Flows on Bidirected Graphs

The study of nowhere-zero flows began with a key observation of Tutte that in planar graphs, nowhere-zero k-flows are dual to k-colourings (in the form of k-tensions). Tutte conjectured that every graph without a cut-edge has a nowhere-zero 5-flow. Seymour proved that every such graph has a nowhere-zero 6-flow. For a graph embedded in an orientable surface of higher genus, flows are not dual to colourings, but to local-tensions. By Seymour's theorem, every graph on an orientable surface without the obvious obstruction has a nowhere-zero 6-local-tension. Bouchet conjectured that the same should hold true on non-orientable surfaces. Equivalently, Bouchet conjectured that every bidirected graph with a nowhere-zero $\mathbb{Z}$-flow has a nowhere-zero 6-flow. Our main result establishes that every such graph has a nowhere-zero 12-flow.Comment: 24 pages, 2 figure

The structural transition of the production system: Regional policy in common understanding

Several scientists, politicians are perceiving a fundamental shift in the structure of the production process and the political regulation-system governing that process. Others claim that there?s nothing worth mentioning about this rage, and posit the continuation of long known cyclical and secular trends. There is a general lack of common understanding and accurate definition in the debate among and between politicians and academics. Neither the concept of ?globalisation? nor that of ?regionalisation? seems to be an accurate ?description? nor an ?explanation? of the structural transformations of the European economy. Yet these vague nominations do have real implications for the perception and situation-definition of the mass and their leaders. Using theoretical tools as the ?Rule of Anticipated Reactions?, ?Hidden Faces of Power?, ?non-decision-making? etc., the proposition is that the ?invisible hands? of market-law and (supra-)state policies have altered the bargaining positions of ?states? and organisations favouring business. The debate about the ?retreat? or ?withering away? of the state, vs. scientists pleading to ?bring the state back in? the analysis, is noticeable in most countries. But the ?objective data? used is unsuitable: they cannot measure accurately the transition under research. The current discussion cannot reveal the importance of the concept of ?structural power? in social relationships: the shifting balance of power between states and markets and between labour and capital. Because of the current division of social sciences, individual disciplines cannot capture thoroughly the transition of the economic system. This transition consists of the shift away from a ?Fordist Regulation? towards ?Something Else?. This transition has farreaching consequences for the neo-corporatist organisation of the ?European? economies and the underlying social differentiation. It is endangering the necessary social cohesion and hindering the supple functioning of the labour market. The classic ?European? Keynesian Welfare State, is undergoing strong incentives, perhaps dictates, towards drastic adjustment. The conditions imposed by mobile capital, both financial and productive, are narrowing the policy-options of national and regional governments: the decrease of difference. At least, this is what is proclaimed in popular discours, in contrast to different findings of scientific research. The modern version of ?beggar-they-neighbour?, the competitive provision of investment-incentives, the involuntarily condescending attitude towards the captains of industry ... are disciplining the labour-force and leading to unemployment and poverty. Because of the delegation of important parts of the socio-economical policy-domains towards the regional government, these too are forced to play the game. Intra-Union and even intra-state social dumping, sometimes for the sake of the European subsidy-policy, are complicating an ?regional understanding?. How can the regions answer this common threat without resulting in a ?mutually assured destruction?? How can they counter these ?structural adjustment plans? without a suitable adequate institutional apparatus on the Union level? What is known in political geography as the ?jumping of scales? is changing the relationship between different policy-levels. The ?regional question? at the turn of the Century is a difficult one: how can the regions defy the obligations of the global production system without rendering a community of regions impossible before it is constructed.

The role of IT/IS in combating fraud in the payment card industry

The vast growth of the payment card industry (PCI) in the last 50 years has placed the industry in the centre of attention, not only because of this growth, but also because of the increase of fraudulent transactions. The conducted research in this domain has produced statistical reports on detection of fraud, and ways of protection. On the other hand, the relevant body of research is quite partial and covers only specific topics. For instance, the provided reports related to losses due to fraudulent usage of cards usually do not present the measures taken to combat fraud nor do they explain the way fraud happens. This can turn out to be confusing and makes one believe that card usage can be more negative than positive. This paper is intended to provide accumulative and organized information of the efforts made to protect businesses from fraud. We try to reveal the effectiveness and efficiency of the current fraud combating techniques and show that organized worldwide efforts are needed to take care of the larger part of the problem. The research questions that will be addressed in the paper are: 1) how can IT/IS help in combating fraud in the PCI?, and 2) is the implemented IT/IS effective and efficient enough to bring progress in combating fraud? Our research methodology is based on a case study conducted in a Macedonian bank. The research is explorative and will be mostly qualitative in nature; however some quantitative aspects will be included. The findings indicate that fraud can take up many forms. A classification of the different forms of data theft into different fraudulent appearances was made. We showed that the benefits from implementing the fraud reduction efforts are multiple. Results show that a bank has to be very small to experience losses from fixed expenditures coming from the implementation of the fraud reduction IT/IS. Medium-sized and large banks should not even see any problems arising from those expenditures. Based on the empirical data and the presented facts we can conclude that the fraud reduction IT/IS do have a positive effect on all sides of the payment process and fulfills the expectations of all stakeholders