An extension of labeling techniques for finding shortest path trees

Label setting techniques are all based on Dijkstra's condition of always scanning the node with the minimum label, which guarantees that each node will be scanned exactly once; while this condition is sufficient it is not necessary. In this paper, we discuss less restrictive conditions that allow the scanning of a node that does not have the minimum label, yet still maintaining sufficiency in scanning each node exactly once; various potential shortest path schemes are discussed, based on these conditions. Two approaches, a label setting and a flexible hybrid one are designed and implemented. The performance of the algorithms is assessed both theoretically and computationally. For comparative analysis purposes, three additional shortest path algorithms - the commonly cited in the literature - are coded and tested. The results indicate that the approaches that rely on the less restrictive optimality conditions perform substantially better for a wide range of network topologies. (C) 2008 Elsevier B.V. All rights reserved

Brain response to affective pictures in the chimpanzee.

チンパンジーも他者の表情を素早く察知 -脳波測定による解明-.京都大学プレスリリース. 2013-02-26.Advancement of non-invasive brain imaging techniques has allowed us to examine details of neural activities involved in affective processing in humans; however, no comparative data are available for chimpanzees, the closest living relatives of humans. In the present study, we measured event-related brain potentials in a fully awake adult chimpanzee as she looked at affective and neutral pictures. The results revealed a differential brain potential appearing 210 ms after presentation of an affective picture, a pattern similar to that in humans. This suggests that at least a part of the affective process is similar between humans and chimpanzees. The results have implications for the evolutionary foundations of emotional phenomena, such as emotional contagion and empathy

Number of total switches observed as a function of hammer weight (L = 300 g, M = 600 g, H = 1200 g) and the direction of switches (L->H = from lighter to a heavier; H->L = from heavier to lighter) in Experiment 2.

<p>Number of total switches observed as a function of hammer weight (L = 300 g, M = 600 g, H = 1200 g) and the direction of switches (L->H = from lighter to a heavier; H->L = from heavier to lighter) in Experiment 2.</p

Median number of strikes needed to crack open a nut in Experiment 1.

<p>Also shown are the IQR and significance tests.</p

Number of total switches observed as a function of hammer weight (L = 300 g, M = 600 g, H = 1200 g) and the direction of switches (L->H = from lighter to a heavier; H->L = from heavier to lighter) in Experiment 1.

<p>Number of total switches observed as a function of hammer weight (L = 300 g, M = 600 g, H = 1200 g) and the direction of switches (L->H = from lighter to a heavier; H->L = from heavier to lighter) in Experiment 1.</p

Median number of strikes needed to crack a nut in Experiment 2.

<p>Also shown are the IQR and significance tests.</p

Average time (±SE) to solution for all subjects as a function of hammer weight.

<p>Also shown are the results for the overall significance test and the corresponding pair-wise comparisons (“<” denotes a significant difference between hammers).</p

Average time (±SE) to solution for all subjects as a function of hammer weight.

<p>Also shown are the results for the overall significance test and the corresponding pair-wise comparisons (“<” denotes a significant difference between hammers).</p

Median time needed to crack open a nut as a function of hammer weight in Experiment 1.

<p>Median time needed to crack open a nut as a function of hammer weight in Experiment 1.</p