In ventilated tunnel fires, smoke and hot combustion products may form a layer near the ceiling and flow in the direction opposite to the ventilation stream. The existence of this reverse stratified flow has an important bearing on fire fighting and evacuation of underground mine roadways, tunnels and building corridors. In the present study, conducted by the National Institute for Occupational...

In this paper, an automatic robotic inspector for tunnel assessment is presented. The proposed platform is able to autonomously navigate within the civil infrastructures, grab stereo images and process/analyse them, in order to identify defect types. At first, there is the crack detection via deep learning approaches. Then, a detailed 3D model of the cracked area is created, utilizing photogram...

As a part of a study of pollution of the air by motor vehicles, measurements have been made in two London road tunnels during periods of high traffic density. The concentrations of smoke and polycyclic hydrocarbons found there are much higher than the average values in Central London, but they are of the same order of magnitude as those occurring during temperature inversions on winter evenings...

We consider the problem of tunneling MPLS label switched paths (LSPs) over an optical network in which λ-channels (lightpaths) of a fixed capacity are the main mechanism of transport. While any set of LSPs, each LSP having an arbitrary rate, can be tunneled over a given λ-channel as long as the aggregate rate does not exceed the channel’s capacity, intuition suggests that this flexibility has a...

Sodium hexa-titanate (Na(2)Ti(6)O(13)) nanofibers, which have microporous tunnels, were prepared by heating sodium tri-titanate nanofibers with a layered structure at 573 K. The void section of the tunnels consist of eight linked TiO(6) octahedra, having a quasi-rectangular shape and the sodium ions located in these tunnel micropores are exchangeable. The exchange of these sodium ions with diva...

PURPOSE The purpose of this study was to investigate and report on a new intraoperative measuring technique to place the anterior cruciate ligament (ACL) femoral tunnel in the center of the native ACL femoral insertion site. METHODS We investigated a novel measuring technique based on identifying the proximal border of the articular cartilage and using a specific ruler parallel to the femoral...

Identifying encrypted application traffic represents an important issue for many network tasks including quality of service, firewall enforcement and security. Solutions should ideally be both simple – therefore efficient to deploy – and accurate. This paper presents a machine learning based approach employing simple Packet Header feature sets and statistical flow feature sets without using the...

The project named “the rescue system and key technology of high-speed railway in perilous mountains” primarily focuses on current railway constructions and operations in China. To state the relationship between risk events and risk factors, we classified the risk sources of operating tunnels of high-speed railway in perilous and mountainous area and established a hierarchical assessment system ...

Night illumination of expressway long tunnels in China was far from drivers’ demand and caused lots of traffic accidents and electricity wasting. In order to solve this problem, reasonable night luminosity in expressway long tunnels in China was studied. Based on a visual disturbance generation mechanism, the mistakes in night illumination of Chinese expressway long tunnels were analyzed. Real ...