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1.
Fatigue is a major cause of road traffic accidents. However, due to the blurred concept of fatigue and the lack of reliable testing devices (cf. the breath analyzer for alcohol levels), it is extremely difficult to incorporate fatigue in operationalized terms into either traffic or criminal law. Even though the Finnish Road Traffic Act explicitly forbids driving while tired, it is done only on a general level among other factors (sickness, etc.) that impair a driver's fitness to drive (Article 63). The present study was done to investigate the circumstances of fatigue driving offenses. From the Finnish Vehicle Administration driver record database we extracted all drivers (N = 768) punished under Article 63 from 2004-2005. Of these drivers, 90.4% committed a fatigue-related traffic offense. Accidents, predominantly single vehicle, were the most common (92.5%) consequence of fatigued driving. Although fatigue-related accidents are thought to be serious, our data shows that most of the accidents (81.6%) did not involve personal injuries. Almost every twentieth driver was punished because his vehicle was drifting on the road. The presence of alcohol or drugs was noted in 13% of the cases. Only 3.1% of the punished drivers officially denied being tired or falling asleep. Young men (≤35 yrs) represented 50% of all punished drivers. Time of day and seasonal effects were clear in this data. This study shows that even without a reliable fatigue detector and unambiguous criteria for recognizing the contribution of fatigue to accident causation, Finnish police and the courts punish a significant number of drivers every year on the basis of fatigue.  相似文献   

2.

ResearchGate has emerged as a popular professional network for scientists and researchers in a very short span. Similar to Google Scholar, the ResearchGate indexing uses an automatic crawling algorithm that extracts bibliographic data, citations, and other information about scholarly articles from various sources. However, it has been observed that the two platforms often show different publication and citation data for the same institutions, journals, and authors. While several previous studies analysed different aspects of ResearchGate and Google Scholar, the quantum of differences in publications, citations, and metrics between the two and the probable reasons for the same are not explored much. This article, therefore, attempts to bridge this research gap by analysing and measuring the differences in publications, citations, and different metrics of the two platforms for a large data set of highly cited authors. The results indicate that there are significantly high differences in publications and citations for the same authors captured by the two platforms, with Google Scholar having higher counts for a vast majority of the cases. The different metrics computed by the two platforms also differ in their values, showing different degrees of correlation. The coverage policy, indexing errors, author attribution mechanism, and strategy to deal with predatory publishing are found to be the main probable reasons for the differences in the two platforms.

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3.
Wang D  Zhao J  Hu S  Yin X  Liang S  Liu Y  Deng S 《Nano letters》2007,7(5):1208-1212
Using molecular dynamics (MD) simulation, we studied the structural transformation and breaking mechanism of a single crystalline copper nanowire under continuous strain. At a certain strain rate, an ensemble of relaxed initial states of the nanowire can preferentially go through one or more paths of deformation. In each deformation path, disordered atoms can be generated at the specific positions of the nanowire, where necking and breaking take place afterward. Such a breaking position is not predetermined; multiple initial states lead to a strain-rate-dependent, statistical distribution of breaking positions.  相似文献   

4.
5.
Here, we present a detailed analysis of the wing kinematics and wing deformations of desert locusts (Schistocerca gregaria, Forskål) flying tethered in a wind tunnel. We filmed them using four high-speed digital video cameras, and used photogrammetry to reconstruct the motion of more than 100 identified points. Whereas the hindwing motions were highly stereotyped, the forewing motions showed considerable variation, consistent with a role in flight control. Both wings were positively cambered on the downstroke. The hindwing was cambered through an ‘umbrella effect’ whereby the trailing edge tension compressed the radial veins during the downstroke. Hindwing camber was reversed on the upstroke as the wing fan corrugated, reducing the projected area by 30 per cent, and releasing the tension in the trailing edge. Both the wings were strongly twisted from the root to the tip. The linear decrease in incidence along the hindwing on the downstroke precisely counteracts the linear increase in the angle of attack that would otherwise occur in root flapping for an untwisted wing. The consequent near-constant angle of attack is reminiscent of the optimum for a propeller of constant aerofoil section, wherein a linear twist distribution allows each section to operate at the unique angle of attack maximizing the lift to drag ratio. This implies tuning of the structural, morphological and kinematic parameters of the hindwing for efficient aerodynamic force production.  相似文献   

6.
Leydesdorff  Loet 《Scientometrics》2018,116(3):2113-2121
Scientometrics - The dilemma which remained unsolved using Rao-Stirling diversity, namely of how variety and balance can be combined into “dual concept diversity” (Stirling in SPRU...  相似文献   

7.
Although research collaboration has been studied extensively, we still lack understanding regarding the factors stimulating researchers to collaborate with different kinds of research partners including members of the same research center or group, researchers from the same organization, researchers from other academic and non-academic organizations as well as international partners. Here, we provide an explanation of the emergence of diverse collaborative ties. The theoretical framework used for understanding research collaboration couples scientific and technical human capital embodied in the individual with the social organization and cognitive characteristics of the research field. We analyze survey data collected from Slovenian scientists in four scientific disciplines: mathematics; physics; biotechnology; and sociology. The results show that while individual characteristics and resources are among the strongest predictors of collaboration, very different mechanisms underlie collaboration with different kinds of partners. International collaboration is particularly important for the researchers in small national science systems. Collaboration with colleagues from various domestic organizations presents a vehicle for resource mobilization. Within organizations collaboration reflects the elaborated division of labor in the laboratories and high level of competition between different research groups. These results hold practical implications for policymakers interested in promoting quality research.  相似文献   

8.
A number of guidelines and directives have reinforced the need for a more formalised approach to Independent Ethic Committees (IECs) and support the need to audit IECs. The key elements of an audit of an IEC are reviewed within the context of the European Guidelines for Auditing Independent Ethics Committees published by the European Forum for Good Clinical Practice (EFGCP). Auditing requirements in these recent guidelines and the EU Clinical Trial Directive are discussed as well as the methodology and type of documentation and SOPs that should be present at an audit. It is argued that both inspectorates and independent auditors need to conduct such audits to improve the overall global standard.  相似文献   

9.
The context for modelling transport systems and their use is set out. Such modelling is based on representing the transport system by a network of nodes and links, and the characteristics of this representation needed to reflect the principal realities of the system are outlined. The characteristics of use of the system that need to be reflected are described. Purposes of the modelling are set out and its evolution is described, starting from the basic traffic assignment model and discussing its generalizations and extensions in the search for greater realism-first in steady-state modelling for fixed demand, and then considering variable demand and time dependence. Further progress towards appropriate realism is seen as requiring communication and cooperation between the modellers and the users of models, helped perhaps by combining the advantages of analytical modelling and microsimulation.  相似文献   

10.
This paper investigates how and why scientific video articles are communicated on Twitter. We use video articles published in the Journal of Visualized Experiments (JoVE) as our objects of study. We harvested tweets from October 2011 to November 2015 that contained one or more JoVE links. These tweets “citing” JoVE articles were analyzed both statistically and qualitatively. In this paper, we present the distribution of these tweets, with a closer look at the affordance use of Twitter including hashtags and mentions. In addition, we conducted a content analysis of the sampled Twitter accounts and tweets. We present the coding schemes and results of both Twitter user accounts and tweets text. In addition to the analysis of the coding results, we discuss the content of the tweets with particular attention to issues including the video/visual feature mentioned, the role of Twitter bots, and self-promotion of different stakeholders in the Twitter communication of JoVE video publications.  相似文献   

11.
12.
Sadly, in 2020, sexual harassment and harassment on the grounds of sex are still a major social problem. In the digital era, these have acquired new aspects, but there are also new technological tools to fight against them. Usually public organizations have instruments to deal with these issues, but the presence of Information and Communication Technologies (ICT) is minimal if at all. In this paper, we will show the scarce presence of these new technological measures in universities, and with a review of the literature, offer a set of measures to improve the management of sexual harassment and harassment on the grounds of sex. As a case study, we will present the situation of ICT in sexual harassment management in Spanish public universities.  相似文献   

13.
It is widely accepted that concrete-embedded steel is in a passive state. However, there are some exceptional circumstances that induce corosion in an active state within concrete structures, thereby severely reducing their durability. This two-part paper analyses some major questions which, however elementary they may be, are still controversial in scientific, technical and economic terms. The first part provides answers to the following questions on the steel/concrete/environment system:
  1. How does steel in concrete normally behave?
  2. What are the initiating factors for depassivation?
  3. What are the effects of corrosion?
  4. What is the morphology of corrosion in the active state? and
  5. What is the corrosion rate threshold above which the durability of reinforced concrete structures is impaired? The answers to these questions are provided in light of experimental results, most of which were obtained by the authors themselves.
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14.
Since the ferromagnetic -(Fe3O4) nanoparticles were firstly reported to exert enzyme-like activity in 2007, extensive research progress in nanozymes has been ma...  相似文献   

15.
We had shown earlier that viewers prefer to look at artworks under illuminants of approximately 3600 K. In the latest paper we tested the hypothesis that the preferred illuminant is one that appears neither warm nor cool and repeated the settings at each of four illuminances to test the stability of the findings. Observers looked at a neutral white reflectance standard hung on a matte-gray wall lit by overhead banks of lamps whose combined value could be adjusted continuously between 3000 and 4400 K while illuminance was kept constant. Illuminance ranged from 50 to 2000 lux. Observers adjusted color temperature until they were satisfied that the standard looked neither warm nor cool. The mean for a group of eight observers was approximately 3700, independent of intensity; this corresponds to a dominant wavelength of approximately 580 nm. In a separate study four observers scaled the apparent warmth or coolness of flashes of equiluminant monochromatic lights; the warm-cool transition was between 560 and 580 nm; warmness was completely predicted by the perceived redness of each light as derived from hue and saturation scaling functions from the same group.  相似文献   

16.
Kuld  Lukas  O’Hagan  John 《Scientometrics》2018,114(3):1207-1225
Scientometrics - This paper builds on previous work by reviewing the key literature relating to the rise in co-authorship in economics and by presenting further new evidence on several features of...  相似文献   

17.
This article highlights recent successes in the field of chemical genetics. It discusses the challenges inherent in this interdisciplinary research field and focuses on the essential role that the biologically aware synthetic chemist can play.  相似文献   

18.
Graphene annealing: how clean can it be?   总被引:2,自引:0,他引:2  
Lin YC  Lu CC  Yeh CH  Jin C  Suenaga K  Chiu PW 《Nano letters》2012,12(1):414-419
Surface contamination by polymer residues has long been a critical problem in probing graphene's intrinsic properties and in using graphene for unique applications in surface chemistry, biotechnology, and ultrahigh speed electronics. Poly(methyl methacrylate) (PMMA) is a macromolecule commonly used for graphene transfer and device processing, leaving a thin layer of residue to be empirically cleaned by annealing. Here we report on a systematic study of PMMA decomposition on graphene and of its impact on graphene's intrinsic properties using transmission electron microscopy (TEM) in combination with Raman spectroscopy. TEM images revealed that the physisorbed PMMA proceeds in two steps of weight loss in annealing and cannot be removed entirely at a graphene susceptible temperature before breaking. Raman analysis shows a remarkable blue-shift of the 2D mode after annealing, implying an anneal-induced band structure modulation in graphene with defects. Calculations using density functional theory show that local rehybridization of carbons from sp(2) to sp(3) on graphene defects may occur in the random scission of polymer chains and account for the blue-shift of the Raman 2D mode.  相似文献   

19.
This is a community-based sequential case series of 50 individuals who committed suicide by jumping from bridges in two regions of Sweden. Of the 50 subjects, 32 were men and 18 women, with a median age of 35 years. At least 40 had psychiatric problems. The frequency of suicide was highest during the summer months and during the weekends. A total of 27 bridges were used, with a total length of just under 9 km. Three bridges accounted for almost half of all suicides. Limiting the availability of one method of committing suicide is reported to reduce the overall suicide rate; why suicide and injury suicide preventive measures might be considered. Since this study demonstrates that few bridges attract suicide candidates, this injury mechanism needs to be acknowledged by the road system owners and included in the safety work.  相似文献   

20.
The safe community concept was put into practice in order to reduce the number of unintentional injuries occurring in the Falun municipality. A community-based injury prevention programme was initiated in 1989 and has been gradually built up since that time. The prevention endeavours were based primarily on active intervention strategies through the provision of information, supervision, education and training. After 5 years of an active intervention programme, a significant effect was found as regards the injury rates for both outpatients as well as patients discharged from hospitals. The objectives of this study were: to examine whether the character of the prevention endeavours was a determining factor on the outcome (recorded as in-patient injury cases); to evaluate the effects of this programme, which is still in practice, compared to long-term historical trends; and to draw comparisons with other community-based programmes. A category of 'most targeted risks' was identified as being different with respect to how the injury mechanisms involved were targeted through the programme activities. The development within the injury rates for this group, comprised predominantly of injuries caused by falls at the same level, was significantly different than those for the groups categorized as 'less targeted' and 'non-targeted'. The general effect of the programme appeared to be a neutralization of an otherwise upward trend in the injury rates. A particular effect was demonstrated in the number of fall injuries, including femoral fractures. It was also noted that there was still a reduction in injuries after 7 years. However, it was possible to surmise a waning effect during the last 2 years of the programme while still in progress. This observation suggests that a community-based injury prevention programme must be continuously renewed and reinforced.  相似文献   

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