Multi-criteria decision making as a tool for sustainable product development : Benefits and obstacles

For developing sustainable products design engineers need to foresee diverse interrelations between a product's characteristics and its economic, social and environmental impacts. In order to support this complex task a wide range of design methods has been developed. Retrospective analytical methods like Life Cycle Sustainability Assessment (LCSA) require a large amount of information and are thus utilized when important design decisions are already made. Prospective methods are rather generic (e.g. checklists) and too broad to be helpful in concrete design decisions. In this paper, the integration of discrete decision trees with LCSA is proposed for shifting multi-criterial quantitative analysis to earlier development. On the basis of sustainability indicators Pareto-optimal decision-paths for given material- and process alternatives along the product lifecycle can be compared up-front. Resulting benefits and obstacles are illustrated by evaluating value creation options of a bicycle frame

Structural transformations among austenite, ferrite and cementite in Fe–C alloys: A unified theory based on ab initio simulations

AbstractStructural transformations in Fe–C alloys are decisive for the mechanical properties of steels, but their modeling remains a challenge due to the simultaneous changes in Fe lattice and redistribution of C. With a combination of the orientation relationships between austenite, ferrite and cementite, we identify a metastable intermediate structure (MIS), which can serve as a link between the three phases. Based on this framework, different mechanisms depending on the local conditions (C concentration, strain, magnetism) are revealed from ab initio nudged elastic band simulations, which allow us to construct a unified theory for the structural transformations among austenite, ferrite and cementite

Werkzeuge für Code-Reviews und Code-Abnahmen

Code-Reviews sind ein anerkanntes Mittel um die Codequalität zu verbessern. Sie sind heutzutage zum Standard in der Industrie geworden. Bei der Firma AEB werden seit längerem agile Codereviews für den implementierten Programmcode durchgeführt. Jedoch ist man mit dem Rahmen, in dem die Reviews durchgeführt werden, nicht zufrieden. In dieser Arbeit wurden Prüfwerkzeuge für Codereviews getestet und bewertet. Anhand dieser Bewertung wird eine Empfehlung an AEB gegeben um die Unterstützung bei Codereviews zu verbessern.Code reviews are recognized means of improving code quality. They became standard in the industry nowadays. At AEB they use an agile form of code reviews to check their implemented code. Though they are not pleased with the framework around the reviews. In this study code review tools were tested and rated. As a result of this rating a recommendation were given to AEB to get a better support while doing reviews

The Ernst equation and ergosurfaces

We show that analytic solutions \mcE of the Ernst equation with non-empty zero-level-set of \Re \mcE lead to smooth ergosurfaces in space-time. In fact, the space-time metric is smooth near a "Ernst ergosurface" $E_f$ if and only if \mcE is smooth near $E_f$ and does not have zeros of infinite order there.Comment: 23 pages, 4 figures; misprints correcte

Probing bistability in FeII and CoII complexes with an unsymmetrically substituted quinonoid ligand

The generation of molecular platforms, the properties of which can be influenced by a variety of external perturbations, is an important goal in the field of functional molecular materials. We present here the synthesis of a new quinonoid ligand platform containing an [O,O,O,N] donor set. The ligand is derived from a chloranilic acid core by using the [NR] (nitrogen atom with a substituent R) for [O] isoelectronic substitution. Mononuclear FeII and CoII complexes have been synthesized with this new ligand. Results obtained from single crystal X-ray crystallography, NMR spectroscopy, (spectro)electrochemistry, SQUID magnetometry, multi-frequency EPR spectroscopy and FIR spectroscopy are used to elucidate the electronic and geometric structures of the complexes. Furthermore, we show here that the spin state of the FeII complex can be influenced by temperature, pressure and light and the CoII complex displays redox-induced spin-state switching. Bistability is observed in the solid-state as well as in solution for the FeII complex. The new ligand presented here, owing to the [NR] group present in it, will likely have more adaptability while investigating switching phenomena compared to its [O,O,O,O] analogues. Thus, such classes of ligands as well as the results obtained on the reversible changes in physical properties of the metal complexes are likely to contribute to the generation of multifunctional molecular materials

Interleukin-8 Is Activated in Patients with Chronic Liver Diseases and Associated with Hepatic Macrophage Accumulation in Human Liver Fibrosis

BACKGROUND: Interleukin-8 (IL-8, CXCL8) is a potent chemoattractant for neutrophils and contributes to acute liver inflammation. Much less is known about IL-8 in chronic liver diseases (CLD), but elevated levels were reported from alcoholic and hepatitis C-related CLD. We investigated the regulation of IL-8, its receptors CXCR1 and CXCR2 and possible IL-8 responding cells in CLD patients. METHODOLOGY: Serum IL-8 levels were measured in CLD patients (n = 200) and healthy controls (n = 141). Intrahepatic IL-8, CXCR1 and CXCR2 gene expression was quantified from liver samples (n = 41), alongside immunohistochemical neutrophil (MPO) and macrophage (CD68) stainings. CXCR1 and CXCR2 expression was analyzed on purified monocytes from patients (n = 111) and controls (n = 31). In vitro analyses explored IL-8 secretion by different leukocyte subsets. PRINCIPAL FINDINGS: IL-8 serum levels were significantly increased in CLD patients, especially in end-stage cirrhosis. Interestingly, patients with cholestatic diseases exhibited highest IL-8 serum concentrations. IL-8 correlated with liver function, inflammatory cytokines and non-invasive fibrosis markers. Intrahepatically, IL-8 and CXCR1 expression were strongly up-regulated. However, intrahepatic IL-8 could only be associated to neutrophil infiltration in patients with primary biliary cirrhosis (PBC). In non-cholestatic cirrhosis, increased IL-8 and CXCR1 levels were associated with hepatic macrophage accumulation. In line, CXCR1, but not CXCR2 or CXCR3, expression was increased on circulating monocytes from cirrhotic patients. Moreover, monocyte-derived macrophages from CLD patients, especially the non-classical CD16⁺ subtype, displayed enhanced IL-8 secretion in vitro. CONCLUSIONS: IL-8 is strongly activated in CLD, thus likely contributing to hepatic inflammation. Our study suggests a novel role of IL-8 for recruitment and activation of hepatic macrophages via CXCR1 in human liver cirrhosis