Bielefeld, Germany
Bielefeld, Germany

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Schulz M.,FH Bielefeld | Gray R.,University of the West of England | Abderhalden C.,University of Bern | Behrens J.,Martin Luther University of Halle Wittenberg
Schizophrenia Research | Year: 2013

Background: Non-adherence with antipsychotic medication is common in patients with schizophrenia. Aims: To establish the efficacy of adherence therapy (AT) compared to treatment as usual (TAU) in improving medication compliance in patients following an acute episode of schizophrenia. Method: The study was designed as a parallel group, single blind, randomised controlled trial. Fieldwork was conducted in four centres (3 in Germany and 1 in Switzerland) and involved a total of 161 patients. Patients received 8 sessions of AT in addition to treatment as usual. The main outcomes of this study were adherence and psychopathology at 12. weeks post discharge follow up. Results: In total 80 patients received AT and 57 TAU. Intention-to-treat analysis included all randomised patients. Psychopathology, as determined using the PANSS-total, improved in the AT compared to TAU group by a mean of - 6.16 points 12. weeks after discharge from hospital (p < .05). AT had no significant effects on patients' adherence, treatment attitudes or functioning. No significant adverse events were reported. Conclusion: AT improves psychopathology in patients recovering from an acute episode of schizophrenia. © 2013 Elsevier B.V.

Fischer W.,FH Bielefeld
Frontiers of Physics in China | Year: 2011

The diffusive scaling is studied based on pomeron loop equations in the fixed coupling case. At Y ≫ YDS, the gluon number fluctuations become important, the geometric scaling is replaced by the diffusive scaling. In the diffusive scaling regime, the deep inelastic scattering (DIS) total scattering cross-section is a function of single variable [1/(r2Qs2(x))]/√DY. We show that the deep inelastic scattering experimental data lie on a single curve, which seems to indicate the existence of the diffusive scaling phenomenology in the deep inelastic scattering. © 2011 Higher Education Press and Springer-Verlag Berlin Heidelberg.

Petrova S.I.,FH Bielefeld
Materials Research Society Symposium Proceedings | Year: 2013

We consider the modeling and simulation of multiscale phenomena which arise in finding the optimal shape design of microcellular composite materials with heterogeneous microstructures. The paper focuses on the solution of the resulting partial differential equation (PDE) constrained structural optimization problem and development of efficient multiscale numerical algorithms which are challenging tools in reducing the computational complexity. The modeling strategy is applied in materials science for microstructural ceramic materials of multiple constituents. Our multiscale method is based on the efficient combination of both macroscopic and microscopic models. The homogenization technique based on the concept of strong separation of scales and the asymptotic expansion of the unknown displacements is applied to extract the macroscopic information from the microscale model. In the framework of all-at-once approach we find a proper combination of the iterative procedure for the nonlinear problem arising from the first order necessary optimality conditions, also known as Karush-Kuhn-Tucker (KKT) conditions, and efficient large-scale solvers for the stress-strain constitutive equation. We use the path-following predictor-corrector schemes by means of Newton's method and fast multigrid (MG) solution techniques. The performance of two preconditioners, incomplete Cholesky (IC) and algebraic multigrid (AMG), for the resulting homogenized state equation is studied. The comparative analysis for both preconditioners in terms of number of iterations and computing times is presented and discussed. Our interests focus on the parallel implementation of the preconditioning techniques and the use of BoomerAMG as a part of the free software library Hypre developed at the Center for Applied Scientific Computing (CASC), Lawrence Livermore National Laboratory (LLNL). © 2013 Materials Research Society.

Hamelmann F.U.,FH Bielefeld
Journal of Physics: Conference Series | Year: 2014

This paper show results from the development of transparent conductive oxides (TCO's) on large areas for the use as front electrode in thin film silicon solar modules. It is focused on two types of zinc oxide, which are cheap to produce and scalable to a substrate size up to 6 m2. Low pressure CVD with temperatures below 200°C can be used for the deposition of boron doped ZnO with a native surface texture for good light scattering, while sputtered aluminum doped ZnO needs a post deposition treatment in an acid bath for a rough surface. The paper presents optical and electrical characterization of large area samples, and also results about long term stability of the ZnO samples with respect to the so called TCO corrosion.

Weicht J.A.,FH Bielefeld | Hamelmann F.U.,FH Bielefeld | Behrens G.,FH Bielefeld
Journal of Physics: Conference Series | Year: 2014

For analyzing the long-term behavior of thin film a-Si/μc-Si photovoltaic modules, it is important to observe the light-induced degradation (LID) in dependence of the temperature for the parameters of the one-diode model for solar cells. According to the IEC 61646 standard, the impact of LID on module parameters of these thin film cells is determined at a constant temperature of 50°C with an irradiation of 1000 W/m2 at open circuit conditions. Previous papers examined the LID of thin film a-Si cells with different temperatures and some others are about a-Si/μc-Si. In these previous papers not all parameters of the one-diode model are examined. We observed the serial resistance (Rs), parallel resistance (Rp), short circuit current (Isc), open circuit voltage (Uoc), the maximum power point (MPP: Umpp, Impp and Pmpp) and the diode factor (n). Since the main reason for the LID of silicon-based thin films is the Staebler Wronski effect in the a-Si part of the cell, the temperature dependence of the healing of defects for all parameters of the one-diode model is also taken into account. We are also measuring modules with different kind of transparent conductive oxides: In a-Si thin film solar cells fluorine-doped tin oxide (FTO) is used and for thin film solar cells of a-Si/μc-Si boron- doped zinc oxide is used. In our work we describe an approach for transferring the parameters of a one-diode model for tandem thin film solar cells into the one-diode model for each part of the solar cell. The measurement of degradation and regeneration at higher temperatures is the necessary base for optimization of the different silicon-based thin films in warm hot climate.

Pomaska G.,FH Bielefeld
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives | Year: 2013

Mindener Museum's Lapidarium incorporates a collection of stone work like reliefs, sculptures and inscriptions from different time epochs as advices of the city's history. These gems must be protected against environmental influences and deterioration. In advance of the measures a 3D reconstruction and detailed documentation has to be taken. The framework to establish hard- and software must match the museum's infrastructure. Two major question will be answered. Are low-cost scanning devices like depth cameras and digital of the shelf cameras suitable for the data acquisition? Does the functionality of open source and freeware covers the demand on investigation and analysis in this application? The working chain described in this contribution covers the structure from motion method and the reconstruction with RGB-D cameras. Mesh processing such as cleaning, smoothing, poisson surface reconstruction and texturing will be accomplished with MeshLab. Data acquisition and modelling continues in structure analysis. Therefore the focus lies as well on latest software developments related to 3D printing technologies. Repairing and finishing of meshes is a task for MeshMixer. Netfabb as a tool for positioning, dimensioning and slicing enables virtual handling of the items. On the Sketchfab web site one can publish and share 3D objects with integration into web pages supported by WebGL. Finally if a prototype is needed, the mesh can be uploaded to a 3D printing device provided by an online service.

Pross S.,FH Bielefeld
Journal of integrative bioinformatics | Year: 2011

Biological systems are often very complex so that an appropriate formalism is needed for modeling their behavior. Hybrid Petri Nets, consisting of time-discrete Petri Net elements as well as continuous ones, have proven to be ideal for this task. Therefore, a new Petri Net library was implemented based on the object-oriented modeling language Modelica which allows the modeling of discrete, stochastic and continuous Petri Net elements by differential, algebraic and discrete equations. An appropriate Modelica-tool performs the hybrid simulation with discrete events and the solution of continuous differential equations. A special sub-library contains so-called wrappers for specific reactions to simplify the modeling process. The Modelica-models can be connected to Simulink-models for parameter optimization, sensitivity analysis and stochastic simulation in Matlab. The present paper illustrates the implementation of the Petri Net component models, their usage within the modeling process and the coupling between the Modelica-tool Dymola and Matlab/Simulink. The application is demonstrated by modeling the metabolism of Chinese Hamster Ovary Cells.

Thiels C.,FH Bielefeld
British Journal of Psychiatry | Year: 2013

In mid-19th-century Germany the conviction that 'mental disease is brain disease' was accompanied by a call for social reform in psychiatry. During neurology training, future psychiatrists often encounter patients with mental disorders rarely seen in psychiatric departments and learn how to avoid misdiagnosing brain diseases as mental disorders.

Tamm U.,FH Bielefeld
2014 Information Theory and Applications Workshop, ITA 2014 - Conference Proceedings | Year: 2014

The Lambert W function fulfills W(y)· eW(y) = y. With the choice y = log (x) it can hence be applied to invert the function f (x) = x · log(x), which is of some interest in the problems discussed. Further applications of the Lambert W function in information theory are briefly surveyed. © 2014 IEEE.

Tamm U.,FH Bielefeld
2015 Information Theory and Applications Workshop, ITA 2015 - Conference Proceedings | Year: 2015

Integer codes correcting a single error in the maximum metric are considered. This corresponds to a packing of tori by cubes. For an asymmetric error of size one these cubes have side length 2 and the problem can be shown to be equivalent to finding zero-error codes for cycles in the sense of Shannon and Lovasz. For side length greater 3 the equivalence of single error correcting integer codes and zero-error codes does not hold any more. © 2015 IEEE.

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