The main result of this paper belongs to the field of the comparative study of program verification methods as well as to the field called nonstandard logics of programs. We compare the program verifying powers of various well-known temporal logics of programs, one of which is the Intermittent Assertions Method, denoted as Bur. Bur is based on one of the simplest modal logics called S5 or sometime-logic. We will see that the minor change in this background modal logic increases the (...) program verifying power of Bur. The change can be described either technically as replacing the reflexive version of S5 with an irreflexive version, or intuitively as using the modality some-other-time instead of sometime. Some insights into the nature of computational induction and its variants are also obtained. (shrink)

The class \ of t rue p airing a lgebras is defined to be the class of relation algebras expanded with concrete set theoretical projection functions. The main results of the present paper is that neither the equational theory of \ nor the first order theory of \ are decidable. Moreover, we show that the set of all equations valid in \ is exactly on the \ level. We consider the class \ of the relation algebra reducts of \ ’s, (...) as well. We prove that the equational theory of \ is much simpler, namely, it is recursively enumerable. We also give motivation for our results and some connections to related work. (shrink)

In this paper we investigate total correctness in Nonstandard Dynamic Logic . Here we show that despite of the celebrated Kfoury-Park [5] result, termination is a rst order notion if approached properly.

Biró, B. and I. Sain, Peano arithmetic as axiomatization of the time frame in logics of programs and in dynamic logics, Annals of Pure and Applied Logic 63 201-225. We show that one can prove the partial correctness of more programs using Peano's axioms for the time frames of three-sorted time models than using only Presburger's axioms, that is it is useful to allow multiplication of time points at program verification and in dynamic and temporal logics. We organized the (...) paper as follows: 1. Preliminaries, 2. The main result, 3. Peano arithmetic with bounded multiplication, 4. Connections with temporal logics and dynamic logics, Acknowledgements, References. (shrink)

We give an overview of decidability results for modal logics having a binary modality. We put an emphasis on the demonstration of proof-techniques, and hope that this will also help in finding the borderlines between decidable and undecidable fragments of usual first-order logic.

The class $$\mathsf{TPA}$$ TPA of t rue p airing a lgebras is defined to be the class of relation algebras expanded with concrete set theoretical projection functions. The main results of the present paper is that neither the equational theory of $$\mathsf{TPA}$$ TPA nor the first order theory of $$\mathsf{TPA}$$ TPA are decidable. Moreover, we show that the set of all equations valid in $$\mathsf{TPA}$$ TPA is exactly on the $$\Pi ^1_1$$ Π 1 1 level. We consider the class $$\mathsf{TPA}^-$$ (...) TPA - of the relation algebra reducts of $$\mathsf{TPA}$$ TPA ’s, as well. We prove that the equational theory of $$\mathsf{TPA}^-$$ TPA - is much simpler, namely, it is recursively enumerable. We also give motivation for our results and some connections to related work. (shrink)

Theorem 1 states a negative result about the classical semantics j= ! of program schemes. Theorem 2 investigates the reason for this. We conclude that Theorem 2 justies the Henkin-type semantics j= for which the opposite of the present Theorem 1 was proved in [1]{[3] and also in a dierent form in part III of [5]. The strongest positive result on j= is Corollary 6 in [3].

We contrast two positions concerning the initial domain of actions that infants interpret as goal-directed. The 'narrow scope' view holds that goal-attribution in 6- and 9-month-olds is restricted to highly familiar actions (such as grasping) (). The cue-based approach of the infant's 'teleological stance' (), however, predicts that if the cues of equifinal variation of action and a salient action effect are present, young infants can attribute goals to a 'wide scope' of entities including unfamiliar human actions and actions of (...) novel objects lacking human features. It is argued that previous failures to show goal-attribution to unfamiliar actions were due to the absence of these cues. We report a modified replication of showing that when a salient action-effect is presented, even young infants can attribute a goal to an unfamiliar manual action. This study together with other recent experiments reviewed support the 'wide scope' approach indicating that if the cues of goal-directedness are present even 6-month-olds attribute goals to unfamiliar actions. (shrink)

Documents, in particular identity cards, mediate relationships between individuals and institutions. Their materiality matters and actively impacts how states govern populations and their movements. In this paper, I examine one such object, the Romanian identity card. Focusing on its temporality and agency, I explore how objects and technological procedures enact race. In Romania, people without an address or proof of residence—many of them members of segregated Roma communities living in deep poverty—can only receive a temporary identity card, the Carte de (...) Idenititate Provizorie (CIP). CIP holders do not enjoy full citizenship and are deprived of various rights, such as the right to travel without a passport within the European Union. They are also exposed to heightened surveillance as they must apply annually for a new CIP. Starting from the material object of the CIP, I explore how race comes into being as a relation at the intersection of various temporalities that are folded into the rules and bureaucratic practice entailed in its issue. I offer the concept of “permanent temporality” to analyze how racialization occurs in practices of governing people and their movement in Europe. (shrink)

Prispevek obravnava potek in zaporedje dogodkov, preko katerih se Medeja pomladi – tako kot je pred seboj pomladila druge, to stori, kot bi se preprosto razstavila in se dala v svoj kotel ter se nato prerodila v svoj mlajši in močnejši jaz. Članek najprej predstavi različne in spreminjajoče se ženske vloge pri Senekovi Medeji, nato pa s pomočjo podrobnega branja besedila pokaže, kako Seneka uporablja podobe telesa, in se osredotoči na način, kako Medeja uporablja lastno telo, da bi dosegla svojo (...) preobrazbo: da bi začela novo življenje z vrnitvijo k svojemu prejšnjemu jazu, da bi se torej pomladila. V podporo tej tezi članek izpostavi tudi njena prejšnja pomlajevanja, kot so ohra­njena v besedilnih in ikonografskih virih, ter pokaže, kako je Seneka Medejo predstavil kot precej pozitiven lik, kot božanstvo, čarodejko in zdravilko, ki zmore upravljati z življenjem in smrtjo. (shrink)

After identifying points of agreement between Karl Rahner and Hans Urs von Balthasar on topics raised by Dr. Sain’s essay, this response raises questions about the deeper foundations of the substantial differences between them. It suggests that the appeal to contrast in their starting-points (Goethe versus Kant) as an explanation is not adequate and suggests lines of further inquiry which might be pursued further.

As the number of consumer transgressions continues to increase, so do their financial repercussions for companies. Though academic and managerial interest in addressing this issue is growing, research on how to dissuade consumers from committing transgressions remains scarce. Drawing on the mental imagery literature and normative moral theory, the present research examines a novel way of reducing consumers’ appraisals of their own transgressions. Whereas an actor-imagery perspective fosters a teleological, egoistic view of morality and, in turn, induces moral leniency, having (...) consumers adopt an observer-imagery perspective fosters a deontological view of morality and, in turn, induces moral stringency. The effects are robust across various types of consumer transgressions, including the purchase of counterfeit products and return fraud in the form of wardrobing. Study 2 also rules out vividness as an alternative explanation for these effects. Theoretical and managerial implications are discussed. (shrink)

Ion channels mediate ion flux across biological membranes and regulate important organellar and cellular tasks. A recent study revealed the presence of four new proteins, the MIM complex (composed by Mim1 and Mim2), Ayr1, OMC7, and OMC8, that are able to form ion‐conducting channels in the outer mitochondria membrane (OMM). These findings strongly indicate that the OMM is endowed with many solute‐specific channels, in addition to porins and known channels mediating protein import into mitochondria. These solute‐specific channels provide essential pathways (...) for the controlled transport of ions and metabolites and may thus add a further layer of specificity to the regulation of mitochondrial function at the organelle‐cytosol and/or inter‐organellar interface. Future studies will be required to fully understand the way(s) of regulation of these new channels and to integrate them into signaling pathways within the cells. (shrink)

A fiatal kutató a szociológiai értelemben vett segítés elméletével és gyakorlatával foglalkozik, s ezen belül is egyrészt azzal, hogy adott helyzetben miként jönnek létre az ún. jóról alkotott elképzelések, másrészt a kisebbségi magyarok segítésének elképzeléseiből miként erednek konkrét civil cselekvések, és ezek hogyan teremtik újra a résztvevők nemzet- és magyarságképét, harmadszor pedig górcső alá kerül a civil segítés hatalmi dimenziója. A bevezetőt követően olyan témákat érint a szerző, mint a jótékonyság modelljei, az "érdemesség" szerepe, a segítő-segített pozíciók aszimmetriája (hatalom újratermelésének (...) modelljei, elismerés és jótékonykodás, hatalom a jótékonyság elméleti modelljeiben), a kisebbségi magyarok támogatásának intézményes keretei, illetve a módszertan (programok kiválasztása, alkalmazott módszerek). ***A folytatásban olvashatunk négy konkrét programról, a segítés ideológiájáról és azok újratermeléséről (hiány és érdemesség toposzai, rítusok, "másság", érdemesség fenntartása és újraalkotása), az elismerés korlátairól és lehetőségeiről, valamint a gondoskodás és intimitás jótékonyságban játszott szerepéről. A szakkönyv a következtetések összegzésével, és a felhasznált irodalom felsorolásával zárul. A kötet az Ünnepi Könyvhét alkalmából jelenik meg. "www.kello.hu © minden jog fenntartva". (shrink)

En el siguiente trabajo me encargaré de estudiar la noción de cuerpo en el Banquete de Platón a partir del discurso de Aristófanes, pretendiendo con esto revisar al mismo tiempo la tradicional lectura del diálogo —que hace foco únicamente en el personaje de Sócrates— y la interpretación más aceptada del lugar que ocupa el cuerpo en el pensamiento platónico —el cual es relegado a una esfera de negatividad aparentemente insalvable. En una primera parte mostraré que Aristófanes, en tanto poeta, busca (...) elementos a la mano para inspirar su relato; elementos que encuentra en su interacción con el médico Erixímaco. A partir de esto, Aristófanes tejerá un esquema conceptual con nociones médicas en el que el cuerpo cobrará el rol de «síntoma», i.e expresión visible, de un estado enfermo y corrompido. Como conclusión, la idea de cuerpo como «síntoma» resultará para la lectura propuesta un indicio de que Platón presenta en el Banquete al cuerpo de manera positiva como despertador de un deseo que estimulará la búsqueda hacia la verdad. (shrink)

The central question of Hans Urs von Balthasar’s Theo-Logic is how the infinite truth of God can be manifested in the finite structures of the created world. In the course of answering this question, Balthasar presents a philosophical understanding of expressive form and a theology of Christ as the expression of divine truth in the world. The philosophical discussion of truth provides support for the intelligibility of the theological claim that God’s truth has been manifested in the world in Christ. (...) The fullest expression of divine truth and the highest realization of worldly truth are found together in Christ, whom Balthasar calls the “truth of God.” Balthasar’s philosophical and theological understanding of expression, as set forth in the Theo-Logic, provides helpful insights for comparing his thought to that of Karl Rahner. (shrink)

Collaborative filtering recommender system (CFRS) plays a vital role in today’s e-commerce industry. CFRSs collect ratings from the users and predict recommendations for the targeted product. Conventionally, CFRS uses the user-product ratings to make recommendations. Often these user-product ratings are biased. The higher ratings are called push ratings (PRs) and the lower ratings are called nuke ratings (NRs). PRs and NRs are injected by factitious users with an intention either to aggravate or degrade the recommendations of a product. Hence, it (...) is necessary to investigate PRs or NRs and discard them. In this work, opinion mining approach is applied on textual reviews that are given by users for a product to detect the PRs and NRs. The work also examines the effect of PRs and NRs on the performance of CFRS by evaluating various measures such as precision, recall, F-measure and accuracy. (shrink)

We show the undecidability of the equational theories of some classes of BAOs with a non-associative, residuated binary extra-Boolean operator. These results solve problems in Jipsen [9], Pratt [21] and Roorda [22], [23]. This paper complements Andréka-Kurucz-Németi-Sain-Simon [3] where the emphasis is on BAOs with an associative binary operator.

Pietraszewski's model – though promising in many respects – needs to be extended so that it can explain the multitude of rich inferences that people draw from group membership. In this commentary, we highlight some facets of group thinking, especially from the field of developmental psychology, that cannot be unambiguously accounted for by a model that is built solely on relational cues.

Ethnic prejudice can lead to exclusion and hinder social integration. Prejudices are formed throughout socialization, and social norms inform individuals about the acceptability of prejudice against certain outgroups. Adolescence is a crucial period for the development of intergroup attitudes, and young people are especially prone to follow the norms they perceive in their reference groups. At the same time, the effect of perceived norms on prejudice in school classes has been rarely studied. In Hungary, where prejudice against the Roma is (...) widespread and there is no clear social norm proscribing prejudiced manifestations, this topic is especially relevant. In the present paper, based on multi-level analyses of panel data from Hungarian ninth-graders, we find that adolescents adjust their attitudes to those they perceive to be dominant among their classmates and that classmates serve as more important reference groups than teachers do. More contact with Roma is found to be associated with less prejudice against them. Looking at school classes, we find that at the beginning of the school year, many students underestimate the rejection of prejudiced expressions in their classes. By the end of the year, many students are found to adjust their own attitudes to the falsely perceived class norm. Based on our findings, we argue that school classes should be treated as important normative contexts for the socialization of intergroup attitudes and should receive special attention from both scholars and practitioners working in the fields of prejudice research and reduction. Furthermore, we suggest that teachers can most successfully hinder prejudices by working on a common, visible, shared class norm rather than “teaching” students that prejudices are not acceptable. (shrink)

We prove that the equational theory of a semigroups becomes undecidable if we add a semilattice structure with a ‘touch of symmetric difference’. As a corollary we obtain that the variety of all Boolean algebras with an associative binary operator has a ‘hereditarily’ undecidable equational theory. Our results have implications in logic, e.g. they imply undecidability of modal logics extending the Lambek Calculus and undecidability of Arrow Logics with an associative arrow modality.

Recommender system depends on the thoughts of numerous users to predict the favourites of potential consumers. RS is vulnerable to malicious information. Unsuitable products can be offered to the user by injecting a few unscrupulous “shilling” profiles like push and nuke attacks into the RS. Injection of these attacks results in the wrong recommendation for a product. The aim of this research is to develop a framework that can be widely utilized to make excellent recommendations for sales growth. This study (...) uses the methodology that presents an enhanced clustering algorithm named as modified density peak clustering algorithm on the consumer review dataset to ensure a well-formed cluster. An improved recurrent neural network algorithm is proposed to detect these attacks in hybrid RS, which uses the content-based RS and collaborative filtering RS. The results are compared with other state of the art algorithms. The proposed method is more suitable for E-commerce applications where the number of customers and products grows rapidly. (shrink)