Cardiovascular and metabolic determinants of quality of life in patients with cancer

AIMS: Maintaining quality of life (QoL) in patients with cancer has gathered significant interest, but little is known about its major determinants. We sought to identify determinants of QoL in patients undergoing cancer treatment as well as in treatment-naïve patients about to commence such therapy. METHODS AND RESULTS: QoL was assessed in 283 patients with cancer using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 questionnaire. All patients underwent a battery of tests including physical examination, resting electrocardiogram, hand grip strength, and biochemistry assessment. Using multivariable logistic regression, we found that age [odds ratio (OR) 0.954, 95% confidence interval (CI) 0.916-0.994], resting heart rate (OR 1.036, 95% CI 1.004-1.068), hand grip strength (OR 0.932, 95% CI 0.878-0.990), and the presence of cachexia (OR 4.334, 95% CI 1.767-10.631) and dyspnoea (OR 3.725, 95% CI 1.540-9.010; all P < 0.05) remained independently predictive of reduced QoL. CONCLUSIONS: Therefore, it may be reasonable to address circumstances that are affecting muscle mass, body weight, and heart rate to maintaining QoL; however, prospective studies to test these endpoints are required

Integrated Design of Mechatronic Components for Controlled Pantographs

In this paper a concept of a integrated design environment is explained to support the development of new pantograph concepts. For improving the dynamic behaviour of the combined pantograph/catenary system control units and active elements are considered in the design process. The introduced environment enables new mechatronic approaches for concepts of the complete system as well as for certain components. Therefore the detailed simulation model of the pantograph is set up directly according to the design data. The control concept is adjusted using a design program for control units. Additionally, a specialized simulation program for catenaries was connected to a standard tool for multibody system analysis. First proposals of mechatronic concepts for certain components of a present high performance pantograph demonstrated the efficiency of the realized CAE-concept

Simulation and Control Design for Mechatronic Pantographs

New pantograph concepts require an integrated development environment for its design process. The set up of dynamic models and the simulation of the interaction between pantographs and catenaries are essential to evaluate enhanced mechatronic design concepts. The introduced simulation environment enables investigations on new approaches for the complete system as well as for single components. For verification tasks, a detailed simulation model of the pantograph was set up directly according its design data. Different control concepts were adjusted using a specialized analysis program for control units. In particular, the co-simulation between a standard MBS and a specific catenary simulation program made a more precise prediction of the dynamic behaviour possible. First proposals of mechatronic concepts for certain components of a present high performance pantograph demonstrated the efficiency of the realized CAE-concept

Coupled Simulation of Multibody Systems and Elastic Structures

The coupled simulation of mutlibody systems (MBS) and elastic structures is an essential method to investigate the interaction between both systems. For example pantograph/catenary systems or the crossing of bridges by trains are typical applications where this simulation method is used intensively. Thereby the equations of motion of the MBS form a differential-algebraic equation which is combined with the partial differential equations describing the elastic structure. Both systems are coupled by geometrical contact conditions that result in additional algebraic equations. If the flexible systems do not fit into the common approach to handle the elastic dermation of bodies in a multibody system the method of finite elements (FEM) or finite differences (FDM) are suitable to discretize the PDE system in space and in time in two separate steps. For the application of the coupled pantograph/catenary equipment, the pantograph system is represented by a multibody model whereas the catenary is a highly elastic structure. Therefore a model of an active high speed pantograph was tested in interaction with a catenary system, based on real assembly data. The results showed the advantage of the simulation considering the catenary in a direct way in relation to simplified approximations of the overhead-line dynamics

Virtuelle Bahnsysteme

Zukunftsweisendes Ziel virtueller Technologien ist die vollständige Konzeption eines Produkts im Rechner (virtuelles Produkt) mit anschließender automatischer Fertigung und Produktbegleitung bis hin zu späteren Entsorgung mit Recycling. Wichtige Teilziele sind beispielsweise, Entwicklungszeiten erheblich zu verkürzen sowie Entwicklungskosten deutlich zu senken. Eine zentrale Frage ist bei allen aktuellen Fahrzeugentwicklungen die Notwendigkeit zur Gewichtsreduktion, insbesondere der Ersatz schwerer, verschleißanfälliger Mechanik durch volle Integration der Elektronik

Methodologies for coupling simulation models and codes in mechatronic system analysis and design

The design and analysis process of mechatronic systems requires a wide range of different engineering methods and tools. The demands on simulation model descriptions and solver functionalities are rising due to the increase of system complexity. A development process can only be carried out in an effective way, if all needed models, methods and codes are linked together to an integrated CAE-environment. In the future, the variety of interfaces and types, from a simple model import/export up to a complex co-simulation, will be further extended by new concepts to combine models and codes. A classification of coupling strategies can help to estimate the effects on simulation performance, functionality and accuracy which is important for the decision of an optimal interface type in case of a specific task