Integrated assessment of global climate change with learning-by-doing and energy-related research and development

This paper presents a small-scale version of an Integrated Assessment Model (IAM) of global climate change, which is based on a global, regionally differentiated computable general equilibrium (CGE) model with endogenous technological change. This model can be viewed as a basic framework for analyzing a broad range of economic issues related to climate change, in particular since technological change is represented in two ways: on the one hand, there is learning-by-doing (LbD) in non-fossil energy supply technologies, and on the other hand there is research and development (R&D)-driven energy-saving technical progress in production. Computational experiments are added for illustrating the role of technological innovation in a world both with and without cooperation in the solution of the global climate problem.     

A magnetic acceleration plasma facility for plasma shock peening

Set-up, function and application potential of pulsed magnetoplasmadynamic self-field accelerators are described. The focus is on the facility MAX (Magnetoplasmadynamic Accelerator-eXperiment). Here, a high power coaxial accelerator is investigated regarding space propulsion and processes aiming for metal treatment as potential applications.A certain amount of gas is accelerated via magnetic fields while the overall kinetic energy of the plasma has to be maximized. During plasma generation numerous parasitic effects are associated with the discharge of the device. Hence, the characterization of the facility in terms of power balance, functional behaviour and kinetic energy of the plasma is mandatory. The kinetic energy is of importance for both space propulsion and the mentioned plasma material treatment processes. Electrodynamic properties enabling the simulation with a snowplow model have been determined experimentally. The model provides a relation between the plasma movement and the electrodynamic properties. Results of the model are current and voltage histories but also statements on the kinetic energy of the plasma. Based on this calorimeters were designed, manufactured and integrated using adequate measurement technology, e.g. fast thermocouples and an infrared camera allowing for the determination of the temporal and spatial temperature histories on the calorimeters. A thermal analysis model was developed and applied to the calorimeter and compared with the measurements. Hence, the thermal energy could be determined which consequently led to an efficiency of 12% for a load voltage of 12 kV and an ambient pressure of 10⁻⁵ mbar.     

Conducting Flame-Sprayed Al Coatings on Textile Fabrics

Electrical conductive and flexible flame-sprayed Al coatings using powder and wire as raw material were successfully deposited onto diverse textile fabrics. The influences of the raw materials, spraying parameters, and fabric materials on the electrical conductivity and microstructure of the metal-fabric composites were investigated. A first series of experiments showed that a coating quantity higher than 20 mg/cm² is necessary for a very good surface conductivity. After the optimization of the spraying parameters, such as a reduced standoff distance and the use of a cooling setup, a high surface conductivity (∼500 S _A) was obtained, which is attributed to a better melting of the spray particles. The improvement in conductivity enables a reduction of the coating quantity, and therefore, the flexibility of the fabric materials is better conserved. This study showed that optimized electrically conductive composites onto flexible fabrics can be produced, without any preliminary thermal or chemical fabric specifications.     

The Chemistry of Intrinsically Chiral Surfaces

Intrinsically chiral metal and mineral surfaces show enantioselective behaviour without modifiers. Examples are artificial high-Miller-index surfaces of metal single crystals with cubic bulk lattice symmetry, which have no mirror planes and are therefore chiral, or surfaces of naturally occurring crystallites of some common minerals, such as α-quartz or calcite. Recent findings with regards to the surface geometry, reactivity and thermal stability of intrinsically chiral surfaces are discussed. A number of enantioselective effects have been reported in connection with the adsorption of small chiral molecules (e.g. alanine, cysteine) on intrinsically chiral surfaces under well-defined conditions. From a combination of experimental surface science techniques and theoretical ab initio model calculations it emerges that these effects are due to a combination of attractive and repulsive adsorbate-substrate and inter–adsorbate interactions.     

Composite Device Computing Environment: A Framework for Situated Interaction Using Small Screen Devices

Contemporary small screen devices are used as personal companion or communication devices. However, their physical dimensions constrain the processing, communication and user interface capabilities. Thus, rich content presentation and diverse service access via small screen appliances is limited accordingly. This paper introduces the Composite Device Computing Environment (CDCE) that provides a framework for dynamically detecting and utilising surrounding computing resources to overcome the small screen device limitations. CDCE includes the communication infrastructure in addition to supporting alternative models for interactivity between small screen clients and surrounding computing resources.     

Foundations of program management: A bibliometric view

Are programs just scale-ups of projects, or do they represent something unique? Recent articles stress the difference of project and program management, but do neither show consensus nor precise definitions of program management. Our comparative bibliometric study of 517 program articles and 1164 project articles published in the last 21 years in leading scientific business journals identifies similarities and differences in theoretical foundations, indicated by the sources cited, and themes, indicated by the keywords. We show that programs have several theoretical bases, such as organizational theories, strategy, product development, manufacturing and change. Programs take an open system view and seek change in permanent organizations. Projects, in turn, have product development as the dominant theory basis. We elaborate eleven distinctive characteristics of program and project management research. Our study proposes themes upon which future theories and empirical studies of programs can be established.     

A monogenetic algorithm for optimal design of large-scale heat exchanger networks

The optimal design of large-scale heat exchanger networks is a quite difficult task not only due to its non-linear characteristics but also due to a great number of local optima in its solution space. An explicit analytical solution of stream temperatures for the superstructure heat exchanger networks was developed, which reduces number of decision variables significantly. Based on this solution, a mathematical model for synthesis of heat exchanger networks was formulated for searching the optimal configuration of a heat recovery system by a hybrid genetic algorithm. For large-scale heat exchanger networks, a monogenetic algorithm based on the optimization of sub-networks is proposed. In the first step of the optimization, the hybrid genetic algorithm is applied to the synthesis of the whole heat exchanger network for finding the functional groups (sub-networks) rather than the chromosomes (positions of the heat exchangers and splits of the streams) and genes (areas and heat capacity flow rates). Then the monogenetic algorithm for evolution of the functional groups is carried out to improve the HEN. This procedure was applied to examples taken from literature and better results were obtained.     

Guest Editorial: Special Issue on Computing Frontiers

Journal of Signal Processing Systems -