Synchronization of Deterministic Visibly Push-Down Automata

We generalize the concept of synchronizing words for finite automata, which map all states of the automata to the same state, to deterministic visibly push-down automata. Here, a synchronizing word w does not only map all states to the same state but also fulfills some conditions on the stack content of each run after reading w. We consider three types of these stack constraints: after reading w, the stack (1) is empty in each run, (2) contains the same sequence of stack symbols in each run, or (3) contains an arbitrary sequence which is independent of the other runs. We show that in contrast to general deterministic push-down automata, it is decidable for deterministic visibly push-down automata whether there exists a synchronizing word with each of these stack constraints, more precisely, the problems are in EXPTIME. Under the constraint (1), the problem is even in P. For the sub-classes of deterministic very visibly push-down automata, the problem is in P for all three types of constraints. We further study variants of the synchronization problem where the number of turns in the stack height behavior caused by a synchronizing word is restricted, as well as the problem of synchronizing a variant of a sequential transducer, which shows some visibly behavior, by a word that synchronizes the states and produces the same output on all runs

Perception of Benefits Achieved by IT Management Accounting in the Public Sector

Information technology (IT) is of high relevance in public administrations. Thus, a systematic management and control of its usage is required. IT management accounting is an instrument addressing this issue. However, public IT-managers do not perceive its supposed benefits due to the way in which it is currently implemented. This leads to a low usage of IT management accounting in public administrations. To analyze the gap between its supposed and perceived benefits, we reviewed literature and conducted a case study in a German public administration. Our findings show that - out of the various benefits of IT management accounting according to the literature - public IT-managers only focus on transparency and support for decision-making as benefits. The findings contribute to a better understanding of IT management accounting in public administrations and support practitioners by designing IT management accounting according to the potential benefits for departmental and cross-departmental IT-managers

Understanding the manifold forms of B2B integration - A transaction cost perspective

This paper investigates the characteristics of federal and modular organizations and elicits conclusions on their requirements for IT controlling through a literature review. The literature review showed that different organizational structures create specific conditions concerning IT and IT controlling. Although experience in the regulation and controlling of IT in large and complex organizations has been reorted, the characteristics of these specific organizational conditions and the resulting requirements for the design of an IT controlling concept have not been extensively researched. Creating the missing link between the characteristics of federal and modular organizations and their requirements regarding IT controlling may serve as a foundation for future research and the development of a comprehensive IT controlling concept which encompasses the characteristics and key drivers of this specific organizational for

The standard of living among the poor across Europe: Does employment make a difference?

Employment does not always guarantee sufficient income and a decent standard of living anymore. In this paper, we analyze the relationship between income poverty and material deprivation for employed and unemployed individuals across Europe. To do so, we focus on relevant mechanisms at the individual and institutional levels. We examine how economic, structural and institutional factors shape the relationship between employment, poverty and deprivation. We explore our subject using EU-SILC data from 2015 and cross-national macro-level data from the OECD, Eurostat and UNECE. According to our findings, employment is associated with a higher standard of living even among the poor and when controlling for savings and income level, which may point to the non-monetary benefits of employment. At the macro level, we show that the impact of employment on the living standard of the poor varies according to economic conditions and institutional settings. Our results suggest that policies that promote integration into the labour market without taking into account the quality of jobs and working conditions devalue gainful employment in terms of maintaining a decent standard of living

Synchronizing Deterministic Push-Down Automata Can Be Really Hard

The question if a deterministic finite automaton admits a software reset in the form of a so-called synchronizing word can be answered in polynomial time. In this paper, we extend this algorithmic question to deterministic automata beyond finite automata. We prove that the question of synchronizability becomes undecidable even when looking at deterministic one-counter automata. This is also true for another classical mild extension of regularity, namely that of deterministic one-turn push-down automata. However, when we combine both restrictions, we arrive at scenarios with a PSPACE-complete (and hence decidable) synchronizability problem. Likewise, we arrive at a decidable synchronizability problem for (partially) blind deterministic counter automata. There are several interpretations of what synchronizability should mean for deterministic push-down automata. This is depending on the role of the stack: should it be empty on synchronization, should it be always the same or is it arbitrary? For the automata classes studied in this paper, the complexity or decidability status of the synchronizability problem is mostly independent of this technicality, but we also discuss one class of automata where this makes a difference

The Surprisingly Low Effect of National Culture on E-Government Adoption: A Cross-Cultural Comparison

Governments worldwide are looking for ways to encourage the citizen uptake of online public services. Although some countries are doing better than the others, the vast majority of governments face adoption problems with their electronic services. Other than supply-side barriers, some nations show strong public resistance to government offerings. Drawing on cross-cultural research in IS adoption and diffusion, we posit that differences among adoption behaviors of nations may be attributed to cultural differences. Indeed, national culture shapes the core values and beliefs of individuals, which in turn influence attitudes and behaviors. As being an emerging field of IS, cross-cultural issues in e-government have not received much empirical attention to date. By using nationwide representative samples, we compared two European nations with different cultural profiles and e-government take-up levels. Surprisingly, the results indicate that Germany and Sweden do not differ considerably in their perceptions of enablers and barriers to e-government adoption

A Comprehensive Analysis of E-Government Adoption in the German Household

Much of the prior research on IS adoption recognizes that cultural characteristics of the nations influence their adoption behaviors significantly. In the context of e-government, more empirical research is necessary to understand the adoption behaviors of different nations. Our research focuses on understanding the antecedents of e-government adoption in the German household, which has not been adequately addressed to date. Based on the findings of two representative cross-sectional studies, we derived a comprehensive research model and tested it with 1,000 users in the German household on the specific example of e-filing. While the factors of data protection and security were mentioned as crucial in the descriptive studies, the explanatory analysis with LISREL revealed that compatibility is the main antecedent of e-filing adoption in the German nation, followed by relative advantage and perceived risk. Implications for practice and future research are discussed