Johannes Kepler University of Linz

About: Johannes Kepler University of Linz is a education organization based out in Linz, Oberösterreich, Austria. It is known for research contribution in the topics: Thin film & Quantum dot. The organization has 6605 authors who have published 19243 publications receiving 385667 citations.

Headquarters’ Attention and Its Effect on Subsidiary Performance

Abstract: Drawing on a sample of 283 subsidiaries in three countries, we investigate how headquarters’ attention affects subsidiary performance. Scholars have recently argued that top management’s attention is the most critical, scarce and sought-after resource in organizations (Haas and Hansen 2001; Bouquet and Birkinshaw 2008). However, the question how headquarters’ attention affects subsidiary companies remains largely unexplored. Our study shows that subsidiaries which have a high level of strategic choice and receive attention from headquarters perform better than their peers. More specifically, we find that the interactions of subsidiaries’ autonomy, inter-unit power and initiatives with attention increase subsidiary performance.

Design of the Java HotSpot™ client compiler for Java 6

Abstract: Version 6 of Sun Microsystems' Java HotSpot™ VM ships with a redesigned version of the client just-in-time compiler that includes several research results of the last years. The client compiler is at the heart of the VM configuration used by default for interactive desktop applications. For such applications, low startup and pause times are more important than peak performance. This paper outlines the new architecture of the client compiler and shows how it interacts with the VM. It presents the intermediate representation that now uses static single-assignment (SSA) form and the linear scan algorithm for global register allocation. Efficient support for exception handling and deoptimization fulfills the demands that are imposed by the dynamic features of the Java programming language. The evaluation shows that the new client compiler generates better code in less time. The popular SPECjvm98 benchmark suite is executed 45p faster, while the compilation speed is also up to 40p better. This indicates that a carefully selected set of global optimizations can also be integrated in just-in-time compilers that focus on compilation speed and not on peak performance. In addition, the paper presents the impact of several optimizations on execution and compilation speed. As the source code is freely available, the Java HotSpot™ VM and the client compiler are the ideal basis for experiments with new feedback-directed optimizations in a production-level Java just-in-time compiler. The paper outlines research projects that add fast algorithms for escape analysis, automatic object inlining, and array bounds check elimination.

Symmetric Indefinite Preconditioners for Saddle Point Problems with Applications to PDE-Constrained Optimization Problems

Abstract: We consider large scale sparse linear systems in saddle point form. A natural property of such indefinite 2-by-2 block systems is the positivity of the (1,1) block on the kernel of the (2,1) block. Many solution methods, however, require that the positivity of the (1,1) block is satisfied everywhere. To enforce the positivity everywhere, an augmented Lagrangian approach is usually chosen. However, the adjustment of the involved parameters is a critical issue. We will present a different approach that is not based on such an explicit augmentation technique. For the considered class of symmetric and indefinite preconditioners, assumptions are presented that lead to symmetric and positive definite problems with respect to a particular scalar product. Therefore, conjugate gradient acceleration can be used. An important class of applications are optimal control problems. It is typical for such problems that the cost functional contains an extra regularization parameter. For control problems with elliptic state equations and distributed control, a special indefinite preconditioner for the discretized problem is constructed, which leads to convergence rates of the preconditioned conjugate gradient method that are not only independent of the mesh size but also independent of the regularization parameter. Numerical experiments are presented for illustrating the theoretical results.

Image and reputation of family firms: a systematic literature review of the state of research

Abstract: The special characteristics of family firms, such as the owning family’s involvement and control or its strong identification with the business, make creating and preserving a good reputation desirable. Recent studies confirm the positive influence of a firm’s reputation on organizational success and non-financial goals, such as customer retention and social capital. The image and reputation of family firms have been the subject of numerous studies. Despite increasing research intensity, a comprehensive overview of this topic is still lacking. This work provides an inventory of and structure for extant research on the image and reputation of family firms. To this end, a systematic literature analysis has been performed, which includes 73 papers from scientific journals from various business fields. Image and reputation are discussed in different theoretical and geographical contexts. Moreover, this contribution summarizes the ways in which the public perceives family firms and existing influencing factors, courses of action and impacts; in a subsequent step, this work integrates these findings into a model that can serve as starting point for future research activities.

A Three Dimensional Image Cache for Virtual Reality

Abstract: Despite recenl advances in rendering hardware, large and complex virtual environments cannot be displayed with a sufficiently high frame rate, because of limitations in the available rendering performance. This paper presents a new approach of software accelerated rendering which draws from the concepts of impostors, hierarchical scene subdivision and levels of detail. So far software optimization in real-time rendering has merely considered individual objects. This work is actually optimizing the rendering of the whole virtual environment by implementing a three dimensional image cache. It speeds up rendering for large portions of the scene by exploiting the coherence inherent in any smooth frame sequence. The implementation of the three dimensional image cache is discussed and the savings in rendering load achievable on a suitable hardware platform are presented.