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We present an approach to feature extraction that is a generalization of the classical linear discriminant analysis (LDA) on the basis of deep neural networks (DNNs). As for LDA, discriminative features generated from independent Gaussian class conditionals are assumed. This modeling has the advantages that the intrinsic dimensionality of the feature space is bounded by the number of classes and that the optimal discriminant function is linear. Unfortunately, linear transformations are insufficient to extract optimal discriminative features from arbitrarily distributed raw measurements. The generalized discriminant analysis (GerDA) proposed in this paper uses nonlinear transformations that are learnt by DNNs in a semisupervised fashion. We show that the feature extraction based on our approach displays excellent performance on real-world recognition and detection tasks, such as handwritten digit recognition and face detection. In a series of experiments, we evaluate GerDA features with respect to dimensionality reduction, visualization, classification, and detection. Moreover, we show that GerDA DNNs can preprocess truly high-dimensional input data to low-dimensional representations that facilitate accurate predictions even if simple linear predictors or measures of similarity are used.
With the virtual environment developed here, the characteristic
sound radiation patterns of musical instruments can be experienced
in real-time. The user may freely move around a musical instrument, thereby receiving acoustic and visual feedback in real-time. The perception of auditory and visual effects is intensified by the combination of acoustic and visual elements, as well as the option of user interaction. The simulation of characteristic sound radiation patterns is based on interpolating the intensities of a multichannel recording and offers a near-natural mapping of the sound radiation patterns. Additionally, a simple filter has been developed, enabling the qualitative simulation of an instrument’s characteristic sound radiation patterns to be easily implemented within real-time 3D applications. Both methods of simulating sound radiation patterns have been evaluated for a saxophone with respect to their functionality and validity by means of spectral analysis and an auditory experiment.
Design of domestic soundscapes - Evaluation of household appliances in laboratory and reality
(2011)
The effect of inattention and cognitive load on unpleasantness judgments of environmental sounds
(2020)
Increasing global awareness of the benefits of electromobility has brought about the need for new concepts in terms of the acoustic design of future vehicle generations. This includes both the creative design process and the development of suitable methods for the evaluation of target sounds by trial participants. The main difference between e-car sound surveys and those carried out on familiar sound categories is the potential consumer’s lack of experience with electric vehicles. Thus the consumer has no, or very unspecific, expectations in this regard. Several studies have consequently shown that many subjects have to construct their personal frame of reference for evaluation within the listening experiment. However, this is possibly at odds with experience-based expectations relating to the sounds of conventional combustion engines. The result is a conflict of objectives between the traditional and the modern, familiarity and strangeness and not least between driving freedom and ecological awareness. In this context, the authenticity of the sound and the subjective interpretability of the sound information also appear as moderator variables. Moreover, associations with other vehicle categories, for example streetcars, also influence the perceived sound quality. In the course of this contribution, these factors will be expounded and their influence on the evaluation of interior noise discussed.
Test environments in sound quality research often significantly differ from human’s everyday world. Hence the claim for ecological validity of such experiments is reasonable, but too vague in its bare formulation. The estimation of ecological validity requires theoretical knowledge about the meaning and the totality of factors influencing everyday listening and their interaction. Therefore the influence of “reality factors” on the sound evaluation of household appliances was investigated within the framework of nine experiments. These tests were performed in four different settings with varied reality degrees. The psychological realism and the perceived face validity of the tests were examined by means of interviews. The results reveal, on the one hand, that stimuli are perceived as more pleasant in everyday-like environments. The analysis of the relative judgments shows, on the other hand, that the influence of the experimental realism is moderated by a number of factors. These are the saliency and meaning of the sounds, differences between the assessed devices, and personality traits. The correlation and regression analysis confirms that the perceived sound character is widely independent from experimental realism. However, there is great empirical evidence, that valid assessments of sound quality require the reconstruction of everyday attention and action processes.
A visual and spatial feedback system for orientation in virtual sets of virtual TV studios was developed and evaluated. It is based on a green proxy object, which moves around in the acting space by way of four transparent wires. A separate unit controls four winches and is connected to an engine, which renders the virtual set. A new developed plugin registers a virtual object’s position with the proxy object which imitates the virtual object’s movement on stage. This will allow actors to establish important eye contact with a virtual object and feel more comfortable in a virtual set. Furthermore, interaction with the virtual object and its proxy can be realised through a markerless actor tracking system. Several possible scenarios for user application were recorded and presented to experts in the broadcast industry, who evaluated the potential of SpiderFeedback in interviews and by questionnaires.
With the increasing capabilities of machine learning systems and their potential use in safety-critical systems, ensuring high-quality data is becoming increasingly important. In this paper we present a novel approach for the assurance of data quality. For this purpose, the mathematical basics are first discussed and the approach is presented using multiple examples. This results in the detection of data points with potentially harmful properties for the use in safety-critical systems.
The energy topic has become increasingly important in architecture: since buildings are big consumers of energy and architects and the public are interested in energy as never before. [Scognamiglio 2008] The Energy Performance of Building Directive (EPBD) [EU 2010] establishes that starting from 31st December 2020 all new buildings have to be Nearly Zero Energy. The main architectural implication for this condition is that if up until now the domain of design was the building itself, now it is the building and possibly other spaces, that have to be conceived for placing the energy generation devices. Photovoltaics (PV) is particularly suited for reaching the (Nearly) Net ZEB status, due to its technical features, the existing knowledge on how to use PV in buildings, and since it is the easiest and most reliable way to get the (Nearly) Net Zero Energy objectives. [Torcellini 2006] A relevant international effort on the subject of the Net Zero Energy Buildings (Net ZEBs) - Net ZEB meaning that the buildings are connected to an energy infrastructure - is ongoing in the International Energy Agency (IEA), joint Solar Heating and Cooling (SHC) Task 40 and Energy Conservation in Buildings and Community Systems (ECBCS) Annex 52, titled “Towards Net Zero Energy Solar Buildings” [IEA 2008a]. The authors of this paper, all participating in the IEA research group, investigate how the use of PV for Net ZEBs can influence the building’s design, taking into account different building typologies (e. g. new ones vs. existing ones, listed buildings, etc.). Similarities and differences between PV and Solar Thermal (ST) are discussed, too. The paper results in defining some architectural issues for using PV in NZEBs design, which implie to re-think the way buildings are designed.
Interdisciplinary communities involve people and knowledge from different disciplines in addressing a common challenge. Differing perspectives, processes, methods, tools, vocabularies, and standards are problems that arise in this context. We present an approach to support bringing together disciplines based on a common body of knowledge (CBK), in which knowledge from different disciplines is collected, integrated, and structured. The novelty of our approach is twofold: first, it introduces a CBK ontology, which allows one to semantically enrich contents in order to be able to query the CBK in a more elaborate way afterwards. Second, it heavily relies on user participation in building up a CBK, making use of the Semantic MediaWiki as a platform to support collaborative writing. The CBK ontology is backed by a conceptual framework, consisting of concepts to structure the knowledge, to provide access options to it, and to build up a common terminology. To ensure a high quality of the provided contents and to sustain the community’s commitment, we further present organizational means as part of our approach. We demonstrate our work using the example of a Network of Excellence EU project, which aims at bringing together researchers and practitioners from services computing, security and software engineering.
The discipline of engineering secure software and services brings together researchers and practitioners from software, services, and security engineering. This interdisciplinary community is fairly new, it is still not well integrated and is therefore confronted with differing perspectives, processes, methods, tools, vocabularies, and standards. We present a Common Body of Knowledge (CBK) to overcome the aforementioned problems. We capture use cases from research and practice to derive requirements for the CBK. Our CBK collects, integrates, and structures knowledge from the different disciplines based on an ontology that allows one to semantically enrich content to be able to query the CBK. The CBK heavily relies on user participation, making use of the Semantic MediaWiki as a platform to support collaborative writing. The ontology is complemented by a conceptual framework, consisting of concepts to structure the knowledge and to provide access to it, and a means to build a common terminology. We also present organizational factors covering dissemination and quality assurance.
Eye tracking is a measurement technique for determining the orientation and viewing direction of an individual’s eyes. It allows for an evaluation of the individual’s gaze and other related information.There is a wide variety of application areas for eye tracking, however the usage in engineeringindustry is still limited. This paper presents a case study for the use of eye tracking in a testingstation for electrical circuit breakers. The case study aims to evaluate the measurement and analysispossible with the Tobii wearable eye tracking system. From the case study, possibilities, limitationsand considerations for eye tracking in industrial settings are identified and discussed. The paperconcludes that while eye tracking can be used to effectively capture and visualize insightfulinformation, it faces major challenges related to subjectivity in analysis and labour intensiveness.
Information Retrieval and Database Architecture for Conventional Japanese Character Dictionaries
(1997)
The cycle of abstraction-reconstruction which occurs as a fundamental principle in the development of culture and in cognitive processes is described and analyzed. This approach leads to recognition of boundary conditions for and directions of probable development of cognitive tools. It is shown how the transition from a conventional Japanese-English character dictionary to a multi-dimensional language database is an instance of such an abstraction-reconstruction cycle. The different phases of the design of a multi-dimensional language database based upon different computer software technologies are properly placed in this cycle. The methods used include the use of UNIX software tools, classical database methods as-well-as the use of search engines based upon full text search in this process. Several directions of application and extension for a multi-dimensional language database are discussed from the general point of view of an abstraction-reconstruction cycle.
Preserving Software Quality Characteristics from Requirements Analysis to Architectural Design
(2006)
In this paper, we present an approach to adopt UMLsec, which is defined for UML 1.5, to support the current UML version 2.3. The new profile UMLsec4UML2 is technically constructed as a UML profile diagram, which is equipped with a number of integrity conditions expressed using OCL. Consequently, the UMLsec4UML2-profile can be loaded in any Eclipse-based EMF- and MDT-compatible UML editing tool to develop and analyze different kinds of security models. The OCL constraints replace the static checks of the tool support for the old UMLsec defined for UML 1.5. Thus, the UMLsec4UML2-profile not only provides the whole expresiveness of UML2.3 for security modeling, it also brings considerably more freedom in selecting a basic UML editing tool, and it integrates modeling and analyzing security models. Since UML2.3 comprises new diagram types, as well as new model elements and new semantics of diagram types already contained in UML1.5, we consider a number of these changes in detail. More specifically, we consider composite structure and sequence diagrams with respect to modeling security properties according to the original version of UMLsec. The goal is to use UMLsec4UML2 to specify architectural security patterns.
The authors present a security engineering process based on security problem frames and concretized security problem frames. Both kinds of frames constitute patterns for analyzing security problems and associated solution approaches. They are arranged in a pattern system that makes dependencies between them explicit. The authors describe step-by-step how the pattern system can be used to analyze a given security problem and how solution approaches can be found. Afterwards, the security problems and the solution approaches are formally modeled in detail. The formal models serve to prove that the solution approaches are correct solutions to the security problems. Furthermore, the formal models of the solution approaches constitute a formal specification of the software to be developed. Then, the specification is implemented by generic security components and generic security architectures, which constitute architectural patterns. Finally, the generic security components and the generic security architecture that composes them are refined and the result is a secure software product built from existing and/or tailor-made security components.
In this paper, the author aim to present a threat and risk-driven methodology to security requirements engineering. The chosen approach has a strong focus on gathering, modeling, and analyzing the environment in which a secure ICT-system to be built is located. The knowledge about the environment comprises threat and risk models. As presented in the paper, this security-relevant knowledge is used to assess the adequacy of security mechanisms, which are then selected to establish security requirements.
We present a threat and risk-driven methodology to security requirements engineering. Our approach has a strong focus on gathering, modeling, and analyzing the environment in which a secure ICT-system to be built is located. The knowledge about the environment comprises threat and risk models. This security-relevant knowledge is used to assess the adequacy of security mechanisms, which are selected to establish security requirements.
Small and large deformation analysis with the p- and B-spline versions of the Finite Cell Method
(2012)
The article argues that European innovators can profit from some of the concepts of philosophical Daoism, namely "wu-wei" (non-interference) and "ziran" ("go with the flow"). Whereas most Western approaches to innovation emphasize the different stages of the creative process as well as tools to enhance creativity, the Daoist world view allows for the mind to just wander and thus spontaneously discover the solution to a problem in a rather detached state of mind. Creative minds need space for personal development and the permission to wander around without being exposed to control and instant judgement on the results. Training individuals in the tools and techniques of problem solving and creativity as the common approach in innovation management is certainly necessary, but in the end it is the intellectual accomplishment of a creative mind that produces innovation. Managers can allow this to happen when they get the balance of control and non-interference right.
The organic Rankine cycle (ORC) is an established thermodynamic process that converts waste heat to electric energy. Due to the wide range of organic working fluids available the fluid selection adds an additional degree of freedom to the early design phase of an ORC process. Despite thermodynamic aspects such as the temperature level of the heat source, other technical, economic and safety aspects have to be considered. For the fluid selection process in this paper, 22 criteria were identified in six main categories while distinguishing between elimination and tolerance criteria. For an ORC design, the suggested method follows a practical engineering approach and can be used as a structured way to limit the number of interesting working fluids before starting a detailed performance analysis of the most promising candidates. For the first time the selection process is applied to a two-stage reference cycle which uses the waste heat of a large reciprocating engine for cogeneration power plants. It consists of a high temperature and a low temperature cycle in which the condensation heat of the high temperature (HT) cycle provides the heat input of the low temperature (LT) cycle. After the fluid selection process the detailed thermodynamic cycle design is carried out with a thermodynamic design tool that also includes a database for organic working fluids. The investigated ORC cycle shows a net thermal efficiency of about 17,4% in the high temperature cycle with Toluene as the working fluid and 6,2% in low temperature cycle with iso-Butane as the working fluid. The electric efficiency of the cogeneration plant increases from 40,4% to 46,97% with the both stages of the two-stage ORC in operation.
Mixed reality telepresence is becoming an increasingly popular form of interaction in social and collaborative applications. We are interested in how created virtual spaces can be archived, mapped, shared, and reused among different applications. Therefore, we propose a decentralized blockchain-based peer-to-peer model of distribution, with virtual spaces represented as blocks. We demonstrate the integration of our system in a collaborative mixed reality application and discuss the benefits and limitations of our approach.
Live video streaming is becoming increasingly popular as a form of interaction in social applications. One of its main advantages is an ability to immediately create and connect a community of remote users on the spot. In this paper we discuss how this feature can be used for crowdsourced completion of simple visual search tasks (such as finding specific objects in libraries and stores, or navigating around live events) and social interactions through mobile mixed reality telepresence interfaces. We present a prototype application that allows users to create a mixed reality space with a photospherical imagery as a background and interact with other connected users through viewpoint, audio, and video sharing, as well as realtime annotations in mixed reality space. Believing in the novelty of our system, we conducted a short series of interviews with industry professionals on the possible applications of our system. We discuss proposed use-cases for user evaluation, as well as outline future extensions of our system.
Mobile live video streaming is becoming an increasingly popular form of interaction both in social media and remote collaboration scenarios. However, in most cases the streamed video does not take mobile devices' spatial data into account (e.g., the viewers do not know the spatial orientation of a streamer), or use such data only in specific scenarios (e.g., to navigate around a spherical video stream).
We present a system that exploits mobile rotational tracking and photospherical imagery to allow users to share their environment with remotely connected peers “on the go.” We surveyed related interfaces and developed a unique groupware application that shares a mixed reality space with spatially-oriented live video feeds. Users can collaborate through realtime audio, video, and drawings in a virtual space. The developed system was tested in a preliminary user study, which confirmed an increase in spatial and situational awareness among viewers as well as reduction in cognitive workload. Believing that our system provides a novel style of collaboration in mixed reality environments, we discuss future applications and extensions of our prototype.
The organic Rankine cycle (ORC) is an established thermodynamic process that converts waste heat to electric energy. Due to the wide range of organic working fluids available the fluid selection adds an additional degree-of-freedom to the early design phase of an ORC process. Despite thermodynamic aspects such as the temperature level of the heat source, other technical, economic, and safety aspects have to be considered. For the fluid selection process in this paper, 22 criteria were identified in six main categories while distinguishing between elimination (EC) and tolerance criteria (TC). For an ORC design, the suggested method follows a practical engineering approach and can be used as a structured way to limit the number of interesting working fluids before starting a detailed performance analysis of the most promising candidates. For the first time, the selection process is applied to a two-stage reference cycle, which uses the waste heat of a large reciprocating engine for cogeneration power plants. It consists of a high temperature (HT) and a low temperature (LT) cycle in which the condensation heat of the HT cycle provides the heat input of the LT cycle. After the fluid selection process, the detailed thermodynamic cycle design is carried out with a thermodynamic design tool that also includes a database for organic working fluids. The investigated ORC cycle shows a net thermal efficiency of about 17.4% in the HT cycle with toluene as the working fluid and 6.2% in LT cycle with isobutane as the working fluid. The electric efficiency of the cogeneration plant increases from 40.4% to 46.97% with the both stages of the two-stage ORC in operation.
Airborne volcanic ash particles are a known hazard to aviation. Currently, there are no means available to detect ash in flight as the particles are too fine (radii < 30 μm) for on-board radar detection and, even in good visibility, ash clouds are difficult or impossible to detect by eye. The economic cost and societal impact of the April/May 2010 Icelandic eruption of Eyjafjallajökull generated renewed interest in finding ways to identify airborne volcanic ash in order to keep airspace open and avoid aircraft groundings. We have designed and built a bi-spectral, fast-sampling, uncooled infrared camera device (AVOID) to examine its ability to detect volcanic ash from commercial jet aircraft at distances of more than 50 km ahead. Here we report results of an experiment conducted over the Atlantic Ocean, off the coast of France, confirming the ability of the device to detect and quantify volcanic ash in an artificial ash cloud created by dispersal of volcanic ash from a second aircraft. A third aircraft was used to measure the ash in situ using optical particle counters. The cloud was composed of very fine ash (mean radii ~10 μm) collected from Iceland immediately after the Eyjafjallajökull eruption and had a vertical thickness of ~200 m, a width of ~2 km and length of between 2 and 12 km. Concentrations of ~200 μg m(-3) were identified by AVOID at distances from ~20 km to ~70 km. For the first time, airborne remote detection of volcanic ash has been successfully demonstrated from a long-range flight test aircraft.