Imagine that you are the owner of several art galleries and that you are in the process of hiring people to guard one of them. Unfortunately, with so many in your possession, you seem to have forgotten the exact shape of this particular one. In fact, all you can remember is that the art gallery is a polygon with n sides. Of course, guards have the capacity to turn around a full 360◦ and can see...

We introduce the notion of a normal gallery, a gallery in which any configuration of guards that visually covers the walls necessarily covers the entire gallery. We show that any star gallery is normal and any gallery with at most two reflex corners is normal. A polynomial time algorithm is provided deciding if, for a given gallery and a finite set of positions within the gallery, there exists ...

PURPOSE We aimed to determine the correlations between the elasticity values of solid breast masses and histopathological findings to define cutoff elasticity values differentiating malignant from benign lesions. MATERIALS AND METHODS A total of 115 solid breast lesions of 109 consecutive patients were evaluated prospectively using shear wave elastography (SWE). Two orthogonal elastographic i...

The conventional Cobb-Douglas production function model require strong assumptions such as the constant elasticity and the entire frontier efficiency. The varying elasticity production function is an useful extension but it does not take frontier efficiency into account, and the data envelope analysis model involves the use of linear programming methods to estimate the frontier efficiency where...

Elasticity is the ability of a software system to dynamically scale the amount of the resources it provides to clients as their workloads increase or decrease. Elasticity is praised as a key advantage of cloud computing, where computing resources are dynamically added and released. However, there exists no concise or formal definition of elasticity, and thus no approaches to quantify it have be...

Elasticity is a key property of cloud computing environments and one of the features which distinguishes this paradigm from other ones. An elasticity metric could be used to define and to monitor Service Level Agreements (SLAs), to compare and to benchmark different cloud providers or to improve provisioning and management decisions in real time if it could be measured with some simple procedur...

This paper presents u-Photo which is an interactive digital still image including information of pervasive services associated with networked appliances and sensors in pervasive computing environment. U-Photo Tools can generate a u-Photo and provide methods for discovering contextual information about these pervasive services. Users can easily find out this information through the metaphor of ‘...

Modulus of elasticity of flapper valve material is an important parameter for compressor design since it can affect efficiency and life time of the compressor. Modulus of elasticity is usually considered as a material constant. Actually, it can vary with material orientations and conditions and even environments such as temperature will also affect this value. Therefore, the parameters that can...