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Искусственный интеллект: ответственные инновации перед лицом потенциальных постепенных дисрупций (Artificial Intelligence: Responsible Innovation in the Face of Potential Gradual Disruptions)
Get PDFThis paper deals with the possibility of gradual disruptions at the societal level in the course of rapidly advancing digitalization and spread of AI. The term “disruption” refers to the sudden breakdown of familiar, previously stable constellations. Expectations of stability, assumptions of continuity, and planning security are shattered, casting the prospects for the future in an uncertain light. The Latin roots of the term mean “bursting,” “breaking,” and “tearing,” semantically referring to the temporal structure of more or less sudden, abrupt events. Seen in this light, the talk of gradual disruption in the title of this article seems conceptually contradictory or paradoxical. However, there are many examples of disruption in the world of technology that were heralded by recognizable but often unnoticed signs, particularly by material fatigue and wear. The daily stress on many technical objects, such as V-belts in older vehicles or bridge structures, gradually leads to wear and degradation. In this sense, the notion of grad- ual disruption refers to upheavals with significant or even dramatic damage potential that do not occur unexpectedly and suddenly, like a global pandemic or an earthquake, but build up gradually until they finally lead to the disruption of previously stable constellations. I will argue that this type of potential and gradual disruption could emerge in areas of digitalization and AI. Examples include the increasing but unnoticed standardization of human actions, the silent loss of freedom and individuality, the increasing dependence on the smooth functioning of digital infrastructures, the loss of the future as an open space, or the loss of reflection and learning opportunities due to unlimited acceleration. The possibility of such gradual disruptions poses several challenges to responsible research and innovation (RRI), technology assessment (TA), and ethics. These include epistemological issues (how to detect gradual disruptions at an early stage), ethical issues (how to assess and evaluate concerns relating to the precautionary principle, for example), issues of whether countermeasures should be taken, and issues of communication between irrational exaggeration and irrational trivialization. The final part of the paper will address possible gradual disruptions that can be attributed to both technical parameters and human behavior, and draw conclusions for TA and RRI
Self-Hosting Research Data Infrastructure with Kadi4Mat: A Practical Use Case for Managing Physics Data at IBPT, KIT
Get PDFThis work details the deployment and enhancement of Kadi4Mat, an open-source research data platform at KIT\u27s IBPT, aiming to build a scalable, FAIR-compliant infrastructure for physics researc
Error analysis of tailor-made time integration schemes for certain classes of wave-type equations
Get PDFThis thesis is concerned with the time integration of three classes of wave-type partial differential equations. Each of these equations has numerical challenges, including nonlocal-in-time material laws, nontrivial boundary conditions, and an unbounded spatial domain. We construct tailor-made schemes and provide a rigorous numerical analysis.
We consider the semiclassical magnetic Schrödinger equation on the full space with possibly time-dependent magnetic and electric potentials. For the approximation we use an appropriate Gaussian ansatz function, which leads to a set of ordinary differential equations. We show that in a special case, this ansatz function is the exact solution to the magnetic Schrödinger equation. Furthermore, we provide error bounds with respect to the semiclassical parameter in -norm and we improve the error bound for relevant physical quantities of interest.
The second setting is concerned with a scattering problem for Maxwell\u27s equations on an unbounded domain. The scatterer consists of a nonlocal-in-time material, which is modeled as a convolution in Maxwell\u27s equations. In this situation, we use a coupling on the scatterer\u27s bounded interface and derive a boundary integral equation.
For the discretization we employ a convolution quadrature combined with a boundary element method. Finally, we show that this numerical approach is stable and we prove convergence rates.
For a semilinear viscoacoustic wave equation with a retarded material law and kinetic boundary conditions, we construct and analyze an implicit-explicit (IMEX) scheme. The IMEX scheme is computationally efficient, since it avoids the solution of nonlinear systems. The material law is described by a convolution term with exponential kernels. After applying an appropriate shift, we couple the convolution term as an auxiliary variable to the first-order system of partial differential equations. For the kinetic boundary conditions we make use of suitable bulk-surface Sobolev spaces to show wellposedness
An electro-optical bunch profile monitor for FCC-ee
Get PDFThe Future Circular Lepton Collider (FCC-ee) presents challenges for a longitudinal bunch profile monitor due to its wide range of bunch lengths and charge densities across its four distinct operational modes. For commissioning, monitoring the top-up injection, and energy calibration, the FCC-ee requires non-destructive, single-shot measurements of the bunch length and profile. This contribution proposes an in-vacuum electro-optical (EO) longitudinal bunch profile monitor for single-shot measurements at high repetition rates, building on the successful EO monitor at the Karlsruhe Research Accelerator (KARA) at the Karlsruhe Institute of Technology. A novel single-pass conceptual design for the in-vacuum holder of the electro-optical crystal is presented, utilizing prisms instead of a mirror to guide the laser through the crystal, which additionally allows measurements of the long bunches foreseen for FCC-ee operation mode at the Z-pole energy. A first prototype has been constructed and tested at the in-air test stand of the CERN Linear Electron Accelerator for Research (CLEAR). Results from the prototype tests are presented, demonstrating the proof of principle for the single-pass prism-based EO monitor design for FCC-ee
Tuning membraneless microbial electrolysis cells operation alters efficiency and anodic microbiome toward scalable hydrogen production from sludge-hydrolysate
Get PDFThe practical implementation of microbial electrolysis cells (MECs) is hindered by challenges in optimizing system performance with complex substrates. This study addresses that gap by evaluating MECs fed with hydrolysate, an appealing substrate rich in organic-acids. Through systematic variation of substrate concentration (20–60 %), pH (5–8), and applied anodic potential (−0.2 to +0.4 V vs standard hydrogen electrode [SHE]), the optimal operational conditions were defined as 40 %-hydrolysate, pH 8, and +0.4 V vs SHE, yielding a mean current density of 3.4 A/m and coulombic efficiencies (CE) of 38 % and 96 % based on total organic carbon (TOC) and total volatile fatty acids (VFAs), respectively. Scalability was demonstrated using a 10 L rotating disk bioelectrochemical reactor (RDBER) at 0 and 0.4 V vs SHE, achieving a maximum hydrogen production rate of 30.57 L/m2/d and minimal methane formation at 0.4 V. These findings offer a framework for optimizing MECs under real-feedstock conditions
Distorting the top resonance with effective interactions
Get PDFInterference effects in effective field theory (EFT) analyses can significantly distort sensitivity expectations, leaving subtle yet distinct signatures in the reconstruction of final states crucial for limit setting around Standard Model predictions. Using the specific example of four-fermion operators in top-quark pair production at the Large Hadron Collider (LHC), we provide a detailed quantitative assessment of these resonance distortions. We explore how continuum four-fermion interactions affect the resonance shapes, creating potential tensions between the high-statistics resonance regions and rare, high momentum-transfer continuum excesses. Our findings indicate that, although four-fermion interactions do modify the on-shell region comparably to continuum enhancements, current experimental strategies at the high-luminosity LHC are unlikely to capture these subtle interference-induced distortions. Nonetheless, such effects could become critical for precision analyses at future lepton colliders, such as the FCC-ee. Our work underscores the importance of resonance-shape measurements as complementary probes in global EFT approaches, guiding robust and self-consistent experimental strategies in ongoing and future high-energy physics programs
Simulating and Evaluating Search Strategies for Highly Accurate Localization Based on Wireless Technologies Using Autonomous Unmanned Aerial Vehicles
Get PDFWhen persons are reported missing, the authorities are under severe time pressure to localize and safeguard them. This is especially the case, if the missing persons\u27 lives might be threatened, e.g. if the night approaches and the outside temperatures are endangering survival over night. However, the localization of the missing persons can be quite challenging in many scenarios such as rough terrain where ground units of the authorities have limited access.
In this paper, we therefore present a new approach with four different strategies for automated Search-And-Rescue (SAR) missions, i.e. the localization of missing persons\u27 mobile devices using unmanned aerial vehicles. The strategies are compatible with multiple wireless technologies, e.g. cellular networks or WiFi. They are then evaluated with extensive simulations to cover a wide range of possible scenarios, including different search area shapes and sizes, missing persons\u27 velocities, and equipment characteristics. The evaluation focuses on the required time to localize the device, the success rate of the SAR mission, and the running costs of the mission. Our results show that the missing person can be found quickly, within 20 to 30 minutes in most scenarios. For slow-moving persons, the time of localization could even be significantly reduced.
Finally, we provide an overview of the advantages and disadvantages of each strategy. This allows to select the best one for a given scenario
A-priori estimation of axial dispersion and residence time distribution in laminar flow through helically coiled tubes
Get PDFParticle Size Matters – Impact of Particle Size and Crucible Geometry on Sublimation Behavior of Formamidinium Iodide
No full textVapor phase deposition processes for the fabrication of perovskite solar cells show great potential for transferring from laboratory-scale to continuous industrial-scale production. Precise process control and high process reproducibility are of utmost importance to unlock their full potential. In this regard, the sublimation behavior and rate control of organic precursor materials in thermal evaporation processes are particularly challenging. Here, we investigate in detail how the particle size of formamidinium iodide (FAI) and the crucible geometry influence the directionality of the emitted vapor flux. We show that conical crucibles lead to beam focusing of the vapor flux, while cylindrical crucibles show a broader, less directional emission profile. This leads to differences in the homogeneity of material deposition depending on the lateral source-to-substrate distance. Furthermore, there is a substantial impact of FAI particle size on the directionality of the vapor flux for conical crucibles, affecting the deposited material thickness gradient over the substrate. Analyzing commonly employed inorganic materials reveals the strong material dependence of effusion characteristics, leading to additional complexity for multi-material deposition processes. Our findings emphasize that both homogenization of organic precursor materials and optimization of source geometry and arrangement are critical for achieving uniform deposition and, consequently, improved process reproducibility