An acoustically resonating medium has one or more nodes and anti-nodes. Insulating a first side of a resonating medium at a node from ambient air and exposing the opposite second side of the resonating medium at the node to ambient air results in thrust in the direction of the first side. Insulating the second side of a resonating medium at an anti-node from ambient air and exposing the first side of the medium at the anti-node to ambient air also results in thrust in the direction of the first side.

An acoustically resonating medium has one or more nodes and anti-nodes. Insulating a first side of a resonating medium at a node from ambient air and exposing the opposite second side of the resonating medium at the node to ambient air results in thrust in the direction of the first side. Insulating the second side of a resonating medium at an anti-node from ambient air and exposing the first side of the medium at the anti-node to ambient air also results in thrust in the direction of the first side.

Example methods, apparatuses, and/or articles of manufacture related to wild game calling are disclosed that may be implemented, in whole or in part, using a game calling device. In a particular implementation, a game calling device may closely imitate the call of an elk while air is passed over a reed to make a game call sound.

Example methods, apparatuses, and/or articles of manufacture related to wild game calling are disclosed that may be implemented, in whole or in part, using a game calling device. In a particular implementation, a game calling device may closely imitate the call of an elk while air is passed over a reed to make a game call sound.

An acoustic device includes an opening; a flange forming the opening; a first member including the opening and the flange; and a second member joined to the first member, thereby forming a cavity. The second member is formed of a material with a density lower than a material of the first member.

An acoustic device includes an opening; a flange forming the opening; a first member including the opening and the flange; and a second member joined to the first member, thereby forming a cavity. The second member is formed of a material with a density lower than a material of the first member.

An acoustic device includes an opening; a flange forming the opening; a first member including the opening and the flange; and a second member joined to the first member, thereby forming a cavity. The second member is formed of a material with a density lower than a material of the first member.

An acoustic device includes an opening; a flange forming the opening; a first member including the opening and the flange; and a second member joined to the first member, thereby forming a cavity. The second member is formed of a material with a density lower than a material of the first member.

Apparatus (1) for cooling an automobile component (20) by means of a gas, the apparatus comprising a cooling box (11) with a re-closeable opening (12) for receiving an automobile component (20) to be cooled, wherein at least one heat sink (13) is provided inside the cooling box (11) for cooling of the gas, and wherein the apparatus (10) includes at least one infra sound pulsator (2,3) arranged to provide an infra sound into said cooling box (11) to improve heat exchange of the gas both with a cooling surface of the at least one heat sink (13), and with the automobile component (20).

Apparatus (1) for cooling an automobile component (20) by means of a gas, the apparatus comprising a cooling box (11) with a re-closeable opening (12) for receiving an automobile component (20) to be cooled, wherein at least one heat sink (13) is provided inside the cooling box (11) for cooling of the gas, and wherein the apparatus (10) includes at least one infra sound pulsator (2,3) arranged to provide an infra sound into said cooling box (11) to improve heat exchange of the gas both with a cooling surface of the at least one heat sink (13), and with the automobile component (20).