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101.
Production Rate‐Dependent Key Performance Indicators for a Systematic Design of Biochemical Downstream Processes
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Key performance indicators have become a common tool in bioprocess development, as they allow an objective and independent rating and ranking of process alternatives screened. A disadvantage of all key performance indicators developed so far is their strong focus on costs, which makes them neglect the influence of the production rate on the profit of the process. But, since both production costs and production rate have an equally strong impact, both should be considered when decisions have to be made. Therefore, two new key performance indicators are introduced in this work, one for batch and one for continuous processing. They combine product yield, purity performance, variable manufacturing costs, and production rate to one objective. Thereby, misguided trade‐offs between these four individual measures can be replaced by one key performance indicator. This ensures a systematic development of biochemical downstream processes. 相似文献
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In the course of classical optics manufacturing glass components are in permanent direct contact with aqueous operating materials. Such contact leads to a certain absorption of water and hydrogenous compounds that may induce severe glass defects. In this contribution, absorption of hydrogen and other contaminants during grinding of glass was observed and qualitatively detected via laser‐induced breakdown spectroscopy. It is shown that hydrogen, calcium, magnesium, and carbon are implanted into the glass surface where the contaminant concentration increases over grinding time or contact time of the glass surface with water and the grinding tool, respectively. The contaminants hydrogen, calcium, and magnesium can be attributed to the water used as lubricant. In contrast, carbon most likely originates from wear debris of the used silicon carbide grinding pads. Several possible mechanisms that lead to such surface contamination of glasses during grinding – diffusion, accumulation in micro cracks as well as the formation of hydrated silica – are finally introduced. 相似文献
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Alexander Gredner Christoph Gerhard Stephan Wieneke Kai Schmidt Wolfgang Viol 《材料科学与工程:中英文B版...》2013,(6):346-351
In this work, a novel atmospheric pressure plasma-assisted excimer laser annealing method for increasing the generation efficiency of poly-crystalline silicon from amorphous silicon layers is presented. Here, both the plasma and the laser propagate coaxially in order to generate energetic synergies. The influence of different process gases and plasma discharge modes as well as the working distance were investigated. Depending on the particularly applied plasma, the crystalline area was increased by a factor of approx. 1.1 to 1.9, where the highest efficiency was observed when introducing an argon plasma beam to the annealing process. 相似文献
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Dipl.-Ing. Christoph Triebl Christoph Spijker Harald Raupenstrauch Alexander Jarosik Gerhard Angeli 《BHM Berg- und Hüttenm?nnische Monatshefte》2014,159(7):310-311
For the production of high-quality goods in industrial furnaces using minimal expenditure of energy, optimization of the process parameters is required. One tool for improving the processes economically is the simulation of the furnaces by using Computational Fluid Dynamics (CFD). The pre-heating process of a steel strip in a section of an annealing furnace for surface treatment in a hot-dip galvanizing process was simulated using the commercial CFD software Ansys Fluent 15.0. For combustion, the Equilibrium model is used, turbulence is modeled by the realizable-k-ε model, and radiation is taken into account by using the Discrete Ordinate Method (DOM). 相似文献
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Patient-centered care encourages active involvement of patients in their own treatment and a collaborative perspective on the relationship between patient and practitioner. However, to achieve constructive patient–practitioner collaboration in medical consultations the partakers need to successfully interact across conceptual boundaries that can impede intersubjectivity, i.e., the construction of shared meanings and understandings in communicative activities. We present a synthesis of a user-centered approach to designing interactive technology supporting collaboration in face-to-face consultations related to audiological (hearing) rehabilitation. Specifically, we focus on the case of hearing aid tuning, and on the design and utility assessment of a prototype sound environment simulator intended to support the process by helping the patient and the practitioner build a joint understanding of the individual patient’s hearing problem and perceived effects of treatment actions. We describe an empirical and qualitative investigation that calls specific attention to the multi-dimensional boundaries involved in collocated patient–practitioner interactions, and to the explorative and situated nature of the consultation as a collaborative problem-solving process. Here, various micro-practices play a key role in gradually forming a better understanding of the problem at hand and in identifying appropriate treatment steps. Our findings suggest that patient–practitioner collaboration can benefit from interactive technology, which is sufficiently flexible or open-ended in terms of use to accommodate, or be appropriated, to the immediate needs of the situation. We argue that designing technology with the aim of enhancing existing practices of intersubjectivity, rather than doing away with them, improves the chances of enriching collocated patient–practitioner interaction and reduces risk of obstructing it. The main research contribution is an increased understanding of the medical consultation as an instance of collocated collaborative work and learning, and the challenges and opportunities that lie in co-designing interactive solutions that can help the patient take an active and contributing part in the situation. 相似文献