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We have demonstrated micromachining of bulk 3C silicon carbide (3C- SiC) wafers by employing 1028nm wavelength femtosecond laser pulses of energy less than 10 nJ directly from a femtosecond laser oscillator, thus eliminating the need for an amplified system and increasing the micromachining speed by more than four orders of magnitude.
We have investigated the ablation behaviour of single crystal SrTiO3 <100> with focus on the influence of the pulse duration at a wavelength of 248 nm. The experiments were performed with KrF-excimer lasers with pulse durations of 34 ns and 500 fs, respectively. Femtosecond-ablation turns out to be more efficient by one order of magnitude and to eliminate the known problem of cracking of SrTiO3 during laser machining with longer pulses. In addition, the cavities ablated with femtosecond pulses display a smoother surface with no indication of melting and well-defined, sharp edges. These effects can be explained by the reduced thermal shock effect on the material by using ultrashort pulses.
The goal of this paper is to design a low-loss 1 x 32 Y-branch optical splitter for optical transmission systems, using two different design tools employing Beam Propagation Method. As a first step, a conventional 1 x 32 Y-branch splitter was designed and simulated in two-dimensional environment of OptiBPM photonic tool. The simulated optical properties feature high loss, high asymmetric splitting ratio and a large size of the designed structure, too. In the second step of this work we propose an optimization of the conventional splitter design leading to suppression of the asymmetric splitting ratio to one-third of its initial value and to the improvement of the losses by nearly 2 dB. In addition, 50% size reduction of the designed structure was also achieved. This length-optimized low-loss splitter was then modelled in a three-dimensional environment of RSoft photonic tool and the simulated results confirm the strong improvement of the optical properties.
Breath analysis offers a non-invasive and rapid diagnostic method for detecting various volatile organic compounds that could be indicators for different diseases, particularly metabolic disorders including type 2 diabetes mellitus. The development of type 2 diabetes mellitus is closely linked to metabolic dysfunction of adipose tissue and adipocytes. However, the VOC profile of human adipocytes has not yet been investigated. Gas chromatography with mass spectrometric detection and head-space needle trap extraction (two-bed Carbopack X/Carboxen 1000 needle traps) were applied to profile VOCs produced and metabolised by human Simpson Golabi Behmel Syndrome adipocytes. In total, sixteen compounds were identified to be related to the metabolism of the cells. Four sulphur compounds (carbon disulphide, dimethyl sulphide, ethyl methyl sulphide and dimethyl disulphide), three heterocyclic compounds (2-ethylfuran, 2-methyl-5-(methyl-thio)-furan, and 2-pentylfuran), two ketones (acetone and 2-pentanone), two hydrocarbons (isoprene and n-heptane) and one ester (ethyl acetate) were produced, and four aldehydes (2-methyl-propanal, butanal, pentanal and hexanal) were found to be consumed by the cells of interest. This study presents the first profile of VOCs formed by human adipocytes, which may reflect the activity of the adipose tissue enzymes and provide evidence of their active role in metabolic regulation. Our data also suggest that a previously reported increase of isoprene and sulphur compounds in diabetic patients may be explained by their production by adipocytes. Moreover, the unique features of this profile, including a high emission of dimethyl sulphide and the production of furan-containing VOCs, increase our knowledge about metabolism in adipose tissue and provide diagnostic potential for future applications.
Product ion distributions resulting from the primary reactions of H3O+ with nine D-labeled volatile organic compounds and the subsequent sequential reactions with H2O have been determined using a Proton Transfer Reaction Time of Flight Mass Spectrometer (PTR-TOF 8000 (IONICON Analytik GmbH)) at various reduced electric field (E/N) values ranging from 80 up to 150 Td and for two different absolute humidity levels of air sample < 0.1% and 5%. The specific D-labeled compounds used in this study are acetone-d6, toluene-d8, benzene-d6, ethanol-d (C2H5OD), ethanol-d2 (CH3CD2OH), ethanol-d6, 2-propanol-d8, 2-propanol-d3 (CD3CH(OH)CH3), and isoprene-d5 (CH2CHC(CD2)CD3). With the exception of the two 2-propanol compounds, non-dissociative proton transfer is the dominant primary reaction pathway. For 2-propanol-d8 and 2-propanol-d3 the major primary reaction channel involved is dissociative proton transfer. However, unlike their undeuterated counterparts, the primary product ions undergo subsequent deuterium/hydrogen isotope exchange reactions with the ever present water in the drift tube, the extent of which of course depends on the humidity within that tube. This exchange leads to the generation of various isotopologue product ions, the product ion branching percentages of which are also
dependent on the humidity in the drift tube. This results in complex mass spectra and the distribution of product ions leads to issues of reduced sensitivity and accuracy. However, the effect of D/H exchange considerably varies between the compounds under study. In the case of acetone-d6 it is very weak (<1%), because the exchange process is not facile when the deuterium is in the methyl functional group. In comparison, the H3O+/ benzene-d6 (C6D6) reaction and sequential reactions with water result in the production of the isotopologue ions C6Dn(H7-n)+ (where n = 0–6). Changing the value of E/N and/or the humidity in the drift tube considerably affects the amount of the isotope exchange reactions and hence the resulting sequential product ion distributions. An important conclusion of the findings from this work is that care must be taken in the choice of an exogenous deuterated compound for use in breath pharmacokinetic studies using proton transfer reaction mass spectrometry; otherwise the resulting D/H exchange processes impose interpretative problems.
© 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license
(http://creativecommons.org/licenses/by/4.0/).
Transparent laser-structured glasses with superhydrophilic properties for anti-fogging applications
(2019)
Ultrashort pulse laser structuring enables direct modification of glass surfaces to generate superhydrophilic properties for anti-fogging applications. This approach makes coatings dispensable and the generated surfaces remain thermally, mechanically, and chemically resistant. However, the laser-generated structures usually cause scattering, which decreases transmission and may disturb the vision through the modified glass in the dry state. The aim of this study was to find a laser-processing strategy to achieve superhydrophilic, anti-fogging properties on glass surfaces with maximum transmission and minimal visual perception of the generated structure. For this purpose, we used an ultrashort-pulsed laser to generate periodic patterns of rippled circles or rough holes with varying pitch. The water contact angle and transmission of the structured glasses were measured as a function of the structured area. It was found that a periodic pattern of holes, which covers less than 1% of the surface, is already sufficient to reach the superhydrophilic state (contact angle < 5°) and provides nearly the same transmission as pristine glass. Pictures of objects imaged through dry, structured glasses, which were placed close to the lens or object, showed in both cases only a minimal decrease of contrast. If this minor drawback can be accepted, this direct laser structuring approach could be an interesting alternative to coating-based techniques and leaves even room to apply additional coatings for the fabrication of multi-functional special glasses.
Varying mindsets in Design Thinking. Why they change during the process and how to nudge them
(2019)
Stress testing is part of today’s bank risk management and often required by the governing regulatory authority. Performing such a stress test with stress scenarios derived from a distribution, instead of pre-defined expert scenarios, results in a systematic approach in which new severe scenarios can be discovered. The required scenario distribution is obtained from historical time series via a Vector-Autoregressive time series model. The worst-case search, i.e. finding the scenario yielding the most severe situation for the bank, can be stated as an optimization problem. The problem itself is a constrained optimization problem in a high-dimensional search space. The constraints are the box constraints on the scenario variables and the plausibility of a scenario.
The latter is expressed by an elliptic constraint. As the evaluation of the stress scenarios is performed with a simulation tool, the optimization problem can be seen as black-box optimization problem. Evolution Strategy, a well-known optimizer for black-box problems, is applied here. The necessary adaptations to the algorithm are explained and a set of different algorithm design choices are investigated. It is shown that a simple box constraint handling method, i.e. setting variables which violate a box constraint to the respective boundary of the feasible domain, in combination with a repair of implausible scenarios provides good results.
In engineering design, optimization methods are frequently used to improve the initial design of a product. However, the selection of an appropriate method is challenging since many
methods exist, especially for the case of simulation-based optimization. This paper proposes a systematic procedure to support this selection process. Building upon quality function deployment, end-user and design use case requirements can be systematically taken into account via a decision
matrix. The design and construction of the decision matrix are explained in detail. The proposed
procedure is validated by two engineering optimization problems arising within the design of box-type boom cranes. For each problem, the problem statement and the respectively applied optimization methods are explained in detail. The results obtained by optimization validate the use
of optimization approaches within the design process. The application of the decision matrix shows the successful incorporation of customer requirements to the algorithm selection.
Zusammenfassung: Eine umfassende Literaturrecherche (Comprehensive Literature Search, CLS) bezeichnet eine umfangreiche und aufwändige Recherche mit dem Ziel, möglichst alle Studien zur Beantwortung einer zugrundeliegenden Forschungsfrage im Rahmen einer systematischen Übersichtsarbeit zu identifizieren. Konkrete Empfehlungen oder eine Definition des Begriffs CLS gibt es jedoch nicht. Der vorliegende Beitrag führt in eine Rahmung der CLS ein, stellt die damit einhergehenden Herausforderungen dar und weist auf methodische Implikationen sowie mögliche zukünftige Forschungsbereiche hin.
Adult muscle carnitine palmitoyltransferase (CPT) II deficiency is a rare autosomal recessive disorder of long-chain fatty acid metabolism. It is typically associated with recurrent episodes of exercise-induced rhabdomyolysis and myoglobinuria, in most cases caused by a c.338C > T mutation in the CPT2 gene. Here we present the pedigree of one of the largest family studies of CPT II deficiency caused by the c.338C > T mutation, documented so far. The pedigree comprises 24 blood relatives
of the index patient, a 32 year old female with genetically proven CPT II deficiency. In total, the mutation was detected in 20 family members, among them five homozygotes and 15 heterozygotes. Among all homozygotes, first symptoms of CPT II deficiency occurred during childhood. Additionally, two already deceased relatives of the index patient were carriers of at least one copy of the genetic variant, revealing a remarkably high prevalence of the c.338C > T mutation within the tested family. Beside the index patient, only one individual had been diagnosed with CPT II deficiency prior to this study and three cases of CPT II deficiency were newly detected by this family study, pointing
to a general underdiagnosis of the disease. Therefore, this study emphasizes the need to raise awareness of CPT II deficiency for correct diagnosis and accurate management of the disease.
Breath analysis holds great promise for real-time and non-invasive medical diagnosis. Thus, there is a considerable need for simple-in-use and portable analyzers for rapid detection of breath indicators for different diseases in their early stages. Sensor technology meets all of these demands. However, miniaturized breath analyzers require adequate breath sampling methods. In this context, we propose non-contact sampling; namely the collection of breath samples by exhalation from a distance into a miniaturized collector without bringing the mouth into direct contact with the analyzing device. To evaluate this approach different breathing maneuvers have been tested in a real-time regime on a cohort of 23 volunteers using proton transfer reaction mass spectrometry. The breathing maneuvers embraced distinct depths of respiration, exhalation manners, size of the mouth opening and different sampling distances. Two inhalation modes (normal, relaxed breathing and deep breathing) and two exhalation manners (via smaller and wider lips opening) forming four sampling scenarios were selected. A sampling distance of approximately 2 cm was found to be a reasonable trade-off between sample dilution and requirement of no physical contact of the subject with the analyzer. All four scenarios exhibited comparable measurement reproducibility spread of around 10%. For normal, relaxed inspiration both dead-space and end-tidal phases of exhalation lasted approximately 1.5 s for both expiration protocols. Deep inhalation prolongs the end-tidal phase to about 3 s in the case of blowing via a small lips opening, and by 50% when the air is exhaled via a wide one. In conclusion, non-contact breath sampling can be considered as a promising alternative to the existing breath sampling methods, being relatively close to natural spontaneous breathing.
In dieser Arbeit wird Supervised Learning verwendet, um die Zuverlässigkeit von Schweißverbindungen zu evaluieren.
Um die Schweißqualität zu bestimmen, wurden End of Life Tests durchgeführt. Für die statistische Auswertung und Vorhersage der zu erwartenden Lebensdauer, wurden die Daten basierend auf einer logarithmischen Normalverteilung und mit einer multivariablen linearen Regression modelliert. Um die signifikanten Einflussfaktoren zu identifizieren, wurde eine schrittweise Regression genutzt. Die Ergebnisse zeigen, dass das entwickelte Modell die Zuverlässigkeit und Lebensdauer der Schweißverbindung akkurat abbildet und präzise Vorhersagen liefern kann.
Background: Peripheral arterial disease (PAD) is a common and severe disease with a highly increased cardiovascular morbidity and mortality. Through the circulatory disorder and the linked undersupply of oxygen carriers in the lower limbs, the ongoing decrease of the pain-free walking distance occurs with a significant reduction in patients’ quality of life. Studies including activity monitoring for patients with PAD are rare and digital support to increase activity via mobile health technologies is mainly targeted at patients with cardiovascular disease in general. The special requirement of patients with PAD is the need to reach a certain pain level to improve the pain-free walking distance. Unfortunately, both poor adherence and availability of institutional resources are major problems in patient-centered care.
Objective: The objective of this trackPAD pilot study is to evaluate the feasibility of a mobile phone–based self tracking app to promote physical activity and supervised exercise therapy (SET) in particular. We also aim for a subsequent patient centered adjustment of the app prototype based on the results of the app evaluation and process evaluation.
Methods: This study was designed as a closed user group trial, with assessors blinded, and parallel group study with face-to-face components for assessment with a follow-up of 3 months. Patients with symptomatic PAD (Fontaine stage IIa or IIb) and possession of a mobile phone were eligible. Eligible participants were randomly assigned into study and control group, stratified by their distance covered in the 6-min walk test, using the software TENALEA. Participants randomized to the study group received usual care and the mobile intervention (trackPAD) for the follow-up period of 3 months, whereas participants randomized to the control group received only usual care. TrackPAD records the frequency and duration of training sessions and pain level using manual user input. Clinical outcome data were collected at the baseline and after 3 months via validated tools (6-min walk test, ankle-brachial index, and duplex ultrasound at the lower arteries) and self-reported quality of life. Usability and quality of the app was determined using the user version of the Mobile Application Rating Scale.
Results: The study enrolled 45 participants with symptomatic PAD (44% male). Of these participants, 21 (47%) were randomized to the study group and 24 (53%) were randomized to the control group. The distance walked in the 6-min walk test was comparable in both groups at baseline (study group: mean 368.1m [SD 77.6] vs control group: mean 394.6m [SD 100.6]).
Conclusions: This is the first trial to test a mobile intervention called trackPAD that was designed especially for patients with PAD. Its results will provide important insights in terms of feasibility, effectiveness, and patient preferences of an app-based mobile intervention supporting SET for the conservative treatment of PAD.
The humidification-dehumidification process (HDH) for desalination is a promising technology to address water scarcity issues in rural regions. However, a low humidifier efficiency is a weakness of the process. Bubble column humidifiers (BCH) are promising for HDH, as they provide enhanced heat and mass transfer and have low maintenance requirements. Previous studies of HDH-systems with BCHs draw different conclusions regarding the impact of superficial air velocity and liquid height on the humidification. Furthermore, the impact of flow characteristics has never been investigated systematically at all. In this study, an optimized BCH test setup that allows for optical analysis of the humidifier is used and evaluated. Our test setup is validated, since the influence of water temperature on the humidification, which is exponential, is reproduced. Measurements with seawater show that the normalised system productivity is increased by about 56 % with an increase in superficial air velocity from 0.5 to 5 cm/s. Furthermore, the system productivity is increased by around 29 % with an increase in liquid height from 60 to 378 mm. While the impact of superficial air velocity can be traced back to temperature changes at the humidifier and dehumidifier outlets, the impact of liquid height is shown to be caused by a smaller heat loss surface in the humidifier with an increase in liquid height. For the impact of sieve plate orifice diameter, a clear influence on the humidification is not apparent, this parameter needs to be investigated further. Finally, our new test setup allows for analysing the humidification of air (1) in a systematic way, (2) in relevant measurement ranges and (3) in comparison with optical analyses of the flow characteristics.
Greater specific energy densities in lithium-ion batteries can be achieved by using three-dimensional (3D) porous current collectors, which allow for greater areal mass loadings of the electroactive material. In this paper, we present the use of embroidered current collectors for the preparation of thick, pouch-type Li-ion batteries. Experiments were performed on LiFePO 4 (LFP) water-based slurries using styrene-butadiene rubber (SBR) as binder and sodium carboxymethyl cellulose (CMC) as thickener, and formulations of different rheological characteristics were investigated. The electrochemical performance (cyclic voltammetry, rate capability) and morphological characteristics of the LFP half-pouch cells (X-ray micro computed tomography and scanning electron microscopy) were compared between the formulations. An optimum electrode formulation was identified, and a mechanism is proposed to explain differences between the formulations. With the optimum electrode formulation, 350 µm casted electrodes with high mechanical stability were achieved. Electrodes exhibited 4–6 times greater areal mass loadings (4–6 mAh cm −2 ) and 50% greater electroactive material weight than with foils. In tests of half- and full-pouch embroidered cells, a 50% capacity utilization at 1C-rate and 11% at 2C-rate were observed, with a full recovery at C/5-rate. The cycling stability was also maintained over 55 cycles.
Gas hydrates are usually synthesized by bringing together a pressurized gas and liquid or solid water. In both cases, the transport of gas or water to the hydrate growth site is hindered once an initial film of hydrate has grown at the water–gas interface. A seemingly forgotten gas-phase technique overcomes this problem by slowly depositing water vapor on a cold surface in the presence of the pressurized guest gas. Despite being used for the synthesis of low-formation-pressure hydrates, it has not yet been tested for hydrates of CO 2 and CH 4 . Moreover, the potential of the technique for the study of hydrate decomposition has not been recognized yet. We employ two advanced implementations of the condensation technique to form hydrates of CO 2 and CH 4 and demonstrate the applicability of the process for the study of hydrate decomposition and the phenomenon of self-preservation. Our results show that CO 2 and CH 4 hydrate samples deposited on graphite at 261–265 K are almost pure hydrates with an ice fraction of less than 8%. Rapid depressurization experiments with thin deposits (approx. 330 mm thickness) of CO 2 hydrate on an aluminum surface at 265 K yield identical dissociation curves when the deposition is done at identical pressure. However, hydrates deposited at 1 MPa almost completely withstand decomposition after rapid depressurization to 0.1 MPa, while samples deposited at 2 MPa decompose 7 times faster. Therefore, this synthesis technique is not only applicable for the study of hydrate decomposition but can also be used for the controlled deposition of a super-preserved hydrate.
Investigation of non-uniformly emitting optical fiber diffusers on the light distribution in tissue
(2020)
The Digital Factory Vorarlberg is the youngest Research Center of Vorarlberg University of Applied Sciences. In the lab of the research center a research and learning factory has been established for educating students and employees of industrial partners. Showcases and best practice scenarios for various topics of digitalization in the manufacturing industry are demonstrated. In addition, novel methods and technologies for digital production, cloud-based manufacturing, data analytics, IT- and OT-security or digital twins are being developed. The factory comprises only a minimum core of logistics and fabrication processes to guarantee manageability within an academic setup. As a product, fidget spinners are being fabricated. A webshop allows customers to individually design their products and directly place orders in the factory. A centralized SCADA-System is the core data hub for the factory. Various data analytic tools and methods and a novel database for IoT-applications are connected to the SCADA-System. As an alternative to on premise manufacturing, orders can be pushed into a cloud-based manufacturing platform, which has been developed at the Digital Factory. A broker system allows fabrication in distributed facilities and offers various optimization services. Concepts, such as outsourcing product configuration to customers or new types of engineering services in cloud-based manufacturing can be explored and demonstrated. In this paper, we present the basic concept of the Digital Factory Vorarlberg, as well as some of the newly developed topics.
Daten werden heute oft auch als das «neue Gold» bezeichnet. Denn die letzten Jahre haben gezeigt, dass Daten die Grundlage erstaunlicher unter- nehmerischer Erfolgsgeschichten sein können. Dabei ist die Arbeit mit Daten nicht grundlegend neu. Vielmehr geht es heute im Vergleich zu früher um nahezu unendlich grossen Mengen an Daten, die im Rahmen nahezu aller denkbaren Prozesse oder Schnittstellen gesammelt, gespeichert und ausgewertet werden können. Unter anderem beinhaltet dies Maschinendaten, unternehmens- interne Prozesse oder Daten über Kunden und den Markt, welche die Grundlage für lernende Systeme (Künstliche Intelligenz) bilden. Wir können heute davon ausgehen, dass künftig nicht mehr die technische Machbarkeit, sondern die mensch- liche Vorstellungskraft die Grenzen des Möglichen definiert.
Bekannt sind vor allem etliche Erfolgsgeschichten von Grossunternehmen, die ihr Geschäft auf Daten aufbauen. Etablierte KMU sind hingegen noch zögerlicher, mit Daten zu arbeiten und diese wertschöpfend einzusetzen. Diese Broschüre geht auf die besondere Situation von KMU im Umgang mit Daten und Data Science ein. Denn auch für KMU kann es lohnend oder sogar zwingend notwendig sein, sich mit dem Thema «Data Science» zu beschäftigen. Daten und Data Science bieten grosse
Chancen, sie können aber auch zu einer Bedrohung im Wettbewerb werden. Und, zu lange warten sollten KMU nicht, die Zeit drängt. Denn Geschwindigkeit ist einer der zentralen Wettbewerbsfaktoren im digitalen Zeitalter. Das IBH-Lab KMUdigital unter- stützt KMU dabei, den herausfordernden Weg in eine digitale Zukunft schneller und einfacher zu gehen.
Diese Broschüre geht daher insbesondere auf die Rolle von Daten und Data Science für KMU in der Bodenseeregion ein. Sie stellt eine Zusammen- fassung ausgewählter Erkenntnisse und Handlungs- empfehlungen dar, die wir in einem zweijährigen Forschungsprojekt gemeinsam mit 16 Unternehmen aus der Bodenseeregion gewinnen konnten. Die Erkenntnisse sollen KMU bei der Nutzung von Daten anhand von Data Science unterstützen. Dabei ist es kein Ziel, dass KMU zu einem «kleinen Google» werden. Vielmehr braucht es KMU- spezifische Lösungen und Überlegungen, wie mit Daten sinnvoll, zielorientiert und ressourcen- schonend umgegangen werden kann. Wie kann das aussehen? Welche Chancen, Herausforderungen und Lösungen bieten sich KMU vor dem Hinter- grund ihrer besonderen Situation? Was muss dazu im Unternehmen verändert werden? Welche Unterschiede bestehen im Vergleich zu Gross- unternehmen auf diesem Weg?
Diese und weitere Fragen stehen im Mittelpunkt des vorliegenden Projektberichts zum Einzelprojekt «Data Science für KMU leicht gemacht» oder kurz «Data Science 4 KMU» bzw. «Data4KMU», welches unter dem Dach des IBH-Labs KMUdigital in den Jahren 2018 bis 2019 durchgeführt wurde. Dazu werden Daten und Data Science aus mehreren Perspektiven betrachtet, die nicht unabhängig voneinander sind: Strategie und Geschäftsmodell, Services und Prozesse, Leadership, HRM und
Organisation, Organisationskultur und Ganzheitichkeit, sowie Technologie. Diese Perspektiven greifen wir in den nachfolgenden Kapiteln auf.
Die vorliegende Broschüre wäre ohne die wertvolle Unterstützung der Praxispartner des Projektes, des Managements des IBH-Labs KMUdigital sowie ohne die finanzielle Projektförderung durch die Inter- nationale Bodenseehochschule (IBH) und Interreg nicht möglich gewesen. Ihnen allen gilt unser ganz besonderer Dank!
Lead–magnesium niobate lead titanate (PMN-PT) has been proven as an excellent material for sensing and actuating applications. The fabrication of advanced ultra-small PMN-PT-based devices relies on the availability of sophisticated procedures for the micro-machining of PMN-PT thin films or bulk substrates. Approaches reported up to date include chemical etching, excimer laser ablation, and ion milling. To ensure an excellent device performance, a key mandatory feature for a micro-machining process is to preserve as far as possible the crystalline quality of the substrates; in other words, the fabrication method must induce a low density of cracks and other kind of defects. In this work, we demonstrate a relatively fast procedure for the fabrication of high-quality PMN-PT micro-machined actuators employing green femtosecond laser pulses. The fabricated devices feature the absence of extended cracks and well-defined edges with relatively low roughness, which is advantageous for the further integration of nanomaterials onto the piezoelectric actuators.
The Convention on the Rights of the Child (CRC) is a human rights framework in the context of multi-level governance child protection policies central to social work education and practice (United Nations, 1989). In line with this statement, children’s rights-based education introduces undergraduate social work students to the principles of the CRC, namely participation, protection, harm prevention and provision, to facilitate knowledge acquisition by building core competencies for critical practice (IFSW, 2002). It equips social workers with analytical and advocacy skills that foster critical thinking and creativity in the juxtaposition between child protection, autonomy and self-determination.
This chapter provides insights for social work education to locate and analyse the underlying casualties of social problems using a problem and resource framework, the w-questions (Geiser, 2015). The framework is used to develop theory driven social work interventions as illustrated against the backdrop the anonymised case study, Amira, an accompanied child asylum seeker in Austria (Fritsche, Glawischnig, & Wolfsegg, 2019). Correspondingly, CRC is addressed along a continuum between human needs fulfilment and human right entitlements (Obrecht, 2009; IFSW, 2002; Ife, 2012). The concept of need is understood as tension in our concrete biological and psychological bio-values and states (Obrecht, 2009, p. 27). The assertion is that when children lack support or are obstructed from achieving their equal right to education due to social, cultural or economic barriers, this exacerbates social marginalisation because it deprives them of membership in the school social system. Social marginalisation thwarts the fulfilment of needs and weakens social cohesion by causing alienation and anomie (Mayrhofer, 2015). The tentative conclusion is that knowledge and practice models that link human needs and children’s rights equip social workers with the expertise to reduce children’s vulnerability whilst strengthening their protection, autonomy and self-determination.
Wer wünscht ihn nicht: den intelligenten, effizienten und wirtschaftlichen Herstellungsprozess? Viele Firmen setzten aktuell auf die Digitalisierung und verbessern so die eigene sowie die mit externen Stellen vernetzte Produktion. Die Digitalisierung bringt einerseits Fortschritt, zeigt aber auch die zunehmende Komplexität der heutigen Produktionsnetzwerke auf. Zahlreiche Entscheidungen sind zu fällen, um einen effizienten und sicheren Austausch mit verschiedenen Betrieben zu gewährleisten.
Ein Blick auf vorhandene Modelle kann da weiterhelfen: Im Projekt i4Production des IBH-Labs KMUdigital haben Teams an drei Standorten in den drei Nachbarländern Deutschland (HTWG Konstanz), Österreich (FH Vorarlberg) und der Schweiz (NTB Buchs, RhySearch) an einer vernetzten Prozesslandschaft gearbeitet. In einem gemeinsamen, standardisierten Automatisierungskonzept wird in der international vernetzten Modellfabrik ein cyberphysisches System (CPS) in Form eines kundenindividualisierten Modellfahrzeuges produziert, das durch den Kunden in diversen Varianten zusammengestellt oder individuell konstruiert werden kann. Die dezentrale Produktion erlaubt eine Datenweitergabe über die Landesgrenzen in Echtzeit und bildet die Simulation eines länderübergreifenden Business-Eco-Systems ab.
Die Erkenntnisse des Projekts i4Production zeigen wie in kleineren und mittleren Unternehmen (KMU) eine verteilte Produktion, inklusive der Einbindung von Mitarbeitenden und Kunden in eine digitalisierte, hochautomatisierte und kundenindividuelle Produktion, organisiert werden kann.
Für Unternehmen wird diese Industrie 4.0-Prozesslandschaft als Modell für die eigene Fertigung in dem neu aufgebauten CNC Präzisionsfertigungslabor „Werkstatt4“ bei RhySearch öffentlich zur Verfügung gestellt. Die „Werkstatt4“ bietet KMU ein digitales Prozessumfeld, in dem getestet werden kann, mit welchen Maßnahmen der eingangs gestellte Wunsch zur optimierten Herstellung, seinen Weg in die Realität finden kann.
Im Folgenden stellen wir Ihnen das Konzept der internationalen Musterfabrik i4Production, die diversen Arbeitsschritte an den beteiligten Hochschulen sowie die wichtigsten Erkenntnisse für KMU der Bodenseeregion vor. Gerne unterstützen wir Sie bei der Gestaltung des Wandels hin zum Unternehmen 4.0: Sprechen Sie uns an.
Post-operative isoflurane has been observed to be present in the end-tidal breath of patients who have undergone major surgery, for several weeks after the surgical procedures. A major new noncontrolled, non-randomized, and open-label approved study will recruit patients undergoing various surgeries under different inhalation anaesthetics, with two key objectives, namely to record the washout characteristics following surgery, and to investigate the influence of a patient’s health and the duration and type of surgery on elimination. In preparation for this breath study using proton transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS), it is important to identify first the analytical product ions that need to be monitored and under what operating conditions. In this first paper of this new research programme, we present extensive PTR-TOF-MS studies of three major
anaesthetics used worldwide, desflurane (CF3CHFOCHF2), sevoflurane ((CF3)2CHOCH2F), and isoflurane (CF3CHClOCHF2) and a fourth one, which is used less extensively, enflurane (CHF2OCF2CHFCl), but is of interest because it is an isomer of isoflurane. Product ions are identified as a function of reduced electric field (E/N) over the range of approximately 80 Td to 210 Td, and the effects of operating the drift tube under ‘normal’ or ‘humid’ conditions on the intensities of the product ions are presented. To aid in the analyses, density functional theory (DFT) calculations of the proton affinities and the gas-phase basicities of the anaesthetics have been determined. Calculated energies for the ion-molecule reaction pathways leading to key product ions, identified as ideal for monitoring the inhalation anaesthetics in breath with a high sensitivity and selectivity, are also presented.
Clathrate hydrates, or hydrates for short, are inclusion compounds in which water molecules form a hydrogen-bonded host lattice that accommodates the guest molecules. While vast amounts of hydrates are known to exist in seafloor sediments and in the permafrost on Earth, these occurrences might be dwarfed by the amounts of hydrates occurring in space and on celestial bodies. Since methane is the primary guest molecule in most of the natural occurrences on Earth, hydrates are considered a promising source of energy. Moreover, the ability of one volume of hydrate to store about 170 volumes of gas, make hydrates a promising functional material for various industrial applications. While the static properties of hydrates are reasonably well known, the dynamics of hydrate formation and decomposition are insufficiently understood. For instance, the stochastic period of hydrate nucleation, the memory effect, and the self-preservation phenomenon complicate the development of predictive models of hydrate dynamics. Additionally, the influence of meso- and macroscopic defects as well as the roles of mass and heat transport on different length scales remain to be clarified.
Due to its non-invasive and non-destructive nature and the high spatial resolution of approx. 1µm or even less, micro-computed X-ray attenuation tomography ( µCT ) seems to be the perfect method for the study of the evolving structures of forming or decomposing hydrates on the meso- and macroscopic length scale. However, for the naturally occurring hydrates of low atomic number guests the contrast between hydrate, ice, and liquid water is typically very weak because of similar X-ray attenuation coefficients. So far, good contrast was only restricted to synchrotron beamline experiments which utilize the phase information of monochromatic X-rays.
In this thesis it is shown that with the help of a newly developed sample cell, a contrast between the hydrate and the ice phase sufficiently good for the reliable segmentation of the materials can also be achieved in conventional tube-based µCT. An accurate pressure and temperature management, i.e., the added functionality of the cell, further allows for cross-correlation of structural and thermodynamic data. The capability of this µCT setup is demonstrated in a series of studies on the formation and decomposition of hydrates which yield new insights for the development of a novel route to hydrate synthesis. At last, this thesis points towards possibilities how better models of hydrate formation and decomposition can be developed with the aid of µCT and computer simulations.
Wir untersuchen Gemeinsamkeiten und Unterschiede partizipativer Projekte auf Gemeindeebene in der Bodenseeregion. Ziel dabei ist es, einerseits Chancen und Stolpersteine von partizipativen Projekten für Gemeinden zu identifizieren. Andererseits entwickeln wir den Resilienzbegriff aus Psychologie und BWL weiter für Gemeinden und fragen uns, wie Partizipation die Resilienz einer Gemeinde beeinflusst.
For a given set of banks, how big can losses in bad economic or financial scenarios possibly get, and what are these bad scenarios? These are the two central questions of stress tests for banks and the banking system. Current stress tests select stress scenarios in a way which might leave aside many dangerous scenarios and thus create an illusion of safety; and which might consider highly implausible scenarios and thus trigger a false alarm. We show how to select scenarios systematically for a banking system in a context of multiple credit exposures. We demonstrate the application of our method in an example on the Spanish and Italian residential real estate exposures of European banks. Compared to the EBA 2016 stress test our method produces scenarios which are equally plausible as the EBA stress scenario but yield considerably worse system wide losses.
Seit einigen Jahren beschäftigen sich immer mehr Autor*innen mit der Frage, welche Handreichungen Mitarbeitende im Gesundheitssystem brauchen, um adäquater auf die Bedürfnisse älterer LGBTQI* Personen einzugehen, deren (pflegerische) Anliegen nicht erkannt werden, von schwer zu überwindenden Barrieren im Gesundheitssystem berichten und die sich diskriminiert fühlen. Der Fokus der Publikationen liegt auf der sexuellen Orientierung und / oder der Genderidentität, einem Teilaspekt der Identität einer Person. Je nach Kontext und Personen sind andere Teilidentitäten, wie z.B. Familienstatus, Alter, Ethnizität, Teilhabe an sozialen Gruppen unterschiedlich stark berücksichtigt. In einer qualitativen Studie wurden, unter Integration der autoethnographischen Methode, acht Männer zwischen 53 und 75 Jahren aus den Niederlanden und Deutschland in autobiografischen-narrativen Interviews befragt, inwiefern die Coronapandemie ihre Vorstellungen vom gesunden Altern verändert hat. Alle Männer hatten komplexe Biografien, gekennzeichnet von Partnerverlust, Arbeitslosigkeit, Altersfragen, familiären und gesundheitlichen Herausforderungen neben anderen identitätsstiftenden Faktoren. Aber alle identifizierten sich seit ihrer Jugend mit ihrer sexuellen oder Genderidentität, hatten aus vielen Krisen gelernt und sorgten mit einem für sich klaren Management, dass sie auch im Alter gesund bleiben würden – Autonomie stand hoch im Kurs! Die Person nicht nur auf die Zugehörigkeit zur LGBTQI* Gruppe zu reduzieren, sondern in ihrer gesamten Identität in den Gesundheitseinrichtungen zu berücksichtigen kennzeichnet eine adäquate Pflege.
Over the last years, polymers have gained great attention as substrate material, because of the possibility to produce low-cost sensors in a high-throughput manner or for rapid prototyping and the wide variety of polymeric materials available with different features (like transparency, flexibility, stretchability, etc.). For almost all biosensing applications, the interaction between biomolecules (for example, antibodies, proteins or enzymes) and the employed substrate surface is highly important. In order to realize an effective biomolecule immobilization on polymers, different surface activation techniques, including chemical and physical methods, exist. Among them, plasma treatment offers an easy, fast and effective activation of the surfaces by micro/nanotexturing and generating functional groups (including carboxylic acids, amines, esters, aldehydes or hydroxyl groups). Hence, here we present a systematic and comprehensive plasma activation study of various polymeric surfaces by optimizing different parameters, including power, time, substrate temperature and gas composition. Thereby, the highest immobilization efficiency along with a homogenous biomolecule distribution is achieved with a 5-min plasma treatment under a gas composition of 50% oxygen and nitrogen, at a power of 1000 W and a substrate temperature of 80 C. These results are also confirmed by different surface characterization methods, including SEM, XPS and contact angle measurements.
Electric cell-substrate impedance spectroscopy (ECIS) enables non-invasive and continuous read-out of electrical parameters of living tissue. The aim of the current study was to investigate the performance of interdigitated sensors with 50 μm electrode width and 50 μm inter-electrode distance made of gold, aluminium, and titanium for monitoring the barrier properties of epithelial cells in tissue culture. At first, the measurement performance of the photolithographic fabricated sensors was characterized by defined reference electrolytes. The sensors were used to monitor the electrical properties of two adherent epithelial barrier tissue models: renal proximal tubular LLC-PK1 cells, representing a normal functional transporting epithelium, and human cervical cancer-derived HeLa cells, forming non-transporting cancerous epithelial tissue. Then, the impedance spectra obtained were analysed by numerically fitting the parameters of the two different models to the measured impedance spectrum. Aluminium sensors proved to be as sensitive and consistent in repeated online-recordings for continuous cell growth and differentiation monitoring assensors made of gold, the standard electrode material. Titanium electrodes exhibited an elevated intrinsic ohmic resistance incomparison to gold reflecting its lower electric conductivity. Analysis of impedance spectra through applying models and numerical data fitting enabled the detailed investigation of the development and properties of a functional transporting epithelial tissue using either gold or aluminium sensors. The result of the data obtained, supports the consideration of aluminium and titanium sensor materials as potential alternatives to gold sensors for advanced application of ECIS spectroscopy.
Real-time measurements of the differences in inhaled and exhaled, unlabeled and fully deuterated acetone concentration levels, at rest and during exercise, have been conducted using proton transfer reaction mass spectrometry. A novel approach to continuously differentiate between the inhaled and exhaled breath acetone concentration signals is used. This leads to unprecedented fine grained data of inhaled and exhaled concentrations. The experimental results obtained are compared with those predicted using a simple three compartment model that theoretically describes the influence of inhaled concentrations on exhaled breath concentrations for volatile organic compounds with high blood:air partition coefficients, and hence is appropriate for acetone. An agreement between the predicted and observed concentrations is obtained. Our results highlight that the influence of the upper airways cannot be neglected for volatiles with high blood:air partition coefficients, i.e. highly water soluble volatiles.
Business Analytics zählt zu den Zukunftsthemen im Controlling. In der Controllinglehre spielt Analytics bisher aber nur eine untergeordnete Rolle. Der Beitrag beschreibt ein innovatives Lehrprojekt, das Studierende im Masterstudium Accounting, Controlling & Finance an der FH Vorarlberg befähigt, controllingrelevante Fragestellungen im Kontext von Business Analytics eigenständig zu beantworten. Gleichzeitig erlernen die Studierenden den Umgang mit der Open-Source-Software R.
The importance of Agent-Based Simulation (ABS) as scientific method to generate data for scientific models in general and for informed policy decisions in particular has been widely recognised. However, the important technique of code testing of implementations like unit testing has not generated much research interested so far. As a possible solution, in previous work we have explored the conceptual use of property-based testing. In this code testing method, model specifications and invariants are expressed directly in code and tested through automated and randomised test data generation. This paper expands on our previous work and explores how to use property-based testing on a technical level to encode and test specifications of ABS. As use case the simple agent-based SIR model is used, where it is shown how to test agent behaviour, transition probabilities and model invariants. The outcome are specifications expressed directly in code, which relate whole classes of random input to expected classes of output. During test execution, random test data is generated automatically, potentially covering the equivalent of thousands of unit tests, run within seconds on modern hardware. This makes property-based testing in the context of ABS strictly more powerful than unit testing, as it is a much more natural fit due to its stochastic nature.
Design and optimization of 1x2N Y-branch optical splitters for telecommunication applications
(2020)
This paper presents the design and optimization of 1x2N Y-branch optical splitters for telecom applications. A waveguide channel profile, used in the splitter design, is based on a standard silica-on-silicon material platform. Except for the lengths of the used Y-branches, design parameters such as port pitch between the waveguides and simulation parameters for all splitters were considered fixed. For every Y-branch splitter, insertion loss, non-uniformity, and background crosstalk are calculated. According to the minimum insertion loss and minimum non-uniformity, the optimum length for each Y-branch is determined. Finally, the individual Y-branches are cascade joined to design various Y-branch optical splitters, from 1x2 to 1x64.
ÖMG Conference 2019
(2019)
We present the technological verification of a size-optimized 160-channel, 50-GHz silicon nitride-based AWG-spectrometer. The spectrometer was designed for TM-polarized light with a central wavelength of 850 nm applying our proprietary “AWG-Parameters” tool. For the simulations of AWG layout, the WDM PHASAR photonics tool from Optiwave was used. The simulated results show satisfying optical properties of the designed AWG-spectrometer. However, the high-channel count causes a large AWG size with standard design approaches. To solve this problem we designed a special taper enabling the reduction of AWG structure by about 15% while keeping the same optical properties. The AWG design was fabricated and the measured spectra not only confirm the proposed size-reduction but also the improvement of optical properties of the size-optimized AWG.
Introducing 3D sub-micrometer technologies based on polymers opened new possibilities of design and fabrication of photonic devices and components in 3D arrangement. 3D laser lithography is direct writing process based on two photon polymerization exhibiting high accuracy and versatility, where numerous resists and even polymer ceramic mixtures can be used. We present design and simulation of polymer based photonic components with a focus on arrayed waveguide gratings (AWG) based on optical multiplexers/demultiplexers and optical splitters. All optical components were designed for 1550 nm operating wavelength, applying two commercial photonics tools. This study creates a basis for the design of optical components in 3D arrangement, which will be fabricated by 3D laser lithography.
During two studies the influence of technologies on sleep were analyzed. The first one is about the effect of light on the circadian rhythm and as a consequence on sleep quality of persons in a vegetative state. The second one, which is still running, surveys the influence of several technologies on the sleep of elderly people living in a nursing home.
Verbraucherseitige Laststeuerung (Demand Side Management – DSM) wird als ein möglicher Ansatz betrachtet, um die Auswirkungen des Ausbaus von fluktuierenden Erneuerbaren im Stromnetz auszugleichen. Sollen viele verteilte Energiesysteme damit angesprochen werden, stellen zentralistische Ansätze dabei hohe Anforderungen an die Kommunikationsinfrastruktur. Als Alternative wird vielfach eine autonome Laststeuerung (ADSM) mit anreizbasierter Optimierung direkt auf dem Verbrauchergerät betrachtet. Dabei kann die Anreizfunktion mittels unidirektionaler Kommunikation übertragen werden.
Am Forschungszentrum Energie der Fachhochschule Vorarlberg wurden in den letzten Jahren Algorithmen und Prototypen für den Einsatz von ADSM auf verschiedensten verteilten Energiespeichern im elektrischen Stromnetz entwickelt. Dabei werden sowohl thermische Energiespeicher (z. B. Haushalts-Warmwasserspeicher) als auch elektrochemische Speicher (z. B. Batteriespeichersysteme oder Elektroautos) betrachtet. Außerdem werden die Auswirkungen solcher Systeme auf das elektrische Verteilnetz untersucht. Dieser Artikel gibt einen Überblick über die entwickelten Methoden und Ergebnisse aus diesem Forschungsfeld mit dem Ziel, ein weitreichendes Verständnis für die Chancen und Grenzen des ADSM zu schaffen.
Background: The development of mobile interventions for noncommunicable diseases has increased in recent years. However, there is a dearth of apps for patients with peripheral arterial disease (PAD), who frequently have an impaired ability to walk.
Objective: Using a patient-centered approach for the development of mobile interventions, we aim to describe the needs and requirements of patients with PAD regarding the overall care situation and the use of mobile interventions to perform supervised exercise therapy (SET).
Methods: A questionnaire survey was conducted in addition to a clinical examination at the vascular outpatient clinic of the West-German Heart and Vascular Center of the University Clinic Essen in Germany. Patients with diagnosed PAD were asked to answer questions on sociodemographic characteristics, PAD-related need for support, satisfaction with their health care situation, smartphone and app use, and requirements for the design of mobile interventions to support SET.
Results: Overall, a need for better support of patients with diagnosed PAD was identified. In total, 59.2% (n=180) expressed their desire for more support for their disease. Patients (n=304) had a mean age of 67 years and half of them (n=157, 51.6%) were smartphone users. We noted an interest in smartphone-supported SET, even for people who did not currently use a smartphone. “Information,” “feedback,” “choosing goals,” and “interaction with physicians and therapists” were rated the most relevant components of a potential app.
Conclusions: A need for the support of patients with PAD was determined. This was particularly evident with regard to disease literacy and the performance of SET. Based on a detailed description of patient characteristics, proposals for the design of mobile interventions adapted to the needs and requirements of patients can be derived.
In this paper, low-loss Y-branch splitters up to 128 splitting ratio are designed, simulated, and optimized by using 2D beam propagation method in OptiBPM tool by Optiwave. For an optical waveguide, a silica-on-silicon material platform is used. The splitters were designed as a planar structure for a telecommunication operating wavelength of 1.55 m. According to the minimum insertion loss and minimum non-uniformity, the optimum length for each Y-branch is determined. The influence of the pre-defined S-Bend waveguide shapes (Arc, Cosine, Sine) and of the waveguide core size reduction on the splitter performance has been also studied. The obtained simulation results of all designed splitters with different S-Bend shape waveguides together with the different waveguide core sizes are discussed and compared with each other.
In this paper, we propose and simulate a new type of three-dimensional (3D) optical splitter based on multimode interference (MMI) for the wavelength of 1550 nm. The splitter was proposed on the square basis with the width of 20 x 20 µm2 using the IP-Dip polymer as a standard material for 3D laser lithography. We present the optical field distribution in the proposed MMI splitter and its integration possibility on optical fiber. The design is aimed to the possible fabrication process using the 3D laser lithography for forthcoming experiments.
With the digitalisation, and the increased connectivity between manufacturing systems emerging in this context, manufacturing is shifting towards decentralised, distributed concepts. Still, for manufacturing scenarios manual input or augmentation of data is required at system boundaries. Especially in distributed manufacturing environments, like Cloud Manufacturing (CMfg) systems, constant changes to the available manufacturing resources and products pose challenges for establishing connections between them. We propose a feature-oriented representation of concepts, especially from the manufacturing domain, which serves as the basis for (semi-) automatically linking, e.g., manufacturing resources and products. This linking methodologies, as well as knowledge inferred using it, is then used to support distributed manufacturing, especially in CMfg environments, and enhance product development. The concepts and methodologies are to be evaluated in a real world learning factory.