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51.
The aim of the present study was to replicate the distinction between errors, lapses and violations, and to identify aggressive violations from normal or highway code violations. Furthermore, the relationship of these behaviours with road traffic accidents was examined. A total number of 1126 Finnish drivers completed a questionnaire containing the Driver Behaviour Questionnaire (DBQ) with extended violations scale, and questions regarding background information, such as age, gender and mileage. Also, questions about previous accidents and fines were asked. Factor analysis showed that a four-factor structure seemed more appropriate than the earlier established three-factor structure. The four factors were errors, lapses, speeding violations and interpersonal violations. The two types of violations result from different motives, and seem to be associated with different kinds of affect. Both interpersonal and speeding violations were reported most by young males, which was consistent with earlier findings. Logistic regression analyses indicated that errors predicted active accident involvement after partialling out the effects of demographic variables, whereas interpersonal violations were positively related to involvement in passive accidents. This was presumably due to different reporting tendencies of respondents. Speeding tickets were predicted by speeding and interpersonal violations and lapses and penalties for speeding by both kinds of violations and errors. Penalties for speeding, parking and other offences were predicted by interpersonal violations. The implications of these results are discussed. 相似文献
52.
In this article, canonical and spectrally minimal infinite-dimensional state space realizations for periodic functions are considered. It is shown that the periodic functions having ℓ1 Fourier coefficients are precisely those realizable by a Riesz spectral system (RSS) in which the system operator generates a periodic strongly continuous semigroup and the observation operator is bounded. This realization can easily be converted to a canonical and spectrally minimal form. It is shown how the use of RSS and Cesáro sums of Fourier series allows the construction of a state space realization for a given periodic function merely integrable over its period. Simple finite-dimensional approximations with error bounds are derived for the RSS realization. Regular well-posed linear systems (WPLS) are used to construct a Fuhrmann-type realization for a given periodic function integrable over its period. It is shown that the RSS realizations and WPLS realizations are precisely equally good at coping with the possible ill behavior of a given bounded periodic function integrable over its period, but the WPLS realization is not always spectrally minimal or canonical. 相似文献
53.
Eero Hyvnen Eetu Mkel Mirva Salminen Arttu Valo Kim Viljanen Samppa Saarela Miikka Junnila Suvi Kettula 《Journal of Web Semantics》2005,3(2-3):224
This article presents the semantic portal MuseumFinland for publishing heterogeneous museum collections on the Semantic Web. It is shown how museums with their semantically rich and interrelated collection content can create a large, consolidated semantic collection portal together on the web. By sharing a set of ontologies, it is possible to make collections semantically interoperable, and provide the museum visitors with intelligent content-based search and browsing services to the global collection base. The architecture underlying MuseumFinland separates generic search and browsing services from the underlying application dependent schemas and metadata by a layer of logical rules. As a result, the portal creation framework and software developed has been applied successfully to other domains as well. MuseumFinland got the Semantic Web Challence Award (second prize) in 2004. 相似文献
54.
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56.
Process conditions in X-ray lithography for the fabrication of devices with sub-micron feature sizes
This article describes the fabrication of polymer structures with lateral dimensions in the sub-micron regime using hard X-rays
(λc ≈ 0.4 nm) from the electron storage ring ANKA. Spincoated polymethylmethacrylate (PMMA) grades have been analyzed with respect
to development rates and contrast. The contrast has been determined to be constant over a wide dose regime but rapidly decreases
for dose values below 1 kJ/cm3. Films with a thickness from 2 to 11 μm have been patterned using a high resolution X-ray mask consisting of 2 μm thick gold
absorbers on a suspended 1 μm thick silicon nitride membrane. The fabrication of sub-micron X-ray lithography structures with
feature sizes down to 400 nm is confined by the mechanical parameters of the resist material and the process conditions. Surface
tension after development limits the achievable aspect ratio of isolated pillars and walls, depending on the actual resist
height. PMMA structures have been successfully used as template for electroplating of 1 μm thick gold to demonstrate the fabrication
capability of sub-micron scale metal parts. 相似文献
57.
Adopting diffusion theory and the concept of social value orientation, the effects of personality traits on knowledge sharing in a virtual open content community are investigated. In addition to the main effects of personality, it was hypothesized that intrinsic motivations would moderate the effects on knowledge sharing. A sample of N = 256 active users of Wikipedia provided measures of personality, motivation, and knowledge sharing. Latent regression analyses support the notion that authorship of Wikipedia is associated with higher levels of trendsetting and a prosocial value orientation. Moreover, moderation analyses demonstrate that the effect of the latter is moderated by individual differences in motivations to write. Differences with regard to opinion leadership could not be confirmed. 相似文献
58.
Adam Kłodowski Timo Rantalainen Aki Mikkola Ari Heinonen Harri Sievänen 《Multibody System Dynamics》2011,25(4):395-409
A method for bone strain estimation is examined in this article. The flexibility of a single bone in an otherwise rigid human
skeleton model has been studied previously by various authors. However, in the previous studies, the effect of the flexibility
of multiple bones on the musculoskeletal model behavior was ignored. This study describes a simulation method that can be
used to estimate the bone strains at both tibias and femurs of a 65-year-old Caucasian male subject. The verification of the
method is performed by the comparison of the results with other studies available in literature. The results of the study
show good correlation with the results of previous empirical studies. A damping effect of the flexible bones on the model
is also studied in this paper. 相似文献
59.
Mika Kettunen Adnan S Abu‐Surrah Timo Repo Markku Leskel 《Polymer International》2001,50(11):1223-1227
Synthesis of functional aliphatic polyketones was achieved by co‐ and terpolymerization of the strained exo‐methylenecycloalkane, methylenecyclopropane (MCP), and also the dienes 1,5‐hexadiene, 1,7‐octadiene and 1,6‐heptadien‐4‐ol, with carbon monoxide and propene, using the dicationic palladium(II) phosphine complex [Pd(dppp) (NCCH3)2](BF4)2 (I) (dppp is 1,3‐bis(diphenyl‐phosphino)propane) as the catalyst precursor. The resulting MCP/CO copolymer contains both ring‐opened and cyclic microstructures. Ring‐opening copolymerization yields exo‐methylene functionalized polyketone. In contrast to hexadiene/carbon monoxide copolymer (Hx/CO), no ring structures were observed in the alternating octadiene/carbon monoxide (Oc/CO) and heptadien‐4‐ol/carbon monoxide (Hp‐ol/CO) copolymers. The remaining double bonds were left intact to yield polymers with olefinic functionalities in the side chains. © 2001 Society of Chemical Industry 相似文献
60.
Swarna Rautiainen Timo Laaksonen Raili Koivuniemi 《International journal of molecular sciences》2021,22(19)
Adipose-derived mesenchymal stem/stromal cells (ASCs) are an adult stem cell population able to self-renew and differentiate into numerous cell lineages. ASCs provide a promising future for therapeutic angiogenesis due to their ability to promote blood vessel formation. Specifically, their ability to differentiate into endothelial cells (ECs) and pericyte-like cells and to secrete angiogenesis-promoting growth factors and extracellular vesicles (EVs) makes them an ideal option in cell therapy and in regenerative medicine in conditions including tissue ischemia. In recent angiogenesis research, ASCs have often been co-cultured with an endothelial cell (EC) type in order to form mature vessel-like networks in specific culture conditions. In this review, we introduce co-culture systems and co-transplantation studies between ASCs and ECs. In co-cultures, the cells communicate via direct cell–cell contact or via paracrine signaling. Most often, ASCs are found in the perivascular niche lining the vessels, where they stabilize the vascular structures and express common pericyte surface proteins. In co-cultures, ASCs modulate endothelial cells and induce angiogenesis by promoting tube formation, partly via secretion of EVs. In vivo co-transplantation of ASCs and ECs showed improved formation of functional vessels over a single cell type transplantation. Adipose tissue as a cell source for both mesenchymal stem cells and ECs for co-transplantation serves as a prominent option for therapeutic angiogenesis and blood perfusion in vivo. 相似文献