baber/WOPTO huggingface dataset:
Patent KR-20000030946-A (KR)
Title: Sputtering equipment
Inventor: KIM DAE KWANG
IPC: H01L21/205
Filed: 1998-10-20
Abstract: PURPOSE: A sputtering equipment is provided to extend the life span of a metal target by consuming the metal target as a metal source in a metal process at the same rate over the whole area. CONSTITUTION: A sputtering equipment(100) is composed of an entrance chamber(10) temporarily waiting for a process before a wafer or an LCD glass processes a process, a process environment formation chamber(20) where a process environment is firstly formed, a processor chamber(30) in which a sputtering process is processed, a cooling chamber(40) installed to prevent a crack from generating on a metal thin film coated while the LCD glass is quickly cooled and a discharging chamber(50) temporarily waiting before the cooled wafer or LCD glass is discharged. Herein, a vacuum pressure generator(60) is installed for forming vacuum pressure in the entrance, process environment formation, cooling and discharging chambers. In addition, the processor chamber is installed with a cathode(34) attached with the metal target on a front face needed to form a plasma, a device for increasing the density of the plasma, a regulator of the amount of target consumption to prevent the metal target from unequally being consumed and a plasma gas supplier(31).
Patent KR-20000027222-A (KR)
Title: Phase shift mask for manufacturing semiconductor
Inventor: KIM MUN SIK
IPC: H01L21/027
Filed: 1998-10-27
Abstract: PURPOSE: A phase shift mask for manufacturing semiconductor is provided to enhance the reliability of the mask by judging the state of the mask in no relation with the size of a semiconductor device, and to increase phase detection speed by storing test pattern. CONSTITUTION: A phase shift mask for manufacturing semiconductor comprises a chrome film(3), a shifter(2), a quartz substrate(1), and plural test patterns(4). The chrome film selectively transmits light. The shifter generates a phase shift to the light transmitted through the chrome film. The quartz substrate supports the shifter. The test pattern consists of a transmission area and a phase shift generation area. The transmission area is opened in the size in which can detect the chrome film formed on a mask in an area which isn't defined on a wafer. In the phase shift generation area, hole is formed.
Patent KR-19990044979-A (KR)
Title: 내장형 전기 플래시를 구비한 일회용 카메라
IPC: G03B15/05
Filed: 1998-11-03
Abstract: 내장형 전기 플래시를 구비한 일회용 카메라에 있어서, 본체; 상기 본체에 미리 장전된 사진 필름; 전기 플래시 발광부와 전기 플래시 회로를 갖는 전기 플래시 유닛; 및 촬영 렌즈와 셔터를 갖는 촬영 유닛을 포함하고, 다음의 조건식 
     6 ≤ A ≤ 10 
     을 만족하며, 여기서 A는 전기 플래시 유닛이 사용된 조건에서 촬영할 때, 렌즈 구경값(aperture value), 셔터 속도 및 일회용 카메라 내에 장전된 필름의 감도에 의해서 결정된 노출광량의 값(exposure value)을 나타낸다.
Patent KR-20000032683-A (KR)
Title: Blue light-emitting luminous polymer fabricated with tetraphenyl derivative bearring fluoride substituent as monomer and electroluminescent device using the same
Inventor: HWANG DO HUN
IPC: C08G61/10
Filed: 1998-11-17
Abstract: PURPOSE: A blue light-emitting luminous polymer fabricated with a tetraphenyl derivative barring a fluoride substituent as monomer is provided to improve hole injection and transport as well as electron injection and transport and to emit blue light. An electroluminescent device is provided to achieve efficient light output. CONSTITUTION: A blue light-emitting luminous polymer comprises four pi-phenylene rings barring fluoride substituents and an arylenvinylene unit. The pi-phenylene rings and an arylenvinylene unit repeat orderly. A tetraphenyl derivative barring a fluoride substituent comprises a monomer which is fabricated by substituting phosphonate or phosphonium salt for halogen group of the bistetraphenyl derivative barring a fluoride substituent. An electroluminescent device comprises a substrate(1), a translucent electrode(2) on the substrate(1), a luminous polymer layer(4) formed with a blue light-emitting luminous polymer and metal electrode(6). Alternatively, the luminous polymer layer(4) is formed between a hole transfer layer(3) and an electron transfer layer(5).
Patent KR-20000032818-A (KR)
Title: Method for manufacturing a pyroelectric device for detecting thermal image
Inventor: KIM TAE HUN
IPC: H01L31/00
Filed: 1998-11-18
Abstract: PURPOSE: A method for manufacturing a pyroelectric device for detecting thermal image is provided to separate semipermeable membrane from glass without failure in process. CONSTITUTION: A method for manufacturing a pyroelectric device for detecting thermal image comprises forming many grooves at front side of a dielectric layer by partially selective etching, selectively forming etch stopper layers only in the grooves, forming a lamination structural layer on the front side of the dielectric layer and the etch stopper layer, wherein the lamination structural layer consisting of a first metal electrode(106), infrared absorption layer(108) and semipermeable membrane(110), forming many optional layer pattern(112) on the lamination structural layer to expose the surface of the semipermeable membrane(110) on the etch stopper layer, attaching glass(116) on the lamination structural layer by adhesive(114), forming dielectric layer pattern(100a) by polishing the back of the dielectric layer until the etch stopper layer is exposed, selectively forming many a second metal electrode(118) only on the back of the dielectric layer, removing the etch stopper layer in the grooves, separating each pixel or array element by sawing, providing a semiconductor chip(150) having a mesa insulation layer(152) and a third metal electrode(154), flip-chip bonding the third metal electrode(154) and the second metal electrode(118) by indium bump(170), and separation of the lamination structural layer from glass(116) by chemical solution.
Patent KR-20000033876-A (KR)
Title: Method of repeatedly reproducing caption interval in video cassette recorder
Inventor: PARK DEOK CHAN
IPC: G11B20/00
Filed: 1998-11-26
Abstract: PURPOSE: A method of reproducing a caption interval is provided to be capable of repeatedly reproducing only a caption signal by providing a key input unit with a caption unit. CONSTITUTION: A method of reproducing a caption interval comprises the steps of: inserting a video tape into a VCR; reproducing the video tape; determining if a caption selection key is inputted; performing a rewind mode if the caption selection key is determined to be inputted; deciding whether a caption signal is detected, while performing the rewind mode; repeatedly reproducing the caption signal when the caption signal is determined to be detected; and determining whether a reproduction mode is completed when the caption selection key is determined not to be inputted. If not, performing the reproducing step, and if so, terminating the reproducing step.
Patent KR-20000039983-A (KR)
Title: Method for implementing database in intelligent network scp system
Inventor: LEE SANG WOO
IPC: G06F17/30
Filed: 1998-12-16
Abstract: PURPOSE: A method for implementing a database in an intelligent network SCP system is provided to decrease a searching time by composing the method as a distributed tree structure. CONSTITUTION: A tree figure witch wants to be distributed is determined when constructing a database of an intelligent network service control system(ST1). A key value is divided and a share is collected to form a group of a key for having a number of desired tree, and then a tree is distributed using the group of the key as an index of the tree(ST2,ST3). An index by the group of the key is searched to search a tree, and data is read(ST4).
Patent KR-20000017676-A (KR)
Title: Cock valve for pipe of water purifier
Inventor: CHOI MIN CHEOL
IPC: F16K5/00
Filed: 1998-12-23
Abstract: PURPOSE: A cock valve for pipe is provided to reduce producing cost and to make convenient the assembling work by reducing the numbers of components by changing the combining structure of a switching valve and a rotating cam and to make smooth the forming work of a cock valve by forming a closed ring on the outer wall of the switching valve. CONSTITUTION: A cock valve for pipe is used by the steps of: forming a closed ring(300) on the outer wall of a switching valve(20); inserting the switching valve to a rotating place(11) formed in the center of a body(10); combining a fixing groove(23) on the switching valve with a fixing protrusion(33) of a rotating cam(30), then a hanging protrusion(14) is positioned in the gap of a hanging sill(32), and a combining hole(202) of the rotating cam and a combining hole(201) of the switching valve are accorded in vertical; tightening the combining holes by using a combining member(200) to adhere an adhering part(300) to the upper part of the switching valve and to fix the switching valve on the rotating place; positioning a cock valve(A) on a place to be fixed after the combining is completed; and fixing the cock valve by combining a fixing member to a fixing groove(401) on a fixing piece(400).
Patent KR-20000043615-A (KR)
Title: Line interpolation apparatus and method using line memory
Inventor: KO DO YOUNG
IPC: H04N7/01
Filed: 1998-12-29
Abstract: PURPOSE: A line interpolation apparatus is provided to perform a precise interpolation close to an original signal by executing a line interpolation through the selection with the most appropriate line interpolation method. CONSTITUTION: A vertical high pass band filter(101) calculates a high frequency component of a vertical direction of pixels constituting a video signal. A high frequency component detector(102) compares an output signal of the vertical high pass filter(101) with a reference signal corresponding to a cutoff frequency to detect a high frequency component signal over the reference signal. A counter(103) counts th number of the high frequency component signals outputted from the high frequency component detector(102). A latch(104) temporarily stores the counting values of the counter(103).
Patent KR-20000044467-A (KR)
Title: Method for transmitting data in cellular telephone
Inventor: KIM JONG MYEONG
IPC: H04B1/38
Filed: 1998-12-30
Abstract: PURPOSE: A method for transmitting a data in a cellular telephone is provided to transmit a data stored in a Compact Disk Read Only Memory(CD-ROM) through a Compact Disk player. CONSTITUTION: A method for transmitting a data in a cellular telephone with a compact disk connector and a data processor, comprises the steps of: displaying data's contents on a displayer by reading a data stored in a Compact Disk Read Only Memory(CD-ROM); selecting the displayed file, according to a selecting key received from a key input circuit; dialing after selecting the data; and transmitting the selected data into a wireless signal through a wireless circuit after being connected a speech path. The Compact Disk(CD) connector can connect with a Compact Disk(CD) player. The data processor reads and processes a data from the CD connector.
Patent KR-20000044821-A (KR)
Title: Thin film micromirror array-actuated device with fold
Inventor: KIM MYUNG JIN
IPC: G02F1/015
Filed: 1998-12-30
Abstract: PURPOSE: A TMA device with fold is provided to reduce the stress put on the actuator and to reduce the voltage needed to maintain the transformation of the actuator by extending the piezoelectric part. CONSTITUTION: A device comprises an active matrix(5), a drain pad(10), a membrane(30, 130), a lower electrode(35, 135), an electroplasive(40, 140), an upper electrode(45, 145), an actuator(65, 165), a fixing end(61), a free end(62, 162), a mirror post(70b), and a mirror(75). The active matrix comprises a semiconductor like silicon and a plurality of MOS transistors. The drain pad(10) which is electrically connected with the drain electrode of the MOS transistor id formed on one end of the active matrix. The actuator includes the membrane, lower electrode, electroplasive, and the upper electrode. The drain pad and the upper electrode is electrically connected with fixing end. The mirror post is formed on the free end of the actuator and the mirror is supported by the mirror post. Furthermore, the free end of the actuator is formed to have folds.
Patent KR-19990087651-A (KR)
Title: 다기능 이동 전화 스테이션
IPC: H04W88/02
Filed: 1997-03-04
Abstract: 제1횡단-연결 기본-대역 스위치 시스템(370A, 370B) 및 제2횡단-연결 기본-대역 스위치 시스템(365A, 365B)으로써 실행된 스위칭 회로를 갖는 적어도 하나의 공중 지상 이동망과 관계된 다기능 이동국(MMS)(610B). 제1횡단-연결 기본-대역 스위치 시스템(370A, 370B)은 외부 수신기 및 송수신기와 MMS의 마이크로폰중 적어도 하나간에 제1연결을 선택 가능하게 이룬다. 제2횡단-연결 기본-대역 스위치 시스템(365A, 365B)은 외부 송신기 및 송수신기와 MMS(610B)의 스피커(350)중 적어도 하나간에 제2연결을 선택 가능하게 이룬다. MMS(610B)는 제1연결을 설정하는 하나의 출력 노드(335) 및 제2연결을 설정하는 하나의 입력 노드(340)를 포함하도록 사용된다.
Patent KR-20000011081-A (KR)
Title: Method and equipment for treating electrostatic field and electrode used therein
Inventor: ITO AKINORI
IPC: A23L3/365
Filed: 1998-03-17
Abstract: PURPOSE: A method for treating electrostatic field, its equipment and an electrode using therein are provided which are safe and can impress voltage to oil even if the output voltage of second side of a transformer is relatively low. CONSTITUTION: An electrode plate(37) is located in a refrigerator, while being insulated from the inner wall of the refrigerator(30), and an object of treatment(35) is placed on the electrode plate(37), also while being insulated from the inner wall of the refrigerator, followed by the application of a voltage suitable for food to the same. A high voltage generator used for this purpose is provided with safety devices for preventing the flow of a current exceeding a specified value. In a fryer, an electrode is inserted into an oil container and a voltage of 500-700 V is applied to the electrode while leaving a fryer case ungrounded.
Patent KR-20000016395-A (KR)
Title: Amide derivatives
Inventor: OKAMURA TAKASHI
IPC: C07D487/04
Filed: 1997-06-02
Abstract: PURPOSE: New amide derivatives are provided which are useful as analgetic agents, anti-inflammatory agents, antimicrobial agents, hypoglycemic agents, lipid lowering agents, hypotensive agents, and carcinoma agents. CONSTITUTION: Amide derivatives represented by general formula (1) and being useful as analgetic agents, anti-inflammatory agents, antimicrobial agents, hypoglycemic agents, lipid lowering agents, hypotensive agents, carcinoma agents, etc., wherein the ring A represents a benzene, naphthalene, pyridine or furan ring; R4 represents a heterocycle such as lower alkyl substituted thieno£3,2-d|pyrimidine-4-yl, optionally substituted pyrazolo£1,5-a|-1,3,5-triazine-4-yl, 6-substituted pyrazolo£3,4-d|pyrimidine-4-yl or 2-substituted purine-6-yl; and R5 represents hydrogen or a group represented by general formula (a) are described.
Patent KR-20000051743-A (KR)
Inventor: LEE IN HWAN
IPC: A47J27/00
Filed: 1999-01-26
Abstract: PURPOSE: An electric rice cooker is provided. CONSTITUTION: An electric rice cooker is provided with a plurality of and a different size of cylindrical can-shaped regions (11); heat wires (13) placed in the bottom of the cylindrical can-shaped regions (11); and a plurality of inner lids (21) which are placed in the inner side of a lid (24) joined with a body (10) by a hinge (20a). Internal vessels (12) are inserted into the cylindrical can-shaped regions (11), respectively. Only the specific internal vessel is heated by applying power to a heat wire (13) selectively.
Patent KR-20000051977-A (KR)
Inventor: PARK JONG YOUNG
IPC: H04B7/216
Filed: 1999-01-28
Abstract: PURPOSE: A method of demodulating and decoding reverse direction common channel is provided to minimize the collision between messages in case of transmitting many access messages through the reverse direction common channel. CONSTITUTION: A method of demodulating and decoding reverse direction common channel comprises the steps of: deciding and allocating fingers(120) on the large number of transmitted messages through access channel; comparing the PN offset of the above messages, allocating available demodulation route; demodulating message to the allocated route; decoding(190) in the border area of each frame in the above demodulation route by using the information on the frame border of the allocated demodulation route.
Patent KR-19990045875-A (KR)
Title: 폐수처리조성물및그의제조방법
Filed: 1999-02-03
Abstract: 본 발명은 폐수처리조성물 및 그의 제조방법에 관한 것으로, 화석탄 50∼85중량%, 벤토나이트(bentonite) 5∼15중량%, 산성 백토(酸性白土) 8∼12중량%와 나머지 양의 흡착제 및/또는 산화제 등으로 이루어짐으로써, 기존의 폐수처리제 보다 간단하고 저렴한 비용으로 각종 폐수 및 쓰레기 침출수 등의 COD, 색도 및 n-헥산과 계면활성제를 한단계의 처리로 일시에 함께 제거할 수 있으며, 폐수 성상에 따라 간단히 상기 성분의 함량이 조정될 수 있고, 별도의 시설이 필요 없을 뿐만아니라 처리 가능한 pH 범위가 광범위하므로 작업하기가 용이하고 지속적인 유화파괴효과가 있어 처리수의 수질을 향상시켜 폐수처리 시 실제 탁월한 효과를 발휘한다.
Patent KR-20000055558-A (KR)
Inventor: KIM MIN GU
IPC: H01L21/66
Filed: 1999-02-08
Abstract: PURPOSE: A connecting apparatus of a semiconductor is to improve a leakage current characteristic by eliminating a bud cage. CONSTITUTION: A connecting apparatus comprises a test head(110), a probe card(120), and a supporting frame(130). The test head is connected to a main tester(200) through three signal lines, two signal lines being for transferring a test signal opposite to each other and the remainder signal line being for transferring a guide signal. The test and guide signals inputted in the test head through the signal lines is switched the probe card through a pogo pin positioned under the test head. To this end, A contacting surface is formed in a pattern on an upper surface of the probe card. The test signal transferred to the probe card is transferred to a wafer to be tested. The probe card is rotatively supported by the supporting frame.
Patent KR-20000060468-A (KR)
Inventor: CHOO GYO SEOP
IPC: G02F1/133
Filed: 1999-03-16
Abstract: PURPOSE: A liquid crystal display panel is provided to be capable of suppressing a generation of a stitching stain and of increasing a free degree of a design through a simple array arrangement change. CONSTITUTION: A liquid crystal display panel comprises a pixel(100) including red, green and blue patterns and a pixel pattern having a plurality of pixels arranged in N rows and M columns (M is more than N). The liquid crystal display panel further comprises M gate lines(G1,G2-GM) for supplying current in a column direction, Nx3 data lines(D1,D2-DNx3) for supplying current to the red, green and blue patterns, a scan driving part(300) connected to the gate lines to generate a gate signal, and a data driving part(200) connected to the data lines to generate a data signal.
Patent KR-19990077939-A (KR)
Title: 강유전체기억장치
IPC: G11C14/00
Filed: 1999-03-16
Abstract: 강유전체 기억 장치는, 플레이트선 구동 회로, 더미 플레이트선 구동 회로, 정전압 발생 회로 및 가변 전압 발생 회로를 구비하고 있다.  상기 플레이트선 구동 회로는 데이터의 판독 시에, 선택된 메모리셀에 대응한 플레이트선을 펄스 구동한다.  상기 더미 플레이트선 구동 회로는 상기 선택된 메모리셀이 접속된 비트선과 상보 쌍을 이루는 기준용의 비트선에 접속된 더미셀에 대응한 더미 플레이트선을 펄스 구동한다.  상기 정전압 발생 회로는 외부 전원 전압이나 온도에 의존하지 않는 실질적으로 일정한 전압을 발생시켜, 상기 플레이트선 구동 회로에 전원으로서 공급한다.  상기 가변 전압 발생 회로는 외부 전원 전압이나 온도에 의존하지 않는 복수의 실질적으로 일정한 전압을 발생시켜, 비트선의 고레벨과 저레벨에 따라서 복수의 전압 레벨 중에서 선택한 전압을 상기 더미 플레이트선 구동 회로에 전원으로서 공급한다.
Patent KR-20000065987-A (KR)
Inventor: KIM SANG IN
IPC: H01J9/26
Filed: 1999-04-12
Abstract: PURPOSE: A coupling method of front/rear panels of a PDP is provided to reduce discharge voltage and thus increase PDP quality by performing activation process on a dielectric protective layer before coupling of panels and reduce process time by quick heating and vacuum ultraviolet treatment. CONSTITUTION: A front panel is supplied and activated by changing a dielectric protective layer into single crystal state by heating the surface up to 600 to 700°C by using infrared lamp. A rear panel is preheated. The activated front panel and the preheated rear panel are tacked together, and then coupled by heating up to 450°C and maintaining the temperature. A cooling and exhausting are performed to clean pollution gas absorbed on the dielectric protective layer. Discharge gas is injected into the PDP, and sealing and cooling up to the room temperature is performed.
Patent KR-20000066274-A (KR)
Inventor: JANG YEON SIK
IPC: G07D3/00
Filed: 1999-04-15
Abstract: PURPOSE: An apparatus for identifying counterfeit is provided to exactly identify various sized notes, and easily replace ROM storing information of a new note and a new counterfeit from a main PCB(printed circuit board). CONSTITUTION: The apparatus for identifying a counterfeit comprises a lower frame(10) in which a main PCB is mounted and a base cover(12) is attached to a lower end thereof; an upper conveying unit(20) mounted at an upper portion of the lower frame by a mounting and removing hinge(23) to have a plurality of note inserting ports; a driving unit comprised of a motor(30), a first to third conveying roller(41-43) rotated by driving force of the motor transmitted through a driving belt(37), a first conveying belt(38) and a second conveying belt(39), and a first to third idler(41'-43') disposed to be opposite to the first to third conveying roller to press a note; a sensor unit having an entering sensor(50,50') for detecting an inserting state of the note from the note inserting ports, a discharging sensor(51,51') for detecting a discharging state of the note and a plurality of note detecting sensors disposed between the entering and discharging sensors to detect various information of the note moved along the first and second conveying belt; a removable mounting unit for mounting ROM storing various data of the note in the base cover.
Patent KR-20000022615-A (KR)
Inventor: YIM BYUNG JIN
IPC: G06F1/16
Filed: 1999-04-16
Abstract: PURPOSE: A computer including an internal rack is provided to enhance the convenience and durability by keeping and using the mouse safely and easily without installing extra rack. CONSTITUTION: A computer comprises a main body(10), a rack(12), a cover(13), a hinge(14), and a guide(15). A housing(10a) for keeping the mouse(M) is formed at the entire main body(10). The housing blocks the alien materials from penetrating and the housing should be designed in a minimum size to fit the mouse. The rack is installed at the housing of the main body. The rack is formed in drawer type to prevent the mouse from moving or being detached and to be used conveniently. The mouse is directly connected to the main body of the computer internally. The mouse is installed at the rear end of the housing to block the mouse from contacting other important parts of the main body.
Patent KR-19990083463-A (KR)
Title: 다리미
IPC: D06F75/26
Filed: 1999-04-24
Abstract: 다리미는 누적된 열의 양을 증가시키기 위해 직접 가열되는 제 1 베이스와, 다림질 면을 구비하는 제 2 베이스와, 제 1 베이스와 제 2 베이스 사이에 배치된 열 저항 층을 포함한다.  열 저항 층은 제 1 베이스보다 큰 열 저항을 가짐으로써, 히터에 의해 가열된 제 1 베이스가 제 2 베이스보다 높은 온도를 유지할 수 있다.  본 발명의 다리미는 누적된 열의 양을 증가시킴으로써, 다림질 시간을 연장시킬뿐만 아니라 스팀 분무 시간도 연장된다.  다리미의 중량이 감소되면, 다리미는 통상의 다리미에 대해서 대략 동일하게 누적된 열을 유지함으로써, 경량의 다리미가 제공될 수 있다.
Patent KR-20000067251-A (KR)
Inventor: KIM SEUNG GU
IPC: E04B2/82
Filed: 1999-04-26
Abstract: PURPOSE: A support frame for fixing a partition is provided to reduce the term of work and the cost of manufacturing by forming a guide hole in the movable frame directly and lifting the frame using control part. CONSTITUTION: In the support frame for fixing a partition, one side of fixed frame(10) is fixed in the floor by anchor bolt, and the fixed frame contains a movable frame(30) in the inside. In the movable frame, an insert groove(31) is formed to support the lower part when the partition moves, and a guide hole(100) is installed in the lower part of movable frame, and a control part(200) that controls the height is bound with the guide hole. In the control part, a body(210) that has spiral is formed, and a head part(220) that has a control hole(221) is formed in the upper part body.
Patent KR-19990046817-A (KR)
Title: 컬러문양및사진이전사나염된당구천제조방법
IPC: D06P5/00
Filed: 1999-04-16
Abstract: 본 발명은 전사나염 방법에 관한 것으로, 전사될 컬러문양 및 사진을 편집하여 승화성염료로 이루어지는 전사체를 형성하는 제 1 과정과; 상기 전사체를 당구천위에 올려놓는 제2과정과; 상기 전사체 상면에 다공성 테프론시트를 위치시키고 열프레스로 압착시켜 약 180℃ 내지 200℃정도의 열을 가하여 약 1 내지 2분간 가압,가열하거나 또는 수평터널식전사기에 통과시켜 매개체 표면에 전사잉크가 승화에 의해 전사날염되도록 하는 제3과정으로 이루어져 당구천의 표면상에 칼라문양이나 사진 등의 전사나염 방법을 제공한다.  따라서, 본 발명에 따르면, 합성섬유로 이루어진 당구천 면위에 별도의 도막을 형성하지 않고도 간단하게 다양한 문양을 소량 다품종으로 전사나염시킬 수 있는 잇점이 있다.