Showing papers by "Bauhaus University, Weimar published in 2006"
TL;DR: In this paper, the authors investigate the influence of the extent of service employees' display of positive emotions and the authenticity of their emotional labor display on customers' emotional states and subsequently, customers' assessments of the service interaction and their relationship with the service provider.
Abstract: In this study, the authors examine the effects of two facets of employee emotions on customers' assessments of service encounters. Drawing on emotional contagion and emotional labor theories, they investigate the influence of the extent of service employees' display of positive emotions and the authenticity of their emotional labor display on customers' emotional states and, subsequently, on customers' assessments of the service interaction and their relationship with the service provider. To test the study hypotheses, 223 consumers participated in a simulated service encounter in which actors played the roles of service employees. In a 2 × 2 factorial design, the employees varied both the extent of their smiling behavior and their emotional labor display by engaging in surface or deep acting. The results show that the authenticity of employees' emotional labor display directly affects customers' emotional states. However, contrary to expectations, the extent of employee smiling does not influenc...
786 citations
TL;DR: A survey was conducted using a face to face questionnaire with 92 sweet cherry (Prunus avium L.) producers from 10 villages in five districts of the Isparta province where there is intensive sweet cherry production as mentioned in this paper.
269 citations
TL;DR: In this article, the influence of concrete mix parameters on effective elastic properties is studied, and the multigrid method enables efficient computation of very large heterogeneous mesoscale models.
224 citations
10 Apr 2006
TL;DR: It is shown that it is possible to identify potentially plagiarized passages by analyzing a single document with respect to variations in writing style, and new features for the quantification of style aspects are added.
Abstract: Current research in the field of automatic plagiarism detection for text documents focuses on algorithms that compare plagiarized documents against potential original documents. Though these approaches perform well in identifying copied or even modified passages, they assume a closed world: a reference collection must be given against which a plagiarized document can be compared.
This raises the question whether plagiarized passages within a document can be detected automatically if no reference is given, e. g. if the plagiarized passages stem from a book that is not available in digital form. We call this problem class intrinsic plagiarism detection. The paper is devoted to this problem class; it shows that it is possible to identify potentially plagiarized passages by analyzing a single document with respect to variations in writing style.
Our contributions are fourfold: (i) a taxonomy of plagiarism delicts along with detection methods, (ii) new features for the quantification of style aspects, (iii) a publicly available plagiarism corpus for benchmark comparisons, and (iv) promising results in non-trivial plagiarism detection settings: in our experiments we achieved recall values of 85% with a precision of 75% and better.
189 citations
TL;DR: In this article, a methodology for a multi-risk assessment of an urban area is introduced and performed for the city of Cologne, Germany, considering the natural hazards windstorm, flooding and earthquake.
Abstract: In this paper a methodology for a multi-risk assessment of an urban area is introduced and performed for the city of Cologne, Germany, considering the natural hazards windstorm, flooding and earthquake. Moreover, sources of the uncertainty in the analysis and future needs for research are identified. For each peril the following analyses were undertaken: hazard assessment, vulnerability assessment and estimation of losses. To compare the three hazard types on a consistent basis, a common economic assessment of exposed assets was developed. This was used to calculate direct economic losses to buildings and their contents. The perils were compared by risk curves showing the exceedence probability of the estimated losses. In Cologne, most of the losses that occur frequently are due to floods and windstorms. For lower return periods (10–200 years) the risk is dominated by floods. For return periods of more than 200 years the highest damage is caused by earthquakes.
169 citations
TL;DR: In this paper, the sulfate concentration required to form gypsum from portlandite was derived from thermodynamic calculations and experimental measurements, and the obtained results were compared to the sulfates concentrations in laboratory solutions that are commonly used to test the performance of concrete exposed to sulfate attack and also to sulfates that can be expected under field conditions.
152 citations
TL;DR: A model is developed that proposes that differences exist between a primary (short- and long-term theatrical box office) and a sequential (video rental) channel and reveals differences in the impact of success factors across channels.
Abstract: In several product categories, it is typical to release products sequentially to different markets and customer segments Conventional knowledge holds that the roles of various product success drivers do not differ significantly across these sequential channels of distribution The authors examine sequential distribution channels within the motion picture industry and develop a model that proposes that such differences exist between a primary (short- and long-term theatrical box office) and a sequential (video rental) channel The authors test their model with a sample of 331 motion pictures released in theaters and on video during 1999–2001 using partial least squares Results reveal differences in the impact of success factors across channels For example, cultural familiarity enhances box office success but relates negatively to video rental success, and distribution intensity and date of release enhance box office outcomes but have no impact on rental revenues
115 citations
TL;DR: Structural equation modeling demonstrates that studio actions primarily influence early box office results, whereas movie quality influences both short- and long-term theatrical outcomes.
Abstract: We examine the relative roles of marketing actions and product quality in determining commercial success. Using the motion picture context, in which product quality is difficult for consumers to anticipate and information on product success is available for different points in time, we model the effects of studio actions and movie quality on a movie’s sales during different phases of its theatrical run. For a sample of 331 recent motion pictures, structural equation modeling demonstrates that studio actions primarily influence early box office results, whereas movie quality influences both short- and long-term theatrical outcomes. The core results are robust across moderating conditions. We identify two data segments with follow-up latent class regressions and explore the degree of studio actions needed to “save” movies of varying quality. We finally offer some implications for research and management.
97 citations
TL;DR: In this paper, the probability of exceeding a total cost threshold is included in the structure maintenance optimization problem and the probabilities of violating acceptable levels of safety and condition are computed based on this, an optimization task can be formulated and solved in which these probabilities can be included into the formulation of the objective function and the constraint conditions.
77 citations
01 Jan 2006
TL;DR: This work states that an overlap of two documents’ fingerprints indicate a possibly plagiarized text passage, and uses MD5 hashes to construct fingerprints to identify matching passages.
Abstract: Existing methods to text plagiarism analysis mainly base on “chunking”, a process of grouping a text into meaningful units each of which gets encoded by an integer number. Together theses numbers form a document’s signature or fingerprint. An overlap of two documents’ fingerprints indicate a possibly plagiarized text passage. Most approaches use MD5 hashes to construct fingerprints, which is bound up with two problems: (i) it is computationally expensive, (ii) a small chunk size must be chosen to identify matching passages, which additionally increases the effort for fingerprint computation, fingerprint comparison, and fingerprint storage.
72 citations
TL;DR: A novel multifocal projection concept that applies conventional video projectors and camera feedback and is independent of the surfaces' geometry, color and texture, the environment light, as well as of the projectors' position, orientation, luminance, and chrominance.
Abstract: In this paper, we describe a novel multifocal projection concept that applies conventional video projectors and camera feedback. Multiple projectors with differently adjusted focal planes, but overlapping image areas are used. They can be either differently positioned in the environment or can be integrated into a single projection unit. The defocus created on an arbitrary surface is estimated automatically for each projector pixel. If this is known, a final image with minimal defocus can be composed in real-time from individual pixel contributions of all projectors. Our technique is independent of the surfaces' geometry, color and texture, the environment light, as well as of the projectors' position, orientation, luminance, and chrominance.
30 Jul 2006
TL;DR: An innovative algorithm is presented that dynamically adjusts the content of the input images before radiometric compensation is carried out, which reduces the perceived visual artifacts while simultaneously preserving a maximum of luminance and contrast.
Abstract: We present a real-time algorithm for dynamically adjusting radiometric compensation depending on the image content. This reduces the perception of clipping errors by simultaneously preserving a maximum of luminance and contrast. The algorithm is implemented entirely on the GPU and runs in real-time.
TL;DR: In this paper, the authors investigated the change of modal parameters of a gradually damaged prestressed concrete beam and showed that a damage pattern could be identified, which corresponds to the locations of the final failure.
Abstract: In the domain of civil engineering it is often necessary to monitor constructions such as buildings or bridges to maintain safety conditions. Nondestructive test methods outmatch other methods, because they do not influence the constructions performance. One approach is based on the experimental determination of modal parameters (eigenvalues, damping, mode shapes). From the changes in modal data damage can be detected. By updating a reference finite-element model such that its numerical modal data correspond well with the experimental modal data of the damaged structure, the damage pattern can be identified. When applying this technique to prestressed concrete, the problem arises that, because of the prestressing, cracks close again. Therefore a research program was started to investigate the change of modal parameters of a gradually damaged prestressed concrete beam. Static loads with increasing amplitude were applied. In between each load step a dynamic measurement was performed. The results show that the damage detection remains difficult for prestressed concrete in the early damage state. However, a damage pattern could be identified, which corresponds to the locations of the final failure.
TL;DR: Sens-ation is an open and generic service-oriented platform, which provides powerful, yet easy-to-use, tools to software developers who want to develop context-aware, sensor-based infrastructures.
Abstract: Context-aware systems use sensors in order to analyse their environment and to adapt their behaviour. We have designed and developed Sens-ation, an open and generic service-oriented platform, which provides powerful, yet easy-to-use, tools to software developers who want to develop context-aware, sensor-based infrastructures. The service-oriented paradigm of Sens-ation enables standardised communication within individual infrastructures, between infrastructures and their sensors, but also among distributed infrastructures. On a whole, Sens-ation facilitates the development allowing developers to concentrate on the semantics of their infrastructures, and to develop innovative concepts and implementations of context-aware systems.
TL;DR: In this paper, the authors look into nature, form and unique governance issues in debt and equity arrangements in regulated public-private partnership (PPP) organisations and find that debt has not been an effective mechanism to control managers' behaviour since subordinate financing also functions to address debt agency in the capital structure of those regulated PPP organisations.
01 Jan 2006
TL;DR: The role of Informatics in the field - from application integration to ubiquitous user interfaces - is focused on and its concepts and current trends are introduced.
Abstract: The research field Computer-Supported Cooperative Work (CSCW) is concerned with understanding social interaction and the design, development, and evaluation of technical systems supporting social interaction in teams and communities - or in other words it is about researching the use of computer-based technology for supporting collaboration. The field was coined in the 1980th by researchers from computer science, information science and social science. In this paper we will briefly introduce CSCW - its concepts and current trends - and thereby focus on the role of Informatics in the field - from application integration to ubiquitous user interfaces.
25 Mar 2006
TL;DR: A real-time reverse radiosity method for compensating indirect scattering effects that occur with immersive and semi-immersive projection displays that computes a numerical solution directly on the GPU and is implemented with pixel shading and multi-pass rendering which together realizes a Jacobi solver for sparse matrix linear equation systems.
Abstract: We present a real-time reverse radiosity method for compensating indirect scattering effects that occur with immersive and semi-immersive projection displays. It computes a numerical solution directly on the GPU and is implemented with pixel shading and multi-pass rendering which together realizes a Jacobi solver for sparse matrix linear equation systems. Our method is validated and evaluated based on a stereoscopic two-sided wall display. The images appear more brilliant and uniform when compensating the scattering contribution.
TL;DR: In this article, the authors considered complete orthonormal systems of monogenic polynomials together with their hypercomplex derivatives and proved an orthogonal decomposition of the space of square integrable monogenic functions with respect to the derivatives of arbitrary order.
Abstract: The main objective of this article is to consider complete orthonormal systems of monogenic polynomials together with their hypercomplex derivatives. Desired is that the derivatives of the basis polynomials are again basis functions from the original system. Based on this result, we prove an orthogonal decomposition of the space of square integrable monogenic functions with respect to the derivatives of arbitrary order. §Dedicated to Professor Guochun Wen on the occasion of his 75th birthday.
25 Mar 2006
TL;DR: The main purpose of the bent pick ray is to provide continuous visual user feedback, keeping a user informed about the collaborative manipulation of distant objects using a Scaled- Grab technique.
Abstract: This paper presents a collaborative pointing technique for colocated multi-user interaction in projection-based virtual environments. Our approach uses bent pick rays to allow users to collaboratively work together without locking objects. Moreover, a user can manipulate distant objects in immediate reach, using a Scaled- Grab technique. The main purpose of the bent pick ray is to provide continuous visual user feedback, keeping a user informed about the collaborative manipulation.
TL;DR: The need for a specially created PPP Task Force is viewed from an institutional economics perspective as mentioned in this paper, which highlights the impact of Task Forces on the implementation of PPP projects in Germany and features their influence on the procurement process and the achievement of Value for Money.
01 Sep 2006
TL;DR: This work developed a trimming algorithm for the GPU that works with an exact representation of the trimming curves and shows how to realize an iterative ray-object intersection method for NURBS primitives as an intersection program.
Abstract: We propose a conceptual extension of the standard triangle-based graphics pipeline by an additional intersection stage. The corresponding intersection program performs ray-object intersection tests for each fragment of an object's bounding volume. The resulting hit fragments are transfered to the fragment shading stage for computing the illumination and performing further fragment operations. Our approach combines the efficiency of the standard hardware graphics pipeline with the advantages of ray casting such as pixel accurate rendering and exact normals as well as early ray termination. This concept serves as a framework for the implementation of an interactive ray casting system for trimmed NURBS surfaces. We show how to realize an iterative ray-object intersection method for NURBS primitives as an intersection program. Convex hulls are used as tight bounding volumes for the NURBS patches to minimize the number of fragments to be processed. In addition, we developed a trimming algorithm for the GPU that works with an exact representation of the trimming curves. First experiments with our implementation show that real-time rendering of medium complex scenes is possible on current graphics hardware.
TL;DR: In this article, the properties of solutions to Dirac-Hodge and Laplace equations in upper half space endowed with the hyperbolic metric have been studied, and a Borel-Pompeiu formula for C 1 functions and a Green's formula for Hyperbolic harmonic functions have been introduced.
Abstract: We develop basic properties of solutions to the Dirac-Hodge and Laplace equations in upper half space endowed with the hyperbolic metric. Solutions to the Dirac-Hodge equation are called hypermonogenic functions, while solutions to this version of Laplace's equation are called hyperbolic harmonic functions. We introduce a Borel-Pompeiu formula forC
1 functions and a Green's formula for hyperbolic harmonic functions. Using a Cauchy integral formula, we introduce Hardy spaces of solutions to the Dirac-Hodge equation. We also provide new arguments describing the conformal covariance of hypermonogenic functions and invariance of hyperbolic harmonic functions and introduce intertwining operators for the Dirac-Hodge operator and hyperbolic Laplacian.
TL;DR: The prototypic implementation of a Web service is presented, which allows for the analysis and execution of technical models described in the well-known Modelica modeling language and is built on the proposed W3C Web interface stack.
TL;DR: In this paper, a numerical method for Navier-Stokes equations over unbounded domains is developed from the analytic methods used to show existence and uniqueness, which allows to establish a problem-adapted numerical solver based on finite differences.
Abstract: We develop a numerical method for the Navier–Stokes equations over unbounded domains. From the analytic methods used to show existence and uniqueness, we obtain their discrete counterparts which allows us to establish a problem-adapted numerical solver based on finite differences for functions with low regularity.
TL;DR: In this paper, two study areas are investigated, being comparable by the level of seismic hazard and the hazard-consistent scenario events (related to mean return periods of 475, 2475 and 10000 years).
Abstract: Within the framework of recent research projects, basic tools for GIS-based seismic risk assessment technologies were developed and applied to the building stock and regional particularities of German earthquake regions. Two study areas are investigated, being comparable by the level of seismic hazard and the hazard-consistent scenario events (related to mean return periods of 475, 2475 and 10000 years). Significant differences exist with respect to the number of inhabitants, the grade and extent of urbanisation, the quality and quantity of building inventory: the case study of Schmolln in Eastern Thuringia seems to be representative for the majority of smaller towns in Germany, the case study of Cologne (Koln) stands for larger cities. Due to the similarities of hazard and scenario intensities, the considerable differences do not only require proper decisions concerning the appropriate methods and acceptable efforts, they enable conclusions about future research strategies and needs for disaster reduction management. Not least important, results can sharpen the focus of public interest. Seismic risk maps are prepared for different scenario intensities recognising the scatter and uncertainties of site-dependent ground motion and also of the applied vulnerability functions. The paper illustrates the impact of model assumptions and the step-wise refinements of input variables like site conditions, building stock or vulnerability functions on the distribution of expected building damage within the study areas. Furthermore, and in contrast to common research strategies, results support the conclusion that in the case of stronger earthquakes the damage will be of higher concentration within smaller cities like Schmolln due to the site-amplification potential and/or the increased vulnerability of the building stock. The extent of damage will be pronounced by the large number of masonry buildings for which lower vulnerability classes have to be assigned. Due to the effect of deep sedimentary layers and the composition of building types, the urban centre of Cologne will be less affected by an earthquake of comparable intensity.
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TL;DR: This work tries to understand the essential requirements of individual tasks and task combinations to develop corresponding devices and interaction techniques that work better for certain application areas than 2D mouses, gloves, and wands.
Abstract: We provide an overview of some of our input device developments, which we designed in response to the need for more advanced 3D interfaces. Some of our devices are more task-specific and others are more general, but all of them support six or more degrees of freedom (DOF) and work in three dimensions. In our work, we try to understand the essential requirements of individual tasks and task combinations to develop corresponding devices and interaction techniques. This is our way of developing input devices for the 3D domain that work better for certain application areas than 2D mouses, gloves, and wands.
TL;DR: In this article, the authors demonstrate that the fibrous calcium-silicate-hydrates (C-S-H) of tricalciumsilicate (C 3 S) hydration possess a crystalline structure.
Abstract: Using electron diffraction, we demonstrate that the fibrous calcium-silicate-hydrates (C-S-H) of tricalciumsilicate (C 3 S) hydration possess a crystalline structure. The crystalline nature was revealed by limiting the electron dose, which is common in electron microscopy of biomacromolecules. Compared with room temperature, the fading of the electron diffraction patterns at -175°C occurs at an electron dose that is about one order of magnitude higher. A combination of low-dose and cryo-protection methods offers the possibility to investigate the structures of water-containing cement phases by high-resolution electron microscopy in a close-to-native state.
TL;DR: The German Research Network for Natural Disasters (DFNK) as mentioned in this paper is a research network for disaster management in Germany, which aims to develop and provision of the scientific fundamentals for an advanced risk management of important natural disasters in Germany.
Abstract: The German Research Network for Natural Disasters (DFNK) linked 15 partners with scientific expertise in the field of natural hazards. Main objectives were the development and provision of the scientific fundamentals for an advanced risk management of important natural disasters in Germany, i.e., floods, earthquakes, storms and wildland fires. This included risk analyses, the development of information systems for supporting disaster management, and recommendations for risk reduction measures. This paper gives an overview of DFNK and summarises its experiences concerning multidisciplinarity and user-orientation. It illustrates the concept of risk chains, causally linking the different processes from hazard to risk. The step from hazard to risk requires interdisciplinary research teams. The experiences show that integrative concepts allow results not achievable with mono-disciplinary approaches. Integrative approaches pave the way to harmonised safety considerations taking into account the different hazards in a region within a common framework. User-orientation, policy advice and development of operational tools are key issues of disaster research. The experiences of DFNK illustrate the limitations of a research network in bridging the gap between research and application within rather short-term projects. Successful cooperation with users could be established by those activities where, at the beginning of the project, a user was identified who had a strong interest in solving an urgent problem.
25 Mar 2006
TL;DR: First impressions with two application scenarios confirm that sound sources can be quite well located in space by each user, and users appreciated the possibility of natural communication while they were exploring the audio-visual scenarios.
Abstract: We present our experiences of combining wave field synthesis audio with a projection-based multi-viewer stereo display. Wave field synthesis is able to simulate spatial sound sources of various kinds without the need for headphones or user tracking. Multi-viewer systems support multiple tracked users with individual perspectively correct stereoscopic images. The combination of both approaches allows the consistent display of virtual objects and spatial audio sources for multiple participants. First impressions with two application scenarios confirm that sound sources can be quite well located in space by each user. The system allows the creation of sound sources attached to virtual objects, which can be moved around in real-time without perceivable latency. In addition users appreciated the possibility of natural communication while they were exploring the audio-visual scenarios.