Potentials of precision machining processes for the manufacture of micro forming molds

Molds for micro forming processes require specific functional surfaces to provide optimized tribological condition for forming processes. Such topographies with microscopic dimensions can for instance be generated by lithographical methods. However, a main disadvantage of these processes is their low flexibility, e.g. changing the structures to be generated causes extensive adaptations in the manufacturing process. Therefore, mechanical precision machining processes like micro milling, micro grinding and micro polishing are appropriate processes for the manufacture of micro molds of manifold shapes and with well suited micro topographies.     

Profitability of sparse district heating

The expansion of district heating into areas of low heat densities (heat sparse areas) constitutes a challenge due to the higher distribution costs. The profitability of sparse district heating has been analysed from actual investments in 74 areas with 3227 one-family houses connected to district heating between 2000 and 2004 in Göteborg, Sweden. The profitability was estimated from a probable price model, a typical marginal heat generation cost, and the investments from the actual connections made. The analysis identified factors as the linear heat density and heat sold per house explaining the main variations in profitability. The profitability analysis was concluded with a competition analysis. The main conclusion is that sparse district heating is possible when reaching low investment costs for the local distribution network and low marginal costs for the heat generation. In Sweden, the general competitiveness of sparse district heating is facilitated by the high consumption taxes for fuel oil, natural gas, and electricity. Hence, it should be more difficult to introduce sparse district heating in other countries with low energy taxes.     

On the design of signal sets with constrained magnitude spectrum and phase structure

In this paper, a new method is introduced for designing signals that have low cross‐correlation among them with constant passband magnitude spectrum and quadratic phase. It is shown that in order to get low values of the cross‐correlation magnitude between any two signals in the set, the coefficients of the phase functions should be equally spaced along one axis of an ellipse determined by the bandwidth and time duration of signals. Furthermore, as an estimate of the maximum cross‐correlation magnitude, a new tighter upper bound is also given in the paper. Copyright © 2002 John Wiley & Sons, Ltd.     

Do heavy metals prevent the agricutlural use of municipal sludge?

The chemical binding of heavy metals on different samples of soil was found. It was shown that the distribution between undissolved metals and metals in solution was dependent upon pH, clay-and humus content. Requiring a concentration of metals in soil water corresponding to WHO's standard for drinking water, it was possible to calculate on the basis of the results obtained, how much sludge can be applied per ha. It was shown that lead in most cases is the metal limiting the amount of sludge, which can be used.     

Measurement of adhesion of thin evaporated films on glass substrates by means of the direct pull method

The so-called “direct pull method” is applied to the measurement of adhesion of vacuum-deposited thin film coatings on glass substrates. The results obtained by this method are influenced by errors in alignment of the experimental set-up and by non-uniformities of the cement films used to pull the coatings off the substrate. These effects are analysed. Results are presented for films of zinc sulphide, cryolite and silver deposited on BK7 glass substrates. The forces of adhesion on ion-bombarded substrates in these cases are found to be 430 kp/cm², 540 kp/cm² and 230 kp/cm² respectively.     

Triggering Creativity in Teams: An Exploratory Investigation

Triggering, developing and maintaining creativity in teams is critical to the economic performance of the firm. This article presents an exploratory action research effort in a health care organization that focused on interaction patterns amongst team members, creativity and performance. The results indicate that the teams’ inquiry and dialogue into their interaction patterns have the potential of influencing creativity. Team interaction patterns were found to influence team performance. Directions for future research are discussed.     

Quantifizierung IKS-basierter Marktleistungen

The systematic construction of patterns for an ICT-based value proposition constitutes a common research field in Information Systems and Marketing. The case of mobile data services and mobile commerce is taken as an example to propose a process for developing such patterns. The business model concept is applied as a framework for structuring relevant phenomena of value creation. Originating from the competence of a mobile network operator to semantically describe the usage context of its mobile subscribers, a new value proposition within an advertising-based business model for mobile commerce is derived. This allows advertisers to purchase context information for the sake of a targeted marketing communication within mobile portals. Conjoint analysis as an established marketing method is applied to empirically quantify the originating value for advertisers. It can be demonstrated that advertisers have a willingness to pay and demand for such an advertising-based business model in mobile commerce.     

An ergonomic study on plate shears, applying physical, physiological and psychophysical methods

An ergonomic evaluation model for hand tools was developed and applied in a project aiming at assessment of work with plate shears. Measurement variables were physical, physiological and psychophysical. They included tool force and opening angle, wrist movements, muscular strain and fatigue, subjective rating of symptoms, and localization of symptoms, in a group of male professional platers. Different hand grips were studied in a series of cutting tasks (4.2 m cutting length). Results showed that working with conventional plate shears is extremely physically demanding. The peak force required was in the range of 26 to 72 per cent of the subjects' maximal hand grip force. There was ample localized muscle fatigue in the forearm. Psychophysical and electrophysiological data agreed with respect to aspects of muscular strain and fatigue. Workers' preferences in the short run seemed to focus on productivity rather than on ergonomic quality. There is a need for development of improved tools, based on formulated requirements.     

Incremental model-based estimation using geometric constraints

We present a model-based framework for incremental, adaptive object shape estimation and tracking in monocular image sequences. Parametric structure and motion estimation methods usually assume a fixed class of shape representation (splines, deformable superquadrics, etc.) that is initialized prior to tracking. Since the model shape coverage is fixed a priori, the incremental recovery of structure is decoupled from tracking, thereby limiting both processes in their scope and robustness. In this work, we describe a model-based framework that supports the automatic detection and integration of low-level geometric primitives (lines) incrementally. Such primitives are not explicitly captured in the initial model, but are moving consistently with its image motion. The consistency tests used to identify new structure are based on trinocular constraints between geometric primitives. The method allows not only an increase in the model scope, but also improves tracking accuracy by including the newly recovered features in its state estimation. The formulation is a step toward automatic model building, since it allows both weaker assumptions on the availability of a prior shape representation and on the number of features that would otherwise be necessary for entirely bottom-up reconstruction. We demonstrate the proposed approach on two separate image-based tracking domains, each involving complex 3D object structure and motion.