28 research outputs found
Autoencoders for per-lumisection data quality monitoring at CMS
No full textThe monitoring of data quality is crucial both online, during the data taking, to promptly spot issues and act on them, and offline, to provide analysts with datasets that are cleaned against the occasional failures that may have crept in. Typically, data quality monitoring (DQM) is performed by \textit{shifters} who look at a set of integrated quantities, compare them with reference histograms, and, based on their experience and training, assign quality flags. Recently CMS has developed the possibility of producing DQM plots per-lumisection, where a lumisection is a time unit corresponding to about 23 s of data taking. To analyze per-lumisection data, a manual approach would be prohibitive due to the high number of lumisections, therefore an automated one would be preferable. In this work, the first use in CMS of AutoEncoders to perform anomaly detection on per-lumisection data, specifically for quantities associated with jets and missing transverse energy, is presented. The technique developed allows the detection of anomalies at the level of individual lumisections, which might be overlooked when examining integrated quantities, and serves as a proof of concept regarding the efficacy of this and similar approaches
Domain adaptation and active learning AI techniques in the context of regression, simulation and agnostic optimization of large industrial apparatuses and high energy physics experiments
No full textAutoencoders for per-lumi-section data quality monitoring of the CMS detector
No full textThe monitoring of data quality is crucial both online, during the data taking, to promptly spot issues and act on them, and offline, to provide analysts with datasets that are cleaned against the occasional failures that may have crept in. Typically, data quality monitoring (DQM) is performed by shifters who look at a set of integrated quantities, compare them with reference histograms, and, based on their experience and training, assign quality flags. Recently CMS has developed the possibility of producing DQM plots per-lumisection, where a lumisection is a time unit corresponding to about 23 s of data taking. To analyze per-lumisection data, a manual approach would be prohibitive due to the high number of lumisections, therefore an automated one would be preferable. In this work, the first use in CMS of AutoEncoders to perform anomaly detection on per-lumisection data, specifically for quantities associated with jets and missing transverse energy, is presented. The technique developed allows the detection of anomalies at the level of individual lumisections, which might be overlooked when examining integrated quantities, and serves as a proof of concept regarding the efficacy of this and similar approaches
Bestimmung und Verortung des Demand-Side-Integration-Potenzials von Nichtwohngebäuden des tertiären Sektors unter Verwendung amtlicher Liegenschaftskatasterinformationssysteme (ALKIS)
No full textZusammenfassung
Vor dem Hintergrund des beständig ansteigenden Anteils der Stromerzeugung aus Windkraft- und PV Anlagen wird die Nutzung von Lastverlagerungsoptionen auf der Verbraucherseite (Demand Side Integration (DSI)) immer bedeutender. DSI vermag u. a. einen wichtigen Beitrag zur Glättung der aus der schwankenden Einspeisung erwachsenden Fluktuationen zu leisten und hat darüber hinaus einen kostenreduzierenden Effekt bei Ausbau und Anpassung der Übertragungs- und Verteilnetze im Rahmen der Energiewende.
Die vorliegende Arbeit befasst sich daher mit der Entwicklung einer Methode, das theoretische DSI Potenzial aus Lüftungs- und Kälteanlagen (LuK) in Nichtwohngebäuden des tertiären Sektors mit Hilfe amtlicher Liegenschaftskatasterinformationssysteme (ALKIS) zu bestimmen und zu verorten. ALKIS bildet ein bundeseinheitlich verwendetes Datenmodell die topografisch-kartografischen Daten kombiniert mit den digitalisierten Liegenschaftsverzeichnissen der Städte. Das ALKIS für Hamburg enthält Daten zu den ca. 370.000 Gebäuden der Stadt, mit Informationen über Lage, Größe (Grundfläche und Anzahl Geschosse) sowie zur Gebäudenutzung. Aus dieser Grundgesamtheit wurden 7.389 Gebäude aus 17 Nutzungsgruppen bestimmt, deren Nutzung büroähnlichen Charakter hat. Insgesamt entspricht die selektierte Gebäudegruppe etwa 27% aller beheizten Nichtwohngebäude der Stadt Hamburg (und etwa 0,5% der Nichtwohngebäude Deutschlands).
Die Nutzung und Verarbeitung der Informationen des ALKIS zur DSI Potenzialanalyse erfolgt im Rahmen einer Voranalyse unter Verwendung von pauschalierten Flächenzerlegungen der Gebäude basierend auf der jeweiligen Nutzungsart und auf Kennwerten zu konditionierten Flächenanteilen sowie Kennwerten zu den installierten Leistungen für die Gebäudekonditionierung mit LuK. Dabei werden auf Basis unterschiedlicher Kennwertkombinationen drei Bedarfsklassen definiert („Niedrig“, „Mittel“ und „Hoch“). Für jedes Gebäude wird die für jede der drei Bedarfsklassen zu erwartende elektrische Leistung getrennt nach Lüftungsanalgen und Klimaanlagen bestimmt. Zuvor werden in einer ABC Analyse die Gebäude herausgefiltert, für die das Vorhandensein von LuK unwahrscheinlich ist. Da die entwickelte Methode eine Voranalyse darstellt, also ohne Begehung der Gebäude und ohne Kenntnis der Energieverbrauchdaten auskommt, erfolgte eine Validierung des methodischen Vorgehens anhand realer Daten. Dazu wurden die theoretischen Werte der Voranalyse verglichen mit Werten, die aus Gebäudebegehungen des FP „Insel“ vorliegen, einem Vorläuferforschungsprojekt des Autors („Insel - Internetbasiertes System eines erweiterbaren Lastmanagements zur Integration in virtuelle Kraftwerke), das die DSI Potenziale der öffentlichen Liegenschaften der Stadt untersucht hat. Die Ergebnisse dieser Validierung zeigen, dass der gewählte methodische Ansatz belastbar ist und die Bedarfsklasse „Mittel“ im Durchschnitt gut angenähert wird.
Für die Gruppe der selektierten Gebäude der Stadt Hamburg wurde mit Hilfe der Methode ein als relativ sicher anzusehendes theoretischen DSI-Potenzial von 56 MW aus installierten Lüftungsanlagen und 126 MW aus Kälteanalagen in den selektierten Gebäuden identifiziert. Dies entspricht etwa dem Doppelten der aktuell in Hamburg installierten Leistung aus Windkraft- und PV-Anlagen. Ein wichtiges Ergebnis der Datenauswertung ist die Erkenntnis, dass sich die DSI Potenziale der Gebäude exponentialverteilt darstellen. D. h. es gibt wenige (große) Gebäude in denen ein Großteil der installierten Leistung zu finden ist. Dem steht eine Vielzahl kleinerer Gebäude gegenüber, auf die sich der verbleibende, kleinere Anteil des DSI Potenzials verteilt. Vor diesem Hintergrund lässt sich in etwa 6% der Gebäude 50% des ermittelten theoretischen DSI Potenzials finden, in 25% der Gebäude 83% der Leistung. Das dynamische Verhalten des DSI-Potenzials wurde auf Basis der Standardbetriebszeiten der DINV18599:10 und Wetterdaten des Jahres 2012 abgeschätzt.
Da mit der Methode gebäudeindividuelle DSI Potenziale ermittelt und mit den geografischen Gebäudedaten des ALKIS verknüpft werden, lassen sich die erhaltenen Ergebnisse kartografisch darstellen, was die Ergebniskommunikation für eine Integration der Potenziale in Quartiers- und/oder gesamtstädtische Energiekonzepte fördert. Zur kartografischen Darstellung wurden daher im Rahmen dieser Arbeit zwei Stadtpläne im Format 1:30.000 angefertigt, die die Flurstücke der Stadt Hamburg eingefärbt nach der Höhe des für sie errechneten theoretischen DSI Potenzials für LuK darstellen.Abstract
Constantly rising shares of renewable electricity production lead to stronger needs for and awareness of the potentials arising from Demand Side Integration (DSI). DSI can deliver important contributions to level out fluctuations in residual loads originating from dynamic alternations of the electricity production from renewable sources. Additionally DSI can lower costs in the distribution grid when applying adjustments and reinforcements that become necessary due to the energy turnaround.
This thesis presents a method for calculating the theoretical DSI potential from ventilation and air conditioning (VAC) of non-residential buildings of office-like use with ALKIS as the main data base. ALKIS is a German standardized data model for a joined digital city map and cadastral register. Since by now there are individual ALKIS data sets for a large number of German cities, the method developed in this thesis is at once applicable in all of them.
The thesis concentrates on the ALKIS of Hamburg which contains data about position, size (base area, number of floors) and building usage about all of the approx. 370,000 building of the city. Out of this basic population 7,389 buildings of 17 different “office-related” usage categories were selected. The sample represents 27% of all non-residential buildings of Hamburg (and approx. 0.5% of all non-residential buildings of Germany).
The method makes use of the ALKIS data for a theoretical calculation of the DSI potential using typical zoning profiles for the buildings usage zones, statistical values about the share of the conditioned floor space and specific values for the electrical power needed for VAC. In this context three demand categories are defined: “Low”, “Medium” and “High”. For each building the electrical power needed for VAC (representing the theoretical DSI potential) is calculated for all three demand categories. Prior to this the buildings undergo an ABC analysis separating buildings that are (very) likely (“A” and “B”) to have a DSI potential from VAC from those that are unlikely to have one (“C”).
The method presented is a theoretical one and is expected to be used as a pre-analysis without an actual inspection of the buildings. Therefore validating the method was crucial. For this, field data from inspections of buildings was used which derived from a pre-runner research project called “e-island” (expandable internet sustained load and demand side management). In the “e-island” project the DSI potential of the public properties of the city of Hamburg was researched by the author. Results from the validation show that the method presented is reliable and the demand category “Medium” is approximated on average.
It was found that the selected group of buildings is very likely to yield a theoretical DSI potential of 56 MW from ventilation and 126 MW from cooling. This represents about twice the installed power in renewables from wind turbines and PV in the city of Hamburg.
An important finding of the results is that the DSI potential shows an exponential distribution, i. e. there are few (large) buildings in which the largest share of the total DSI potential of VAC is to be found. Opposed to this there is a high number of small(er) buildings which host only little of the total DSI potential: In only 6% of the buildings about 50% of the theoretical DSI potential is located, 25% of the buildings even account for about 83% of the installed DSI potential (Pareto distribution). The dynamic behavior of the DSI potential was assessed using standard operating times for VAC systems form German standard DINV18599:10 and exemplary weather data from 2012.
Since the method asses the individual DSI potential of buildings and combines this information with data about the geographical location of the buildings from the ALKIS data base, communication of the results and findings is greatly simplified by using color coded maps stating the DSI potential of buildings or parcels. These maps can be used to select and communicate the DSI potentials of single buildings or whole city areas for strategic energy planning. Therefore the thesis presents its findings on two charts scaled 1:30,000 with a color coding representing the range of the theoretical DSI potential from VAC in all the parcels of the city of Hamburg that host non-residential buildings of office-like use
Prevention of cognitive decline after radiation therapy
No full textCentral nervous system tumours are the leading cause of cancer-related deaths in children and the second-most-common malignancy diagnosed after leukaemia. Advances in treatment regimens and multimodal strategies, from early surgical resection, to radiotherapy, complete craniospinal radiation, and chemotherapeutic treatments have greatly improved the chances of survival. However, they are usually accompanied by long-term, late neurocognitive deficits, which, in totality, contribute to reduced quality of life. The aim of this thesis was to illuminate the mechanisms behind the cognitive decline that arises after cranial radiotherapy in childhood cancer survivors and to explore potential treatment strategies to prevent it.Despite the effectiveness of radiotherapy in treating brain cancer, a biomarker that can estimate the extent of IR-induced brain injury and can be correlated with the clinical outcomes has yet to be established. Discovering a measurable molecule, that can be easily quantified in clinical samples that can be obtained through minimally invasive procedures would prove instrumental in predicting the severity of the neurocognitive complications and stratifying patients to the best treatment scheme to prevent or reduce the debilitating decline. In the first study of this thesis, we identified a very promising molecule, EDA2R (ectodysplasin A2 receptor), and we propose it as a potential biomarker. Ectodysplasin A2 receptor is a protein that belongs to the tumour necrosis factor family and is involved a variety of biological processes. After irradiation, we show that EDA2R is highly elevated in the cerebrospinal fluid as well as the blood of mice and is the only marker that remains at high concentrations even at two weeks after the treatment completion. Fulfilling the criteria of a biomarker, it remains to be correlated with cognitive performance in a clinical setting.Among the most dominant hypotheses on the explanation of radiotherapy-induced cognitive decline is the depletion of hippocampal neurogenesis, a physiological process through which new neurons are constantly being born in the from neural stem and progenitor cells (NSPCs), which reside deep in the hippocampus, the centre of memory and learning. The depletion of neurogenesis has also been theorized to derive from the neuroinflammatory microenvironment that radiotherapy induces, which hinders the abilities of NSPCs to differentiate into neurons, and is governed by aberrantly activated microglia. As the resident immune cells of the brain, microglia react immediately to irradiation and undergo a series of changes to adapt to the needs of their niche, and their irradiation-induced diminishing numbers. Through unbiased, longitudinal in vivo studies, we showed that microglia reactivate long after irradiation and adopt unique morphologies and inflammatory profiles in a temporal manner. We observed a biphasic response in the hippocampal tissue, characterized by interferon signalling and proliferation of microglia that leads to neuronal asynchrony, which improves over time, due to the arrival of macrophage-derived microglia. In addition, our investigation revealed subsets of microglia that try to divide even in the presence of DNA damage, leading to senescence.Besides raising and maintaining a neuroinflammatory alarm, microglia are also responsible for clearing dead neural progenitors and cell debris. Irradiation has also been shown to increase the levels of expression of genes that are related to phagocytosis. Several genetic and pharmacological tools have been developed to deplete microglial populations over the years. The usage of these approaches could prove instrumental in understanding the role of microglia in the depletion of neurogenesis. In addition, a study by Willis et al. in 2020 showed that depleting microglia and their subsequent repopulation attenuated cognitive decline in a traumatic brain injury model. With these in mind, we utilized the Cx3cr1CreERt2- YFP/+Rosa26DTA/+ mouse model to deplete microglia before subjecting the animals to cranial radiotherapy. Contrary to what we expected, the absence of microglia increased the production of pro-inflammatory factors and neither the depletion nor the subsequent repopulation had any impact on the loss of immature or proliferating neurons. These findings challenge the proposed role for a pro-inflammatory microenvironment in the dysregulation of hippocampal neurogenesis and suggest that the observed reduction of neurogenesis was solely due to IR..Cranial radiotherapy has been documented to lead to decreases in dendritic density and changes in the spine morphology of the hippocampal neurons. As the main sites of the excitatory synapses, changes in dendrites and spines will often lead to abnormal signaling and dysregulation of the circuit, functions that are essential for cognition, and might also lead to glutamatergic excitotoxicity and neuronal death. Since newborn neurons rely on external inputs from the hippocampal circuit to pass survival checkpoints, strengthening synaptic connectivity might increase the chances of survival of the damaged immature neurons and improve cognitive functions in patients.Memantine is an uncompetitive antagonist of the N-methyl-D-aspartate receptor (NMDAR), which has been shown to exert neuroprotective properties and increases synaptic plasticity and is currently used in the treatment of AlzheimerŐs disease patients. Due to these factors, memantine was considered as a great candidate for ameliorating radiation-induced cognitive decline, and several clinical trials have been completed and are underway since 2013, with very promising results. However, the exact mechanisms of how memantine exerts its neuroprotective effects are still unknown. For the final study of this thesis, we investigated the potential of memantine in preventing loss of neurogenesis. Memantine was administered in mice intraperitonially 30 minutes after cranial irradiation, and then it was supplied in their drinking water to achieve a steady state plasma concentration that recapitulates the clinical practice. Even though our results suggest no change in the numbers of surviving neurons in the hippocampal neurogenic niche, we showed that memantine led to an increase in the arborization of the dendritic processes of the young neurons. These data highlight memantineŐs potential in improving synaptic plasticity, the incorporation of immature neurons in the hippocampal circuitry and, by extension, in attenuating cognitive decline.List of scientific papersI. EDA2R reflects the acute brain response to cranial irradiation in liquid biopsies. Alejandro Lastra Romero, Thea Seitz, Georgios Alkis Zisiadis, Holli Jeffery, Ahmed M Osman*. Neuro Oncol. 2024 Apr 29:noae077. *: Corresponding author(s). https://doi.org/10.1093/neuonc/noae077 II. Microglia Adopt Temporally Specific Subtypes after Irradiation, Correlating with Neuronal Asynchrony. Alejandro Lastra Romero#, Efthalia Preka#, Giusy Pizzirusso, Luis Enrique Arroyo-Garcia, Georgios Alkis Zisiadis, Nuria Oliva-Vilarnau, Thea Seitz, Kai Zhou, Arturo Gonzalez Isla, Lara Friess, Ying Sun, Alia Shamik, Changlian Zhu, Carlos F. D. Rodrigues, AndrŽ Fisahn, Bertrand Joseph, Lena-Maria Carlson, Adamantia Fragkopoulou, Volker M Lauschke, Christer Betsholtz, Ahmed M Osman*, Klas Blomgren*. #These authors contributed equally to this study. *Corresponding author(s). [Manuscript]III. Microglia depletion and repopulation do not alter the effects of cranial irradiation on hippocampal neurogenesis. Kai Zhou#, Georgios Alkis Zisiadis#, Monique Havermans, Adamantia Fragkopoulou, Cecilia Dominguez, Makiko Ohshima, Ahmed M Osman, Carlos F. D. Rodrigues, Klas Blomgren*. #These authors contributed equally to this study. *Corresponding author(s). [Manuscript]IV. Memantine increases the dendritic complexity of hippocampal young neurons in the juvenile brain after cranial irradiation. Georgios Alkis Zisiadis, Androniki Alevyzaki, Elene Nicola, Carlos F. D. Rodrigues, Klas Blomgren, Ahmed M Osman*. Front Oncol. 2023 Oct 4;13:1202200. *Corresponding author(s). https://doi.org/10.3389/fonc.2023.1202200 </p
Everyday Locations as Cues to Smoke: Personalized Environments in Virtual Reality to Elicit Smoking Cravings
No full textSmoking is a leading risk factor negatively impacting the health of people, not only those partaking in it first-hand, but also to those around them. Different methods are available to assist people with quitting smoking, with various degrees of effectiveness. Researchers developing smoking cessation approaches would like to have controlled environments to test how effective they are before offering them as viable options. Virtual reality has been demonstrated to be an efficacious tool for facilitating the presentation of cues aimed at eliciting smoking cravings in the lab. Addiction, however, is a complex matter involving different parts of the brain, and how or when conditioned responses causing smoking cravings are activated depend on the individual in question. There are strong indications that personalization of smoking cues, or in other words using elements relevant in the addiction model of an individual, may elicit higher or at least consistent smoking cravings. The general aim is that developing smoking cessation approaches targeting those most relevant elements may have higher ecological validity and therefore be more effective in assisting people both with quitting smoking and maintaining that behavior change. To assist researchers with testing their smoking cessation approaches using a virtual coach, we have created a system enabling the presentation of virtual environments and facilitating communication between researchers and participants while the latter are viewing them. We have evaluated the effectiveness of our system in eliciting a familiar experience, which we posit is a major component tied to smoking cravings. Our results showed that personalized virtual environments elicited a more familiar experience than non-personalized ones. We also examined the usability of our developed user interface, as well as the sense of presence elicited by our system, both of which received positive scores.<br/
My journey
No full textTitle: Τό ταξίδι μου (My journey) Originally published: Αθήνα, n. p., 1888 Language: Greek The excerpts used are from Ἰωάννης Ψυχάρης, Τό ταξίδι μου, ed. by Alkis Agelou (Athens: Ἐστία: Νεοελληνική Βιβλιοθήκη, 1993), pp. 37–39, 64–67, 75–76, 89. About the author Ioannis (Jean) Psicharis [1854, Odessa – 1929, Paris]: writer, linguist and critic. Psicharis was born to a well-off family. After his mother’s early death his father brought him to Istanbul in 1860, where he spent his childhood. His ..
Thermal comfort conditions in airport terminals: Indoor or transition spaces?
No full textThis paper reports on the investigation of the thermal comfort conditions in three airport terminals in the UK. In the course of seasonal field surveys, the indoor environmental conditions were monitored in different terminal areas and questionnaire-guided interviews were conducted with 3087 terminal users. The paper focuses on the thermal perception, preference and comfort requirements of passengers and terminal staff. The two groups presented different satisfaction levels with the indoor environment and significant differences in their thermal requirements, while both preferring a thermal environment different to the one experienced. The thermal conflict emerges throughout the terminal spaces. The neutral and preferred temperatures for passengers were lower than for employees and considerably lower than the mean indoor temperature. Passengers demonstrated higher tolerance of the thermal conditions and consistently a wider range of comfor
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No full textAbstract. Extraction-Transformation-Loading (ETL) tools are pieces of software responsible for the extraction of data from several sources, their cleansing, customization and insertion into a data warehouse. In this paper, we delve into the logical design of ETL scenarios and provide a generic and customizable framework in order to support the DW designer in his task. First, we present a metamodel particularly customized for the definition of ETL activities. We follow a workflow-like approach, where the output of a certain activity can either be stored persistently or passed to a subsequent activity. Also, we employ a declarative database programming language, LDL, to define the semantics of each activity. The metamodel is generic enough to capture any possible ETL activity. Nevertheless, in the pursuit of higher reusability and flexibility, we specialize the set of our generic metamodel constructs with a palette of frequently-used ETL activities, which we call templates. Moreover, in order to achieve a uniform extensibility mechanism for this library of built-ins, we have to deal with specific language issues. Therefore, we also discuss the mechanics of template instantiation to concrete activities. The design concepts that we introduce have been implemented in a tool
Author Correction: Whole-Genome Sequencing Analysis of Human Metabolome in Multi-Ethnic Populations
No full textCorrection to: Nature Communications 10.1038/s41467-023-38800-2, published online 30 May2023
In this article, the author name Robert E. Gerszten was incorrectly written as Robert E. Gersztern. The original article has been corrected
