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21.
Direct Observation of Localized Radial Oxygen Migration in Functioning Tantalum Oxide Memristors
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22.
Jukka Vahlo Johanna K Kaakinen Suvi K. Holm Aki Koponen 《Journal of Computer-Mediated Communication》2017,22(2):88-103
In this study, we examine digital game preferences by identifying game dynamics, i.e. player–game interaction modes, of 700 contemporary digital games, and players' (N = 1717) desire to play games with specific types of dynamics. Based on statistical analysis of the data, 5 game dynamics preference categories (“assault,” “manage,” “journey,” “care,” and “coordinate”) and 7 player types were revealed. The results show that identifying player types requires including both preferred and undesired game dynamics categories in the analysis. The findings unveil digital gaming as a more multifaceted phenomenon than common stereotypes suggest. The original game preferences model we present in this study can be conceptualized as a complementary approach for motivations to play and player behavior studies. 相似文献
23.
We generalize an inference algorithm by Angluin, that learns a regular string
language from a "minimally adequate teacher", to regular tree languages. The
(deterministic bottom-up) finite tree automaton constructed by the learning
algorithm is the minimal partial one recognizing the unknown language. This
improves a similar algorithm proposed by Sakakibara by avoiding dead states both in
the resulting automaton and the learning phase, which also leads to a considerable
improvement with respect to efficiency. 相似文献
24.
Johanna Senatore Stéphane Segonds Walter Rubio Gilles Dessein 《Computer aided design》2012,44(12):1151-1160
Computer-Aided Manufacturing (CAM) occupies an increasingly important role in engineering with all it has to offer in terms of new possibilities and improving designer/manufacturer productivity. The present study addresses machining of free-form surfaces on a 3-axis NC machine tool. There have recently been a large number of studies devoted to planning tool paths on free-form surfaces with various strategies being adopted. These strategies are intended to increase efficiency by reducing the overall length of machining. Often, the choice of the cutter is arbitrary and the work focuses on planning. In order to boost productivity, the present work offers assistance in choosing the cutting tool, the machining direction and cutting by surface zones, adopting a milling strategy by parallel planes. To do so, a comparison is made between milling using a spherical end milling cutter and a torus end milling cutter with the same outer radius. This comparison relates to the radius of curvature of the trace left by the cutter at the point of contact between the tool and the workpiece in relation to the direction of feed motion. 相似文献
25.
Johanna Suomi Jukka Ranta Pirkko Tuominen Tiina Putkonen Christina Bäckman Marja-Leena Ovaskainen 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(1):41-53
Nitrite intake from the consumption of cured meat and tap water was estimated for Finnish children of 1, 3 and 6 years as well as Finnish adults of 25–74 years. Nitrite content in the foods was measured by capillary electrophoresis, and was then used together with individual food consumption data from the FINDIET 2007 and DIPP studies in a stochastic exposure assessment by a Monte Carlo Risk Assessment (MCRA) program. Nitrite intake from additive sources and tap water was assessed, and more than every 10th child between the ages 3 and 6 years was estimated to have a nitrite intake exceeding the acceptable daily intake (ADI) of nitrite. The high exposure levels were caused by frequent consumption of large portions of sausages, up to 350 g day–1 or 750 g in 3 days, among the children. Median nitrite intake from cured meat was 0.016, 0.040, 0.033 and 0.005 mg kg–1 body weight day–1 for children of 1, 3 and 6 years and adults, respectively. Bayesian estimation was employed to determine safe consumption levels of sausages and cold cuts for children, and these results gave rise to new national food consumption advice. 相似文献
26.
Anat Akiva Johanna Melke Sana Ansari Nalan Liv Robin van der Meijden Merijn van Erp Feihu Zhao Merula Stout Wouter H. Nijhuis Cilia de Heus Claudia Muñiz Ortera Job Fermie Judith Klumperman Keita Ito Nico Sommerdijk Sandra Hofmann 《Advanced functional materials》2021,31(17):2010524
Bone formation (osteogenesis) is a complex process in which cellular differentiation and the generation of a mineralized organic matrix are synchronized to produce a hybrid hierarchical architecture. To study the mechanisms of osteogenesis in health and disease, there is a great need for functional model systems that capture in parallel, both cellular and matrix formation processes. Stem cell-based organoids are promising as functional, self-organizing 3D in vitro models for studying the physiology and pathology of various tissues. However, for human bone, no such functional model system is yet available. This study reports the in vitro differentiation of human bone marrow stromal cells into a functional 3D self-organizing co-culture of osteoblasts and osteocytes, creating an organoid for early stage bone (woven bone) formation. It demonstrates the formation of an organoid where osteocytes are embedded within the collagen matrix that is produced by the osteoblasts and mineralized under biological control. Alike in in vivo osteocytes, the embedded osteocytes show network formation and communication via expression of sclerostin. The current system forms the most complete 3D living in vitro model system to investigate osteogenesis, both in physiological and pathological situations, as well as under the influence of external triggers (mechanical stimulation, drug administration). 相似文献
27.
Uta Klement Johanna Ekberg Simone Creci Stephen T. Kelly 《Journal of Coatings Technology and Research》2018,15(4):753-757
A large variety of coatings are used to protect structural engineering materials from corrosion, wear, and erosion, and to provide thermal insulation. In this work, yttria-stabilized zirconia coatings produced by suspension plasma spraying were investigated with respect to their microstructure and especially their porosity, as the porosity affects the thermal insulation of the underlying component. To determine porosity, pore size distribution, and pore shape, the coatings were investigated using novel advanced characterization techniques like NMR cryoporometry and X-ray microscopy. In general, the porosity is inhomogeneously distributed and the coatings showed a large variety of pore sizes ranging from a few nanometers to micrometers. 相似文献
28.
Lisa Meier-Dinkel Johanna Trautmann Luc Frieden Ernst Tholen Christoph Knorr Ahmad Reza Sharifi Mark Bücking Michael Wicke Daniel Mörlein 《Meat science》2013
This study aimed to assess the influence of two label conditions on the acceptance of boar meat. A central location test was conducted with 145 consumers each assessing 4 pieces of pork loin. 相似文献
29.
Johanna Lilius 《Housing Studies》2014,29(6):843-861
This paper addresses the phenomenon of families returning to inner cities. With evidence from the first qualitative study done on families residing in inner-city Helsinki, it demonstrates that urban living reduces the sharp divide between life before having children and family life. Urban parents stay in the city much for the same reasons they first moved there: because they are attracted to population density, good amenities and good public transport. Living in the city enables a lifestyle where different life stages blend into each other. The paper, however, reveals that there is a lack of understanding among city planners and politicians about family needs in the inner city. By adopting a framework of the reviewed literature, the paper draws on the argument that modernist ideals on proper family living still prevail. The paper suggests that planning must acknowledge that exclusionary life stages are eroding and creating a need to facilitate multiple forms of lifestyles. 相似文献
30.
Raine Mäntysalo Johanna Tuomisaari Kaisa Granqvist Vesa Kanninen 《Planning Theory & Practice》2013,14(4):555-572
ABSTRACTThe city of Lahti, Finland, has developed a unique policy of combining city strategy work with strategic master planning in an iterative process. It thereby offers insights to research on strategic spatial planning, exemplifying how institutional frameworks of statutory planning can be utilized as resources in strategic planning. Three lessons from the Lahti case are drawn: (1) utilize the moments of opportunity in the institutional environment of statutory planning, (2) shift the focus from the level of ‘strategic plans’ to the policy level of strategy work, (3) develop strategic planning as a platform for diverse ‘languages’. 相似文献