Search results for "formal"
showing 10 items of 1654 documents
Time-dependent Landauer-B\"uttiker formalism for superconducting junctions at arbitrary temperatures
2015
We discuss an extension of our earlier work on the time-dependent Landauer--B\"uttiker formalism for noninteracting electronic transport. The formalism can without complication be extended to superconducting central regions since the Green's functions in the Nambu representation satisfy the same equations of motion which, in turn, leads to the same closed expression for the equal-time lesser Green's function, i.e., for the time-dependent reduced one-particle density matrix. We further write the finite-temperature frequency integrals in terms of known special functions thereby considerably speeding up the computation. Numerical simulations in simple normal metal -- superconductor -- normal m…
Mössbauer studies on tin(IV) and organotin(IV) diacetylbis(benzoylhydrazone) complexes
1974
Abstract The Mossbauer parameters of Ph 2 SnDB, PhClSnDB and Sn(DB) 2 were determined, where DB 2− is the dianion of the multidentate ligand diacetylbis(benzoylhydrazone). According also to data treatment with the point charge model formalism, the configurations of Ph 2 Sn IV and PhSn IV derivatives appear to be essentially octahedral, with linear CSnC and CSnCl skeletons. As to Sn(DB) 2 , it appears that the electrical charge density at the Sn IV nucleus has a cubic symmetry, which is consistent with both tetrahedral and octahedral configurations around Sn IV .
Extracting Formal Models from Normative Texts
2016
Normative texts are documents based on the deontic notions of obligation, permission, and prohibition. Our goal is model such texts using the C-O Diagram formalism, making them amenable to formal analysis, in particular verifying that a text satisfies properties concerning causality of actions and timing constraints. We present an experimental, semi-automatic aid to bridge the gap between a normative text and its formal representation. Our approach uses dependency trees combined with our own rules and heuristics for extracting the relevant components. The resulting tabular data can then be converted into a C-O Diagram.
Resorcinol Functionalized Gold Nanoparticles for Formaldehyde Colorimetric Detection
2019
[EN] Gold nanoparticles functionalized with resorcinol moieties have been prepared and used for detecting formaldehyde both in solution and gas phases. The detection mechanism is based on the color change of the probe upon the aggregation of the nanoparticles induced by the polymerization of the resorcinol moieties in the presence of formaldehyde. A limit of detection of 0.5 ppm in solution has been determined. The probe can be deployed for the detection of formaldehyde emissions from composite wood boards.
Unambiguous recognizable two-dimensional languages
2006
We consider the family UREC of unambiguous recognizable two-dimensional languages. We prove that there are recognizable languages that are inherently ambiguous, that is UREC family is a proper subclass of REC family. The result is obtained by showing a necessary condition for unambiguous recognizable languages. Further UREC family coincides with the class of picture languages defined by unambiguous 2OTA and it strictly contains its deterministic counterpart. Some closure and non-closure properties of UREC are presented. Finally we show that it is undecidable whether a given tiling system is unambiguous.
Weak and strong recognition by 2-way randomized automata
1997
Languages weakly recognized by a Monte Carlo 2-way finite automaton with n states are proved to be strongly recognized by a Monte Carlo 2-way finite automaton with no(n) states. This improves dramatically over the previously known result by M.Karpinski and R.Verbeek [10] which is also nontrivial since these languages can be nonregular [5]. For tally languages the increase in the number of states is proved to be only polynomial, and these languages are regular.
Block-Deterministic Regular Languages
2001
We introduce the notions of blocked, block-marked and blockdeterministic regular expressions. We characterize block-deterministic regular expressions with deterministic Glushkov block automata. The results can be viewed as a generalization of the characterization of one-unambiguous regular expressions with deterministic Glushkov automata. In addition, when a language L has a block-deterministic expression E, we can construct a deterministic finite-state automaton for L that has size linear in the size of E.
Formal operations and postformal reasoning: A replication
1991
The relationship between formal operations and postformal reasoning was examined by using the Shayer (1978) chemicals problem to assess formal operations and the Commons, et al. (1982) four-story problem to measure postformal reasoning. The subjects were 35 undergraduate social science and humanities students. None of the subjects who were classified as concrete operational or transitional on the chemicals task showed postformal reasoning. The hypothesis that full format operations are a necessary condition of post-formal reasoning and the expectation that subjects showing full formal operations are more likely than others to exhibit postformal reasoning was not supported.
Formal Variation and Language Change in Catalan Quantifiers : the Role of Pragmatics
2020
This article studies the formal variation of the masculine singular forms of the quantifiers u/un 'one', algú/algun 'someone, some', ningú/ningun 'no-one, anyone, not one, any, none' and cada u/cada un 'everyone, each one' in contemporary Catalan. The standard uses of these forms are contrasted with dialectal uses, obtained from a thorough search in oral and written corpora. In addition, they are compared with the uses in the other Romance languages and with their historical evolution in Catalan. The whole set of data, and especially the dialectal information on the Valencian area, allow us to explain the various factors that have interacted in the variation and formal change of these quant…
Circolazione e sviluppo di un modello metodologico. La critica testuale delle fonti giuridiche romane fra Otto Gradenwitz e Salvatore Riccobono
2018
La ricerca delle interpolazioni, cominciata con la Scula culta, viene ripresa in Germania alla fine del XIX secolo. Fra quanti misero a punto un metodo storico-critico per lo studio delle fonti giuridiche romane va menzionato anche Gradenwitz, che – insieme ad altri studiosi tedeschi – sarebbe stato uno dei maestri di Riccobono. La prima produzione scientifica di Riccobono, che si riconosce nel nuovo indirizzo storico-critico affermatosi in Germania, si avvale dei metodi appresi dai maestri tedeschi. Lungo questo solco, tuttavia, comincia l’elaborazione di un metodo più raffinato, che distingue fra interpolazioni formali e interpolazioni sostanziali e recupera gradualmente altri strumenti d…