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NOISE MAPPING WITH PSYCHOACOUSTIC ANALYSIS OF SOUND PROPAGATION
No full textSince 1970, soundscapes have been described using psychoacoustic, psychological, sociological data and surveys Psychoacoustics describes human perception of sound via hearing and has been an established approach to assessing product noise for years. Standardized procedures and methods have been available in DIN ISO 12913 since 2014. In part 3 of this standard, psychoacoustic mapping has been explicitly recommended since 2021 to support a representation of actual noise pollution in established noise maps. Currently, there is no software available to create psychoacoustic maps. To assess environmental noise, sound pressure or sound pressure levels measured in decibels (dB) have been used so far. However, it has been proven that sound pressure levels only indicate actual perceived noise pollution to a very limited extent. A non-critical sound pressure level does not necessarily mean that there is no considerable noise pollution. This problem can be addressed by a psychoacoustic view of sound and its propagation. An objective and perceptual evaluation of sound succeeds with psychoacoustic quantities, such as loudness, sharpness, and tonality. A software implementation and the application of psychoacoustic analyses for sound prediction e. g. in maps is the goal of the project presented here. For this purpose, necessary basics of psychoacoustic analyses and the application potential are discussed. Finally, a methodical procedure to create psychoacoustic maps is presented. An application case shows a calculation of a psychoacoustic mapping using measurements of a heat pump as a sound source. The presented and already implemented psychoacoustic mapping for sound prediction serves as a basis for further research and development scopes. Future directions include the implementation of further psychoacoustic analyses, auralization of site-specific sound and the development of holistic annoyance indices from combined, psychoacoustic variables as well as further factors are aimed at
Reference Architecture Models for Smart Service Networks
No full text131136The trend towards smart services but also edge, fog, and cloud services and the countless related developments and technologies have created the demand for frameworks ordering and relating the various approaches into consistent ecosystems. Several initiatives from both industry and academia have been formed, resulting in a significant set of different reference frameworks and architecture models. The developer of smart services needs to understand their strengths and underlying intentions to select the most appropriate for each use case. This chapter explains the most relevant ones for smart services, outlines their focus, and puts them into context
Influence of Powder Properties on the Mixing Behavior of Metal Powders in LPBF
No full textLaser Powder Bed Fusion (LPBF) has become an attractive alternative to conventional processing routes over the past years. While some alloys are already processed in series production, the overall amount of available materials is low. Due to the high price of specially atomized powders, material variation is often neglected. In this work, metal powder blends are created and investigated in order to find the influences of powder properties on blending behaviour. The blending tests are based on 316L and various individually added element powders. This supports the understanding of influences of different parameters on the mixing behaviour. Analytic methods to define properties such as particle diameter, density, particle shape and mixing time are defined. The printing tests serve the verification of the results drawn from the blending processes. A threshold for a homogeneity of a powder blend is defined
Immersive Explainability: Visualizing Robot Navigation Decisions through XAI Semantic Scene Projections in Virtual Reality
No full text16331639End-to-end robot policies achieve high performance through neural networks trained via reinforcement learning (RL). Yet, their black box nature and abstract reasoning pose challenges for human-robot interaction (HRI), because humans may experience difficulty in understanding and predicting the robot's navigation decisions, hindering trust development. We present a virtual reality (VR) interface that visualizes explainable AI (XAI) outputs and the robot's lidar perception to support intuitive interpretation of RL-based navigation behavior. By visually highlighting objects based on their attribution scores, the interface grounds abstract policy explanations in the scene context. This XAI visualization bridges the gap between obscure numerical XAI attribution scores and a human-centric semantic level of explanation. A within-subjects study with 24 participants evaluated the effectiveness of our interface for four visualization conditions combining XAI and lidar. Participants ranked scene objects across navigation scenarios based on their importance to the robot, followed by a questionnaire assessing subjective understanding and predictability. Results show that semantic projection of attributions significantly enhances non-expert users' objective understanding and subjective awareness of robot behavior. In addition, lidar visualization further improves perceived predictability, underscoring the value of integrating XAI and sensor for transparent, trustworthy HRI
A 377-416 GHz Push-Push Frequency Doubler with Driving Stage and Transformer-Based Mode Separation in SiGe BiCMOS
No full text233236This paper presents a WR2.2 push-push frequency doubler with two driving stages using Infineon's advanced 90nm SiGe BiCMOS technology, providing HBTs with an of 300 GHz/500 GHz, respectively. Compared to conventional push-push frequency doublers, we use a design that utilizes transformer-based mode separation. The architecture of the doubler is essentially that of a differential cascode amplifier with a transformer as the load. However, the center tap of the secondary side of the transformer is connected to the MMIC output, causing the second harmonic to be the largest component of the output signal. Measurements exhibit a 3 dB bandwidth of 39 GHz, covering the frequency range from 377 GHz to 416 GHz. The maximum conversion gain is 2.9 dB and the maximum measured output power equals-5.4dBm at 390 GHz
Fast 3D-CFAR for Drone Detection with MIMO Radars
No full text209212In the present paper a novel fast 3D constant false alarm rate (CFAR) detection algorithm is presented and applied to 3D MIMO radar data taking into account azimuth, range and doppler information. The algorithm is designed to minimize the computation effort and its performance is investigated for drone detection in sparse scenarios. For a first experimental drone flight the algorithm significantly improves the detection compared to 2D-CFAR
Linker Modification Enables Control of Key Functional Group Orientation in Macrocycles
No full text2489024923Macrocycles are promising drug modalities that can enable unique ways of conformational preorganization, but how even minor modifications to a macrocyclic scaffold influence the conformational preorganization remains poorly understood. Here, we show how macrocyclization and further derivatization of the linker region can improve affinity, selectivity, and plasma stability in a highly atom-efficient manner. A single, solvent-exposed methyl group was found to improve binding affinity up to 10× over the nonmethylated analog. This led to highly ligand-efficient macrocycles with good brain permeability, improved solubility, and a promising in vivo profile for the FK506-binding protein 51 (FKBP51), a key regulator of the human stress response. Using high-resolution cocrystal structures and molecular dynamics simulations, we found that small linker variations can be tuned to shift the orientation of a key carbonyl group into an advantageous position. This effect is specific to macrocycles, highlighting their potential for fine-tuned adjustments to enable desired properties.682
