摘要:
A beam forming system includes one or more beam forming elements that are arranged to provide a non-planar doubly ruled radiation surface. The surface is defined by two families of rulings such that the length of the rulings within each family are configured to provide a radiation surface with substantially straight boundary edges, and the beam forming system is arranged to form acoustic beams.
摘要:
A method and apparatus for determining a characteristic, such as the stiffness, of a portion of a wood specimen characterised by the steps of a) producing an acoustic signal in the wood specimen part way along the length of the wood specimen, and b) sensing a response in the wood specimen part way along the length of the wood specimen including a reverberation from a first end of the wood specimen, and c) calculating a characteristic of a portion of the wood specimen from analysis of the sensed response. A related method and apparatus may be used to determine a characteristic of a portion of a tree stem during harvesting of a tree and the characteristic used to optimise the value of a log cut from the stem.
摘要:
A swath beam acoustic transducer (100) for projecting and/or receiving acoustic swath beams (108). The transducer comprises an array of active acoustic elements (104) that are arranged to collectively provide an elongate concave radiation surface (106) with an associated acoustic aperture (110). The array of active acoustic elements (104) is operable to project and/or receive acoustic swath beams (108) via the radiation surface (106).
摘要:
A swath beam acoustic transducer (100) for projecting and/or receiving acoustic swath beams (108). The transducer comprises an array of active acoustic elements (104) that are arranged to collectively provide an elongate concave radiation surface (106) with an associated acoustic aperture (110). The array of active acoustic elements (104) is operable to project and/or receive acoustic swath beams (108) via the radiation surface (106).
摘要:
A method and apparatus for determining a characteristic, such as the stiffness, of a portion of a wood specimen characterised by the steps of a) producing an acoustic signal in the wood specimen part way along the length of the wood specimen, and b) sensing a response in the wood specimen part way along the length of the wood specimen including a reverberation from a first end of the wood specimen, and c) calculating a characteristic of a portion of the wood specimen from analysis of the sensed response. A related method and apparatus may be used to determine a characteristic of a portion of a tree stem during harvesting of a tree and the characteristic used to optimise the value of a log cut from the stem.
摘要:
A beam forming system (10) for acoustic or electromagnetic beams comprising one or more beam forming elements (2) that are arranged to provide a doubly ruled radiation surface.