Logical Dependencies Research Articles

Negation and partial axiomatizations of dependence and independence logic revisited

In this paper, we axiomatize the negatable consequences in dependence and independence logic by extending the systems of natural deduction of the logics given in [22] and [11]. We prove a characterization theorem for negatable formulas in independence logic and negatable sentences in dependence logic, and identify an interesting class of formulas that are negatable in independence logic. Dependence and independence atoms, first-order formulas belong to this class. We also demonstrate our extended system of independence logic by giving explicit derivations for Armstrong's Axioms and the Geiger-Paz-Pearl axioms of dependence and independence atoms.

The expressive power of k-ary exclusion logic

In this paper we study the expressive power of k-ary exclusion logic, EXC[k], that is obtained by extending first order logic with k-ary exclusion atoms. It is known that without arity bounds exclusion logic is equivalent with dependence logic. By observing the translations, we see that the expressive power of EXC[k] lies in between k-ary and (k+1)-ary dependence logics. We will show that, at least in the case when k=1, both of these inclusions are proper.In a recent work by the author it was shown that k-ary inclusion-exclusion logic is equivalent with k-ary existential second order logic, ESO[k]. We will show that, on the level of sentences, it is possible to simulate inclusion atoms with exclusion atoms, and in this way express ESO[k]-sentences by using only k-ary exclusion atoms. For this translation we also need to introduce a novel method for “unifying” the values of certain variables in a team. As a consequence, EXC[k] captures ESO[k] on the level of sentences, and we obtain a strict arity hierarchy for exclusion logic. It also follows that k-ary inclusion logic is strictly weaker than EXC[k].Finally we use similar techniques to formulate a translation from ESO[k] to k-ary inclusion logic with an alternative strict semantics. Consequently, for any arity fragment of inclusion logic, strict semantics is strictly more expressive than lax semantics.

Characterising modal definability of team-based logics via the universal modality

We study model and frame definability of various modal logics. Let ML(u⃞+) denote the fragment of modal logic extended with the universal modality in which the universal modality occurs only positively. We show that a class of Kripke models is definable in ML(u⃞+) if and only if the class is elementary and closed under disjoint unions and surjective bisimulations. We also characterise the definability of ML(u⃞+) in the spirit of the well-known Goldblatt–Thomason theorem. We show that an elementary class F of Kripke frames is definable in ML(u⃞+) if and only if F is closed under taking generated subframes and bounded morphic images, and reflects ultrafilter extensions and finitely generated subframes. In addition we study frame definability relative to finite transitive frames and give an analogous characterisation of ML(u⃞+)-definability relative to finite transitive frames. Finally, we initiate the study of model and frame definability in team-based logics. We study (extended) modal dependence logic, (extended) modal inclusion logic, and modal team logic. We establish strict linear hierarchies with respect to model definability and frame definability, respectively. We show that, with respect to model and frame definability, the before mentioned team-based logics, except modal dependence logic, either coincide with ML(u⃞+) or plain modal logic ML. Thus as a corollary we obtain model theoretic characterisation of model and frame definability for the team-based logics.This article subsumes and extends the conference articles [30] and [31].

CONTEXT AWARENESS FRAMEWORK FOR DEVELOPING MOBILE APPLICATIONS: A SURVEY OF SELECTED SMALL AND MEDIUM ENTERPRISES IN NAKURU TOWN, KENYA

Mobile applications act as valuable tools that can be used by entrepreneurs and small and medium enterprises (SMEs) alike to market their products/services and considerably reduce costs of doing business. The government of Kenya has invested billions of shillings in laying of fiber optic cables in Kenya, improving Kenya‘s ICT sector and coming up with projects aimed at promoting the use of technology among businesses and citizens alike. With all of these investments, there are challenges that hinder the use of business mobile applications by SMEs. Although context awareness in mobile applications is gaining recognition among mobile user and developer communities, many design scenarios still do not incorporate required context awareness as one of their primary goals. Although there are strong context awareness frameworks for mobile applications, there is still potential to improve the usability of virtual learning systems. The study established that the concept of context independence including the physical context independence and the logical context independence from the applications and mobile devices provides a graceful solution in the form of a methodological framework for the development of context-aware systems for SMEs in Nakuru Town.

Framing transformation dynamics towards service-orientation: alternative trajectories of B2B relations

This article examines dynamics of complex transformation in value creation logics in business-to-business (B2B) relationships. Based on the literature of servitisation, relationship marketing, and particularly the service-dominant (S-D) logic approach, an integrative conceptual framework for structuring provider-customer interaction is built. The framework combines strategic and operational aspects and the perspectives of both parties. It is applied empirically in a multiple case study covering different industries. The results reveal the alternative and parallel trajectories in the B2B relations of the companies, instead of the previous unidirectional transition approach of servitisation. Furthermore, relating to the topical S-D logic debate, the results indicate that the transformation from goods-dominant logic towards service-dominant logic has been built in as different trajectories. The conceptual framework explicates transformation dynamics in terms of value creation logic and mutual dependence between parties. It facilitates particularly SMEs considering relationship-specific evaluation and development, as well as strategic re-positioning and value constellations.

Factors Influencing Student Satisfaction in Higher Education. The Case of a Georgian State University

With the increasing importance, higher education is considered as a major asset for any nation’s socio-economic and technological development. The quality of education offered by the higher education institutions directly impacts country’s performance. That is why, number of scientific researches and public reports and debates agrees on the importance of the quality management in higher education. There is also an important debate on a link between the service quality and students’ satisfaction. On the one hand, there is a logical dependence of the degree of satisfaction to the perceived quality. On the other hand, number of studies have also identified a link between students’ satisfaction and their loyalty. This study looks at the determinants of student satisfaction in Georgian Higher Education Institutions. With the objective to detect the main components of service quality influencing students’ satisfaction, the article uses HEdPERF as a measuring instrument of higher education service quality. Data is collected from 793 students of one of the largest universities of the country. An exploratory factor analysis six factors for the further examination. After scale development, a multiple regression analysis is used to test the research hypothesis. The results of the study show that the administrative factors are the most sensitive and have a positive influence on the students’ satisfaction. Also, there is a positive relation between academic programs and student’s satisfaction. The disproportionate attitude is observed between the importance of academic factors and satisfaction.

Revenue Embeddedness and Competing Institutional Logics: How Nonprofit Leaders Connect Earned Revenue to Mission and Organizational Identity

The increasing reliance on earned revenue displayed by nonprofits in the US has raised mission-related organizational identity concerns. However, the effect of a market-driven activity on mission-driven service may vary based on revenue embeddedness: the activity’s connection to the organization’s mission. This study draws on the competing logics of isomorphism and resource dependence to examine how the pursuit of earned revenue affects the organization’s perception of its mission and projection of identity. The authors examine how leaders use language to connect market to mission, presents additional dimensions of embeddedness, and offers propositions for future research.

Properties of the Logical Consequence Operation and Its Relationship with the Independence of Propositional Logic

We study the properties of the logical consequence operation and the characteristic features of independent sets of formulas. Further, we apply these results to propositional logic. Finally, we show under what conditions the results of addition of a formula to independent sets of formulas and the union of two independent sets of formulas are also independent by the operation of logical consequence, i.e., we establish the relationship between the logical consequence and the preservation of independence in propositional logic.

Adaptive business rules framework for workflow management

PurposeChanging scattered and dynamic business rules in business workflow systems has become a growing problem that hinders the use and configuration of workflow-based applications. There is a gap in the existing research studies which currently focus on solutions that are application specific, without accounting for the universal logical dependencies between the business rules and, as a result, do not support adaptation of the business rules in real time. The paper aims to discuss this issue.Design/methodology/approachTo tackle the above problems, this paper adopts a bottom-up approach, which puts forward a component model of the business process workflows and then adds business rules which have clear logical semantics. This allows incremental development of the workflows and semantic indexing of the rules which govern them during the initial acquisition.FindingsThe paper introduces an event-driven model for development of business workflows which is purely logic-based and can be easily implemented using an object-oriented technology, together with a model of the business rules dependencies which supports incremental semantic indexing. It also proposes a two-level inference mechanism as a vehicle for controlling the business process execution and the process of adaptation of the business rules at real time based on propagating the dependencies.Research limitations/implicationsThe framework is strictly logical and completely domain-independent. It allows to account both synchronous and asynchronous triggering events as well as both qualitative and quantitative description of the conditions of the rules. Although our primary interest is to apply the framework to the business processes typical in the construction industry we believe our approach has much wider potential due to its strictly logical formalization and domain independence. In fact it can be used to control any business processes where the execution is governed by rules.Practical implicationsThe framework could be applied to both large business process modelling tasks and small but very dynamic business processes like the typical digital business processes found in online banking or e-Commerce. For example, it can be used for adjusting security policies by adding the capability to adapt automatically the access rights to account for additional resources and new channels of operation which can be very interesting ion both B2C and B2B applications.Social implicationsThe potential scope of the impact of the research reported here is linked to the wide applicability of rule-based systems in business. Our approach makes it possible not only to control the execution of the processes, but also to identify problems in the control policies themselves from the point of view of their logical properties – consistency, redundancies and potential gaps in the logics. In addition to this, our approach not only increases the efficiency, but also provides flexibility for adaptation of the policies in real time and increases the security of the overall control which improves the overall quality of the automation.Originality/valueThe major achievement reported in this paper is the construction of a universal, strictly logic-based event-driven framework for business process modelling and control, which allows purely logical analysis and adaptation of the business rules governing the business workflows through accounting their dependencies. An added value is the support for object-oriented implementation and the incremental indexing which has been possible thanks to the bottom-up approach adopted in the construction of the framework.

Collective entity resolution in multi-relational familial networks

Entity resolution in settings with rich relational structure often introduces complex dependencies between co-references. Exploiting these dependencies is challenging—it requires seamlessly combining statistical, relational, and logical dependencies. One task of particular interest is entity resolution in familial networks. In this setting, multiple partial representations of a family tree are provided, from the perspective of different family members, and the challenge is to reconstruct a family tree from these multiple, noisy, partial views. This reconstruction is crucial for applications such as understanding genetic inheritance, tracking disease contagion, and performing census surveys. Here, we design a model that incorporates statistical signals (such as name similarity), relational information (such as sibling overlap), logical constraints (such as transitivity and bijective matching), and predictions from other algorithms (such as logistic regression and support vector machines), in a collective model. We show how to integrate these features using probabilistic soft logic, a scalable probabilistic programming framework. In experiments on real-world data, our model significantly outperforms state-of-the-art classifiers that use relational features but are incapable of collective reasoning.

From personality disorders to the fact-value distinction

ABSTRACTLouis Charland’s claim that DSM Cluster B personality disorders are moral rather than clinical kinds has recently triggered a lively debate. In order to deliver a reliable report of the latter, both (1) Charland’s arguments concerning the impossibility of identifying and treating personality disorders without applying a morally laden conceptual framework and (2) some critical responses they provoked are discussed. Then, in turn, the conceptual history of the notion of personality disorder is traced, including not only well-recognized contributions from (3) medical psychiatry, psychoanalysis, and DSM nosology, but also (4) an important, but often neglected, tradition of virtue and moral character. Finally, (5) the idea of a normatively neutral concept of personality disorder is scrutinized in the context of its logical dependence on the fact-value distinction. The latter dichotomy’s recent criticism, in particular, is employed to support Charland’s argument and to suggest that the normative character of personality disorders may go much deeper than this or that DSM formulation.

Considerações sobre a operância do psicanalista e a política do ato psicanalítico

Considerando o ato psicanalítico, a autora revisa e avança sua pesquisa sobre o neologismo de Lacan “operância”, produzido na esteira de suas elaborações sobre o ato psicanalítico e a Escola. Nessa ocasião, o acento se coloca no litoral entre o desejo do analista e o ato analítico, ambos na dependência lógica da posição que sustenta a operação da transferência, apontada em 1967 com a expressão porte-à-faux. Um percurso nas elaborações em que Lacan avança sobre o objeto a, articulando a causa do desejo e o mais-de-gozar, aponta que a operância é efeito do paradoxo do ato e põe à prova tanto a direção da cura quanto a sustentação de um trabalho de Escola, em particular no passe.

A periodicity-based parallel time series prediction algorithm in cloud computing environments

In the era of big data, practical applications in various domains continually generate large-scale time-series data. Among them, some data show significant or potential periodicity characteristics, such as meteorological and financial data. It is critical to efficiently identify the potential periodic patterns from massive time-series data and provide accurate predictions. In this paper, a Periodicity-based Parallel Time Series Prediction (PPTSP) algorithm for large-scale time-series data is proposed and implemented in the Apache Spark cloud computing environment. To effectively handle the massive historical datasets, a Time Series Data Compression and Abstraction (TSDCA) algorithm is presented, which can reduce the data scale as well as accurately extracting the characteristics. Based on this, we propose a multi-layer time series periodic pattern recognition (MTSPPR) algorithm using the Fourier Spectrum Analysis (FSA) method. In addition, a Periodicity-based Time Series Prediction (PTSP) algorithm is proposed. Data in the subsequent period are predicted based on all previous period models, in which a time attenuation factor is introduced to control the impact of different periods on the prediction results. Moreover, to improve the performance of the proposed algorithms, we propose a parallel solution on the Apache Spark platform, using the Streaming real-time computing module. To efficiently process the large-scale time-series datasets in distributed computing environments, Distributed Streams (DStreams) and Resilient Distributed Datasets (RDDs) are used to store and calculate these datasets. Logical and data dependencies of RDDs in the P-TSDCA, P-MTSPPR, and P-PTSP processes are considered, and the corresponding parallel execution solutions are conducted. Extensive experimental results show that our PPTSP algorithm has significant advantages compared with other algorithms in terms of prediction accuracy and performance.

Modular Simulation Design of Human-machine Interaction for Civil Aircraft Cockpit

A design method for human-machine interaction (HMI) simulation of the civil aircraft cockpit has been introduced, including model-based design of user interface, logic dependency of control panel and display, and warning conditions under various scenarios. The civil aircraft cockpit HMI simulation can be used for cockpit layout, static and dynamic evaluation of flight tasks, and dynamic assessment platform. Additionally, the modular design has the advantages of flexible modification, cost saving, and quick access to the user’s requirement. Finally, a prototype of high lift system (HLS) of the civil aircraft has been used to illustrate the cockpit HMI simulation with the slat-flap retraction and extraction process.

Axiomatizations of team logics

In a modular approach, we lift Hilbert-style proof systems for propositional, modal and first-order logic to generalized systems for their respective team-based extensions. We obtain sound and complete axiomatizations for the dependence-free fragment FO(∼) of Väänänen's first-order team logic TL, for propositional team logic PTL, quantified propositional team logic QPTL, modal team logic MTL, and for the corresponding logics of dependence, independence, inclusion and exclusion.As a crucial step in the completeness proof, we show that the above logics admit, in a particular sense, a semantics-preserving elimination of modalities and quantifiers from formulas.

Supervenience, Dependence, Disjunction

This paper explores variations on and connections between the topics mentioned in its title, using as something of an anchor the discussion in Valentin Goranko and Antti Kuusisto’s “Logics for propositional determinacy and independence”, a venture into what the authors call the logic of determinacy, which they contrast with (a demodalized version of) Jouko Vaananen’s modal dependence logic. As they make clear in their discussion, these logics are closely connected with the topics of noncontingency and supervenience. Two opening sections of the present paper address some of these connections, including related earlier logical work by the present author as well as very recent work by Jie Fan. The Vaananen-inspired treatment is presented in a third section, and then, in Sections 4 and 5, as a kind of centerpiece for the discussion, we follow Goranko and Kuusisto in elaborating one principal reason offered for preferring their own approach over that treatment, which concerns some anomalies over the behaviour of disjunction in the latter treatment. Sections 6 and 7 look at dependence and (several different versions of) disjunction in inquisitive logic, especially as presented by Ivano Ciardelli. Section 8 revisits the less formal property-supervenience literature with issues from the first two sections of the paper in mind, and we conclude with a Postscript addressing a further conceptual issue pertaining to the relation between modal and quantificational dependence logics.

LOGICS FOR PROPOSITIONAL DETERMINACY AND INDEPENDENCE

AbstractThis paper investigates formal logics for reasoning about determinacy and independence. Propositional Dependence Logic${\cal D}$and Propositional Independence Logic${\cal I}$are recently developed logical systems, based on team semantics, that provide a framework for such reasoning tasks. We introduce two new logics${{\cal L}_D}$and${{\cal L}_{\,I\,}}$, based on Kripke semantics, and propose them as alternatives for${\cal D}$and${\cal I}$, respectively. We analyse the relative expressive powers of these four logics and discuss the way these systems relate to natural language. We argue that${{\cal L}_D}$and${{\cal L}_{\,I\,}}$naturally resolve a range of interpretational problems that arise in${\cal D}$and${\cal I}$. We also obtain sound and complete axiomatizations for${{\cal L}_D}$and${{\cal L}_{\,I\,}}$.

Scaling distributed transaction processing and recovery based on dependency logging

Dependency graph-based concurrency control (DGCC) protocol has been shown to achieve good performance on multi-core in-memory system. DGCCseparates contention resolution from the transaction execution and employs dependency graphs to derive serializable transaction schedules. However, distributed transactions complicate the dependency resolution, and therefore, an effective transaction partitioning strategy is essential to reduce expensive multi-node distributed transactions. During failure recovery, log must be examined from the last checkpoint onward and the affected transactions are re-executed based on the way they are partitioned and executed. Existing approaches treat both transaction management and recovery as two separate problems, even though recovery is dependent on the sequence in which transactions are executed. In this paper, we propose to treat the transaction management and recovery problems as one. We first propose an efficient distributed dependency graph-based concurrency control (DistDGCC) protocol for handling transactions spanning multiple nodes and propose a new novel and efficient logging protocol called dependency logging that also makes use of dependency graphs for efficient logging and recovery. DistDGCCoptimizes the average cost for each distributed transaction by processing transactions in batches. Moreover, it also reduces the effects of thread blocking caused by distributed transactions and consequently improves the runtime performance. Further, dependency logging exploits the same data structure that is used by DistDGCCto reduce the logging overhead, as well as the logical dependency information to improve the recovery parallelism. Extensive experiments are conducted to evaluate the performance of our proposed technique against state-of-the-art techniques. Experimental results show that DistDGCCis efficient and scalable, and dependency logging supports fast recovery with marginal runtime overhead. Hence, the overall system performance is significantly improved as a result.

Improving Control Efficiency of Dynamic Street Lighting by Utilizing the Dual Graph Grammar Concept

The paper introduces a definition of dual graph grammar. It enables two graphs to share information in a synchronized way. A smart city example application, which is an outdoor lighting control system utilizing the dual graph grammar, is also demonstrated. The system controls dimming of street lights which is based on traffic intensity. Each luminaire’s light level is adjusted individually to comply with the lighting norms to ensure safety. Benefits of applying the dual graph grammar are twofold. First, it increases expressive power of the mathematical model that the system uses. It becomes possible to take into account complex geographical distribution of sensors and logical dependencies among them. Second, it increases the system’s efficiency by reducing the problem size during run-time. Experimental results show a reduction of the computation time by a factor of 2.8. The approach has been verified in practice.

The hybridization of national collective bargaining systems: The impact of the economic crisis on the transformation of collective bargaining in the European Union

In this article it is argued that the economic crisis has made national collective bargaining systems increasingly multi-layered, perforated and dynamically unstable, i.e. hybrid. The authors explain these transformations in terms of the concomitance of two different sources of change which do not necessarily follow the same logics. The first source stems from national systems’ endogenous logic of path dependency and the second from pressure to reform in accordance with exogenously applied strategies and logics. It is argued that these sources act like a whipsaw, pushing and pulling national collective bargaining systems between the two logics, leading to hybrid collective bargaining systems.