Quantifying Nonlinearity Susceptibility via Site-Response Modeling Uncertainty at Three Sites in the Los Angeles Basin

The effects of near-surface soil stratigraphy on the amplitude and frequency content of ground motion are accounted for in most modern U.S. seismic design codes for building structures as a function of the soil conditions prevailing in the area of interest. Nonetheless, currently employed site-classification criteria do not adequately describe the nonlinearity susceptibility of soil formations, which prohibits the development of standardized procedures for the computationally efficient integration of nonlinear ground response analyses in broadband ground-motion simulations. In turn, the lack of a unified methodology for nonlinear site-response analyses affects both the prediction accuracy of site-specific ground-motion intensity measures and the evaluation of site-amplification factors when broadband simulations are used for the development of hybrid attenuation relations. In this article, we introduce a set of criteria for quantification of the nonlinearity susceptibility of soil profiles based on the site conditions and incident ground-motion characteristics, and we implement them to identify the least complex ground response prediction methodology required for the simulation of nonlinear site effects at three sites in the Los Angeles basin. The criteria are developed on the basis of a comprehensive nonlinear site-response modeling uncertainty analysis, which includes both detailed soil profile descriptions and statistical adequacy of ground-motion time histories. Approximate and incremental nonlinear models are implemented, and the limited site-response observations are initially compared to the ensemble site-response estimates. A suite of synthetic ground motions for rupture scenarios of weak, medium, and large magnitude events (M 3.5–7.5) is next generated, parametric studies are conducted for each fixed magnitude scenario by varying the source-to-site distance, and the variability introduced in ground-motion predictions is quantified for each nonlinear site-response methodology. A frequency index is developed to describe the frequency content of incident ground motion relative to the resonant frequencies of the soil profile, and this index is used in conjunction with the rock-outcrop acceleration peak amplitude (PGA_(RO)) to identify the site conditions and ground-motion characteristics where incremental nonlinear analyses should be employed in lieu of approximate methodologies. We show that the proposed intensity-frequency representation of ground motion may be implemented to describe the nonlinearity susceptibility of soil formations in broadband simulations by accounting both for the magnitude-distance-orientation characteristics of seismic motion and the profile stiffness characteristics. The synthetic ground-motion predictions are next used for the development of site-amplification factors for the alternative site-response methodologies, and the results are compared to published site factors of attenuation relations. For the site conditions investigated, currently established amplification factors compare well with synthetic simulations for class C and D site conditions, while long-period amplification factors are overestimated by a factor of 1.5 at the class E site, where site-specific nonlinear analyses should be employed for levels of PGA_(RO)>0.2g

Unbestimmtheitsspielräume - mögliche feministische Anschlüsse an Gilbert Simondons Existenzweise technischer Objekte

Die Dichotomie zwischen dem Geist oder Intellekt als formgebender Entität und dem als 'lebloser' Materie stigmatisierten Körper hat in der ‚westlichen Welt‘ eine lange Tradition, die eine starke (zwei)geschlechtliche Konnotation aufweist. Mit dem Material Turn und Theorien des New Materialism war die Möglichkeit einer feministischen Aufarbeitung der Relation von Materie und weiblichem Körper bzw. weiblicher Subjektivierungsweisen neu gestellt. Gilbert Simondon, der in den letzten Jahren immer intensiver rezipiert wurde, übte in den 1950er-Jahren eine umfassende Kritik des Hylemorphismus, mithilfe dessen ein Körper-Geist-Dualismus sowie eine Höherstellung des formenden Menschen gegenüber der Materie elaboriert wurde. Richtet sich seine Kritik vor allem auf die kulturelle Haltung seiner Zeit gegenüber der Maschine, so versucht dieser Beitrag mögliche Schnittmengen zu feministischen Lesarten von Identität, Geschlecht und Technik zu charakterisieren. Darüber hinaus soll Simondons Theorie des Unbestimmtheitsspielraums und der offenen Maschine als Inspiration für feministische Kritikübung geprüft werden.The dichotomy between the mind or intellect as a formative entity and the body, stigmatized as 'lifeless' matter, has a long tradition in the western world containing a strong (binary) gender connotation. The material turn and theories of new materialism established the possibility of conducting a feminist reappraisal of the relation between matter and the female body. Gilbert Simondon, whose work has been receiving more and more attention in recent years, carried out a comprehensive critique of hylemorphism in the 1950s, elaborating a body–mind dualism as well as the formative elevation of human beings to matter. Although his criticism is directed primarily at contemporary cultural attitudes towards machines, this article attempts to characterize possible intersections between feminist interpretations of identity, gender and technology. Further, it tests his theory of indeterminacy and open machines as an inspiration for feminist criticism

When details are difficult to portray: enriching vision videos

The creation of a shared understanding of the project vision of all relevant stakeholders is vital to the requirements engineering process. One way to create such a shared understanding is through the use of vision videos that visualize the project vision at an early project stage. However, not all functional aspects can be presented. For example, the fact that an access code is valid for only a single use can be hard to visualize. One low-effort solution could be the insertion of short texts or short audio clips. In this work, our question is twofold: What effects do short pieces of additional information have in vision videos? What are suitable ways to add this information to vision videos? To answer these research questions, we investigated three different methods of inserting additional information to vision videos in an eye tracking study. We inserted short texts either below the scene or as overlays and also investigated the addition of short audio clips. These methods were evaluated in terms of participants’ video comprehension, visual effort, cognitive load and subjective preference. The results of our study show that the pieces of additional information improve vision comprehension, thereby supporting the creation of a shared understanding. All investigated methods lead to only marginal increases of the viewers’ cognitive load. Based on our results, we derive recommendations on how to insert additional information in vision videos

Allzubekanntes unvertraut werden lassen

Mit dem von Noam Gramlich und Marie-Luise Angerer herausgegebenen Sammelband „Feministisches Spekulieren“ ist nicht nur eine Sammlung von verschiedenen Perspektiven zur Methode und Diskursgeschichte des Feministischen Spekulierens erschienen. Darin sind auch die Übersetzungen zweier Texte von Ursula K. Le Guin und Anna Lowenhaupt Tsing enthalten, die unlängst zur Bezugsgröße für feministische Theoretiker*innen geworden sind. Neben einer Auslotung der Bedeutungsspielräume von „Spekulation“ werden im Sammelband Begriffe wie Kritik, Narration und Anthropozän auf ihre blinden Flecke hin abgetastet. Ergebnis ist eine vielstimmige Diskussion über die Wirkmacht sowie Wissensgenerierung von Geschichtsschreibung und Narration

Remote Sensing of the Coastal Applications Test Site Test 1: Economic and Accuracy Evaluation of Mapping Techniques

This evaluation of mapping techniques was prepared as part of the Texas Applications System Verification and Transfer (ASVT) project, which is a joint effort of the Texas Natural Resources Information System (TNRIS) Task Force and the National Aeronautics and Space Administration (NASA). The goal of the ASVT project, as described by McCulloch and McKain (1978), is to develop a Texas Natural Resources Inventory and Monitoring System (TNRIMS). The TNRIMS is designed "to assist agencies of the State of Texas in carrying out their statutory responsibilities in the areas of natural resources and the environment" (Finley and Baumgardner, 1981b, p. 2). This study evaluates the use of one component of the TNRIMS, the Remote Sensing Information Subsystem (RSIS), in its developmental state between March and August 1981. The project study area is part of the Coastal Applications Test Site (CATS) (fig. 1), one of five test sites in Texas included in the ASVT project. All test sites were selected to sample the wide variety of land cover/land use categories in the state. The coastal test site was chosen for this evaluation of the RSIS according to (1) state agency needs for information on coastal wetlands, (2) availability of personnel with experience in mapping coastal areas, (3) access to supplementary land cover/land use data, and (4) diversity of land cover/land use types in the area.Bureau of Economic Geolog

Severe Metformin Poisoning Successfully Treated with Simultaneous Venovenous Hemofiltration and Prolonged Intermittent Hemodialysis

Metformin poisoning is a life-threatening condition with a high mortality rate. We present a patient case of metformin poisoning following intake of 80 g metformin resulting in severe lactate acidosis with a nadir pH of 6.73 and circulatory collapse, successfully treated with addition of prolonged intermittent hemodialysis (HD) to continuous venovenous hemofiltration (CVVH). The patient’s pH became normal 48 hours after metformin ingestion during simultaneous CVVH and addition of 22 hours of intermittent HD in the ICU. The highest metformin level was found to be 991 μmol/L (therapeutic range 3.9–23.2 μmol/L). We conclude that in cases of severe metformin poisoning with circulatory shock and extreme lactic acidosis, the usual CVVH modality might not efficiently clear metformin. Therefore, additional prolonged HD should be considered even in the state of cardiovascular collapse with vasopressor requirement