergence of a suitable finite-difference scheme was proved. This paper is concerned with the more general equation where; the solution is obtained using the same finite-difference scheme as in the previous paper, and sufficient condition for its convergence are given for this new case [ABSTRACT FROM AUTHOR]

This paper deals with the language PREFOR, an extention of FORTRAN IV which allows to represent with single identifiers sets of data widely arbitrary and of variable length, The language allows to act upon the sets and upon FORTRAN variables by means of programme defined operators. The declarations of the new operands and operators are added to FORTRAN statements as well as executable statements, describing the calculations upon such elements and FORTRAN expressions, and other organizing statements concerning the dynamic storage assignement required by the variable length operands. Furthermore, referring to the characteristics of dynamic storage organization upon which the language is based, the paper shows the rules for the translation of a PREFOR programme into a FORTRAN programme which can be compiled and executed as usual. Finally a programme is described which can perform this translation upon the IBM 7040 and 7090 and the UNIVAC 1108 processors. [ABSTRACT FROM AUTHOR]

Copyright of Calcolo is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Some authors have proved that a minimal two-level NAND or NOR network can be obtained by the convetional procedures for determining minimal normal forms. But when either the complements of some input variables are not available or the gates have a limited number of inputs, the two-level synthesis is generally impossible; and no procedure has been described for the minimal sunthesis of networks having more than two levels of gates. In this paper some new procedures are described for the synthesis of NAND or NOR networks having more than two levels of gates. In the first sections the properties are briefly described, by which a NAND or NOR expression is equivalent to a conventional expression containing only the AND and OR operators; also, the problem of determining a minimal two-level NAND or NOR network is summarized. Then the synthesis of three-level NAND or NOR networks is considered, in case that both the true and complemented values of input variables are available, and the gates can have an unlimited number of inputs (condition 1). A new procedure is described which makes it possible to find one of the minimal NAND or NOR networks, having a tree-shaped structure, and which gives also quasi-minimal solutions for the general case in which the output of a gate can be connected to the inputs of more than one gate of the next level. The procedure derives from the methods described in a preceding paper by the present author for determining the minimal «sums of products of sums» of an assigned function; but some properties and the particular definition of cost make it possible to apply a computation technique, which simplifies this problem considerably. Then the synthesis problem is considered when the gates can have an unlimited number of inputs but the complements of some of the input variables are not available (condition 2). In this case the two-level synthesis is generally impossible (a simple necessary and sufficient condition for a two-level solution to exist is proved); on the contrary, a three-level NAND or NOR network always exists, which implements the assigned function. This network can be determined with the procedure which has been described for determining the minimal three-level networks in condition 1, but the new conditions simplify the problem and a remarkable reduction of the computation work is possible. Lastly the following cases are considered: In these cases a two- or a three-level synthesis may be impossible, but one can always verify whether a two- or a three-level network implementing the assigned function exists. However a simple procedure is described, which always makes it possible to find a quasi-minimal solution characterized by more than three levels of gates. [ABSTRACT FROM AUTHOR]

Copyright of Ricerca in Clinica E in Laboratorio is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annali dell'Universita di Ferrara: Sezione VII-Scienze Mathematiche is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annali dell'Universita di Ferrara: Sezione VII-Scienze Mathematiche is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annali dell'Universita di Ferrara: Sezione VII-Scienze Mathematiche is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of this paper is to study a class of metric spaces over a field of characteristic > 2 and the groups of their motions. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to construct a class of metric spaces, with a weak structure of incidence, over a field of characteristic > 2. [ABSTRACT FROM AUTHOR]

In this paper, boundary-value problems for degenerate elliptic parabolic operators of order 2m are discussed. An existence theorem is proved, with the help of a non trivial induction argument (substantially, with respect to the order of certain derivatives) and of a « small parameter-method ». [ABSTRACT FROM AUTHOR]

In [2] and [3] elliptic boundary value problems in a plane sector were investigated within certain Sobolev weight spaces W,s and W,s (see [1]), with the exception of some well-defined values of s − r + 1 and s − r + 1. This paper is concerned with such boundary value problems when s − r + 1 or s − r + 1 are exceptional values. [ABSTRACT FROM AUTHOR]

In this paper we continue our investigations (see [2] and [3]) devoted to elliptic boundary value problems in a plane sector. In [2] Sobolev weight spaces $$W_{s_1 ,s_2 }^r$$ and $$W_{s_1 ,s_2 }^{*r}$$ were discussed. In [3] the above mentioned boundary value problems in the case of homogeneous constant coefficient operators and within the Sobolev weight spaces $$W_{s_1 ,s_2 }^r$$ were investigated. This third part of the work is concerned with the problem for general operators, within the Sobolev weight spaces $$W_{s_1 ,s_2 }^r$$ and $$W_{s_1 ,s_2 }^{*r}$$ . Existence theorems and stability theorems for nullity, deficiency, index have been proved and examples are given. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to give a group representation of the metric planes over the real numbers (exactly the elliptic plane, the hyperbolic plane, the DeSitter plane, the euclidean plane and the Minkowski plane) on the elliptic and hyperbolic inversive planes by inversions and their transformations. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to represent a class of metric spaces on the elliptic and hyperbolic inversive planes by inversions and their transformations. [ABSTRACT FROM AUTHOR]

Let P be a sequence of optimal control problems with fixed end times (described by ordinary differential equations, with pointwise and norm (of controls) constraints, and with general functional). Let P be an « unperturbed » problem (of the same type). In this paper theorems are obtained about the strong convergence (in some L) of optimal controls of P to some optimal control of P, about the uniform convergence x → x of states, and the property that min P min P. As corollaries, convergence theorems for some calculus of variations problems can be derived. Weak convergence theorems of optimal controls of P to an optimal one of P were considered in [7]. A general abstract theorem about strong convergence of minimum points, generalizing a result in [5], is proved. [ABSTRACT FROM AUTHOR]

In this paper, concerning the study of graded algebras integral over graded rings and the contraction of the non-irrelevant maximal ideals, we prove the following result: every graded algebra which is integral over a Jacobson graded ring is a Jacobson graded ring. [ABSTRACT FROM AUTHOR]

Copyright of Calcolo is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcolo is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcolo is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Rabins cut-point theorem gives some conditions on acceptance of a probabilistic langnage by a finite state automaton. In the present, paper we will generalize Rabin's results by studying the possibility of reducing a coutext-free or right-linear grammar with infinite non-terminal symbols to an equivalent grammar with a finite number of non-terminal symbols. We will show that reducibility is related to some topological properties of non-terminal symbols, which we will consider as a metric space. Finally, as an application, we will use the above methods in the study of certain classes of weighted languages. [ABSTRACT FROM AUTHOR]

Copyright of Calcolo is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcolo is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ricerca in Clinica E in Laboratorio is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ricerca in Clinica E in Laboratorio is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ricerca in Clinica E in Laboratorio is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

It is possible to detect and dose Psylocibine, a psychoneurotropic substance occurring in Psilocybe, Stropharia, Panaeolus etc., with a reaction already used to detect Tryptophane and indole-auxins (6) (7) (8) (9). This method is more sensitive than U.V. measurement and Keller's reaction (4) (see fig. 3). Optical density is proportional to concentration from 0,005 to 0,050 µmoles per ml when measured in a 1 cm cell in the Beckman spectrophotometer. Tryptophane, indole-auxins and 2-deoxy-sugars could interfere (6) (7) (8) (9) (10). procedure: In a test tube are pipetted: The absorption spectrum of the chromophore exhibits a maximum at 512 m µ (see fig. 2). The ratio E in the reaction mixture/E in U.V. is about 1,9 and differs from other indole-derivatives. (see Tab. II). The reaction can also be employed to detect and dose Psylocibine-spots in paper and thin-layer chromatography spraying with the following mixture prepared just before use: fructose g 1.0 cysteine hydrochloride g 1.0 3 N HSO ml 100 Paper - chromatograms are dried in an oven (70°C) for 5 minutes, chromatoplates for 10-15 minutes. Psylocibine appears as a pink spot. [ABSTRACT FROM AUTHOR]

Copyright of Mycopathologia et Mycologia Applicata is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mycopathologia et Mycologia Applicata is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annali dell'Universita di Ferrara: Sezione VII-Scienze Mathematiche is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annali dell'Universita di Ferrara: Sezione VII-Scienze Mathematiche is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annali dell'Universita di Ferrara: Sezione VII-Scienze Mathematiche is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annali dell'Universita di Ferrara: Sezione VII-Scienze Mathematiche is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Zeitschrift Für Zellforschung und Mikroskopische Anatomie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We pose the problems, that are in the title, for functions u(x) from Λ=R\{( 0, 0)} into a Banach space B: such functions are required to satisfy asintotical conditions for |x| → 0 and |x| → + ∞. Existence and uniqueness theorems are proved (no. 5) and the regularity of C type up to vertex of Λ is discussed (no. 6). The main treatment is the study about an integral function g joined with operators which define the differential conditions (no. 3). This function arises from the transformation of those problems by using a rapresentation's formula stated in the previous paper [ 1]. [ABSTRACT FROM AUTHOR]

In this paper we define quasi étale ring homomorphisms, as a generalization of étale ones, and we show that if ϕ: A→B is a quasi étale homomorphism of noetherian rings, and A is excellent, then B is excellent. The converse is not always true; however we show that if ϕ is faithfully flat and regular (in particular qnasi étale), if A is universally catenarian and B is excellent, then A is excellent. The above statements can be applied when B is the henselization of A with respect to an ideal; and from this it follows that a Hensel pair is a direct limit of excellent ones. [ABSTRACT FROM AUTHOR]

We are concerned with non-variational boundary value problems, with omogeneus boundary conditions, for linear partial differential equations of quasi-elliptic type in a bounded domain Θ in R. It is well known that some of difficulties which arise in treating such problems, in comparison with « regular » elliptic problems, are connected with the presence of angular points in Θ: let us point out with B. Pini [32] that « a bounded domain for which it is possible to assign a correct boundary value problem for a quasi-elliptic but not elliptic equation always has angular points ». We suppose Θ is a cartesian product of a finite number of open sets and, in order to overcome the difficulties attached to the presence of angular points in Θ, taking as a model the two previous papers [33], [34] devoted to elliptic problems with singular data, we investigate the problem within suitable Sobolev weight spaces, connected with the angular points of Θ and included in the ones we have studied in [35]. Within such spaces we get existence and uniqueness theorems. [ABSTRACT FROM AUTHOR]

Some remarks and an errata concerning a previous paper. [ABSTRACT FROM AUTHOR]

In this paper the well known theorems of E.A. Barbaschin-N.N. Krasovskij and J. P. LaSalle on asymptotic statility and instability are extended to partial stability. An application is given for a class of non-holonomic dissipative mechanical systems. [ABSTRACT FROM AUTHOR]

In this paper the Author proves the Holder-continuity of the weak solutions of the problems P, P and P (see Introduction) expressed by variational inequalities. [ABSTRACT FROM AUTHOR]