Integration of reliable algorithms into modeling software

In this note we discuss strategies that would enhance modern modeling and simulation software (MSS) with reliable routines using validated data types, controlled rounding, algorithmic differentiation and interval equation or initial value problem solver. Several target systems are highlighted. In stochastic traffic modeling, the computation of workload distributions plays a prominent role since they influence the quality of service parameters. INoWaTIV is a workload analysis tool that uses two different techniques: the polynomial factorization approach and the Wiener-Hopf factorization to determine the work-load distributions of GI/GI/1 and SMP/GI/1 service systems accurately. Two extensions of a multibody modeling and simulation software were developed to model kinematic and dynamic properties of multibody systems in a validated way. Furthermore, an interface was created that allows the computation of convex hulls and reliable lower bounds for the distances between subpav-ing-encoded objects constructed with SIVIA (Set Inverter Via Interval Analysis)

A Novel Concept for In-Situ Gas-Phase Laser Raman Spectroscopy for SOFC

Gas-phase laser Raman spectroscopy has recently been adopted to determine the concentrations of relevant gaseous species within the anode flow channel with high spatial and temporal resolution during operation at technically relevant operating conditions. The paper describes the configuration of an optically accessible SOFC, the laser system and optical setup for 1 D Raman spectroscopy as well as the challenges associated with the measurements of an electrolyte supported cell of a size of 50 x 50 mm2. At different operating conditions Raman spectra were recorded and concentration profiles of gas species along the flow path in the anode were determined demonstrating this new experimental approach for a better understanding of SOFC processes

Research of the Power Plant Operational Modes

In this article the algorithm of the power plant operational modes research is offered. According to this algorithm the program for the modes analysis and connection power transformers choice is developed. The program can be used as educational means for studying of the power plant electric part, at the same time basic data are provided. Also the program can be used for the analysis of the working power plants modes. Checks of the entered data completeness and a choice correctness of the operational modes are provided in the program; in all cases of a deviation from the correct decisions to the user the relevant information is given

Validity and psychometric properties of the self-identification as having a mental illness scale (SELF-I) among currently untreated persons with mental health problems

Conceptualizing own symptoms as potential signs of a mental illness is an important, yet underresearched step towards appropriate help. Few validated measures address recognition and identification of own mental illness. Aim of this study is to investigate performance and correlates of the ‘Self-Identification as Having a Mental Illness’ scale (SELF-I) in a group of 229 currently untreated individuals with mental health problems, predominantly depression. Measures included: self-identification with having a mental illness (SELF-I), depressive and somatic symptom severity (PHQ-9 and PHQ-15), illness perceptions (B-IPQ-R-C), and sociodemographic variables. Principal-component analysis revealed in a unidimensional factor structure. The SELFI showed good reliability in terms of internal consistency (Cronbach’s alpha, 0.85-0.87) and retest reliability over three months (Intraclass correlation coefficient, 0.74). Associations with depressive symptoms, previous treatment experiences and self-labelling demonstrated construct and criterion validity. Low associations with somatic symptoms and with illness-perceptions as measured by the B-IPQ-R-C indicated discriminant validity. We did not observe any floor or ceiling effects. The SELF-I scale is a brief, unidimensional and reliable measure of selfidentification as having a mental illness that offers useful research perspectives

International Veterinary Epilepsy Task Force recommendations for systematic sampling and processing of brains from epileptic dogs and cats

Traditionally, histological investigations of the epileptic brain are required to identify epileptogenic brain lesions, to evaluate the impact of seizure activity, to search for mechanisms of drug-resistance and to look for comorbidities. For many instances, however, neuropathological studies fail to add substantial data on patients with complete clinical work-up. This may be due to sparse training in epilepsy pathology and or due to lack of neuropathological guidelines for companion animals. The protocols introduced herein shall facilitate systematic sampling and processing of epileptic brains and therefore increase the efficacy, reliability and reproducibility of morphological studies in animals suffering from seizures. Brain dissection protocols of two neuropathological centres with research focus in epilepsy have been optimised with regards to their diagnostic yield and accuracy, their practicability and their feasibility concerning clinical research requirements. The recommended guidelines allow for easy, standardised and ubiquitous collection of brain regions, relevant for seizure generation. Tissues harvested the prescribed way will increase the diagnostic efficacy and provide reliable material for scientific investigations

A Novel Concept for In-Situ Gas-Phase Laser Raman Spectroscopy for SOFC

Gas-phase laser Raman spectroscopy has recently been adopted to determine the concentrations of relevant gaseous species within the anode flow channel with high spatial and temporal resolution during operation at technically relevant operating conditions. The paper describes the configuration of an optically accessible SOFC, the laser system and optical setup for 1 D Raman spectroscopy as well as the challenges associated with the measurements of an electrolyte supported cell of a size of 50 x 50 mm2. At different operating conditions Raman spectra were recorded and concentration profiles of gas species along the flow path in the anode were determined demonstrating this new experimental approach for a better understanding of SOFC processes

In situ Laser Raman Spectroscopy for Investigating SOFC Processes

The application of advanced diagnostic methods for monitoring cell characteristics of solid oxide fuel cells (SOFC) under real operating conditions can provide detailed information about the spatial distribution of cell properties in order to increase the fundamental understanding and to optimize the operational behavior. At high fuel utilization which is required for achieving high efficiency, strong concentration gradients of the fuel gas can occur which might detrimentally affect both performance and durability. To study inhomogeneous distributions of electrochemical and thermal cell properties during operation, DLR has developed spatially resolved diagnostic techniques such as segmented cell technology that allows for the determination of local current density and voltage, local impedance data, temperature distribution and local gas concentrations. To complement the existing diagnostic techniques, gas-phase laser Raman spectroscopy has recently been adopted to determine the concentrations of relevant gaseous species within the anode flow channel with high spatial and temporal resolution during operation at technically relevant operating conditions. A test rig has been built up which gives an optical access to the flow field of a SOFC cell setup through transparent windows in the furnace and using a transparent anode flow field entirely consisting of quartz glass. The Raman experiments were performed by means of a laser system using three double-pulse Nd:YAG lasers. The paper describes the experimental setup of gas-phase Raman spectroscopy measurements with an operating electrolyte-supported SOFC cell of a size of 50x50 mm2. At varying operating conditions with different fuel gas compositions, electrical loads and operating temperatures, Raman spectra were recorded and concentration profiles of gas species along the flow path in the anode were determined. The results obtained from Raman spectroscopy measurements are correlated with results from electrochemical characterization methods such as i-V characteristics and electrochemical impedance spectroscopy

Structural and Electronic Flexibility in Hydrides of Zintl Phases with Tetrel–Hydrogen and Tetrel–Tetrel Bonds

The hydrogenation of Zintl phases enables the formation of new structural entities with main group elementhydrogen bonds in the solid state. The hydrogenation of SrSi, BaSi and BaGe yields the hydrides SrSiH5/3-x, BaSiH5/3-x and BaGeH5/3-x. The crystal structures show a six-fold superstructure compared to the parent Zintl phase and were solved by a combination of X-ray, neutron and electron diffraction and the aid of DFT calculations. Layers of connected HSr4 (HBa4) tetrahedra containing hydride ions alternate with layers of infinite single- and double-chain polyanions, where hydrogen atoms are covalently bound to silicon and germanium. The idealized formulae AeTtH5/3 (Ae = alkaline earth, Tt = tetrel) can be rationalized with the Zintl-Klemm concept according to (Ae2+)3(TtH-)(Tt2H2-)(H-)3, where all Tt atoms are three-binding. The non-stoichiometry (SrSiH5/3-x, x = 0.17(2); BaGeH5/3-x, x = 0.10(3)) can be explained by additional π-bonding of the Tt chains