No abstract

We propose a robust two-dimensional polynomial beamformer design method, formulated as a convex optimization problem, which allows for flexible steering of a previously proposed data-independent robust beamformer in both azimuth and elevation direction. As an exemplary application, the proposed twodimensional polynomial beamformer design is applied to a twelveelement microphone array, integrated into the head of a humanoid robot. To account for the effects of the robot's head on the sound field, measured head-related transfer functions are integrated into the optimization problem as steering vectors. The two-dimensional polynomial beamformer design is evaluated using signal-independent and signal-dependent measures. The results confirm that the proposed polynomial beamformer design approximates the original fixed beamformer design very accurately, which makes it an attractive approach for robust real-time dataindependent beamforming.Index Terms-Robust superdirective beamforming, polynomial beamforming, white noise gain, robot audition

The history of the water supply in Lisbon includes some great works of note such as the "Aqueduto das Águas Livres" (1748), the Aqueduct of the Free Waters, a remarkable work of hydraulic engineering, which was the first great achievement to solve the chronic lack of water in Lisbon. The "Reservatório da Mãe d'Água" (1834), the Reservoir Mother of Water was a huge water cistern built to receive and distribute the water directed through the Aqueduct of the Free Waters, which supplied water to Lisbon. Water is one of the most important natural resources; the sustainable management of water resources is a major global challenge. The United Nations Environment Programme is implementing or participating in several environmental assessments. Fresh water, in its consumable condition, represents less than 1% of the quantity of water on our planet. It is indispensable to study the superficial and subterranean water resources, taking into consideration the cycle of the water, its quality and use. Democratic societies and developed technologies have the added responsibilities of promoting sustainable development to provide rational and efficient management of the water resources. The Water Museum has become a unique place to stimulate art, encouraging the preservation of heritage and education for sustainable development. On the 3rd July, Manuel Carmo's installation "In Definition-The corridor of water in life" confirmed the strong relationship that exists between human beings and water. On 12th July, "Mother of Water" returned to its usual condition, filled again with water. Manuel Carmo, a remarkable artist, sculptor and painter, as well as a poet devoted to aesthetic projects, expressed the importance of water as an artistic and natural vital resource.