Patient centricity in IS healthcare – a framework proposing enablement, empowerment, and engagement of patients as individual IS users

The core of medicine and care is assisting patients with their health- related problems achieving the best results possible. Yet, recent Information Systems (IS) literature describes patient centered IS healthcare as “supporting assistants with IS”. In need of the patient in the center of the digital transformation process in healthcare, we focus our study on examining the IS scientific community’s contribution to digital healthcare regarding patients in the digital transformation process. We conducted an explorative, systematic but selective review of journal articles published in the best Senior Scholar Journals of the Association of Information Systems. Our results reveal a) a framework for digital health research in IS indicating underrepresented research directions, and b) three propositions on patient centricity in IS healthcare focusing on patient enablement, empowerment, and engagement as central streams

Future information and assistance systems for train drivers and evaluation of their usability

Even though train protection systems are used to avoid critical situations, the train driver remains responsible for the continuous monitoring of signal aspects and derivation of suitable actions. This requirement persists, although the position of signals shifts more and more from external signals to in-cab displays, especially with advanced levels of train protection and automatic train control. Errors in the detection and interpretation of signal- or display information and driver distraction may lead to severe accidents. Aim of our research at the Institute of Transportation Systems (ITS) is to develop innovative concepts of the train driver’s workplace in order to secure a safe and efficient railway system that keeps the driver ‘in the loop’. Therefore, we follow a user centred approach. The train driver participates directly in the development and evaluation process of new systems supporting the work in the driver’s cabin. Using our driver’s cabin simulator recently built at the ITS as a flexible vehicle platform in a simulation environment, we are able to investigate the driving behaviour and the train driver’s information processing during his or her task. From the results, we derive concepts in order to optimize the presentation of necessary information and give recommendations how to assist the train driver. In the present paper, first concepts for supporting the train driver in keeping attention and also our simulation environment and the methodology used are described

Development and characterization of adjustable refractive index scattering epoxy acrylate polymer layers

Several polymer films for improved optical properties in optoelectronic devices are presented. In such optical applications, it is sometimes important to have a film with an adjusted refractive index, scattering properties, and a low surface roughness. These diffusing films can be used to increase the efficiency of optoelectronic components, such as organic light-emitting diodes. Three different epoxy acrylate mixtures containing Syntholux 291 EA, bisphenol A glycerolate dimethacrylate, and Sartomer SR 348 L are characterized and optimized with different additives. The adjustable refractive index of the material is achieved by chemical doping using 9-vinylcarbazole.Titanium nanoparticles in the mixtures generate light scattering and increase the refractive index additionally. A high-power stirrer is used to mix and disperse all chemical ubstances together to a homogenousmixture. The viscosity behavior of the mixtures is an important property for the selection of the production method and, therefore, the viscosity measurement results are presented. After the mixing, the monomer mixture is applied on glass substrates by screen printing. To initiate polymerization, the produced films are irradiated for 10 min with ultraviolet radiation and heat. Transmission measurements of the polymer matrix and roughness measurements complement the characterization

Misled by Betz and unsteady flow – review on turbine arrays falsely deemed ‘optimal’

A turbine array is an adjustable flow resistance R placed in a tidal channel. Ideally, it is designed and operated to maximise energy yield. Garrett & Cummins (2005), using optimal control theory applied to the RCelement channel (R) and basin (C), showed: the energy extraction from the flow P_T + P_D is maximised when the flow rate is slowed down by a factor of 1/√3. This result is independent of the ratio of the extracted mechanical power P_T to the total power extraction including the power loss P_D due to the mixing of the bypass flows within the turbine field. The optimisation task for turbine arrays is maximising P_T. This objective raises two questions: ”What is the maximum power P_T that can be extracted, and what is the optimal design (size, topology) and operation to achieve this output?” When addressing them, the literature still uses the Betz ‘limit’ as a reference. The work presented highlights two major problems. First, the Betz ’limit’ is not a constant upper bound for open channel flow. This problem has been discussed and solved by the first author (2011, 2020). Second and more importantly, the presented paper points out the misconception under which several research studies referred to array topologies as ‘optimal’ with regard to design and operation. Hereby, the presented paper contributes to the advancement of tidal power on an axiomatic basis. The misleading by Betz and overvaluing of transient effects is made transparent in a scientific discourse

Misled by Betz and unsteady flow

A turbine array is an adjustable flow resistance R placed in a tidal channel. Ideally, it is designed and operated to maximise energy yield. Garrett & Cummins (2005), using optimal control theory applied to the RCelement channel (R) and basin (C), showed: the energy extraction from the flow PT + PD is maximised when the flow rate is slowed down by a factor of 1/√3. This result is independent of the ratio of the extracted mechanical power PT to the total power extraction including the power loss PD due to the mixing of the bypass flows within the turbine field. The optimisation task for turbine arrays is maximising PT. This objective raises two questions: ”What is the maximum power PT that can be extracted, and what is the optimal design (size, topology) and operation to achieve this output?” When addressing them, the literature still uses the Betz ‘limit’ as a reference. The work presented highlights two major problems. First, the Betz ’limit’ is not a constant upper bound for open channel flow. This problem has been discussed and solved by the first author (2011, 2020). Second and more importantly, the presented paper points out the misconception under which several research studies referred to array topologies as ‘optimal’ with regard to design and operation. Hereby, the presented paper contributes to the advancement of tidal power on an axiomatic basis. The misleading by Betz and overvaluing of transient effects is made transparent in a scientific discourse

Illumination angle and layer thickness influence on the photo current generation in organic solar cells: A combined simulative and experimental study

In most future organic photovoltaic applications, such as fixed roof installations, facade or clothing integration, the solar cells will face the sun under varying angles. By a combined simulative and experimental study, we investigate the mutual interdependencies of the angle of light incidence, the absorber layer thickness and the photon harvesting efficiency within a typical organic photovoltaic device. For thin absorber layers, we find a steady decrease of the effective photocurrent towards increasing angles. For 90-140 nm thick absorber layers, however, we observe an effective photocurrent enhancement, exhibiting a maximum yield at angles of incidence of about 50°. Both effects mainly originate from the angle-dependent spatial broadening of the optical interference pattern inside the solar cell and a shift of the absorption maximum away from the metal electrode

In2_{2}O3_{3}:H-Based Hole-Transport-Layer-Free Tin/Lead Perovskite Solar Cells for Efficient Four-Terminal All-Perovskite Tandem Solar Cells

Narrow-band gap (NBG) Sn–Pb perovskites with band gaps of ∼1.2 eV, which correspond to a broad photon absorption range up to ∼1033 nm, are highly promising candidates for bottom solar cells in all-perovskite tandem photovoltaics. To exploit their potential, avoiding optical losses in the top layer stacks of the tandem configuration is essential. This study addresses this challenge in two ways (1) removing the hole-transport layer (HTL) and (2) implementing highly transparent hydrogen-doped indium oxide In2O3:H (IO:H) electrodes instead of the commonly used indium tin oxide (ITO). Removing HTL reduces parasitic absorption loss in shorter wavelengths without compromising the photovoltaic performance. IO:H, with an ultra-low near-infrared optical loss and a high charge carrier mobility, results in a remarkable increase in the photocurrent of the semitransparent top and (HTL-free) NBG bottom perovskite solar cells when substituted for ITO. As a result, an IO:H-based four-terminal all-perovskite tandem solar cell (4T all-PTSCs) with a power conversion efficiency (PCE) as high as 24.8% is demonstrated, outperforming ITO-based 4T all-PTSCs with PCE up to 23.3%

Optimization of SnO2_{2} electron transport layer for efficient planar perovskite solar cells with very low hysteresis†

Nanostructured tin oxide (SnO$_{2}$) is a very promising electron transport layer (ETL) for perovskite solar cells (PSCs) that allows low-temperature processing in the planar n–i–p architecture. However, minimizing current–voltage (J–V) hysteresis and optimizing charge extraction for PSCs in this architecture remains a challenge. In response to this, we study and optimize different types of single- and bilayer SnO$_{2}$ ETLs. Detailed characterization of the optoelectronic properties reveals that a bilayer ETL composed of lithium (Li)-doped compact SnO$_{2}$ (c(Li)-SnO$_{2}$) at the bottom and potassium-capped SnO$_{2}$ nanoparticle layers (NP-SnO$_{2}$) at the top enhances the electron extraction and charge transport properties of PSCs and reduces the degree of ion migration. This results in an improved PCE and a strongly reduced J–V hysteresis for PSCs with a bilayer c(Li)-NP-SnO$_{2}$ ETL as compared to reference PSCs with a single-layer or undoped bilayer ETL. The champion PSC with c(Li)-NP-SnO$_{2}$ ETL shows a high stabilized PCE of up to 18.5% compared to 15.7%, 12.5% and 16.3% for PSCs with c-SnO$_{2}$, c(Li)-SnO$_{2}$ and c-NP-SnO$_{2}$ as ETL, respectively