This paper deals with two main problems in forest harvesting. The first is that of selecting the locations for the machinery to haul logs from the points where they are felled to the roadside. The second consists in designing the access road network connecting the existing road network with the points where machinery is installed. Their combination induces a very important and difficult problem...

2188 www.thelancet.com Vol 373 June 27, 2009 Aboard a Kenyan long-haul minibus (matatus), some hold their breath, others try to sleep, and many pray for the merciful intercession of the Almighty but, like characters resigned to a tragic script, they rarely speak up. In this universe of steel and glass, 15 feet by fi ve, the driver is king. “He tore his way down the road, hooting at those unluck...

The nearby goaf road in the extra-thick coal seam of Datong mining area exhibits intense strata pressure behavior, which affects working face mining. Herein, we study laws behavior this detail using various methods, including laboratory tests, theoretical analyses, numerical simulation, and field monitoring. Considering mine characteristics road, namely, roof cracking, two-side deformation, flo...

This work investigates the dynamics of heavy articulated vehicles and the problem of yawinstability caused by loss of traction. A mathematical model of the system is derived and applied to a typical vehicle used in mine haulage applications. Automatic control, based on differential wheel braking, is explored by simulation and shown to be potentially valuable in improving the safety of such vehi...

The harbour seal population in Svalbard occurs at the northernmost limit of the species' range. It experiences environmental extremes far beyond the norm for this species, including an extended period of polar night and extensive sea ice cover. In 2009 and 2010, 60 harbour seals (30 pups + 30 immature/mature seals) from this population were equipped with Satellite-Relay Data Loggers (SRDLs) to ...

The goal of this study was to model haul-out behavior of harbor seals (Phoca vitulina) in the Hood Canal region of Washington State with respect to changes in physiological, environmental, and temporal covariates. Previous research has provided a solid understanding of seal haul-out behavior. Here, we expand on that work using a generalized linear mixed model (GLMM) with temporal autocorrelatio...

Large numbers of harbor seals (Phoca vitulina) use habitat in tidewater glaciers in Alaska for pupping, breeding, and molting. Glacial fjords are also popular tourist destinations; however, visitation by numerous vessels can result in disturbance of seals during critical life-history phases. We explored factors affecting haul-out behavior of harbor seals at a glacial site frequented by tourism ...