Methodological issues in product evaluation: the influence of testing environment and task scenario

This article examines the utility of two commonly used approaches in the evaluation of interactive consumer products: lab-based testing and single task scenarios. These are compared to two more complex and resource-demanding approaches (field-based testing and dual task scenarios) with regard to the test results they produce. An experiment with N = 80 users was carried out, employing a 2 (laboratory vs. field) by 2 (single task vs. dual task scenario) by 2 (on-product information: present vs. absent) between-subjects design. On-product information (advising users to save water and electricity during kettle usage) represented the intervention, of which the effects on user behaviour were compared under the different experimental conditions. The main finding was that the impact of on-product information on user behaviour was strongest in the lab-based testing environment using a single task scenario (i.e., most economical testing condition), compared to the three other experimental conditions. The work found similar effects for self-report measures. The findings of the study point to the risk that the effects of system redesign on user behaviour may be overestimated if low-fidelity testing approaches are employed. The relevance of these findings for other application areas is also discussed (e.g., design of warnings).     

Hough forests for object detection, tracking, and action recognition

Abstract—The paper introduces Hough forests, which are random forests adapted to perform a generalized Hough transform in an efficient way. Compared to previous Hough-based systems such as implicit shape models, Hough forests improve the performance of the generalized Hough transform for object detection on a categorical level. At the same time, their flexibility permits extensions of the Hough transform to new domains such as object tracking and action recognition. Hough forests can be regarded as task-adapted codebooks of local appearance that allow fast supervised training and fast matching at test time. They achieve high detection accuracy since the entries of such codebooks are optimized to cast Hough votes with small variance and since their efficiency permits dense sampling of local image patches or video cuboids during detection. The efficacy of Hough forests for a set of computer vision tasks is validated through experiments on a large set of publicly available benchmark data sets and comparisons with the state-of-the-art.     

Mapping reactive flow patterns in monolithic nanoporous catalysts

The development of high-efficiency porous catalyst membranes critically depends on our understanding of where the majority of the chemical conversions occur within the porous structure. This requires mapping of chemical reactions and mass transport inside the complex nanoscale architecture of porous catalyst membranes which is a multiscale problem in both the temporal and spatial domains. To address this problem, we developed a multiscale mass transport computational framework based on the lattice Boltzmann method that allows us to account for catalytic reactions at the gas–solid interface by introducing a new boundary condition. In good agreement with experiments, the simulations reveal that most catalytic reactions occur near the gas-flow facing side of the catalyst membrane if chemical reactions are fast compared to mass transport within the porous catalyst membrane.     

An evaluation of timed scenario notations

There is a general consensus on the importance of good Requirements Engineering (RE) for achieving high quality software. The modeling and analysis of requirements have been the main challenges during the development of complex systems. Although semi-formal, scenario driven approaches have raised the awareness and use of requirement engineering techniques, mostly because of their intuitive representation. Scenarios are a well established approach to describe functional requirements, uncovering hidden requirements and trade-offs, as well as validating and verifying requirements.The ability to perform quantitative analysis at the requirements level supports the detection of design errors during the early stages of a software development life cycle, and helps reduce the cost of later redesign activities. In order to achieve this goal, non-functional aspects and in particular time-related aspects have to be incorporated at the software requirement phase. This is essential in order to correctly model and analyze time dependent applications at early stages in system development.The widespread interest in time modeling and analysis techniques provides the major motivation for our paper. The objective of the article is to provide readers with sufficient knowledge about existing timed scenario approaches to guide them in making informed decisions to when and how time aspects can be incorporated in their development process. In order to support this process, we present a comprehensive classification, evaluation and comparison of time-based scenario notations. In order to evaluate these existing notations, we introduce a set of eleven time-related criteria and apply them to categorize and compare forty seven scenario construction approaches.     

How mold inserts influence the replication of metallic microparts produced by electroplating into two-component templates

Multi-component injection molding combined with electroplating, the so-called MSG process, represents a promising process chain to replicate metallic microstructures. MSG is the German acronym of ‘Mehrkomponenten-Spritzgießen und Galvanoformung’, in English ‘Multi-component Injection Molding and Electroplating’. The process is based on the highly accurate reproduction of surface details through injection molding to build a microstructure into a two-component template and electrodeposition of e.g. nickel into this cavity. This electroplated micropart is the replication of the former structure. To study the influence of the mold insert on the accuracy of the molded part and the produced microparts, a test specimen was fabricated and analyzed using a milled mold insert. On the mold insert, three microcoil parts, the components of a microgripper, were micromilled. The effect of the individual process steps on the surface quality and dimensional changes of the final microcoil will be presented. It will also be shown how the quality of the injection molding insert influences the dimensional accuracy of the produced microparts. Finally, potential process improvements will be outlined.     

Quality assurance for micro manufacturing processes and primary-shaped micro components

The development of robust and flexible manufacturing processes represents the major challenge to be overcome by industrially applicable micro production. For robustness and flexibility to be ensured also for micro dimensions, the manufacturing processes need to be controlled and continuously improved by means of a quality assurance system that is fast to respond, matches the requirements of production and is tailored to the micro-specific demands. Up to now, micro manufacturing processes have been characterized by a high degree of variability resulting from an increased number of significant influencing factors. Besides, the tolerance specifications of components with micro structures are in the micro and sub-micrometer range, requiring measuring methods to meet the highest demands in terms of accuracy. For micro manufacturing processes to be controlled on the basis of measured data, the increased significance of measuring uncertainty and measurement variation in relation to the required tolerances is to be taken into consideration. Measured data will always reflect the effect of both manufacturing and measurement variation, which may lead to wrong decisions being taken on the approval or rejection of components if the most rigid tolerance specifications need to be met. Therefore, the focus of this research document, generated as part of the Collaborative Research Center (SFB) 499, has been put on the continuous monitoring, control and separation of manufacturing and measurement variation by means of statistical methods and tools. The two ideas presented and discussed are a novel design for quality control charts and a control loop for the combination of statistical process control and statistical modeling, developed as part of the SFB 499. This article concludes by giving first results regarding the use of statistical tools in the field of micro manufacturing technology.     

Metrological sharp shooting for plasma proteins and peptides: The need for reference materials for accurate measurements in clinical proteomics and in vitro diagnostics to generate reliable results

Reliable study results are necessary for the assessment of discoveries, including those from proteomics. Reliable study results are also crucial to increase the likelihood of making a successful choice of biomarker candidates for verification and subsequent validation studies, a current bottleneck for the transition to in vitro diagnostic (IVD). In this respect, a major need for improvement in proteomics appears to be accuracy of measurements, including both trueness and precision of measurement. Standardization and total quality management systems (TQMS) help to provide accurate measurements and reliable results. Reference materials are an essential part of standardization and TQMS in IVD and are crucial to provide metrological correct measurements and for the overall quality assurance process. In this article we give an overview on how reference materials are defined, prepared and what role they play in standardization and TQMS to support the generation of reliable results. We discuss how proteomics can support the establishment of reference materials and biomarker tests for IVD applications, how current reference materials used in IVD may be beneficially applied in proteomics, and we provide considerations on the establishment of reference materials specific for proteomics. For clarity, we solely focus on reference materials related to serum and plasma.     

计算机辅助测试技术及其应用

计算机辅助测试 (CAT )技术是测量领域的前沿技术。文章阐述了CAT技术的发展对机械参数在线测量的影响。并运用德国的专用测量软件 ,用CAT技术对机械参数进行在线测量的例子 ,介绍了CAT技术的基本原理及其应用     

Improvement of Activity and Thermostability of Agar-Entrapped,Thermophilic, Haloalkaliphilic Amylase AmyD8

An extremophilic amylase from Alkalilimnicola sp. NM-DCM-1 was expressed and purified. The amylase, AmyD8, was extremophilic, with maximal activity at 55 °C, pH 10.5 and 2.4 M NaCl. AmyD8 had a broad substrate utilization spectrum, hydrolyzing branched and linear substrates. AmyD8 was stable and active in nonionic and anionic surfactants. AmyD8 was organic solvent resistant, retaining activity after incubation in benzene, methanol, ethanol and isopropanol. AmyD8 was entrapped in an agar–agar matrix with 89% entrapment yield and no loss in relative activity. Entrapped AmyD8 retained its extremophilic properties. Entrapment enhanced AmyD8’s thermal stability, the half-life of the entrapped enzyme nearly doubled after incubation at 50–65 °C. Entrapped AmyD8 had excellent recyclability, retaining 58% of initial activity after 16 hydrolysis cycles. These extreme properties give AmyD8 great economic feasibility.

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