Abstract: Disclosed herein is an acoustic metamaterial structure which can effectively reduce noise in a specific frequency range through formation of an acoustic bandgap, wherein the specific frequency range is determined by a periodic structure formed by an array of multiple unit cells. The acoustic metamaterial structure includes multiple first unit cells each including a first space having a first cross-sectional area and a second space disposed downstream of the first space in a flow direction of fluid to communicate with the first space, the second space having a second cross-sectional area larger than the first cross-sectional area, wherein the acoustic metamaterial structure reduces noise in a specific frequency range through formation of an acoustic bandgap, the specific frequency range being determined by a periodic structure formed by an array of the first space and the second space.

Abstract: An ultrasonic transducer employing a meta slab includes a piezoelectric body configured to generate elastic waves; a meta slab connected to the piezoelectric body and configured to induce elastic wave mode conversion resonance with respect to the elastic waves incident on the meta slab; and a wedge connected to the meta slab, attached to an external surface of a pipe, and configured to transmit the elastic waves having passed through the meta slab to the pipe. The meta slab includes an anisotropic medium and a thickness of the meta slab satisfies the equation as follows: d=m·nFS·?FS/4, d=m·nSS·?SS/4, nSS/2?nFS/2=odd. Thus, highly-efficient flow velocity measurement is possible.

Abstract: A cover unit includes: a body to which an ultrasound generator adapted to generate ultrasound is coupled; first slits disposed at a lower portion of the body in the form of multiple rings having different radii and spaced apart from each other, the first slits having a first width; second slits depressed from an upper surface of the body to communicate with the first slits and having a second width smaller than the first width; third slits depressed from the upper surface of the body and each disposed between adjacent second slits, the third slits having a third width smaller than the first width; a bottom formed under the first slits; a first sidewall formed between adjacent first slits; and a second sidewall formed between the second slit and the third slit.

Abstract: A carrier substrate includes a base layer, an antireflection layer, and an energy absorption layer, wherein the antireflection layer is formed on one surface of the base layer and allows an elastic wave generated by a first laser beam transmitted through an element adhesively bonded to the antireflection layer to be transmitted through the base layer without being reflected towards the element, the first laser beam being applied to the element through a source substrate of the element, and the energy absorption layer is formed between the base layer and the antireflection layer to be aligned with the element, and evaporates upon energy absorption.

Abstract: Disclosed is an ultrasonic wave transmission structure which is provided on a path of ultrasonic waves to amplify incident ultrasonic waves. The ultrasonic wave transmission structure includes: multiple rings each provided with a body portion having a different radius from other body portions and spaced apart from another body portion adjacent thereto and a slit disposed between adjacent body portions; and a membrane disposed in the multiple rings, wherein the mass of the membrane is adjusted to vary a resonant frequency in multiple sub-membrane regions.

Abstract: An embodiment of the present invention provides an ultrasonic wave amplifying unit which can improve ultrasonic power in air, wherein the ultrasonic wave amplifying unit includes multiple rings having a concentric axis and each having a first width, and a slit having a second width is formed between the rings and an air layer is formed between the multiple rings and an ultrasonic wave generator generating ultrasonic waves or a transfer medium transferring the ultrasonic waves.

Abstract: A graphene manufacturing device using Joule heating includes: a chamber having a space provided therein so as to synthesize graphene; and a first roller portion and a second roller portion disposed inside the chamber to be spaced from each other such that same support a catalyst metal penetrating the interior of the chamber and are supplied with an electric current for graphene synthesis, thereby Joule-heating the catalyst metal. In order to compensate for a temperature deviation of the catalyst metal passing between the first roller portion and the second roller portion, a first area of the catalyst metal, which is close to the first roller portion, and a second area of the catalyst metal, which is close to the second roller portion, are disposed to have movement paths facing each other.

Abstract: A nanomaterial ribbon patterning method includes: forming a first nanomaterial layer having a first threshold strain on an upper surface of a substrate; forming a second nanomaterial layer on an upper surface of the first nanomaterial layer; forming a thin layer having a second threshold strain smaller than the first threshold strain on an upper surface of the second nanomaterial layer; generating plural cracks on the thin layer and the second nanomaterial layer by applying tensile force to the substrate; placing a mask on an upper surface of the thin layer; removing the mask and peeling off the sacrificial layer on the upper surface of the thin layer; and removing the sacrificial layer to form a nanomaterial ribbon pattern.

Abstract: One embodiment of the present invention provides an optical imaging apparatus using a metamaterial including a metamaterial array sensor which includes a plurality of unit cells made of a metamaterial and is positioned adjacent to an observation object, an imaging beam providing unit which provides an imaging beam toward the metamaterial array sensor, a control beam providing unit which controls a control beam provided to the unit cell to block the imaging beam incident on the unit cell, and an imaging beam measuring unit which measures a unit cell imaging beam transmission amount passing through the unit cell by measuring an imaging beam transmission amount of the metamaterial array sensor when the imaging beam passes through the unit cell and an imaging beam transmission amount of the metamaterial array sensor when the control beam is focused on the unit cell to block the imaging beam incident on the unit cell.

Abstract: In a meta-structure having multifunctional properties according to an exemplary embodiment of the present invention, a plurality of unit blocks controlling a property of a wave is combined on a plane or in a space in a predetermined pattern to form one structure, at least one of the plurality of unit blocks is formed to have a different size, and a frequency range of a wave controlled is changed according to the size of the unit block.

Abstract: A carrier film according to an embodiment of the present invention comprises: a base film; and a first adhesive layer formed on a surface of the base film such that an element to be transferred is attached to the first adhesive layer, wherein the magnitude of force of adhesion between the element and the first adhesive layer is in proportion to the depth of press-fitting at which the element is press-fitted into the first adhesive layer.

Abstract: An embodiment of the present invention provides an ultrasonic wave amplifying unit which can improve ultrasonic power in air, wherein the ultrasonic wave amplifying unit includes multiple rings having a concentric axis and each having a first width, and a slit having a second width is formed between the rings and an air layer is formed between the multiple rings and an ultrasonic wave generator generating ultrasonic waves or a transfer medium transferring the ultrasonic waves.

Abstract: The present invention relates to a carrier film for transferring a microelement, wherein, when a microelement is pressurized, a uniform pressurizing force is provided to the entire microelement, and a damage to the microelement can be prevented. The carrier film for transferring a microelement comprises: a load control layer having a first elastic modulus and having a space formed in a part of the interior thereof; and an adhesive layer having a second elastic modulus that is smaller than the first elastic modulus, the adhesive layer being provided on the upper portion of the load control layer and configured such that a microelement supposed to be transferred to a target substrate is attached thereto. The load control layer has a first zero-rigidity area that maintains a first stress in a first deformation range from a first strain to a second strain.

Abstract: Provided is a graphene production method using Joule heating, including: a catalytic metal placement step in which a catalytic metal is disposed on a pair of electrodes disposed inside a chamber; a gas supply step in which a carbon-containing reaction gas and a carrier gas for transporting the reaction gas are supplied into the chamber; a heating step in which the catalytic metal is rapidly heated to a temperature required for synthesis of graphene; a temperature maintenance step in which the temperature of the catalytic metal is maintained to form the graphene on the catalytic metal; and a cooling step in which the catalytic metal is cooled to prevent local occurrence of hotspots on the graphene formed on the catalytic metal, wherein the heating step, the temperature maintenance step, and the cooling step constitute one cycle of temperature control and the cycle is repeated for a predetermined process time.

Abstract: Provided are a graphene preparation apparatus, including: a chamber having a space for preparation of graphene; a first electrode and a second electrode disposed in the chamber to be separated a predetermined distance from each other, the first electrode and the second electrode supporting a catalytic metal and receiving electric current for preparation of the graphene to heat the catalytic metal using Joule heating; additional heaters disposed at opposite sides of the catalytic metal, respectively, and heating the catalytic metal to compensate for a temperature difference between both end regions and a central region of the catalytic metal heated using Joule heating induced by the first electrode and the second electrode; and a current supply unit supplying electric current to the first electrode and the second electrode.

Abstract: A nanomaterial ribbon patterning method includes: forming a first nanomaterial layer having a first threshold strain on an upper surface of a substrate; forming a second nanomaterial layer on an upper surface of the first nanomaterial layer; forming a thin layer having a second threshold strain smaller than the first threshold strain on an upper surface of the second nanomaterial layer; generating plural cracks on the thin layer and the second nanomaterial layer by applying tensile force to the substrate; placing a mask on an upper surface of the thin layer; removing the mask and peeling off the sacrificial layer on the upper surface of the thin layer; and removing the sacrificial layer to form a nanomaterial ribbon pattern.

Abstract: One embodiment of the present invention provides an optical imaging apparatus using a metamaterial including a metamaterial array sensor which includes a plurality of unit cells made of a metamaterial and is positioned adjacent to an observation object, an imaging beam providing unit which provides an imaging beam toward the metamaterial array sensor, a control beam providing unit which controls a control beam provided to the unit cell to block the imaging beam incident on the unit cell, and an imaging beam measuring unit which measures a unit cell imaging beam transmission amount passing through the unit cell by measuring an imaging beam transmission amount of the metamaterial array sensor when the imaging beam passes through the unit cell and an imaging beam transmission amount of the metamaterial array sensor when the control beam is focused on the unit cell to block the imaging beam incident on the unit cell.

Abstract: A method for transferring a micro device, includes: a compression step in which a carrier film having a micro-device attached to an adhesive layer thereof is brought into contact with a substrate comprising a solder deposited on metal electrodes formed on the substrate and is compressed on the substrate; a first adhesive strength generation step in which the solder disposed between the micro-device and the metal electrodes is compressed in the compression step to generate first adhesive strength between the micro-device and the solder; a second adhesive generation step in which the micro-device is bonded to the adhesive layer through press-fitting in the compression step to generate second adhesive strength between the micro-device and the adhesive layer; and a release step in which the carrier film is separated from the substrate, with the micro-device adhered to the solder.

Abstract: A transducer complex includes a resonator for enhancing an output and a measurement sensitivity of a guided wave transducer. The transducer complex includes: an ultrasonic transducer attached onto a surface or inserted into an object, the ultrasonic transducer having a longer length in parallel with the surface of the object than a length in a direction perpendicular to the surface of the object and the ultrasonic transducer receiving electric power from an external power source to generate ultrasonic waves or receiving ultrasonic waves from outside to generate electricity; and the resonator attached to the object or the ultrasonic transducer or inserted into the object, the resonator being symmetrically arranged in parallel on the outside of the ultrasonic transducer to be adjacent to the ultrasonic transducer.

Abstract: A method for transferring a micro device, includes: a compression step in which a carrier film having a micro-device attached to an adhesive layer thereof is brought into contact with a substrate comprising a solder deposited on metal electrodes formed on the substrate and is compressed on the substrate; a first adhesive strength generation step in which the solder disposed between the micro-device and the metal electrodes is compressed in the compression step to generate first adhesive strength between the micro-device and the solder; a second adhesive generation step in which the micro-device is bonded to the adhesive layer through press-fitting in the compression step to generate second adhesive strength between the micro-device and the adhesive layer; and a release step in which the carrier film is separated from the substrate, with the micro-device adhered to the solder.