Generalized sequential tree-reweighted message passing

This paper addresses the problem of approximate MAP-MRF inference in general graphical models. Following [36], we consider a family of linear programming relaxations of the problem where each relaxation is specified by a set of nested pairs of factors for which the marginalization constraint needs to be enforced. We develop a generalization of the TRW-S algorithm [9] for this problem, where we use a decomposition into junction chains, monotonic w.r.t. some ordering on the nodes. This generalizes the monotonic chains in [9] in a natural way. We also show how to deal with nested factors in an efficient way. Experiments show an improvement over min-sum diffusion, MPLP and subgradient ascent algorithms on a number of computer vision and natural language processing problems

Executive Remuneration in New Zealand and Australia - Do Current Laws, Regulations and Guidelines Ensure "Pay for Performance"?

This article undertakes an examination of the current corporate governance frameworks relating to the remuneration of executives, and particularly executive directors, of listed companies in New Zealand and Australia. The theoretical background of the article builds on agency theory and managerial power theory. On this basis, performance-related remuneration is identified as crucial in aligning the divergent interests of shareholders and executives. Theories also suggest that the board of directors alone is not a sufficient mechanism to ensure that performance-related pay is implemented in practice. Examination of substantive remuneration rules regarding the structure and form of remuneration agreements finds that in both New Zealand and Australia the relevant problems are only sparsely addressed in enforceable law. More emphasis is put on procedural remuneration rules. Particularly in the fields of disclosure and shareholder involvement, Australia is a step ahead of New Zealand.&nbsp

Evolution of Eye Reduction and Loss in Trilobites and Some Related Fossil Arthropods

The fossil record of arthropod compound eyes reflects different modes and occasions of eye reduction and blindness. In the best-studied fossil examples, the trilobites [trilobites: extinct arthropods, dominant during the Palaeozoic], which have an excellent geological record, eyes are primary structures, and in all known genera which lack them, eye-loss is always secondary. Once the eyes were lost, they never were never re-established. The most striking examples occur in the Upper Devonian, when two unrelated major groups of trilobites, with different kinds of eyes, underwent eye reduction and even total loss of the eyes over the same time period, undoubtedly due to long-term environmental change. One reason is that a mud blanket spread over a vast area, there was no firm substrate, and many trilobites became small and many became endobenthic, reducing or losing their eyes in the process. Toxic environmental conditions may also have had an effect. Certain coeval forms remained, however, which still possess perfectly good compound eyes. Either they found vacant refuges where they could survive, or alternatively their visual systems were elaborate enough to adapt to the changing conditions. Another inducement for evolving small, reduced compound eyes is to become a tiny organism oneself, with simply not enough space to establish a regular and functional compound eye, and in such minaturised eyes special adaptations for capturing enough photons are necessary. Thus very small compound eyes often establish wide acceptance angles of their ommatidia, collecting light over large angular ranges of space and it is beneficial to have a wide rhabdom provided that it is short, has a wide lens diameter, and perhaps even possess highly sensitive receptor cells. We find such a miniaturised system in the first recorded planktonic trilobite. Another kind of reduction of a compound eye, or parts of it, also occurs, if selective pressure claims for a high specialisation of eyes that results in several facets fusing into a single functional unit. This probably can be found in phacopid trilobites, ~400 million years old. Here the enlarged aperture of a resulting large lens may allow vision under dim light conditions such as at greater depth. The fossil record gives relatively little evidence about parasites, which often have reduced eyes. Agnostida are blind relatives of trilobites which lived during the Cambrian and Ordovician. An early suggestion was that some of these were parasitic, but this was never commonly adopted. Finally penstastomids (Crustacea), worm-like parasitic organisms, already have been blind from the Cambrian (~487Ma)

Combinatorial Solutions for Shape Optimization in Computer Vision

This thesis aims at solving so-called shape optimization problems, i.e. problems where the shape of some real-world entity is sought, by applying combinatorial algorithms. I present several advances in this field, all of them based on energy minimization. The addressed problems will become more intricate in the course of the thesis, starting from problems that are solved globally, then turning to problems where so far no global solutions are known. The first two chapters treat segmentation problems where the considered grouping criterion is directly derived from the image data. That is, the respective data terms do not involve any parameters to estimate. These problems will be solved globally. The first of these chapters treats the problem of unsupervised image segmentation where apart from the image there is no other user input. Here I will focus on a contour-based method and show how to integrate curvature regularity into a ratio-based optimization framework. The arising optimization problem is reduced to optimizing over the cycles in a product graph. This problem can be solved globally in polynomial, effectively linear time. As a consequence, the method does not depend on initialization and translational invariance is achieved. This is joint work with Daniel Cremers and Simon Masnou. I will then proceed to the integration of shape knowledge into the framework, while keeping translational invariance. This problem is again reduced to cycle-finding in a product graph. Being based on the alignment of shape points, the method actually uses a more sophisticated shape measure than most local approaches and still provides global optima. It readily extends to tracking problems and allows to solve some of them in real-time. I will present an extension to highly deformable shape models which can be included in the global optimization framework. This method simultaneously allows to decompose a shape into a set of deformable parts, based only on the input images. This is joint work with Daniel Cremers. In the second part segmentation is combined with so-called correspondence problems, i.e. the underlying grouping criterion is now based on correspondences that have to be inferred simultaneously. That is, in addition to inferring the shapes of objects, one now also tries to put into correspondence the points in several images. The arising problems become more intricate and are no longer optimized globally. This part is divided into two chapters. The first chapter treats the topic of real-time motion segmentation where objects are identified based on the observations that the respective points in the video will move coherently. Rather than pre-estimating motion, a single energy functional is minimized via alternating optimization. The main novelty lies in the real-time capability, which is achieved by exploiting a fast combinatorial segmentation algorithm. The results are furthermore improved by employing a probabilistic data term. This is joint work with Daniel Cremers. The final chapter presents a method for high resolution motion layer decomposition and was developed in combination with Daniel Cremers and Thomas Pock. Layer decomposition methods support the notion of a scene model, which allows to model occlusion and enforce temporal consistency. The contributions are twofold: from a practical point of view the proposed method allows to recover fine-detailed layer images by minimizing a single energy. This is achieved by integrating a super-resolution method into the layer decomposition framework. From a theoretical viewpoint the proposed method introduces layer-based regularity terms as well as a graph cut-based scheme to solve for the layer domains. The latter is combined with powerful continuous convex optimization techniques into an alternating minimization scheme. Lastly I want to mention that a significant part of this thesis is devoted to the recent trend of exploiting parallel architectures, in particular graphics cards: many combinatorial algorithms are easily parallelized. In Chapter 3 we will see a case where the standard algorithm is hard to parallelize, but easy for the respective problem instances

A Framework for the Classification of Management Control Tools - Experiences with Activity-Based Costing in the German Public Sector

Purpose: To find a suitable framework for the categorisation of management control tools as guidance for a purpose-oriented choice of management control tools. This is done by applying the iron triangle in the case of Activity-based costing (ABC) in the German public sector. Thereby the ABC adoption in the German public sector is analysed, including the discussion of purpose-oriented versus trend-driven management. Methodology: A quantitative empirical study among German municipalities is performed. Thereby the data is collected through a web-based questionnaire. The data analysis is done on basis of univariate methods as well as with a logistic regression analysis. Theoretical perspectives: The idea to develop a framework for the purpose-oriented choice of management control tools is based on the idea of contingency theory. Evidence concerning the use of ABC in Germany supplemented with findings from other contexts serves as a starting point for the empirical work in this thesis. Empirical foundation: Empirical data is gathered through a web-based self-completion questionnaire from high-ranked civil servants in German municipalities. The questionnaire is developed based on relevant literature as well as insights from practice which are gained through two pre-interviews. Conclusions: The iron triangle is not found suitable for the categorisation of ABC in the context of the German public sector as its three dimensions ‘time’, ‘cost’ and ‘quality’ do not cover the emerging area of transparency. Concerning the use of ABC in the German public sector the most important influential factor seems to be the size of the municipality while hype tendencies imply a rather trend-driven adoption

Valuation of online social networks - An economic model and its application using the case of Xing.com

Ubiquitous information technologies like RFID allow for immediate, extensive and fine-grained capture of real world information. Scalable and efficient networks for exchange of this vast amount of information amongst companies are crucial for the economic exploitation of benefits of ubiquitous information technologies. Existing networks bear several limitations like risks of single-point-offailures or bottlenecks, unequally distributed power and burdens as well as inflexibility through stringent structures and formats. In particular there is a need for improving the scalability of solutions and ensuring autonomy of network participants. In this paper we introduce a Peer-to-Peer-based architecture for exchanging distributed information, which are shared among participants of a supply chain facilitated with ubiquitous information technologies. This architecture builds on the wellestablished EPCglobal standards, but can be implemented as an autonomous network. Unlike other architectures it does not need central coordination mechanisms, because it is based on self-organizing Peer-to-Peer protocols. We argue that our architecture supports business processes especially of small and medium-sized enterprises better than other architectures. We provide a discussion about requirements for solutions and a simulation-based analysis of the proposed architecture

A linear framework for region-based image segmentation and inpainting involving curvature penalization

We present the first method to handle curvature regularity in region-based image segmentation and inpainting that is independent of initialization. To this end we start from a new formulation of length-based optimization schemes, based on surface continuation constraints, and discuss the connections to existing schemes. The formulation is based on a \emph{cell complex} and considers basic regions and boundary elements. The corresponding optimization problem is cast as an integer linear program. We then show how the method can be extended to include curvature regularity, again cast as an integer linear program. Here, we are considering pairs of boundary elements to reflect curvature. Moreover, a constraint set is derived to ensure that the boundary variables indeed reflect the boundary of the regions described by the region variables. We show that by solving the linear programming relaxation one gets quite close to the global optimum, and that curvature regularity is indeed much better suited in the presence of long and thin objects compared to standard length regularity

Form, Function and Palaeobiology: preface

Prefacio al número especial de Earth & Environmental Science Transactions of The Royal Society of Edinburgh que compila las presentaciones del simposio ‘‘Form, Function and Palaeobiology’, en el marco del IV Congreso Internacional de Paleontología.Facultad de Ciencias Naturales y Muse

TECHNIQUES FOR ANALYZING NONSTATIONARY VIBRATION DATA

Methods are described and discussed, from a general viewpoint, for analyzing data on non-stationary vibrations. The analysis must take into account both frequency and time as variables, so the methods used are complex and voluminous. The case is also considered in which the vibrations are non- stationary but repetitive. The application of the methods discussed in analysis of missile-vibration problems is outlined. (T.F.H.

Entrepreneurship Promotion at the University Level. Case Study: Feria de las Ideas

RESUMEN: Este trabajo se enfoca en el emprendimiento a nivel universitario, analizando competencias, motivaciones y otros factores internos y externos que influyen sobre la actitud y la actividad emprendedora. Tomando como referencia la metodología del Global Entrepreneurship Monitor (GEM), se realiza un estudio empírico en el que se mide el impacto que la Feria de las Ideas, un evento de emprendimiento organizado en la Universidad de Almería. Para completar el análisis, a partir de del Informe GEM Andalucía 2018/2019, cifras del Instituto Nacional de Estadística, y un relevamiento de las instituciones y programas disponibles para los emprendedores almerienses, se realiza una breve valoración del ecosistema emprendedor de la región. Se hallan, tanto en la Feria de las Ideas como en el contexto regional, aspectos muy alentadores y también algunas limitaciones. Se desprenden de este análisis diferentes líneas de investigación y acción para trabajar, dentro y fuera de la organización del evento analizado. ABSTRACT: This work focuses on entrepreneurship at the university level, analyzing competencies, motivations and other internal and external factors that influence entrepreneurial attitude and activity; also, using the methodology of the Global Entrepreneurship Monitor (GEM) as the main reference, the impact of the Feria de las Ideas, an entrepreneurship event organized at the University of Almería, is measured. To complete the analysis, based on the GEM Andalusia 2018/2019 Report, figures from the Instituto Nacional de Estadística, and the analysis of the institutions and programs available to entrepreneurs, a brief assessment of the entrepreneurial ecosystem in the region is made. Both in the event and in the regional context, several encouraging aspects and also some limitations are found. From this analysis, different lines of investigation and action derive, both to work within and apart from the organization of the event