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101.
Software Quality Journal - Nowadays, systems containing components based on machine learning (ML) methods are becoming more widespread. In order to ensure the intended behavior of a software...  相似文献   
102.
Although several studies have examined the impact of open workspaces, there is still an on-going debate about its advantages and disadvantages. Our paper contributes to this debate by shedding light on three issues: the effect of open workspaces on (1) the flow of communication along and across hierarchical lines; (2) the content of communication; and (3) the specificities of open integrated laboratories. Our findings derive from a longitudinal case in a large pharmaceutical company that has relocated some R&D teams from enclosed to multi-space offices and labs. The relocation has resulted in (a) increased interdisciplinary communication, particularly at lower hierarchical levels, (b) a shift of the location of discussions and the content of conversations and (c) an improved knowledge about expertise distribution.

Practitioner Summary: Communication is essential in knowledge-driven organisations. This article examines the impact of a relocation of R&D employees from enclosed to multi-space offices and labs on communication patterns. We explain how the new environment fosters interdisciplinary communication, shifts the location of discussions and increases the knowledge of expertise distribution.  相似文献   

103.
In order to leverage organizational learning, scholars have already defined but are still discussing the interpretation of two different learning types, exploration and exploitation. Exploring new frontiers across knowledge domains and maintaining the balance with exploiting the existing knowledge is critical for the prosperity of an organization. The spatial dimension of organizational learning considers that proximity of employees has an influence on their learning activities, but from a rather macro perspective without taking workspace design into account. We account for these issues by examining the impact of workspace design on knowledge exploration and exploitation on the micro level at distinct stages along the value chain (i.e., the research, development and project market team unit) of Novartis, a pharmaceutical company. In a longitudinal study, employees of the three cases have been interviewed and observed over the course of three years, before and after workspace redesign. With the change from a cellular to an open workspace, employees become closer and highly visible to each other, which influences knowledge work. As the cases occurred sequentially in time, design principles were derived. The findings suggest that exploitation is supported by workspace design that leads to high proximity inducing faster feedback cycles and first‐hand information. Exploration, however, is supported by workspace design that leads to high visibility triggering more cross‐functional interactions and thereby the variability of knowledge. The later the stage in the research and development process, the higher the need for balanced learning activities. This balance is well reflected in a ‘multi‐space’ workspace consisting of shared meeting areas, quiet zones, central staircases and integrated laboratories and desk areas.  相似文献   
104.
Concentrations of 23 elements (Be, Al, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Pd, Cd, Sn, Pt, Pb) were evaluated in whole blood samples of live harbor seals (Phoca vitulina) from two different locations in the Wadden Sea, the Lorenzenplate in Germany, and the Danish island R?m?. Elemental blood levels were compared to data from literature of seals, other marine mammals and humans. While homeostatically controlled elements showed no differences, concentrations of As, Cr, Mn, Mo, Se, and V were higher than human levels. Furthermore, animals from both locations showed significant geographical differences in whole blood concentrations of Al, Mn, Cu, and Pt. These findings could be explained by differences in feeding areas. The element pattern was not affected by gender. In conclusion, these findings indicate an impact of the environment on biochemical blood parameters of the harbor seals. The significant differences of elements in blood samples of two groups of seals, which were associated with geographical variations of prey support the use of element pattern in blood as tool for investigation of environmental impact on seals.  相似文献   
105.
This study examines the biohydrogenation and utilization of the C20 and C22 polyenoic fatty acids in ruminants. Eicosapentaenoic (20∶5n−3) and docosahexaenoic (22∶6n−3) acids were not biohydrogenated to any significant extent by rumen microorganisms, whereas C18 polyenoic fatty acids were extensively hydrogenated. The feeding of protected fish oil increased the proportion of 20∶5 from 1% to 13–18% and 22∶6 from 2% to 7–9% in serum lipids and there were reductions in the proportion of stearic (18∶0) and linoleic (18∶2) acids. The proportion of 20∶5 in muscle phospholipids (PL) increased from 1.5% to 14.7% and 22∶6 from 1.0% to 4.2%; these acids were not incorporated into muscle or adipose tissue triacylglycerols (TAG). In the total PL of muscle, the incorporated 20∶5 and 22∶6 substituted primarily for oleic (18∶1) and/or linoleic (18∶2) acid, and there was no consistent change in the porportion of arachidonic (20∶4) acid.  相似文献   
106.
The composite anode and cathode of solid oxide fuel cells (SOFC) are modelled as sintered mixtures of electrolyte and electrocatalyst particles. A particle packing is first created numerically by the discrete element method (DEM) from a loose packing of 40 000 spherical, monosized, homogeneously mixed, and randomly positioned particles. Once the microstructure is sintered numerically, the effective electrode conductivity is determined by discretization of the particle packing into a resistance network. Each particle contact is characteristic of a bond resistance that depends on contact geometry and particle properties. The network, which typically consists of 120 000 bond resistances in total, is solved using Kirchhoff's current law. Distributions of local current densities and particle potentials are then performed. We investigate how electrode performance depends on parameters such as electrode composition, thickness, density and intrinsic material conductivities that are temperature dependent. The simulations show that the best electrode performance is obtained for compositions close to the percolation threshold of the electronic conductor. Depending on particle conductivities, the electrode performance is a function of its thickness. Additionally, DEM simulations generate useful microstructural information such as: coordination numbers, triple phase boundary length and percolation thresholds.  相似文献   
107.
Users are the primary source of new techniques, i.e. systematic activities by which a complex task is accomplished. Even though user‐generated techniques are a pervasive phenomenon which can be observed in many different contexts, existing research on user innovation has focused on product and service innovations. We focus on this important area of user innovation by studying four cases in the field of medical devices to analyse the processes by which users generate and diffuse new techniques as well as the interdependencies between user‐generated techniques and subsequent changes to product use and product innovation. Our findings suggest that user innovation in techniques triggers product innovation by users and manufacturers. Therefore, users' contributions to total innovation output are much higher than previously considered. Additionally, the diffusion of techniques differs significantly from the diffusion of new products. It can only be achieved with the involvement of diffusion agents and their interpersonal interaction and joint performance of the technique with possible adopters. As the diffusion of a technique is often a prerequisite for the diffusion of any related product, companies are forced to re‐think their marketing strategies.  相似文献   
108.
109.
Biofilm formation, also known as microfouling, on indwelling medical devices such as catheters or prosthetic joints causes difficult to treat and recurrent infections. It is also the initial step for biocorrosion of surfaces in aquatic environment. An efficient prevention of microfouling is preferable but the development of antibiofilm surfaces is enormously challenging. Therefore, soda-lime, aluminosilicate, and three borosilicate glasses with different TiO2 and ZnO compositions were investigated on their feasibility to prevent biofilm formation by standardized in vitro biofilm assays using different pathogenic bacteria. Furthermore, the biocompatibility of these glasses was evaluated using eukaryotic cell lines end erythrocytes. Only two borosilicate glasses, containing TiO2 and ZnO, showed an increased antibiofilm performance inhibiting biofilm adhesion and formation. The biofilm thickness and area were significantly reduced by over 90?% and characterized by diffuse structures. All tested glass types showed neither cytotoxicity nor hemotoxicity. Therefore, the antibiofilm borosilicate-thin glasses are qualified for surface coatings where biofilms are not desirable such as on medical devices.  相似文献   
110.
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