Abstract: A housing for an aero-acoustic processing machine having rotational drive apparatus coupled to rotate an air impeller to draw air and material to be processed through an axial inlet system and expel the air and processed material through a transverse outlet. The housing includes an enclosure incorporating at least one layer of noise attenuation materials surrounding the aero-acoustic processing machine, the enclosure having a material inlet port, an air inlet port and an exhaust port for outputting processed product with air. Airflow paths that are required for operation of the aero-acoustic processing machine are provided to enable airflow into the housing whilst significantly reducing noise emission.

Abstract: The disclosure relates to acoustic panels and methods for preparing them. The disclosure relates more particularly to panels having a porous facing and to methods for making such panels. One aspect of the disclosure is an acoustic panel comprising a base structure. The base structure has one or more edges, an outward major surface having a total area, and an inward major surface opposing the outward major surface. The base structure has a noise reduction coefficient (NRC) of at least about 0.3. The panel includes a coating layer directly disposed on the outward major surface of the base structure, the coating layer being formed of an open-cell foam. The coating layer has an exterior major surface opposing the outward major surface of the base structure. The coating layer is substantially scattering for light in the wavelength range of 380 nm to 780 nm, and has an absorption coefficient of less than 0.5 for acoustic frequencies in the range of 100 Hz to 10,000 Hz.

Abstract: This disclosure provides for an auditory modification apparatus to facilitate extraction of information from an auditory observation stream. The approach may be used to reveal features about the environment, or to simplify processing of the incoming audio stream. The apparatus acts on the incoming auditory stream by nature of its shape, and that shape either is passively static or actively manipulated. Preferably, the apparatus has given shape characteristics to reveal features of the environment, such as directionality of a noise, size of an enclosed space, or materials of its construction, that are not otherwise detectable or easy to process with conventional approaches. Further advantage exists in the notion of actively manipulating the shape of the apparatus in conjunction with its operation to facilitate information extraction in a dynamic manner.

Abstract: The invention concerns a sound insulation element (10), that utilizes a strong force-network as a principle energy dissipating mechanism, whereat the strong force-network is generated through complex interactions of solid particles (14) in a granular system, which leads to formation of maximal number of interconnecting pairs-of-forces according to 3rd Newton's Law, whereat said strong force-network is realized by using a granular material (12) made from at least one solid material with a specific skewed multimodal particles-size-distribution, comprising a granular material (12) consisting of particles (14), and a supporting structure (40) having at least one cavity (42), whereat the at least one cavity (42) is filled with particles (14) of the granular material (12).

Abstract: A sound-insulation material for a vehicle has high rigidity and is capable of exhibiting sufficient sound insulation performance against noise having a frequency of 500 Hz to 5000 Hz generated in a vehicle, while maintaining low weight. The sound-insulation material for a vehicle of the present invention has a multilayer structure, the material including: a hard layer having tubular cells, the tubular cells being arranged in a plurality of rows; and a soft layer provided on one surface of the hard layer, in which a ratio of a dynamic spring constant Kd to a static spring constant Ks, of a structure having the hard layer and the soft layer, is 0<Kd/Ks?1.5.

Abstract: A Helmholtz resonator having a plurality of resonator chamber modules formed into an array. The array is configured to dampen sound. A module of the plurality of resonator chamber modules includes a first chamber and a second chamber. The first and second chambers have different lengths and are tuned to dampen different frequencies of sound.

Abstract: There is provided a sound-absorbing material for a vehicle, capable of stably yielding desired sound absorption performance while reducing weight of the sound-absorbing material for a vehicle. The sound-absorbing material for a vehicle of the present invention has a multilayer structure, including: a core layer in which tubular cells are arranged in a plurality of rows; and an airflow-blocking resin film layer adhered to one surface of the core layer. The relationship between the Young's modulus E (MPa) of the airflow-blocking resin film layer 40 and the surface density M (g/m2) of the layer structure on the first airflow-blocking resin film layer 40 side with respect to the core layer 10 is 0.5<E/M<21.

Abstract: There is provided a sound-insulation material for a vehicle that can reduce the weight thereof and exhibit sufficient sound insulation performance against noise of 500 Hz to 6400 Hz generated in vehicles. The sound-insulation material for a vehicle, of the present invention, includes: a core layer having tubular cells, the tubular cells being arranged in a plurality of rows; an airflow-blocking resin film layer provided on one surface of the core layer; and a decoupling layer provided on the airflow-blocking resin film layer; and an average (P/v)/Za is 2.8 to 10 between 500 and 6400 Hz, where: P and v are respectively a sound pressure and a particle velocity on a surface of the airflow-blocking resin film layer provided on the core layer, the surface being opposite to the core layer; and Za is an acoustic impedance of the decoupling layer.

Abstract: The invention relates to a method for manufacturing a nonwoven fabric having an air permeability of 2000 l/m2/s or less when measured at a pressure difference of 200 Pa according to EN ISO 9237, the method comprising the steps of: providing at least two sets of fibers, wherein a first fiber set comprises a significant level of splittable fibers and a second fiber set comprises a low level of splittable fibers or no splittable fibers; using the first fiber set to form at least one first fibrous web in a first web formation process and using the second fiber set to form at least one second fibrous web in a second web formation process; stacking the first and second webs so obtained to provide a multilayer web including two distinct layers of fibrous webs; and bonding the multilayer web. The invention further relates to a nonwoven fabric obtainable by such process and the use of such nonwoven fabric in acoustic isolation applications.

Abstract: A tripod includes a main body having a center column with a first end, a second end opposite the first end, and a longitudinal axis extending through the first end and the second end, and a plurality of legs coupled to the center column. The tripod system also includes a battery receptacle supported at the first end of the center column. The battery receptacle has a first interface configured to mechanically and electrically couple to a battery pack. The tripod system further includes a head supported at the second end of the center column. The head has a second interface configured to mechanically and electrically couple to a luminaire. The second interface is complementary to the first interface.

Abstract: The invention relates to a stethoscope comprising a stethoscope chestpiece comprising a body member having a bottom surface and an ejector mark disposed on the bottom surface. The stethoscope chestpiece has a weight of at least 50 g, a surface roughness (Ra) no greater than 1.6 microns in an unpolished state, and reflectivity (% R) of at least 60% in an unpolished state. The stethoscope chestpiece can be produced by injection molding, extruding, or pressing a metallic thermoplastic composition into a mould forming a green molded body, debinding a portion of binder material from green molded body forming a brown molded body without reducing the temperature by more than 80° C., and sintering the brown molded body to form the stethoscope chestpiece.

Abstract: A hollow structure has a hollow body with an annular first space and at least one resonator. In the resonator there is formed an elongated second space with a pair of openings at two ends thereof. Each of the pair of openings opens inwardly toward the interior of the first space. The ratio of the length of a centerline of the second space to the length of a centerline of the first space is within a range of from 0.45 to 0.55. The second space is disposed in a curve along a circumferential surface of the first space and is shaped such that one of the two ends of the second space is folded back toward the other end.

Abstract: The cleaner according to the present disclosure includes a main body forming an airflow path through which air is sucked and exhausted; a dust separation unit disposed in the airflow path and configured to separate dust from the air; a fan module disposed in the airflow path and configured to move the air in the airflow path; and a noise control module including a speaker, and configured to control the output of the speaker to increase a level of the noise of at least one range of the frequency range of 2000 Hz or more and 8000 Hz or less.

Abstract: A suppressor having a body and a first connector half coupled to the body, wherein the first connector half includes a first component that includes at least one channel and a first surface; and wherein the body provides a second surface, wherein a gap between the first surface and the second surface defines at least one track; wherein the gun includes a second connector half comprising at least one protrusion, wherein the protrusion and channel have corresponding shapes that allow the protrusion to be inserted through the channel and into alignment with the track, wherein the first component may be rotated with respect to the protrusion and the body to bring the protrusion out of alignment with the channel so that the first and second surfaces clamp the protrusion to thereby secure the first connector half and second connector half with respect to each other.

Abstract: A sound absorber includes cavities mutually different in at least one of shape and size. A wall of a first cavity included in the cavities includes a first region and a second region. Through-holes connecting an interior to an exterior of the first cavity is formed in the first region. No through-holes connecting the interior and the exterior of the first cavity is formed in the second region adjacent to the first region. A wall of a second cavity included in the cavities includes a third region and a fourth region. Through-holes connecting an interior to an exterior of the second cavity is formed in the third region. No through-holes connecting the interior and the exterior of the second cavity is formed in the fourth region adjacent to the third region. Size of through-holes in the first region is different from size of through-holes in the third region.

Abstract: The present invention is directed to an improved gypsum board, such as an improved sound damping gypsum board. The gypsum board comprises a gypsum core including gypsum and a sound damping polymer. The gypsum core includes a first gypsum layer surface and a second gypsum layer surface opposing the first gypsum layer surface. In addition, a first encasing layer is disposed on the first gypsum layer surface and a second encasing layer is disposed on the second gypsum layer surface.

Abstract: An acoustic block manufacturing method includes: mixing zeolite powder with water to form a mixed liquid; making the mixed liquid into an ice cube; providing a vacuum environment to make the ice cube undergo gas phase sublimation; and feeding parylene into the vacuum environment in a manner of chemical vapor deposition to form an acoustic block having a porous structure. The acoustic block can effectively reduce resonance frequency. An acoustic device with acoustic blocks is also provided and has the same effect.

Abstract: An object is to provide a silencing system that can achieve both high ventilation performance and high soundproof performance, can silence a plurality of pieces of resonant sound, and has high general-purpose properties since the silencing system does not need to be designed according to a tubular member. The silencing system includes one or more silencers that are disposed in a tubular member provided to penetrate a wall separating two spaces, and satisfies “0<Re[Bn]<1” and “Im[Bn]>0” in a case where a standardized effective modulus of elasticity in an interior space of the tubular member in which the silencers are disposed is denoted by Bn.

Abstract: An object is to provide a silencing system that includes a silencer disposed in a ventilation sleeve, can suppress the generation of negative pressure in the interior, and can prevent a door or the like of an interior entrance from being difficult to open. The silencing system includes one or more silencers that are disposed in a ventilation sleeve provided to penetrate a wall separating two spaces, and “?A>10C?(0.1/P)×TL” is satisfied in a case where a gap equivalent area of the ventilation sleeve in which the silencer is installed is denoted by ?A and a normalized sound transmission loss in an octave band in which a first resonant frequency of the ventilation sleeve is present is denoted by TL. C denotes a constant determined by a measurement system in a case where there is no silencer and P denotes a transmission efficiency coefficient.

Abstract: A panel for attenuating noise is disclosed comprising a face skin having a first inner surface, a base skin having a second inner surface, a cellular core connected to and forming a plurality of cells between the face skin and the base skin, wherein the cellular core is defined by a cell structure having a plurality of cell walls extending between the face skin and the base skin defining each of the plurality of cells and a septum disposed within each of the plurality of cells, the septum defining an upper chamber proximate the face skin and a lower chamber proximate the base skin, wherein the face skin comprises a plurality of perforations fully through the face skin and in fluid communication with the upper chamber.