Piecewise-linear terrains (“roofs”) over simple polygons were studied by Aichholzer et al. (1995) in their work on straight skeletons of polygons. We show how to construct a roof over a simple polygon that has minimum (or maximum) volume among all roofs that drain water. Such a maximum-volume (minimumvolume) roof can have quadratic (maybe cubic, resp.) number of facets. Our algorithm for comput...

Accurate and realistic 3-dimensional models of urban environments are increasingly important for applications like virtual tourism, city planning, Internet search and many emerging opportunities in the context of “ambient intelligence”. Applications like Bing-Maps or Google Earth are offering virtual models of many major urban areas worldwide. While initially these data sets support visualizati...

Along with the strong movement towards sustainable urban environments, there is an increasing use of green roof systems, including the semi-extensive green roofs, which are composed of lightweight layers of freedraining material that support low-growing, tough, and drought-resistant vegetation. Various kinds of green roof systems are also used at street levels, on the top of underground car par...

Roof rats (Rattus rattus) and deer mice (Peromyscus maniculatus) are occasional pests of nut and tree fruit orchards throughout California and in many other parts of the USA and beyond. In general, the most practical and cost-effective control method for rodents in many agricultural environments is the use of rodenticides (toxic baits), but little or no information exists on the efficacy of cur...

From the 86 species allocated in the genus Rhinella, 25 have their tadpoles described and only R. arenarum, R. chrysophora, R. icterica, R. ornata, R. schneideri and R. spinulosa have aspects of the internal oral morphology evidenced. Herein, the internal oral morphology from 12 species of Rhinella distributed between the morphological groups of R. crucifer, R. granulosa, R. marina and R margar...

The fibronectin fibril matrix on the blastocoel roof of the Xenopus gastrula contains guidance cues that determine the direction of mesoderm cell migration. The underlying guidance-related polarity of the blastocoel roof is established in the late blastula under the influence of an instructive signal from the vegetal half of the embryo, in particular from the mesoderm. Formation of an oriented ...

Floating roofs are widely used to store petroleum products with high volatility. This is to prevent the product loss and to ensure safe environment around the storage tanks. However, small number of researches were accomplished. These researches aim at study the design of the floating roof and the associated risks that it faces during operation. In an effort to compensate the lack of knowledge ...

Monitoring of roof activity is a primary measure adopted in the prevention of roof collapse accidents and functions to optimize and support the design of roadways in underground coalmines. However, traditional monitoring measures, such as using mechanical extensometers or electronic gauges, either require arduous underground labor or cannot function properly in the harsh underground environment...

Orbital roof fractures are relatively uncommon in craniofacial surgery but present a management challenge due to their anatomy and potential associated injuries. Currently, neither a classification system nor treatment algorithm exists for orbital roof fractures, which this article aims to provide. This article provides a literature review and clinical experience of a tertiary trauma center in ...

We report a case of a 12-year-old male child who presented with a gradual onset exopthalmos involving the left eye. The plain radiographs of the skull showed hyperostosis of the left orbital roof. The computerized tomography (CT) scan revealed an intradiploic orbital roof tumor with expansion of both the tables of the orbital roof. The tumor was completely excised by an extradural route using a...