Thermal Stability of Hexamethyldisiloxane (MM) for High-Temperature Organic Rankine Cycle (ORC)

The design of efficient Organic Rankine Cycle (ORC) units for the usage of industrial waste heat at high temperatures requires direct contact evaporators without intermediate thermal oil circuits. Therefore, the thermal stability of high-temperature working fluids gains importance. In this study, the thermal degradation of hexamethyldisiloxane (MM) is investigated in an electrically heated tube. Qualitative results concerning remarks on degradation products as well as quantitative results like the annual degradation rate are presented. It is shown that MM is stable up to a temperature of 300 °C with annual degradation rates of less than 3.5%. Furthermore, the break of a silicon–carbon bond can be a main chemical reaction that influences the thermal degradation. Finally, it is discussed how the results may impact the future design of ORC units

An automated neural network-based stage-specific malaria detection software using dimension reduction: the Malaria Stage Classifier

Due to climate change and the COVID-19 pandemic, the number of malaria cases and deaths, caused by the Plasmodium genus, of which P. falciparum is the most common and lethal to humans, increased between 2019 and 2020. Reversing this trend and eliminating malaria worldwide requires improvements in malaria diagnosis, in which artificial intelligence (AI) has recently been demonstrated to have a great potential. One of the main reasons for the use of neural networks (NNs) is the time saving through automatising the process and the elimination of human error. When classifying with two-dimensional images of red blood cells (RBCs), the number of parameters fitted by the NN for the classification of RBCs is extremely high, which strongly influences the performance of the network, especially for training sets of moderate size. The complicated handling of malaria culturing and sample preparation does not only limit the efficiency of NNs due to small training sets, but also because of the uneven distribution of red blood cell (RBC) categories. To boost the performance of microscopy techniques in malaria diagnosis, our approach aims at resolving these drawbacks by reducing the dimension of the input data and by data augmentation, respectively. We assess the performance of our approach on images recorded by light (LM), atomic force (AFM), and fluorescence microscopy (FM). Our tool, the Malaria Stage Classifier, provides a fast, high-accuracy recognition by (1) identifying individual RBCs in multi-cell microscopy images, (2) extracting characteristic one-dimensional cross-sections from individual RBC images. These cross-sections are selected by a simple algorithm to contain key information about the status of the RBCs and are used to (3) classify the malaria blood stages. We demonstrate that our method is applicable to images recorded by various microscopy techniques and available as a software package. • Identifying individual RBCs in multi-cell microscopy images. • Extracting characteristic one-dimensional cross-sections from individual RBC images. These cross-sections are selected by a simple algorithm to contain key information about the status of the RBCs and are used to. • Classify the malaria blood stages. We demonstrate that our method is applicable to images recorded by various microscopy techniques and available as a software package

Ein Umschwung in den letzten Wochen des Landtagswahlkampfes: Befunde einer mehrwelligen Wiederholungsbefragung zur niedersächsischen Landtagswahl 2017

Die niedersächsische Landtagswahl im Oktober 2017 fand im Schatten der vorhergehenden Bundestagswahl statt. Vor dem Hintergrund der zeitlichen Nähe beider Wahlgänge untersucht dieser Aufsatz die Entwicklung bundes- und landesbezogener Einstellungen im Wahlkampfverlauf sowie deren Einfluss auf das Wählerverhalten in Niedersachsen. Eine mehrwellige Wiederholungsbefragung von 1.346 niedersächsischen Wahlberechtigten, die im Rahmen der German Longitudinal Election Study (GLES) durchgeführt wurde, dient als Grundlage der Untersuchung. In quer- und längsschnittlichen Analysen wird gezeigt, dass eine bedeutende Minderheit der Befragten den Wahlentscheidungen auf der Landesebene ebenenspezifische Erwägungen zu Grunde legt. Landesbezogene Einstellungen waren einer von der Bundesebene weitgehend unabhängigen Wahlkampfdynamik unterworfen, die die Wahlabsichten des Elektorats beeinflusst zu haben scheinen. So konnte gerade die niedersächsische SPD die Popularität ihres Spitzenkandidaten in den letzten Wahlkampfwochen steigern und dadurch die CDU in einem Schlussspurt als stärkste Kraft ablösen

Comparison of Cooling System Designs for an Exhaust Heat Recovery System Using an Organic Rankine Cycle on a Heavy Duty Truck

A complex simulation model of a heavy duty truck, including an Organic Rankine Cycle (ORC) based waste heat recovery system and a vehicle cooling system, was applied to determine the system fuel economy potential in a typical drive cycle. Measures to increase the system performance were investigated and a comparison between two different cooling system designs was derived. The base design, which was realized on a Mercedes-Benz Actros vehicle revealed a fuel efficiency benefit of 2.6%, while a more complicated design would generate 3.1%. Furthermore, fully transient simulation results were performed and are compared to steady state simulation results. It is shown that steady state simulation can produce comparable results if averaged road data are used as boundary conditions

Static Analysis Rules of the BPEL Specification: Tagging, Formalization and Tests

In 2007, OASIS finalized their Business Process Execution Language 2.0 (BPEL) specification which defines an XML-based language for orchestrations of Web Services. As the validation of BPEL processes against the official BPEL XML schema leaves room for a plethora of static errors, the specification contains 94 static analysis rules to cover all static errors. According to the specification, any violations of these rules are to be checked by a standard conformant engine at deployment time. When a violation is not detected in BPEL processes during deployment, such errors are only detectable at runtime, making them expensive to find and fix. Due to the large amount of rules, we have created a tag system to categorize them, allowing easier reasoning about these rules. Next, we formalized the static rules and derived test cases based on these formalizations with the aim to evaluate the degree of support for static analysis of BPEL engines. Hence, this work is the foundation of the static analysis capabilities of BPEL engines

Face-to-face conversation style biography work and memory care

Im Hinblick auf die demographische Entwicklung wird für eine ganzheitliche Altenpflege das Weiterbildungskonzept Gesprächsorientierte Biographiearbeit und Erinnerungspflege vorgestellt, dessen Leitmotiv zum einen die Wahrung der Würde alter und kranker Menschen, zum anderen die Steigerung der Arbeitsqualität und -zufriedenheit der in der Altenpflege Tätigen ist. Das didaktisch-methodische Konzept beruht auf den anthropologischen Grundlagen von Logotherapie und Existenzanalyse sowie andragogischen, geragogischen und biographischen Aspekten und wird in der Pflegepraxis evaluiert. Dabei ergibt sich, dass biographische Gespräche trotz des Zeitmangels während der Betreuung und Pflege möglich sind. Sogenannte Fenster- und Türöffner führen in die Vergangenheit und auch dazu, gerontopsychiatrische Veränderungen mit nicht verarbeiteten Traumata in Verbindung zu bringen. Die in der Altenpflege Tätigen werden dafür qualifiziert, Krisengespräche und Lebensbilanzen auf pädagogischen Grundlagen zu begleiten. Narrationsanalysen weisen auf eine Verbesserung der Lebensqualität im Alter durch biographische Gespräche hin.Considering the demographical development the concept of further education of 'face-to-face conversation style biography work and memory care' is presented for the integrated old people's care. Its leading idea is on the one hand the preservation of dignity of old and sick people and on the other hand the increase in the working quality of the personnel who work in old people's homes. The didactical-methodical concept lies on the anthropological basis of logotherapy and existential analysis as well as on the andragogical, geragogical, and biographical aspects, and is evaluated in nursing practice. Despite of the lack of time there is the possibility of biographical talks during care. So-called windows- and door-openers lead into the past and to gerontopsychiatrical changes relating to non-assimilated traumas. The people who work in old people's homes are qualified to accompany crisis-talks and life-outcomes on a pedagogical basis. The narrative analysis indicates an improvement of the quality of life in old age through biographical talks

Alleviating the Curse of Dimensionality in Minkowski Sum Approximations of Storage Flexibility

Many real-world applications require the joint optimization of a large number of flexible devices over time. The flexibility of, e.g., multiple batteries, thermostatically controlled loads, or electric vehicles can be used to support grid operation and to reduce operation costs. Using piecewise constant power values, the flexibility of each device over $d$ time periods can be described as a polytopic subset in power space. The aggregated flexibility is given by the Minkowski sum of these polytopes. As the computation of Minkowski sums is in general demanding, several approximations have been proposed in the literature. Yet, their application potential is often objective-dependent and limited by the curse of dimensionality. We show that up to $2^d$ vertices of each polytope can be computed efficiently and that the convex hull of their sums provides a computationally efficient inner approximation of the Minkowski sum. Via an extensive simulation study, we illustrate that our approach outperforms ten state-of-the-art inner approximations in terms of computational complexity and accuracy for different objectives. Moreover, we propose an efficient disaggregation method applicable to any vertex-based approximation. The proposed methods provide an efficient means to aggregate and to disaggregate energy storages in quarter-hourly periods over an entire day with reasonable accuracy for aggregated cost and for peak power optimization.Comment: 11 pages, 5 figure

Leben in und mit der Schöpfung: Perspektiven einer ökologisch verantworteten Theologie

Die "ökologische Frage" stellt eine der größten Herausforderungen der Menschheit dar. In ihr werden die Konsequenzen der bisherigen Geschichte – der Geschichte des Menschen mit der Natur bzw. der Geschichte der Natur mit dem Menschen – greifbar. So sind in der ökologischen Frage auch grundlegende theologische Aspekte berührt, die insbesondere Fragen der Schöpfungstheologie und daraus abgeleitet eines verantworteten menschlichen Handelns betreffen. Die vorliegende Arbeit versucht eine Rekonstruktion des schöpfungstheologischen Grundmodells und beleuchtet die Beziehungsvarianten der drei Komponenten "Gott", "Mensch" und "Schöpfung". Die Beachtung dieser Grundrelationen ist für eine ökologisch verantwortete Theologie unerlässlich. So soll das Modell des "schöpfungstheologischen Dreiecks" mit diesen aus dem ersten Satz des Credo gewonnenen Komponenten, ausgehend vom handlungsleitenden "Prinzip Liebe" und mit Hilfe der Korrelationsmethode, auf die Thematik "Schöpfung und Ökologie" angewendet werden

Using the Default Option Bias to Influence Decision-Making While Driving

Gaining a better understanding of human–computer interaction in multiple-goal environments, such as driving, is critical as people increasingly use information technology to accomplish multiple tasks simultaneously. Extensive research shows that decision biases can be utilized as effective cues to guide user interaction in single-goal environments. This article is a first step toward understanding the effect of decision biases in multiple-goal environments. This study analyzed data from a field experiment during which a comparison was made between drivers’ decisions on parking lots in a single-goal environment and drivers’ decisions in a multiple-goal environment when being exposed to the default option bias. The article shows that the default option bias is effective in multiple-goal environments. The results have important implications for the design of human–computer interaction in multiple-goal environments