A Video Survey on Minimal Risk Maneuvers and Conditions

Known issues at higher automation levels are hoped to be solved by the systems capability to automatically perform maneuvers in order to achieve a so-called minimal risk condition. In this paper, we contribute to this developing research field and emphasize the driver’s perspective. We have conducted a video survey with 49 participants showing different forms of maneuvers. The results show that drivers favor evasive maneuvers over coming to standstills and maneuvers to the left over right. However, the desired condition to be achieved is mainly the standstill on a shoulder lane. These conflicts should be considered for designing such systems and further investigated with different methodologies, such as driving simulators.

Countering low visibility in video survey of an estuarine fish assemblage

Sampling fish communities in tropical estuaries is inherently challenging due to poor visibility and the potential presence of dangerous fauna. We present two strategies for improving the identification of fishes in a turbid tropical estuary using video. The first was to attract species close to the camera by using two different bait types compared with no bait, and the second involved manipulating footage in the postfilming phase. No significant difference was found in the species richness recorded among camera bait treatments (thawed Australian sardines, canned sardines and unbaited), although baited cameras did detect 13 taxa not observed on the unbaited cameras. Three different image restoration algorithms (histogram equalisation, white balance and contrast-limited adaptive histogram equalisation) were compared in processing 22 instances where fish could not be confidently identified to species or genus level. Of these processed clips, five were able to be identified to species level by a panel of four coauthors. Further, two of the three algorithms yielded higher average confidence values for identification at the order, family, genus and species level than when the unprocessed footage was viewed. Image restoration algorithms can partly compensate for a reduction in image quality resulting from turbidity, addressing a key challenge for video-based sampling in estuaries.

Assessing pre-service history teachers' pedagogical content knowledge with a video survey using open-ended writing assignments and standardized rating items

This paper explores pre-service history teachers' ability to recognize and reflect on typical situations occurring in the history classroom and to link these to students' historical learning. Therefore, we draw on the concept of professional vision (Goodwin, 1994), which assumes that teachers need a professional knowledge base to monitor and to reason about teaching and student learning. Based on theoretical notions of teachers' pedagogical content knowledge (PCK), we investigated history teachers' professional vision by means of a video survey with integrated video clips, open-ended writing assignments and standardized item ratings. We collected data from 303 and 220 pre-service teachers at the beginning and at the end, respectively, of their subject-specific teacher training. The collected data open up the possibility of 'simultaneous triangulation' (Morse, 1991), which was used for test validation. First, we tested the reliability of the closed-ended test instrument using item response theory, in order to develop a feasible test model. Second, we investigated the validity of the test instrument by comparing test results with the findings of the open-ended writing task. In general, student teachers reached rather low test scores. They experienced difficulties in assessing classroom events in terms of their potential to support historical competencies and to evaluate the consequences for students' learning. Findings from the open writing assignment show that student teachers commented largely on generic teaching strategies while hardly noticing student learning. In sum, the chosen methodological approaches seem to contribute to a more distinct picture of preservice teachers' abilities to reason about history teaching and learning.