A reference microphone for detecting noise is located under a first duct. The noise is in the form of a first plane wave in the first duct. A speaker is located on a top of the first duct. Connected to an upper part of the first duct is a second duct including an error microphone. The first plane wave in the first duct passes through an acoustic path and reaches the second duct. The error microphone detects the sound, and the speaker outputs a second plane wave with an opposite phase for canceling the first plane wave.

A partial enclosure for inhibiting sound passing into and out of the partial enclosure includes an absorber-barrier or an absorber-barrier-absorber, each made from sound absorbing material and sound barrier material and arranged to form the partial enclosure. The enclosure also includes an adaptive frequency matched sound-masking system. The absorber-barrier or absorbed-barrier-absorber is positioned to block or inhibit unwanted sound from various positions of a source of the unwanted sound, or motion of the source of the unwanted sound. The adaptive frequency matched sound-masking system includes a sound generating device arranged on or in the partial enclosure to emit anti-noise signal to cancel or inhibit the unwanted sound.

Certain example embodiments relate to an acoustic wall assembly that uses active and/or passive sound reverberation to achieve noise-disruptive functionality, and/or a method of making and/or using the same. With the active approach, sound waves in a given frequency range are detected by a sound masking circuit. Responsive to detection of such sound waves, an air pump (e.g., speaker) is used to pump air in the wall assembly to actively mask the detected sound waves via reverberation and/or the like. The wall assembly may include one, two, or more walls, and the walls may be partial or full walls. With the passive approach, sound waves in a given frequency range are disrupted via features (e.g., holes, slits, etc.) formed in and/or on a wall itself. These techniques may be used together or separately, in different example embodiments.

Certain example embodiments relate to an acoustic wall assembly that uses active and/or passive sound reverberation to achieve noise-disruptive functionality, and/or a method of making and/or using the same. With the active approach, sound waves in a given frequency range are detected by a sound masking circuit. Responsive to detection of such sound waves, an air pump (e.g., speaker) is used to pump air in the wall assembly to actively mask the detected sound waves via reverberation and/or the like. The wall assembly may include one, two, or more walls, and the walls may be partial or full walls. With the passive approach, sound waves in a given frequency range are disrupted via features (e.g., holes, slits, etc.) formed in and/or on a wall itself. These techniques may be used together or separately, in different example embodiments.

A sound-absorbing material nonwoven fabric includes: 30 to 80 mass % of short fibers A having a fineness of 0.4 to 0.9 dtex; and 20 to 70 mass % of short fibers B having a fineness of 1.1 to 20.0 dtex. A carding passage coefficient of the short fibers A calculated from equation (1) is in a range of 15 to 260. The equation (1) is carding passage coefficient=(fineness×strength×√elongation percentage×√number of crimps×√crimping degree)/(fiber length).

A reference microphone for detecting noise is located under a first duct. The noise is in the form of a first plane wave in the first duct. A speaker is located on a top of the first duct. Connected to an upper part of the first duct is a second duct including an error microphone. The first plane wave in the first duct passes through an acoustic path and reaches the second duct. The error microphone detects the sound, and the speaker outputs a second plane wave with an opposite phase for canceling the first plane wave.

Systems and methods are provided for an infant incubator having features for active noise cancellation, including enclosure designs, positioning systems, and error sensor selection.

The present invention provides an elongated active thermo-regulated neonatal transportable incubator (ANTI), having a main longitudinal axis with a proximal end and an opposite distal end comprising adjacent to at least one of the ends a temperature regulating vent (TRV). The TRV is configured to stream air from one end towards the opposite end substantially along the axis, and the ANTI is configured, by means of size and shape, to accommodate the neonate in parallel to the axis. Further the ANTI can be configured by means of size shape and material to at least partially inserted into an MRD having an open bore in its longitudinal axis, further accommodating the neonate parallel to the MRD bore. An incubator with a temperature regulating vent located outside the incubator and its base.

A unit cell of an artificial phononic crystal for building of an artificial phononic metamaterial, showing reduced mechanical vibrations in a defined frequency range with at least one band gap in the band structure dispersion relation of the unit cell. The unit cell includes at least one building block and at least one mechanical connection connected to the building block, showing reduced mechanical vibrations in a defined frequency range with tailored dispersion properties with at least one band gap is sought. This is accomplished by forming the building block as a toroid, with a central opening and a front surface from which a first multiplicity of struts, which are tiltable relatively to the principal direction, is extending from the front surface. More than one strut is inclined with respect to the principal direction so that a rotation of the toroid around the principal direction is possible.

Disclosed is a waterproof sound-transmitting sheet, which includes a waterproof layer of a nonporous material and a support layer of a porous material, and maintains waterproof performance and sound transmission performance at a water pressure of about 10 atm. The disclosed waterproof sound-transmitting sheet includes a waterproof layer formed of a film shape of a nonporous material, a first adhesive layer having one surface adhered to one surface of the waterproof layer, and a support layer formed of a film shape of a porous material, and having one surface adhered to the other surface of the adhesive layer; and the support layer can be composed of metal mesh or nonwoven fabric.