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: A holographic-based directional sound device is provided, the device including: a sound wave generating means generating a sound wave; and a flat plate configured to have the sound wave generating means installed at the center so as to radiate the sound wave to the outside through a surface, and to be composed of a plurality of unit cells, in which at least one groove is formed on a surface of the unit cell, and a radiation angle of the sound wave is determined according to a depth of the groove with respect to the unit cell, wherein the depth of the groove is determined by an individual surface admittance calculated by a cosine function or a sine function of the sum of a first value and a second value on the basis of a preset radiation angle of the sound wave and a preset frequency of the sound wave.

Abstract: The present invention relates to a metal-organic framework and an energy storage system having the same, and more specifically, to an energy storage system that is capable of providing excellent electrical conductivity and electrochemical capacity properties, especially excellent electrochemical performance at low temperatures, by means of a novel one-dimensional metal-organic framework having thianthrene-based organic ligands.

Abstract: A sound insulation plate includes a patterned frame and an elastic membrane, wherein the patterned frame includes a central pattern region and multiple peripheral pattern regions arranged around the central pattern region, the multiple peripheral pattern regions being separated from the central pattern region by a separation bar, and wherein the elastic membrane is mounted on the patterned frame to block passage of air and converts airborne sound waves into elastic waves.

Abstract: Proposed are a stretchable display panel device capable of effectively correcting an image according to a strain ratio and a method of correcting the image. The stretchable display panel device includes a stretchable display panel, a measurement unit, and a correction unit. The measurement unit measures the strain ratio of the stretchable display panel. The correction unit corrects the image on the stretchable display panel on the basis of the strain ratio. The expandable and contractible display panel overall has a uniform strain ratio and has a negative effective Poisson’s ratio. The strain ratio is a strain ratio in a first direction.

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: The present invention relates to a metal-organic framework and an energy storage system having the same, and more specifically, to an energy storage system that is capable of providing excellent electrical conductivity and electrochemical capacity properties, especially excellent electrochemical performance at low temperatures, by means of a novel one-dimensional metal-organic framework having thianthrene-based organic ligands.

Abstract: An embodiment of the present invention provides a stretchable substrate allowing various pitch control for a device thereon, and a method of controlling a device spacing using the same. Here, the stretchable substrate includes a cell and an electrode wiring. The cell is divided by cutting lines to form a plurality of cells. The electrode wiring is continuously provided on the plurality of cells not to cross the cutting line. A cell is connected to a neighboring cell by a connection portion in which a cutting line is not formed, and when a tensile force is applied, the cell is hinge-rotated around the connection portion, and the electrode wiring maintains a continuous state even when the cell is hinged.

Abstract: An embodiment of the present invention provides a stretchable substrate that may be significantly stretchable to be deformed but have a low rate of breakage. Here, the stretchable substrate includes a cell, a cut portion, and an extended cut line. A plurality of cells are formed in the substrate body, and a device is mounted thereon. The cut portion is formed in the substrate body to increase a distance between the cells when the substrate body is stretched. The extended cutting line is formed to extend from an end portion of the cut portion and bent inwardly of the cell so that corners of the cells are rounded.

Abstract: A method, an apparatus, and a system for recommending a location of a charging station of a robot are disclosed. The method includes obtaining movement path information from one or more robots in a space including a plurality of regions, determining density of each of the plurality of regions based on the obtained movement path information, and determining a recommended location of a charging station for charging the one or more robots from the plurality of regions based on the determined density. In a 5G environment connected for the Internet of things, the method for recommending a location of a charging station is implemented by executing an artificial intelligence algorithm or machine learning algorithm.

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: Disclosed herein is a meta-muffler for reducing broadband noise. The meta-muffler includes: a flow pipe through which a fluid flows; an outer barrel disposed outside the flow pipe to be spaced apart from the flow pipe; and multiple metastructures arranged in a flow direction of the fluid and each comprising an opening opened parallel to the flow direction of the fluid, a resonance chamber disposed between the flow pipe and the outer barrel and communicating with the flow pipe through the opening, and a neck adjustment member extending from the outer barrel toward the flow pipe to be spaced apart from the opening in the flow direction of the fluid. The meta-muffler can increase transmission loss of noise flowing through the flow pipe through maximization of energy loss of sound waves entering the resonance chamber of the metastructure and can effectively attenuate noise over a wide band ranging from low frequencies to high frequencies.

Abstract: An apparatus for repairing elements, includes: a bonding material transfer stamp transferring a new bonding material to a repair area on a substrate, the repair area having a defective element or a residual bonding material removed therefrom; and an element transfer stamp transferring a new element to the new bonding material, wherein the element transfer stamp comprises a load control portion for elements, the load control portion being bent and deformed upon receiving pressing force such that a zero-stiffness load smaller than a critical damage load of the new element is applied to the new element.

Abstract: Disclosed herein are a metastructure having a zero elastic modulus zone, which can experience constant stress in a predetermined strain zone, and a method for designing the same. The metastructure includes a first unit and a second unit, wherein the first unit has a structure capable of buckling and has a stress-strain relation having a zone corresponding to a negative elastic modulus, the second unit is disposed adjacent to the first unit and has a stress-strain relation having a zone corresponding to a positive elastic modulus, and the metastructure has zero elastic modulus in a predetermined target strain zone through synthesis of the negative elastic modulus of the first unit with the positive elastic modulus of the second unit.

Abstract: A sound insulation plate includes a patterned frame and an elastic membrane, wherein the patterned frame includes a central pattern region and multiple peripheral pattern regions arranged around the central pattern region, the multiple peripheral pattern regions being separated from the central pattern region by a separation bar, and wherein the elastic membrane is mounted on the patterned frame to block passage of air and converts airborne sound waves into elastic waves.

Abstract: An embodiment of the present invention provides an element transferring method that may increase a yield of transferring an element, and an electronic panel manufacturing method using the same. The element transferring method includes: preparing a carrier film in which a first surface of an element on which a terminal is formed is adhered to an adhesive surface; providing a cover adhesive layer on the adhesive surface so that the second surface of the element that is opposite to the first surface and where the terminal is not formed is covered; transferring the element to the target substrate by adhering the cover adhesive layer to the target substrate while the second surface is facing the target substrate; and separating the carrier film from the element, wherein in transferring the element, the carrier film is pressed so that the surface of the cover adhesive layer is flat at the same height as the terminal.

Abstract: Disclosed herein are a non-rigid pad for device transfer, which allows uniform contact pressure to be applied between multiple devices and a target substrate to which the devices are to be transferred, a method of manufacturing the same, and a non-rigid pad group for device transfer including the same. The non-rigid pad includes: a base plate; and multiple pillars each protruding from one surface of the base plate with one end thereof connected to the one surface of the base plate, the pillars being bent and deformed upon application of external force, wherein the non-rigid pad is disposed between a transfer film to which multiple devices to be transferred to a target substrate are adhesively attached and a pressing unit providing pressing force to transfer the multiple devices to the target substrate, the non-rigid pad being bent and deformed upon application of pressing force by the pressing unit to allow uniform contact pressure to be applied between the multiple devices and the target substrate.

Abstract: The present disclosure relates to a two-dimensional Ni-organic framework/rGO composite including: a two-dimensional electroconductive Ni-organic framework in which Ni and an organic ligand containing a substituted or unsubstituted C6-C30 arylhexamine are repeatedly bonded in a branched form; and reduced graphene oxide (rGO). Thus, when a composite of reduced graphene oxide (rGO) and a two-dimensional Ni-MOF is prepared and used as an energy storage electrode material, the two-dimensional Ni-organic framework/rGO composite of the present disclosure can exhibit higher discharge capacity per weight due to the synergistic effect of rGO and Ni-MOF as compared to when Ni-MOF is used alone, and the composite can be used to manufacture a thin-film type electrode, which can be used as a next-generation energy storage electrode having high mechanical bending strength and energy density per volume.

Abstract: A holographic-based directional sound device is provided, the device including: a sound wave generating means generating a sound wave; and a flat plate configured to have the sound wave generating means installed at the center so as to radiate the sound wave to the outside through a surface, and to be composed of a plurality of unit cells, in which at least one groove is formed on a surface of the unit cell, and a radiation angle of the sound wave is determined according to a depth of the groove with respect to the unit cell, wherein the depth of the groove is determined by an individual surface admittance calculated by a cosine function or a sine function of the sum of a first value and a second value on the basis of a preset radiation angle of the sound wave and a preset frequency of the sound wave.

Abstract: A transparent stealth structure includes: a first transparent film structure stacked on a front surface of a transparent base, the first transparent film structure causing energy loss of incident electromagnetic waves having a target frequency to change a phase of transmitted electromagnetic waves propagating toward the transparent base; and a second transparent film structure stacked on a back surface of a transparent base, the second transparent film structure reflecting the transmitted electromagnetic waves having passed through the transparent base while adjusting a phase of reflected waves propagating toward the first transparent film structure, wherein the first transparent film structure includes a first front transparent conductive pattern having a first sheet resistance and a second front transparent conductive pattern filling a region, and the second transparent film structure includes a first rear transparent conductive pattern having a third sheet resistance and a second rear transparent conductiv