Metal oxides with a tunnelled structure are attractive as charge storage materials for rechargeable batteries and supercapacitors, since the tunnels enable fast reversible insertion/extraction of charge carriers (for example, lithium ions). Common synthesis methods can introduce large cations such as potassium, barium and ammonium ions into the tunnels, but how these cations affect charge stora...

In this paper, we define a variant of billiards in which the ball bounces around a square grid erasing walls as it goes. We prove that there exist periodic tunnels with arbitrarily large period from any possible starting point, that there exist non-periodic tunnels from any possible starting point, and that there are versions of the problem for which the same starting point and initial directio...

High speed wind tunnels are widely used in the study of fluid flow behavior around various objects. The air flow in the starting step of supersonic wind tunnels is transient including strong shock waves caused by the interaction of the tunnel main stream and the boundary layer at walls. To arrive in running step, the tunnel must be designed so as these waves leave immediately the test section. ...

This paper discuss two structures of WLAN system fit to Passenger Information Display System which is partly of subway.

Every few weeks, I take the subway to China. More accurately, I board a metro train in downtown Washington and travel 40 minutes to a Virginia suburb that’s mostly populated by people of Chinese heritage. The area is as much a center for Chinese visitors as it is a home to immigrants. The local restaurant serves Hong Shao Rou, a dish rarely served in more Americanized Chinese restaurants. A loc...

Graphical features on map, charts, diagrams and graph drawings usually must be annotated with text labels in order to convey their meaning. In this paper we focus on a problem that arises when labeling schematized maps, e.g. for subway networks. We present algorithms for labeling points on a line with axis-parallel rectangular labels of equal height. Our aim is to maximize label size under the ...

In various industrial fields, the operators use predesigned procedures either to solve problems or for troubleshooting. In the Parisian subway, such procedures exist since 1900. However, these procedures are not always exactly suited to the case at hand, and the operators generally prefer to customize a solution than to rely on fixed procedures. For the design of an “intelligent” assistant syst...

Nowadays IPv6 over IPv4 tunnels are widely used to form the global IPv6 Internet. This paper analyzes a packet fragmentation problem in IPv6 over IPv4 tunnels due to the MTU difference between IPv6 and IPv4 layers, which would greatly degrade the performance of the tunnels if ever happened. It also demonstrates an ICMP based attack that could induce the problem and gives some advice on how to d...

In [6], Goda, Scharlemann, and Thompson described a general construction of all tunnels of tunnel number 1 knots using “tunnel moves”. The theory of tunnels introduced in [3] provides a combinatorial approach to understanding tunnel moves. We use it to calculate the number of distinct minimal sequences of such moves that can produce a given tunnel. As a consequence, we see that for a sparse inf...

In this paper we propose an approach to recognize behaviors of groups of people in the subway. Violent behavior or vandalism performed by a group can be detected in order to alert subway security. The proposed system is composed of 3 main layers: the detection of people in the video, the detection and tracking of groups among the detected individuals and the detection of events and scenarios of...