Disclosed is an ultrasonic transducer and a manufacturing method thereof. The transducer comprises a piezoelectric composite array having an array of rigid posts made of a piezoelectric material, with kerf spaces between the posts filled with a low density aerogel material.

An actuator providing a large shear movement in a chosen direction. The angle of inclination of the fibers relative to the chosen direction is larger than 2? and smaller than 40?; the spaces between the piezoelectric fibers of the active layer are filled with an incompressible elastic material; the active layer comprises at least two dimensionally stable elongate elements parallel to the chosen direction; the ends of each fiber are adhesively bonded to said dimensionally stable elements using a rigid adhesive; and said dimensionally stable elements are adhesively bonded, by a rigid adhesive, to said electrode-bearing layers.

A charge-generating thread for bacterium-countermeasure that includes a charge-generating fiber. The charge-generating fiber generates a charge by energy imparted from the outside of the fiber so as to restrain the proliferation of bacteria by the generated charge.

The present invention relates to nanofibers. In particular, the present invention relates to potassium niobate nanofibers. In an aspect of the present invention, there is provided a method of preparing the nanofibers, the method comprising: (a) dissolving niobium chloride and potassium sorbate in a solvent to obtain a first solution; (b) removing chloride precipitates formed from the first solution; (c) adding a polymer, for example polymethylmethacrylate or polyvinylpyrrolidone to the solution to obtain a second spinnable solution; and (d) electrospinning the spinnable solution to produce the fibers. The application also discloses the application of such nanofibers in the manufacture of a humidity sensor device by sputtering a metal such as Tantalum on top of the nanofibers.

An antibacterial fiber that includes a plurality of charge generation fibers. The plurality of charge generation fibers generate electric charges with application of external energy thereto, and the space between the plurality of charge generation fibers is not uniform.

Provided is a piezoelectric substrate including: an elongate conductor; and an elongate first piezoelectric material helically wound in one direction around the conductor, in which the first piezoelectric material includes an optically active helical chiral polymer (A), the lengthwise direction of the first piezoelectric material and the principal orientation direction of the helical chiral polymer (A) included in the first piezoelectric material are substantially parallel to each other, and the first piezoelectric material has an orientation degree of F in a range of from 0.5 to less than 1.0, determined from X-ray diffraction measurement by the following Formula (a):

orientation degree F.=(180???)/180?(a)

(in Formula (a), ? represents a half width of a peak derived from orientation).

Methods and systems for sending multicast messages are disclosed. A multicast message is received to be transmitted to a plurality of access terminals at a radio access network (RAN), the received multicast message having a first format. The first format may correspond to a conventional multicast message format. The RAN determines whether the received multicast message requires special handling. If the RAN determines the received multicast message requires special handling, the radio access network converts the received multicast message from the first format into a second format. The RAN transmits the converted multicast message with the second format (e.g., a data over signaling (DOS) message) on a control channel to at least one of the plurality of access terminals. The access terminals receiving the converted multicast message interpret the message as a multicast message.

Piezoelectric vibrational energy harvesters (PVEHs) include a Macro Fiber Composite (MFC)) piezoelectric transducer coupled to a cantilever to harvest vibrational energy. One or more Ionic Polymer Metal Composite (IPMC) strips are situated to provide device tuning over a wide frequency range by applying variable contact force to the cantilever. Power consumption for tuning is sufficiently low that the tuning actuator (IPMCs) can be powered using harvested energy.

A piezoelectric fiber composite that includes a substrate having a first expansion and contraction rate, a piezoelectric fiber assembly having piezoelectric fibers that generate electrical charges upon application of external energy and has a second expansion and contraction rate different from the first expansion and contraction rate of the substrate, and a joint portion that joins the substrate and the piezoelectric fiber assembly.

Provided is a configuration capable of improving the signal strength of a piezoelectric element using piezoelectric fibers. This braided piezoelectric element comprises a core comprising conductive fibers and a sheath comprising braided piezoelectric fibers so as to cover the core, the braided piezoelectric element further comprising a metal terminal connected and fixed to the core in either of the following states A or B. A) A state where a portion of the metal terminal grasps a fiber portion constituting the end of a braided piezoelectric element and the core and the metal terminal are electrically connected to each other and fixed within 1 mm from where the metal terminal grasps the fiber portion. B) A state where: a portion of the metal terminal has a fork or needle shape; the fork-shaped or needle-shaped portion is electrically connected to the core while in contact with the sheath; and the braided piezoelectric element is secured to the metal terminal by another portion of the metal terminal or a component fixed to the metal terminal within 10 mm from the point of the electrical connection.