baber/WOPTO huggingface dataset:
Patent KR-20160135171-A (KR)
Inventor: KIM KIJUN
IPC: H04L5/00
Filed: 2015-03-19
Abstract: 본 발명의 일 실시예는, 무선통신시스템에서 단말이 D2D(Device-to-Device) 신호를 전송하는 방법에 있어서, 시퀀스 그룹을 결정하는 단계; 상기 시퀀스 그룹에서 사용할 베이스 시퀀스를 결정하는 단계; 상기 베이스 시퀀스에 순환 이동을 적용하여 참조신호 시퀀스를 생성하는 단계; 상기 참조신호 시퀀스로부터 복조참조신호 시퀀스를 생성하는 단계; 및 상기 복조참조신호 시퀀스가 매핑된 서브프레임을 전송하는 단계를 포함하며, 상기 시퀀스 그룹의 결정, 상기 베이스 시퀀스의 결정 또는 상기 순환 이동의 적용 중 하나 이상에서 사용되는 ID 정보는, SSID(synchronization ID) 또는 시간에 따라 변경되는 L1 ID(Layer 1 ID) 중 어느 하나인, D2D 신호 전송 방법이다.
Patent KR-20160124901-A (KR)
Title: Pcsk9 백신
Inventor: GALABOVA GERGANA
IPC: C07K16/40
Filed: 2015-02-23
Abstract: 본 발명은 생체 내에서 PCSK9에 관한 항체의 생산을 유도할 수 있는 백신에 관한 것이다.
Patent KR-20160130801-A (KR)
Title: 다수의 플라즈마들 내의 프로세스 가스의 순환에 의한 플라즈마 처리 장치
Inventor: SCHLEMM HERMANN
IPC: H01J37/32
Filed: 2015-03-03
Abstract: 본 발명에 따른 플라즈마 처리 장치는, 처리 챔버―프로세스 가스가 그것을 통해 유동하는 적어도 2 개의 플라즈마 처리 구역들, 이 적어도 2 개의 플라즈마 처리 구역들에 프로세스 가스를 공급하기에 적합한 가스 유입구, 처리 챔버로부터 배기 가스를 배출하기에 적합한 가스 유출구를 가짐―뿐만 아니라, 순환 라인 및 순환 펌프를 갖는 순환 유닛―이 순환 유닛은 배기 가스의 적어도 일부분을 가스 유입구로 공급하기에 적합하며, 가스 유입구 내로 공급되는 배기 가스는 플라즈마 처리 구역들 중 적어도 2 개로부터 배출되는 가스들의 혼합물임-으로 구성된다.  플라즈마 처리 구역들 중 적어도 2 개로부터의 배기 가스들의 혼합, 및 가스 유입구 내로의 그들의 재생 공급 때문에, 이미 변환된 적어도 2 개의 플라즈마 처리 구역들로부터의 프로세스 가스의 성분들뿐만 아니라, 아직 변환되지 않은 성분들이 혼합되고, 따라서 플라즈마 처리 구역들 내로 공급되는 프로세스 가스의 균질화가 달성된다.  이것은 상이한 플라즈마 처리 구역들 내의 플라즈마 프로세스의 차이들로부터 생기는 개별 기판들 간의 플라즈마 처리의 불균질성을 감소시킨다.
Patent KR-20160145210-A (KR)
Inventor: MATSUKI YASUHIRO
IPC: C21D8/02
Filed: 2012-04-09
Abstract: 관 길이 방향의 재질 편차가 ΔTS : 20 ㎫ 미만으로 적고, 항복비 : 80 ％ 이하의 저항복비와, 항복 강도 (YS) : 379 ∼ 552 ㎫, 인장 강도 (TS) : 655 ㎫ 이상의 고강도를 갖는 저항복비 고강도 전봉 강관 및 그 제조 방법을 제공한다.     구체적으로는, 질량％ 로, C : 0.38 ∼ 0.45 ％, Si : 0.1 ∼ 0.3 ％, Mn : 1.0 ∼ 1.8 ％, P : 0.03 ％ 이하, S : 0.03 ％ 이하, sol.Al : 0.01 ∼ 0.07 ％, N : 0.01 ％ 이하를 함유하는 조성을 갖는 강 소재에, 마무리 압연 개시 온도를 950 ℃ 이하, 마무리 압연 종료 온도가 820 ∼ 920 ℃ 의 범위의 온도가 되는 마무리 압연을 실시하여 열연 강대로 하고, 그 열연 강대를, 마무리 압연 종료 후, 권취 온도를 650 ∼ 800 ℃ 의 범위의 온도로 하여 코일상으로 권취한다.     코일상으로 권취된 열연 강대를 공급하여, 성형, 전봉 용접으로 이루어지는 조관 공정을 가열하지 않고 실온에서 실시하여 전봉 강관으로 한다.
Patent KR-20170008782-A (KR)
Title: 변성 페놀 수지와, 상기 수지의 제조 방법 및 상기 수지를 강화 수지로서 사용하는 방법
Inventor: BANACH TIMOTHY E
IPC: C08G8/22
Filed: 2015-05-12
Abstract: 본 발명은 노볼락 수지의 제조 방법 및 노볼락 수지를 강화 수지로서 사용하는 방법에 관한 것이다. 한 방법은, 염기의 존재 하에 1종 이상의 알킬페놀과 알데하이드를 반응시켜 레졸 수지를 형성하는 단계로서, 알킬페놀 1몰에 대하여 1.5몰 이상의 알데하이드를 반응시키는 단계; 및 산 촉매의 존재 하에 레졸 수지와 1종 이상의 페놀 화합물을 반응시켜 노볼락 수지를 형성하는 단계로서, 알킬페놀 1몰에 대하여 1.5몰 이상의 페놀 화합물을 반응시키는 단계를 포함한다. 또 다른 방법은, 염기의 존재 하에 1종 이상의 알킬페놀과 알데하이드를 반응시켜 레졸 수지를 형성하는 단계; 및 고온에서 레졸 수지와 1종 이상의 페놀 화합물을 반응시켜 노볼락 수지를 형성하는 단계를 포함한다.
Patent KR-20170021263-A (KR)
Title: 인터로킹 부착부를 갖는 수술용 프로브
Inventor: ARTSYUKHOVICH ALEX
IPC: B23K103/08
Filed: 2015-05-12
Abstract: 안과 처치에 사용하기 위한 광학 프로브를 제조하는 방법은, 캐뉼러의 근위 부분 내에 페룰을 위치시키는 단계로서, 광 파이버는 캐눌러의 원위 부분 내에 배치된 광학 요소를 향해 페룰을 통해 적어도 부분적으로 연장되는, 단계; 및 캐뉼러에 레이저 에너지를 인가함으로써 페룰에 캐뉼러를 결합하는 단계를 포함할 수 있다. 근위 부분 및 원위 부분을 포함하는 캐뉼러; 캐뉼러의 근위 부분 내에 배치된 페룰로서, 캐뉼러 및 페룰은 캐뉼러 및 페룰 내의 맞물림 변형부에 의해 함께 결합되며; 광학 파이버는 광학 프로브 내에 적어도 부분적으로 위치되며, 상기 광학 파이버는 광원으로부터 광을 수용하고 캐뉼러의 원위 부분 내에 위치된 광학 요소로 광을 안내하도록 구성되는 것을 포함하는 광학 프로브가 제공될 수 있다.
Patent KR-20180080431-A (KR)
Inventor: LEE SANG JUN
IPC: H01L21/67
Filed: 2017-01-04
Abstract: An objective of the present invention is to provide a substrate processing apparatus and a substrate processing method, capable of preventing a process accident from occurring by detecting a fluid falling from a nozzle. To achieve the above objective, the substrate processing apparatus of the present invention includes: a chamber accommodated therein with a substrate to perform a cleaning process; a spin chuck rotatably installed in the chamber to support the substrate; a nozzle for supplying a fluid onto the substrate; a recovery chamber surrounding the substrate while being spaced apart from the spin chuck by a predetermined interval to collect the fluid scattered on the substrate; and a fluid detection unit for detecting the fluid falling from the nozzle.
Patent KR-20170013370-A (KR)
Inventor: KIM JAE HYUNG
IPC: G06Q20/38
Filed: 2017-01-23
Abstract: According to a method for providing a payment service of the present invention, in a method performed by a server capable of communicating with a payment requesting terminal and capable of communicating with a customer wireless terminal: some pieces of information necessary for payment are received from a payment requesting terminal, and some pieces of information necessary for payment are received from a customer wireless terminal connected to a wireless communication channel; at least one piece of information among the information received from each of the payment requesting terminal and the customer wireless terminal is compared so as to match the information received from the payment requesting terminal and the information received from the customer wireless terminal; when the information received from the payment requesting terminal and the information received from the customer wireless terminal are matched, a portion of value partly excluded from the at least one piece of information received from the payment requesting terminal, and the remaining portion of value included in the at least one piece of information received from the customer wireless terminal are combined to constitute at least one piece of information necessary for payment, and the constituted information is compared with information pre-registered in a designated DB so as to verify the validity of the constituted information; and, when the validity of the constituted information is verified, the information received from the payment requesting terminal and the information received from the customer wireless terminal are combined to provide a payment service requested from the payment requesting terminal. According to the present invention, there is an advantage that a card payment can be easily provided, when required, during a telephone conversation by providing a payment settlement service by using channel switching.
Patent KR-20180031545-A (KR)
Inventor: KOO YEON JIN
IPC: E04B5/38
Filed: 2017-02-02
Abstract: In the present invention, a fastening tool (press bolt) for combining process invented by an inventor of the present invention is applied to be automatically combined to an upper portion deck plate without unnecessarily forming a perforation hole (112) matched to the location of a fastening portion on the deck plate and having a sealed state such that leakage of concrete liquid placed into the fastening portion can be perfectly prevented, thereby perfectly preventing flowing down of concrete liquid placed later on.
Patent KR-20170026414-A (KR)
Inventor: JEON DAE YEON
IPC: G08G1/07
Filed: 2017-02-17
Abstract: The present invention relates to a method for operating an autonomous vehicle according to road conditions. While driving in a lane, the autonomous vehicle changes lanes, or turns left or right, or makes a U-turn, or reverses depending on road information.
Patent KR-20170103670-A (KR)
Title: Radiation-sensitive resin composition, process for forming resist pattern, radiation-sensitive acid generator, and compound
Inventor: NAMAI HAYATO
IPC: G03F7/038
Filed: 2017-03-02
Abstract: The purpose of the present invention is to provide a radiation-sensitive resin composition having excellent line width roughness (LWR) performance and the like, and a method for forming resist patterns. The radiation-sensitive resin composition of the present invention contains a polymer having a first structure unit including an acid dissociable group, a compound represented by the following formula (1), and a solvent. In formula (1), R^1 and R^2 are a hydrogen atom or a C_1-C_20 monovalent organic group which does not include a fluorine atom. R^3, R^4, R^5, R^6 and R^7 are a hydrogen atom, a fluorine atom, or a C_1-C_20 monovalent organic group. However, at least one of R^1, R^2, R^3 and R^4 indicates a group represented by OR^Q. R^Q is a hydrogen atom or a C_1 to C_20 monovalent organic group. R^1 and R^2, R^1 and R^3, R^1 and R^5, R^3 and R^4, R^3 and R^5, or R^5 and R^6 are added to each other to form a ring structure of 3 to 20 of the number of ring-forming atoms along with carbon atoms to which they are bonded. Y^- is SO_3^- or COO^-. X^+ is a monovalent radiation-sensitive onium cation.
Patent KR-20180101047-A (KR)
Inventor: HA YU SOL
IPC: G06F3/01
Filed: 2017-03-03
Abstract: According to the present invention, an electronic device capable of preventing the cause of motion sickness of a user comprises: a main body formed to be in contact with a part of a body of a user; a display unit installed in the main body, and playing virtual reality content; a sensing unit sensing a movement of the main body while playing the virtual reality content; and a control unit determining movement information of the main body at a time when a playback of the virtual reality content is stopped, and controlling the display unit to display a guide image representing the movement information of the main body on the virtual reality content.
Patent KR-20180101829-A (KR)
Inventor: JUNG YEON CHANG
IPC: B05B9/08
Filed: 2017-03-06
Abstract: The present invention relates to an agricultural pesticide sprayer container capable of spraying an agricultural pesticide selectively in a left or right direction while flexibly changing various directions including spraying to the front or lateral sides. To achieve the purpose, a pesticide storage part is placed in the upper part to store pesticide and a pesticide supply pump is placed in the lower part, and a pesticide spray part, including a front hose supply slit part formed on the front side to supply a supply hose and a lateral hose supply slit part formed on both sides, is separated and combined. The front hose supply slit part is formed as a slit groove having a set horizontal size to enable the supply hose to change a spraying direction to the left or right side from the center. The lateral hose supply slit part is formed as a slit groove elongated horizontally on the right and left sides of the pesticide spray part to enable the supply hose to be used in the lateral hose supply slit part selectively or simultaneously.
Patent KR-20180103364-A (KR)
Inventor: PARK YONG DAE
IPC: A61K49/00
Filed: 2017-03-09
Abstract: The present invention relates to a squaraine derivative and a composition for near-infrared or photoacoustic imaging for tumor diagnosis comprising the same. The squaraine derivative according to the present invention can be detected through near-infrared imaging or photoacoustic imaging, and a photoacoustic signal is remarkably enhanced as compared with a known squaraine dye. Therefore, when introducing and using a target ligand such as RGD, the composition may be useful as a near-infrared imaging or photoacoustic imaging composition for diagnosis.
Patent KR-20180105309-A (KR)
Title: Multifunctional gas shutoff device
Inventor: KIM JONG ILL
IPC: F17D5/00
Filed: 2017-03-15
Abstract: The present invention relates to a multifunctional gas shut-off device and, more specifically, to a multifunctional gas shut-off device to automatically shutoff gas supply and send a warning message to a set portable terminal when gas leakage or earthquake is detected. According to one embodiment of the present invention, the multifunctional gas shut-off device to control a shut-off valve for controlling a gas flow inside a gas pipe comprises: a valve determination unit to mechanically operate the shut-off valve; a manual operation unit to manually operate the valve determination unit; a control unit to control the valve determination unit; a timer setting unit to set time and transfer the set time to the control unit; a signal output unit including an alarm unit receiving a signal of the control unit to inform a user of the signal as a speech in order to make the user recognize the signal, a display unit to display the signal on a screen, and a transmission unit to transmit a text message to the set portable terminal; a gas sensor unit to detect leakage of gas; and an earthquake sensor unit to detect earthquake. The multifunctional gas shut-off device is mounted on a gas pipe in which the shut-off valve is placed, and the control unit controls the valve determination unit in accordance with a signal transmitted from at least one of the timing setting unit, the gas sensor unit, and the earthquake sensor unit to shut off the gas flow.
Patent KR-20180106381-A (KR)
Inventor: LEE YOUNG HOON
IPC: H01M10/04
Filed: 2017-03-20
Abstract: The present invention relates to an electrode assembly having a structure in which a plurality of unit cells are wound by a sheet-like folding separator. More specifically, the present invention relates to an electrode assembly. Each of unit cells is bonded to each other by heat fusion while a lamination separator is interposed between a positive electrode and a negative electrode. A folding separator shows higher mechanical properties and thermal properties as compared with the lamination separator.
Patent KR-20180107953-A (KR)
Inventor: SON KI SUK
IPC: H04L12/28
Filed: 2017-03-23
Abstract: A multi-purpose communication system for an electric vehicle is disclosed. The communication system includes a WiFi module, an LPWA module, an AVB Ethernet module, and a PLC module. A conversion controller performs a switching operation to change a communication path for a radio station or a station according to a connection state with the station and a communication state for the radio station. Data communication with an external server or another vehicle is possible using a wireless communication network. Also, various setting data can be transmitted and received in a state in which the vehicle is received in the station using PLC communication. A system capable of performing the above functions is modularized into one, thereby being easily mounted on the vehicle. Also, a stable communication environment can be provided by performing good communication by automatic switching or multiple communication according to a quality factor of the communication network.
Patent KR-20180110435-A (KR)
Title: Transplanting apparatus
Inventor: CHONG WOO SUK
IPC: A01G23/04
Filed: 2017-03-29
Abstract: A tree digging apparatus according to the present invention comprises: a first blade and a second blade for cutting the roots of a tree with surrounding soil and supporting lower ends of the cut roots; and a driving unit controlling operations of the first blade and the second blade, wherein both ends of the first blade and the second blade are aligned on the same rotation axis and rotate around the rotation axis. According to the tree digging apparatus of the present invention, not only the cutting of the tree roots and the cutting of the trees can be facilitated, but also the mobility and supportability of the tree digging apparatus can be improved.
Patent KR-20170113448-A (KR)
Inventor: JEONG KWANG SEOB
IPC: H01L31/042
Filed: 2017-03-31
Abstract: 본 발명은 비화학량론적 양자점의 밴드 내 전자전이를 이용한 적외선 장치에 관한 것으로, 보다 구체적으로는, 양자점 코어 및 상기 코어에 결합된 무티올 리간드를 포함하고 밴드 내 불연속적 에너지 준위 사이의 전자전이로부터 적외선을 방출하는, 비화학량론적 양자점 나노입자 및 상기 나노입자를 포함하는, 적외선 장치에 관한 것이다. 본 발명에 따른 적외선 장치는 금속의 비율이 칼코겐의 비율보다 높은 양자점의 밴드 내 불연속적 에너지 준위 사이의 전자전이를 이용함으로써, 적외선, 특히 중적외선 또는 원적외선을 방출하는 효과가 있다. 또한 상기 양자점은 무티올 리간드를 포함하여 제조됨으로써, 종래 티올 리간드에 비해 양자점의 n 타입 도핑을 유지하면서 동시에 리간드 치환이 매우 용이한 효과가 있다. 비화학량론적 양자점에 양 또는 음의 전압을 인가함으로써, 양자점에 입사되는 빛의 투과율을 가역적으로 조절하는 효과가 있다.
Patent KR-20180114276-A (KR)
Inventor: LEE SUN HYUNG
IPC: H01M4/66
Filed: 2017-04-07
Abstract: The present invention relates to a cathode for a secondary battery comprising: an electrolytic copper foil current collector; a cathode active material layer provided on one or both surfaces of the electrolytic copper foil current collector and including lithium powder; and a protective layer provided on the cathode active material layer, and to a method for manufacturing the same and a lithium secondary battery using the same. The thickness of the electrolytic copper foil current collector is 2-20 μm, and the thickness of the cathode active material layer and the protective layer on the electrolytic copper foil current collector is 100 μm or less.
Patent KR-20180115960-A (KR)
Inventor: OH HEE BOO
IPC: E04H9/02
Filed: 2017-04-14
Abstract: The present invention relates to a method for constructing a seismic ALC house. Even when a house is constructed with an autoclaved lightweight concrete (ALC) which has a 7 times lower compression strength relative to general concrete, a structure in which an ALC wall body and a slab are seemed to be integrally connected is realized to perform a seismic function through a concrete base, a longitudinal reinforcement (main reinforcement) for an ALC wall, steel for reinforcing edges, and steel for an ALC slab. The method for constructing a seismic ALC house comprises: a step of forming a concrete base; a step of forming an ALC base end layer; a step of adjusting a horizontality of the ALC base end layer with respect to the concrete base; a step of driving a strong anchor on the concrete base; a step of fastening and fixing a male screw sealing vertical reinforcement to the strong anchor; a step of bonding the concrete base with the ALC base end layer; a step of forming a first ALC block masonry layer; a step of charging mortar in a groove; a step of putting ALC panels in each gap between cross steels for slabs; and a step of fastening and connecting the cross steels for slabs with a transverse reinforcement.
Patent KR-20180117277-A (KR)
Inventor: RHIM SUNG HAN
IPC: B60R13/04
Filed: 2017-04-19
Abstract: The present invention relates to a vehicle door protector and, more specifically, relates to a vehicle door protector which is in contact with an outside barrier and another vehicle when a door is opened to prevent damage to a subject vehicle, the other vehicle, and the outside barrier, and comprises: a pneumatic generation unit (100) operating to generate pneumatic pressure when a door (10) is opened; a second cylinder (200) operating by receiving the pneumatic pressure from the pneumatic generation unit; a working rod unit (300) mounted in an end of the second cylinder to slide in left and right directions; and a protector (400) installed in an end of the working rod unit to enter from the door in accordance with left and right movement of the working rod unit, and slidingly inclined when being drawn out of the door to surround an edge (11) of the door.
Patent KR-20180119750-A (KR)
Inventor: CHOI YOUNG HEE
IPC: G06T7/11
Filed: 2017-04-26
Abstract: The present invention relates to a method for detecting parking obstacles using an optical flow, comprising: a first step of extracting particular point data from an image inputted through a camera; a second step of selecting obstacle recognition data from the extracted particular point data; and a third step of determining obstacle movement among the selected obstacle recognition data, wherein the first step includes a step of selecting a region of interest (ROI) and a step of extracting a FAST particular point. In a prior art, the obstacle image is difficult to be extracted from the ROI of the image filmed when parking a vehicle. In order to solve the difficulty of the prior art, the particular point is used to detect the parking obstacle and movement of the parking obstacle can be estimated by checking the optical flow.
Patent KR-20180122255-A (KR)
Inventor: MYUNG SE HO
IPC: H04L1/00
Filed: 2017-05-02
Abstract: The present disclosure relates to a 5G or pre-5G communication system for supporting a higher data transmission rate than a 4G communication system like LTE. A method for channel encoding in a communication or broadcasting system includes the steps of: determining one or more of a quasi-cyclic shift and a cyclic shift; generating a codeword; performing inner channel encoding; performing the quasi-cyclic shift on the codeword; and performing the cyclic shift on the quasi-cyclic shifted codeword. Accordingly, the present invention can transmit data through a shift operation of the codeword.
Patent KR-20180126654-A (KR)
Title: Method for Automatic Setting Image Locating Layout of Photo Book
Inventor: KIM JAE HYUNG
IPC: G06F3/0481
Filed: 2017-05-17
Abstract: The present invention relates to an automatic photograph book image arrangement layout setting method. According to an embodiment of the present invention, the automatic photograph book image arrangement layout setting method is executed through a program installed on a wireless terminal including a touchscreen. The automatic photograph book image arrangement layout setting method includes: a first step of executing the program including a printing photograph book editing function and storing template layout information; a second step of determining the printing template arrangement; a third step of checking the photograph images determined to be arranged in one template area; a fourth step of checking the template layout information; and a fifth step of arranging the photograph images in arrangement areas corresponding to the template layout information in a matching manner.
Patent KR-20170131277-A (KR)
Inventor: ROBERTS RICHARD
IPC: B29C70/48
Filed: 2017-05-19
Abstract: The present invention relates to a manufacturing of composite structures, and more particular, to a method and a system for injecting resins into a composite preform. The method comprises the steps of: placing a composite preform (10) on an upper tool surface (111) of a tool (110); placing a resin storage element (120) on the tool surface (111) in a lower side of the composite preform (10); arranging a vacuum packaging film (130) on the tool surface (111) to cover the composite preform (10) and the resin storage element (120); providing a resin supplying unit (141); providing a resin flux path (142) from the resin supplying unit (141), to a resin injecting chamber (140) in an upper side of the composite preform (10), to a resin storage place (121) via the composite preform (10) and via a storage inlet (123); and pushing resins through the resin flux path (142) from the resin supplying unit (141) to inject resins to the composite preform (10), and applying partially at least vacuum pressure to a storage outlet (122) to set a pressure difference between the resin supplying unit (141) and the storage outlet (122) to gather excessive resins in the resin storage place (121).
Patent KR-20180128214-A (KR)
Inventor: KWON JOONK HYUK
IPC: C12M1/33
Filed: 2017-05-23
Abstract: The present invention relates to a cell crushing method for crushing a large amount of cell bodies by a mechanical method, and more specifically, to a cell crushing method for crushing a large amount of cell bodies by granulating minerals and inserting the same as a crushing aid. According to an embodiment of the present invention, the cell crushing method using the mineral crushing aid comprises: a preparation step of granulating natural minerals; a precipitation step of precipitating a cell liquid including cell bodies to be crushed; a first separation step of separating the cell bodies precipitated in the cell liquid; a coagulation step of coagulating the cell bodies by inserting natural minerals into the cell liquid primarily separated in the first separation step; a second separation step of separating the cell bodies coagulated in the coagulation step; a crushing step of operating a bead mill by inserting the cell liquid secondarily separated in the second separation step into the bead mill; and a completion step of discharging the cell liquid including the cell bodies crushed in the bead mill.
Patent KR-20180128689-A (KR)
Title: Compound and organic solar cell comprising the same
Inventor: LIM BO GYU
IPC: H01L51/42
Filed: 2017-05-24
Abstract: The present specification is to provide a compound which can be used as a material for an organic layer of an organic solar cell, and to an organic solar cell including the same. The compound comprises a unit represented by chemical formula 1. In chemical formula 1, R1 to R3 are the same or different from each other and are independently an alkyl group, a is an integer of 1 to 5, and Ar2s are the same or different when a is 2 or more.