Clustering algorithm based on minimal path loss ratio for vehicular communication

Emerging vehicular comfort applications pose a host of completely new set of requirements such as maintaining end-to-end connectivity, packet routing, and reliable communication for internet access while on the move. One of the biggest challenges is to provide good quality of service (QoS) such as low packet delay while coping with the fast topological changes. In this paper, we propose a clustering algorithm based on minimal path loss ratio (MPLR) which should help in spectrum efficiency and reduce data congestion in the network. The vehicular nodes which experience minimal path loss are selected as the cluster heads. The performance of the MPLR clustering algorithm is calculated by rate of change of cluster heads, average number of clusters and average cluster size. Vehicular traffic models derived from the Traffic Wales data are fed as input to the motorway simulator. A mathematical analysis for the rate of change of cluster head is derived which validates the MPLR algorithm and is compared with the simulated results. The mathematical and simulated results are in good agreement indicating the stability of the algorithm and the accuracy of the simulator. The MPLR system is also compared with V2R system with MPLR system performing better. © 2013 IEEE.

Clustering algorithm based on minimal path loss ratio for vehicular communication

Emerging vehicular comfort applications pose a host of completely new set of requirements such as maintaining end-to-end connectivity, packet routing, and reliable communication for internet access while on the move. One of the biggest challenges is to provide good quality of service (QoS) such as low packet delay while coping with the fast topological changes. In this paper, we propose a clustering algorithm based on minimal path loss ratio (MPLR) which should help in spectrum efficiency and reduce data congestion in the network. The vehicular nodes which experience minimal path loss are selected as the cluster heads. The performance of the MPLR clustering algorithm is calculated by rate of change of cluster heads, average number of clusters and average cluster size. Vehicular traffic models derived from the Traffic Wales data are fed as input to the motorway simulator. A mathematical analysis for the rate of change of cluster head is derived which validates the MPLR algorithm and is compared with the simulated results. The mathematical and simulated results are in good agreement indicating the stability of the algorithm and the accuracy of the simulator. The MPLR system is also compared with V2R system with MPLR system performing better. © 2013 IEEE.

Short fatigue crack path determinants in polycrystalline Ni-base superalloys

Fifty seven short fatigue cracks in the Ni-base superalloy AP1 have been examined, to ascertain how the paths taken by growing fatigue cracks are determined. The observations were made on the surface of a smooth specimen, and on the exposed fracture surfaces. Three dimensional reconstructions of the vulnerable microstructures in the vicinity of the cracks were produced. Initiation occurred in mode II, with the lines of intersection of the initiation sites with the specimen top surface orientated at approximately 45° to the tensile axis. These initiation sites developed in slip bands which crossed a large grain and at least one other grain via a grain boundary with a low angle of misorientation. 'River markings' on one of the initiation facets, indicated that the crack first opened from the top centre of the initiation grain. Subsequent to initiation, the growth paths of these cracks are related to the misorientations of the grains and the progress of the crack front.

Quantum Mechanics of Guiding Center Motion in Strong Magnetic Field (Coherent State Path Integral Approach)

A new approach is proposed for the quantum mechanics of guiding center motion in strong magnetic field. This is achieved by use of the coherent state path integral for the coupled systems of the cyclotron and the guiding center motion. We are specifically concerned with the effective action for the guiding center degree, which can be used to get the Bohr- Sommerfeld quantization scheme. The quantization rule is similar to the one for the vortex motion as a dynamics of point particles.

Transition and foreign aid policies in the Visegrád countries:a path dependant approach

The paper argues that the current emerging international development policies of the Visegrád (V4) countries are heavily influenced by the certain aspects of the Communist past and the transition process. Due to these influences, the V4 countries have difficulties in adapting the foreign aid practices of Western donors and this leads to the emergence of a unique Central and Eastern European development cooperation model. As an analytical background, the paper builds on the path dependency theory of transition. A certain degree of path dependence is clearly visible in V4 foreign aid policies, and the paper analyses some aspects of this phenomenon: how these new emerging foreign aid donors select their partner countries, how much they spend on aid, how they formulate their aid delivery policies and institutions and what role the non-state actors play. The main conclusions of the paper are that the legacies of the Communist past have a clear influence and the V4 countries still have a long way to go in adapting their aid policies to international requirements.

An Optimal Distributed Algorithm for All-Pairs Shortest-Path

In this paper the network problem of determining all-pairs shortest-path is examined. A distributed algorithm which runs in O(n) time on a network of n nodes is presented. The number of messages of the algorithm is O(e+n log n) where e is the number of communication links of the network. We prove that this algorithm is time optimal.

An efficient, approximate path-following algorithm for elastic net based nonlinear spike enhancement

Unwanted spike noise in a digital signal is a common problem in digital filtering. However, sometimes the spikes are wanted and other, superimposed, signals are unwanted, and linear, time invariant (LTI) filtering is ineffective because the spikes are wideband - overlapping with independent noise in the frequency domain. So, no LTI filter can separate them, necessitating nonlinear filtering. However, there are applications in which the noise includes drift or smooth signals for which LTI filters are ideal. We describe a nonlinear filter formulated as the solution to an elastic net regularization problem, which attenuates band-limited signals and independent noise, while enhancing superimposed spikes. Making use of known analytic solutions a novel, approximate path-following algorithm is given that provides a good, filtered output with reduced computational effort by comparison to standard convex optimization methods. Accurate performance is shown on real, noisy electrophysiological recordings of neural spikes.

Nonlinear signal transformations:path to capacity above the linear AWGN Shannon limit

We present a methodology for simultaneous optimization of modulation format and regenerative transformations in nonlinear communication channels. We derived analytically the maximum regenerative Shannon capacity, towards which any regenerative channel tends at high SNR and large number of regenerators.

Market reform and state paternalism in Hungary: a path-dependent approach

Hungary is one of the worst-hit countries of the current financial crisis in Central and Eastern Europe. The deteriorating economic performance of the country is, however, not a recent phenomenon. A relatively high ratio of redistribution, a high and persistent public deficit and accelerated indebtedness characterised the country not just in the last couple of years but also well before the transformation, which also continued in the postsocialist years. The gradualist success of the country – which dates back to at least 1968 – in the field of liberalisation, marketisation and privatisation was accompanied by a constant overspending in the general government. The paper attempts to explore the reasons behind policymakers’ impotence to reform public finances. By providing a path-dependent explanation, it argues that both communist and postcommunist governments used the general budget as a buffer to compensate losers of economic reforms, especially microeconomic restructuring. The ever-widening circle of net benefiters of welfare provisions paid from the general budget, however, has made it simply unrealistic to implement sizeable fiscal adjustment, putting the country onto a deteriorating path of economic development.

Market reform and fiscal laxity in Communist and post-Communist Hungary: A path-dependent approach

Purpose – The purpose of this paper is to present a conceptual framework in order to analyse and understand the twin developments of successful microeconomic reform on the one hand and failed macroeconomic stabilisation attempts on the other hand in Hungary. The case study also attempts to explore the reasons why Hungarian policymakers were willing to initiate reforms in the micro sphere, but were reluctant to initiate major changes in public finances both before and after the regime change of 1989/1990. Design/methodology/approach – The paper applies a path-dependent approach by carefully analysing Hungary's Communist and post-Communist economic development. The study restricts itself to a positive analysis but normative statements can also be drawn accordingly. Findings – The study demonstrates that the recent deteriorating economic performance of Hungary is not a recent phenomenon. By providing a path-dependent explanation, it argues that both Communist and post-Communist governments used the general budget as a buffer to compensate the losers of economic reforms, especially microeconomic restructuring. The gradualist success of the country – which dates back to at least 1968 – in the field of liberalisation, marketisation and privatisation was accompanied by a constant overspending in the general government. Practical implications – Hungary has been one of the worst-hit countries of the 2008/2009 financial crisis, not just in Central and Eastern Europe but in the whole world. The capacity and opportunity for strengthening international investors' confidence is, however, not without doubts. The current deterioration is deeply rooted in failed past macroeconomic management. The dissolution of fiscal laxity and state paternalism in a broader context requires, therefore, an all-encompassing reform of the general government, which may trigger serious challenges to the political regime as well. Originality/value – The study aims to show that a relatively high ratio of redistribution, a high and persistent public deficit and an accelerated indebtedness are not recent phenomena in Hungary. In fact, these trends characterised the country well before the transformation of 1989/1990, and have continued in the post-socialist years, too. To explain such a phenomenon, the study argues that in the last couple of decades the hardening of the budget constraint of firms have come at the cost of maintaining the soft budget constraint of the state.

Transition and Foreign Aid Policies in the Visegrád Countries: A Path Dependant Approach

The paper argues that the current emerging international development policies of the Visegrád (V4) countries are heavily influenced by the certain aspects of the communist past and the transition process. Due to these influences, the V4 countries have difficulties in adapting the foreign aid practices of Western donors and this leads to the emergence of a unique Central and Eastern European development cooperation model. As an analytical background, the paper builds on the path dependency theory of transition. A certain degree of path dependence is clearly visible in V4 foreign aid policies, and the paper analyzes some aspects of this phenomenon: how these new emerging foreign aid donors select their partner countries, how much they spend on aid, how they formulate their aid delivery policies and institutions and what role the non state actors play. The main conclusions of the paper are that the legacies of the communist past have a clear influence and the V4 countries still have a long way to go in adapting their aid policies to international requirements.

The Shapley value for shortest path games

In this paper shortest path games are considered. The transportation of a good in a network has costs and benet too. The problem is to divide the prot of the transportation among the players. Fragnelli et al (2000) introduce the class of shortest path games, which coincides with the class of monotone games. They also give a characterization of the Shapley value on this class of games. In this paper we consider further four characterizations of the Shapley value (Shapley (1953)'s, Young (1985)'s, Chun (1989)'s, and van den Brink (2001)'s axiomatizations), and conclude that all the mentioned axiomatizations are valid for shortest path games. Fragnelli et al (2000)'s axioms are based on the graph behind the problem, in this paper we do not consider graph specic axioms, we take TU axioms only, that is, we consider all shortest path problems and we take the view of abstract decision maker who focuses rather on the abstract problem than on the concrete situations.

The Shapley value for shortest path games

In this paper shortest path games are considered. The transportation of a good in a network has costs and benet too. The problem is to divide the prot of the transportation among the players. Fragnelli et al (2000) introduce the class of shortest path games, which coincides with the class of monotone games. They also give a characterization of the Shapley value on this class of games. In this paper we consider further four characterizations of the Shapley value (Shapley (1953)'s, Young (1985)'s, Chun (1989)'s, and van den Brink (2001)'s axiomatizations), and conclude that all the mentioned axiomatizations are valid for shortest path games. Fragnelli et al (2000)'s axioms are based on the graph behind the problem, in this paper we do not consider graph specic axioms, we take TU axioms only, that is, we consider all shortest path problems and we take the view of abstract decision maker who focuses rather on the abstract problem than on the concrete situations.

The recruitment process of the Shining Path and MRTA guerrilla groups: A political psychological perspective

This thesis is an analysis of the recruitment process of the Shining Path -SP- and Revolutionary Movement “Túpac Amaru” -MRTA- guerrilla groups. Although SP was considered more aggressive, it gained more followers than MRTA. This thesis tries to explain why. Social Revolution Theory and Social Movement Theory provide explanations based on issues of “poverty”, disregarding the specific characteristics of the guerrilla groups and their supporters, as well as the influence of specific persuasive processes between the leaders of the groups and their followers. Integrative complexity theory, on the contrary, provides a consistent method to analyze cognitive processes: because people tend to reject complex and sophisticated explanations that require mental efforts, simplicity was the key for success. To prove which guerrilla group provided a simpler worldview, a sample of official documents of SP and MRTA are compared. Finally, content analysis is applied through the Paragraph Completion Test (P.C.T.). ^