baber/WOPTO huggingface dataset:
Patent KR-20010046256-A (KR)
Inventor: HWANG AE MIN
IPC: C12N1/20
Filed: 1999-11-11
Abstract: PURPOSE: Provided is Pseudomonas putida HPLJS-1 (KCTC 0666BP) producing biosurfactant which is useful in effectively eliminating oil in soil and cleansing a tank tainted with oil. CONSTITUTION: Pseudomonas putida HPLJS-1 (KCTC 0666BP) is obtained by the next steps of: i) collecting soil tainted with oil and diluting it with NaCl 0.85 and streaking the solution onto two minimum salt media, one has soybean oil as carbon source and the other has oil; ii) cultivating the media at 30 deg.C to obtain about 100 strains; iii) cultivating the strains in nutrient broth having glucose, hexadecane, and olive oil in a ratio of 1:1:1; iv) selecting the strain which generates biosurfactant; v) streaking the strain in nutrient broth and cultivating the strain at 30 deg.C; and vi) keeping colonies at 4 deg.C and subculturing the colonies every two weeks. And Pseudomonas putida HPLJS-1 (KCTC 0666BP) is gram negative, rod, aerobic etc. Biosurfactant, rhamnose, is produced by culturing Pseudomonas putida HPLJS-1 (KCTC 0666BP) in an optimum medium at 30 deg.C, 15 rpm, for 5 days, wherein the optimum medium includes K2HPO4 1.5g/l, NaH2PO4 0.2g/l, MgSO4·7H2O 0.5g/l, NaCl 0.5g/l, MnSO4·5H2O 0.5g/l, CaCl2·2H2O 0.05g/l, yeast extract 2.0g/l, and a mixture 5 of glucose and olive oil in a mixing ratio of 1:1.
Patent KR-20000007021-A (KR)
Title: Water saving scrubbing fabric device
Inventor: PARK JIN SU
IPC: A47L17/08
Filed: 1999-11-19
Abstract: PURPOSE: A water saving scrubbing fabric device is provided to improve the washing efficiency by controlling the washing water supply spent for dish washing and by directly supplying the washing water to the contacting face of the sponge and the face to be washed. CONSTITUTION: The device is formed by:a flexible water supply pipe(6); a connection device(5); a tube(3); and a valve device(9).; Herein, the devices weakens the gripping strength and supply small amount of washing water when washing by using washing agent.; Herein, the washing comprises the steps of:jetting the washing agent on the wet sponge(2) and the scrubber(1); gripping the valve device tightly when rinsing; and directly supplying much washing water onto the face to be washed through the sponge and the scrubber.; Thereby, the washing time and washing water are reduced by integrating the washing by using the washing agent and the rinsing.
Patent KR-20000052381-A (KR)
Inventor: HARASHIKE MASAHIRO
IPC: B26D1/00
Filed: 1999-11-26
Abstract: PURPOSE: An apparatus for forming slits is provided to stably form slits on a sheet since a cutter roll is not slipped even regardless of abrasion of cutting edges of a plurality of slit forming blades or an abrasion frequency of a receiving roll. CONSTITUTION: An apparatus(1) for forming slits on a sheet includes a cutter roll(2) disposed with a plurality of slit forming blades(4) on a periphery, and a receiving roll(3) disposed in contact with the cutter roll for rotating the cutter roll, wherein the sheet is supplied between the cutter roll and the receiving roll to be formed with slits, and the plurality of slit forming blades respectively has a plane edge part aligned between the blades, so that the blades are positioned at a same height with relation to a rotation center of the cutter roll and the receiving roll is prevented from being scratched by the cutting blades.
Patent KR-20010054186-A (KR)
Inventor: PARK SE HUN
IPC: H02K5/24
Filed: 1999-12-03
Abstract: PURPOSE: An electric motor is provided to be capable of being mounted on an equipment set for saving manufacturing costs and being commonly used by utilizing a separate supporting member. CONSTITUTION: The electric motor comprises a housing(10) for housing a stator and a rotor, and a rotating shaft(25) outwardly extended from the housing. A supporting member(30) is mounted on an outer wall of the housing(10). A damping member(41) is coupled to the supporting member(30) to be contacted with a predetermined motor mounting part. Preferably, the supporting member(30) is coaxial with the rotating shaft(25) and the damping member(41) has a ring shape to surround the supporting member(30). A bearing mount(15) for mounting a bearing is formed on the supporting member(30).
Patent KR-20010055020-A (KR)
Inventor: PARK MIN HA
IPC: B60R11/02
Filed: 1999-12-09
Abstract: PURPOSE: A preventing method for the antenna of a vehicle is provided to prevent the damage of the antenna by stopping the antenna operating in case of the existence of an obstruction on the pulling course of the antenna. CONSTITUTION: To prevent an antenna from being damaged, a system turns on a radio and operates a sensor for sensing if an obstruction exists on the drawing course of the antenna. Then, an ECU(electric control unit) decides if the obstruction exists on the pulling course with a signal from the sensor. If not, the ECU pulls the antenna. With the obstruction, the antenna is not pulled and a driver moves a vehicle to the other place to normally pull the antenna. After that, the system operates the sensor again.
Patent KR-20010055476-A (KR)
Inventor: KANG TAE UK
IPC: B22D11/06
Filed: 1999-12-10
Abstract: PURPOSE: An apparatus for discharging fume of a twin roll strip casting machine is provided to prevent cracks of the surface of a strip and obtain even severity of quench in a roll width direction by discharging fume to the outside so that a contaminated mixed gas, fume, which is formed on the upper part of molten metal pool is not adsorbed on the surface of the twin rolls. CONSTITUTION: In a twin roll strip casting machine consisting of twin rolls (3,3a) each of which rotate in an opposite direction; edge weirs (4) installed at both ends of the twin rolls (3,3a) so as to form a molten metal pool (5); a molten metal surface cover (7) installed so as to form an environmental gas space on the upper part of the molten metal pool (5); first and second gas supplying holes (8,9) installed in the molten metal surface cover (7) for supplying non-oxidized gases to the sides of the twin rolls (3,3a) and the molten metal surface; and shielding curtains (11) installed at the molten metal surface cover (7) corresponding to the twin rolls (3,3a) so as to seal the environmental gas space, wherein a strip (20) is casted by passing molten steel through between the twin rolls (3,3a), the apparatus for discharging fume of a twin roll strip casting machine comprises a plurality of discharging holes (10) mounted on the molten metal surface cover (7) in a width direction of the rolls so that fume moving to the center part of the molten metal pool (5) can be discharged to the outside by the ejecting force of the non-oxidized gases which is ejected from the first and second gas supplying holes (8,9).
Patent KR-20010056004-A (KR)
Inventor: LEE JONG BEOM
IPC: D04B1/16
Filed: 1999-12-14
Abstract: PURPOSE: A process for preparing a pile knitted fabric by knitting ground yarns and pile yarns using a kind of polyester at two places on a flat knitting machine is provided, which improves quality of a product as well as promoting productivity by remarkably reducing manufacturing processes. CONSTITUTION: In a process for the manufacture of a pile knitted fabric formed by ground yarns(1) and pile yarns(2), this process comprises the steps of: cross-linking ground yarns of 150 to 180D/92 to 120F and pile yarns of 150 to 750D/1-5 strands/92 to 120F at two places on a flat knitting machine, knitting to have a cross shape of U type and a pile density of 7 to 12 strands/in respectively in both width and length and dyeing.
Patent KR-20000048123-A (KR)
Inventor: TAMAKI SATOSHI
IPC: G11C11/401
Filed: 1999-12-14
Abstract: PURPOSE: A program flip-flop is provided to compact a circuit scale of an existing memory device having a redundant circuit by removing a one-shot pulse generator. CONSTITUTION: In cutting a fuse(Fa), a p-channel transistor(p1) is turned on with a low gate potential by increasing a resistance of fuse than a resistance of load resistor(Fb). A potential of point 'A' is raised to a high level to turn off a p-channel transistor(p2). A point 'B' is combined in a ground line and to be a low level. The low level maintains the p-channel transistor(p1) in an on state. A program flip-flop transfers the high level through the point 'A' as a resulted signal. Without cutting the fuse(Fa), the p-channel transistor(p2) is turned on by increasing the resistance of fuse than the resistance of load resistor. The potential of point 'A' is reduced to a ground level by turning off the p-channel transistor(p1). The program flip-flop transfers the resulted signal of low level through the point 'A'. Result signals of high level and low level correspond each to the non-cut status and the cut status of the fuse. Thereby, a redundant circuit having the program flip-flop does not need a one-shot pulse generator and a circuit scale of the redundant circuit is reduced.
Patent KR-20010056155-A (KR)
Title: Method for operating memory of raid controller
Inventor: JU SEOK MAN
IPC: G06F12/00
Filed: 1999-12-14
Abstract: PURPOSE: A method for operating a memory of a RAID controller is provided to enhance storing devices and a control period processing velocity by operating a memory installed in a controller for controlling a plurality of the storing devices being connected to a RAID system as a cache memory operating method. CONSTITUTION: If a RAID controller waits a transmission of a command from a host system and receives a data processing related command of a storing device from the host system(S401), the kind of the command is perceived(S402). If the kind is reading, the host system searches whether wanted data exist in a memory(S410). If the corresponding data are stored in the memory(S411), the data of the corresponding cache line are transmitted to the host system(S412). If the data wanted in the host system does not exist in the memory, writing cache area, that is, a line having largest value of a frequency number display area(LRU) out of an invalid status or an exclusive line is selected by searching a tag area by lines of the memory and frequency number display area(LRU)(S413). The data wanted in the host system are searched in a hard disk and the data are stored(S414) in data area of the line selected in the above (S413) stage, and the tag area of the line is converted into the exclusive status(S415), and the data of the corresponding cache line are transmitted to the host system(S416).
Patent KR-20010065678-A (KR)
Inventor: KIM DONG YEOL
IPC: H01L21/66
Filed: 1999-12-30
Abstract: PURPOSE: An apparatus for connecting a bit mapper with a probe station is provided to check many kinds of semiconductor devices by using only one dut board. CONSTITUTION: An upper loading face(16) of a bit mapper(10) is formed on an upper face of a main body(12) with a rectangular shape. An opening portion is formed on a center portion of the bit mapper(10). A probe station(20) is loaded on the upper loading face(16) of the bit mapper(10). A support portion(22) is formed at the probe station(20). An interface board(67) is connected with the support portion(22) of the probe station(20). A test member(60) having a test lens(65) is fixed to the interface board(67). A dut board(30) is installed at a center portion of the interface board(67). A probe card(50) is contacted with a pogo ring(35). The probe card(50) is connected with a multitude of pogo pin(45).
Patent KR-20010065731-A (KR)
Inventor: CHOI JAE MAN
IPC: H04N5/74
Filed: 1999-12-30
Abstract: PURPOSE: A light modulation device of image projection system is provided to secure maximum light quantity of a mono color light reflected several times and perform a complete blackbody with minimum light quantity by controlling interval between a blackbody and a mirror which are settled contrary and opposite to each other according to a brightness signal about each induced incident mono color light. CONSTITUTION: A plurality of mirror(52a, 52b) and a plurality of blackbody(53) are settled alternately on surface of two plates which are settled contrary and opposite to each other in an appointed angle to a light path of an induced mono color light. A driving member(54, 56) is settled on the back of the plurality of mirror(52a, 52b) and blackbody(53) and controls interval between the plurality of mirror(52a, 52b) and blackbody(53). A driving circuit unit controls driving of the driving member(54, 56) in correspondence to an image signal.
Patent KR-20010059884-A (KR)
Title: Apparatus for sensing air pressure of tire
Inventor: HAN SANG IL
IPC: B60C23/00
Filed: 1999-12-30
Abstract: PURPOSE: A tire air pressure sensing apparatus is provided to enable a driver to take necessary measures by accurately notifying degree of pneumatic loss to the driver. CONSTITUTION: A tire air pressure sensing apparatus includes a pressure sensor(26) sensing air pressure of a tire(20), a piezoelectric element(30) generating voltage if the tire receives regular pressure, a transponder(28) converting the pressure value sensed at the pressure sensor into pneumatic data for transmitting when the voltage is generated, an antenna coil(34) transmitting data received from the transponder, and a control element judging pneumatic loss by comparing the transmitted tire air pressure with the preliminarily set reference value and outputting a control signal for controlling off-time of an alarm lamp and an alarm according to the pneumatic loss.
Patent KR-20000049064-A (KR)
Title: Hiv and cancer treatment
Inventor: CAMDEN JAMES BERGER
IPC: A61P35/00
Filed: 1997-11-26
Abstract: PURPOSE: Provided is a method of inhibiting the growth of viruses, particularly HIV, cancers and tumors in human and warm blooded animals, involving the administration of herbicidal and fungicidal agents. Tumor size is decreased. The growth of the cancer is slowed, and the replication of viruses is inhibited. The treatment is particularly effective when the virus or cancer is the result of a mutated cell, i.e. an animal cell which has been mutated by incorporating therein genetic material from plants, fungi or molds. CONSTITUTION: A method of treating HIV or other viral infections by administering a herbicide or fungicide or derivative thereof to an animal or human is provided. The fungicides or herbicides can be used in conjunction with other treatments, e.g. with AZT or protease inhibitors for the treatment of HIV. For example, thiabendazole and chloropropham have been shown to quickly reduce the level of virus production from cell populations chronically infected with HIV-1 and the antiviral effect is maintained with continued compound exposure. This reduction of virus production occurs at concentrations which are non toxic to the host cell and which have no effect on the syntheses of cellular DNA, RNA and protein. Further, chronically infected cells treated for prolonged periods of time with thiabendazole and chloropropham were not super-infected with HIV. A method for inhibiting the growth of tumors and cancers in mammals comprising administering a herbicidal or fungicidal derivative is also provided. The fungicides or herbicides can be used in conjunction with other treatments, e.g. taxol for the treatment of breast cancer. Potentiators can also be included in the herbicidal or fungicidal composition. This method is particularly effective when the cancer or virus is an animal cell genetically modified by plant or fungus genetic material. A chemotherapeutic agent can also be administered first to significantly reduce the size of the cancer and then the treatment with the herbicide or fungicide is used. These methods are particularly effective when the cancer or virus is a mutated cell comprising plant or fungal genetic material.
Patent KR-20000057625-A (KR)
Title: Fault-resilient automobile control system
Inventor: WILLIAM WONG
IPC: B60W50/029
Filed: 1997-12-10
Abstract: PURPOSE: A fault-resilient automobile control system is provided to tolerate fault about component failure by integrate diverse and separate automobile components. CONSTITUTION: An automobile control system includes a master control unit (MCU) electrically coupled via a primary data communications bus to the electronic automobile components. The MCU is master of the bus and manages data flow over the bus among the electronic automobile components. The MCU can be configured with a routing table to route data monitored in one component to one or more other components. The MCU is also capable of performing the same functions as those performed by local controllers at the eletronic components. During initialization, driver software for all of the local controllers is downloaded and stored at the MCU. In the event that a local controller fails, the MCU executes the driver software for the failed controller to remotely control the electronic automobile component in place of the failed local controller. Switching logic is installed at each of the electronic components to selectively route data to the primary bus, circumventing the failed controller. The automobile control system has a secondary control unit (SCU) electrically coupled to the MCCI via the primary bus. The SCU is a standalone computer that supports clients and other devices on a secondary support bus. The SCU is also configured to backup the MCU. During normal operation, the SCU is subordinate to and controlled by the MCU on the primary bus. In the event that the MCU fails, however, the SCU assumes control of the data communications network and manages the data flow among the electronic automobile components.
Patent KR-20000069534-A (KR)
Title: Absorbent structure having decoupled topsheet
IPC: A61F13/15
Filed: 1997-12-05
Abstract: Absorbent structures comprising a topsheet, a backsheet with an absorbent core between the topsheet and the backsheet are described. The absorbent structures further comprise a support strip that provides a contractive force that causes at least a portion of the support strip and at least a portion of the topsheet to become decoupled from the absorbent core. Alternative embodiments of the absorbent structure include laterally extending flaps and an abbreviated undergarment.
Patent KR-20000069847-A (KR)
Title: 라디오 전치 회로
IPC: H04B1/16
Filed: 1998-01-07
Abstract: 적어도 2개의 증폭기 믹서 캐스케이드를 포함하는 라디오 전치 회로에 있어서, 증폭기(1, 2)는 믹서(4, 5)를 통해 스위치 온 또는 오프된다. 증폭기 믹서 캐스케이드 사이의 스위칭에 의해, 전력 소비가 저하된다.
Patent KR-20000070320-A (KR)
Title: 화면작성에디터
IPC: G06F9/44
Filed: 1998-11-19
Abstract: 본 발명에 의한 화면작성에디터(31)에는 터치스위치(touch switch)(9)등 입력장치에서의 조작에 의해 표시화면을 전환시킬수 있는 표시장치(2)로 화면을 편집할 수 있고 표시제어를 할수 있다. 
     더 구체적으로 말하면, 화면작성자의 조작에 의해 화면천이편집부(screen shift editing unit)(32)가 화면천이차트도(screen shift chart)를 작성하며, 또 이 화면천이차트도에 의해 화면을 천이시키는 화면전환정보를 작성하여 각 화면상에 전환화면(다음에 표시할 수 있는 화면)을 선택하는 터치스위치로 표시화면에 자동적으로 설정한다. 
     또, 화면천이편집부(32)에서는 이전에 작성한 화면정보데이터를 이용하여 자동적으로 화면천이 챠트도를 작성한다. 
     더 나아가서, 화면천이 편집부(32)에서는 불필요한 화면을 삭제할 경우 또는 화면의 천이목표(targut screen for shifring)를 변경할 경우 이것에 관련되는 화면의 화면정보데이터를 자동적으로 수정한다.
Patent KR-20000070429-A (KR)
Title: 래치 회로
IPC: H03K3/012
Filed: 1998-01-27
Abstract: 2.5V의 전원 전압과 200mV의 전압 스윙을 가지는 차동 모드의 저전압 래치에 관한 것이다. 각각 반전 및 비반전 입력 단자와 반전 및 비반전 출력 단자를 가지는 두 개의 인버터가 이용된다. 비반전 출력 단자는 OR 구조의 입력에 연결되고, 반전 출력 단자는 또 다른 OR 구조의 다른 입력에 연결된다. 한 인버터의 입력 단자는 래치의 입력 단자를 형성한다. 다른 인버터의 입력 단자는 OR 구조의 출력 단자에 연결되고 래치의 출력을 형성한다. 인버터의 전원 전압은 주어진 시간에 따라 변화해서 단지 하나의 인버터만이 적절한 전원 전압을 가질 수 있다. 이 인버터는 래치의 출력을 제어한다. 이와 같이 래치의 기능이 수행된다.
Patent KR-20000070632-A (KR)
IPC: B01J31/14
Filed: 1998-01-15
Abstract: A free-flowing solid which does not self-ignite, comprising:a) at least one support component,b) at least one chemical compound which per se is self-igniting,c) at least one inert liquid andd) further components.
Patent KR-20000075555-A (KR)
Title: 유전자 서열화 기기 및 서열화 방법
IPC: C40B40/06
Filed: 1998-02-20
Abstract: 유전자 서열화 기기, 바이오 콤팩트 디스크 및 샘플제조방법이 발표된다. 일정 길이의 올리고누클레오티드가 제조되고 기술된 바이오 콤팩트 디스크 및 장치를 써서 유전자 서열화가 이루어진다.
Patent KR-20000075954-A (KR)
Title: N-hydroxy 4-sulfonyl butanamide compounds
IPC: C07D295/15
Filed: 1998-03-04
Abstract: A sulfonyl divalent aromatic or heteroaromatic ring hydroxamic acid compound that inter alia inhibits matrix metalloprotease activity is disclosed as are a treatment process that comprises administering a contemplated sulfonyl divalent aromatic or heteroaromatic ring hydroxamic acid compound in a MMP enzyme-inhibiting effective amount to a host having a condition associated with pathological matrix metalloprotease activity.
Patent KR-20000076102-A (KR)
Title: 전기충격 방지 구조를 구비한 액정표시소자
IPC: G09F9/30
Filed: 1998-03-09
Abstract: 적어도, 고저항 전극층(6)과, 액정(3)이 폴리머 매트릭스(4) 중에 미분산된 액정분산 폴리머층(2)으로 이루어지고, 상기한 고저항 전극층(6)의 표면저항은, 기온 25℃에서 상대습도가 50%일 때, 10 4 Ω/□ 이상, 10 8 Ω/□ 미만인 전기충격 방지 구조를 구비한 액정표시소자가 제공된다.
Patent KR-20010005960-A (KR)
Title: 중합체 조성물에서의 응력 레벨 측정 방법
IPC: G01N11/00
Filed: 1998-04-03
Abstract: 본 발명은 각각의 미립자가 강자성 또는 준강자성인 코팅이 제공된 비강자성 또는 비준강자성 코어를 포함하는 다수의 미립자 중합체 또는 예비중합체 조성물과 혼합하여 미립자가 조성물을 통해 실질적으로 균일하게 분산되어 있는 혼합물을 형성하는 것을 포함하는 소정 체적내에서 중합체 또는 예비중합체 조성물내의 응력 레벨을 측정하는 방법에 관한 것이다. 미립자는 소정 체적내에서 조성물내의 응력 레벨과 상관관계에 있는 측정가능한 자기 특성을 갖는다. 미립자의 자기 특성의 변화율을 측정하여 소정 체적내에서 조성물내의 응력 레벨을 측정한다.
Patent KR-20010012947-A (KR)
Title: 가정용 기구에 이용되는 신축자재 장치 및 그것의 조립방법
IPC: A47L9/24
Filed: 1998-06-04
Abstract: 본 발명의 가정용 기구에 이용되는 신축자재 장치(1; 41)은 외관(3) 속에서 팽팽하게 미끄러지는 내관(2)와, 슬리브(4; 44)와, 내관(2)와 외관(3) 사이에 배치되는 구속 부품(5)과, 추력 부품(6), 및 조작수단(7)을 포함한다.  상술한 신축자재 장치(1; 41)에서, 외관(3)과 결합된 관형 말단부(9; 49)는 수납부(niche; 12)를 형성하는 볼록부분(relief; 11)를 포함하고, 슬리브(4; 44)에는 수납부(12) 내에 삽입되고 공간(18)을 포함하는 융기부(15)가 설치되며, 상술한 공간(18) 속에는 구속 부품(5)과, 추력 부품(6), 및 스프링(21)이 충분하게 수용된다.  추력 부품(6)은 오목부를 포함한 폭-좁은 부분(20)이 제공된 길고 얇은 슬라이더(28)로 형성되고 조작수단(7)은 상술한 오목부와 스냅-온(snap-on) 결합되는 폭-좁아진 말단부(38)가 제공된 돌기 날개들(37)을 포함한다.
Patent KR-20010013245-A (KR)
IPC: C07D251/60
Filed: 1998-05-15
Abstract: Method for preparing melamine from urea via a high-pressure process in which solid melamine is obtained by transferring the melamine melt coming from the reactor to a vessel where the melamine melt is cooled with an evaporating cooling medium. The melamine melt comes from the melamine reactor at a temperature between the melting point of melamine and 450 °C and is sprayed into a cooling vessel, via spraying means, having an ammonia environment with an increased ammonia pressure and cooled by means of an evaporating cooling medium to form melamine powder. The melamine melt is thereby converted into melamine powder having a temperature of 270 °C or below after which the ammonia pressure is released and the melamine powder is cooled, at least for part of the cooling range, by the powder being set in motion mechanically and being cooled directly or indirectly and, if necessary, the melamine powder is cooled further.
Patent KR-20010080836-A (KR)
Title: Gas for controlling elastic valve and method of manufacturing the gas
Inventor: KANG HAN SIK
IPC: C09K5/04
Filed: 2000-01-17
Abstract: PURPOSE: Provided is a gas for controlling an extensible valve equipped with a bellows, which can control extension amount of the extensible valve exactly and contains R-11 and R-142b. CONSTITUTION: The gas for controlling the extensible valve is produced by a process comprising the steps of: (S10) making the R-11 and the R-142b saturated vapor state of 60deg.C; (S20) making the R-11 and the R-142b have a pressure of 0.4kgf/cm¬2 and 1.0kgf/cm¬2; (S30)(S40) injecting the R-11 and the R-142b into the vacuum bellows and then mixing. The mixture gas of the R-11 and the R-142b is controlled by heating and cooling at 5-15deg.C.
Patent KR-20000036320-A (KR)
Inventor: YONG DUG JOONG
IPC: E03B7/12
Filed: 2000-01-18
Abstract: PURPOSE: A semi-permanent switch circuit is provided to operate a winter burst preventer only under the sub-zero temperature. CONSTITUTION: A triac(3) is coupled with a heater(2) in serial and the gate terminal of the triac is coupled with a diac(4), a current limit resistance(5) and a thermistor(6) in serial. When the resistance value of the thermistor is less than 20Kohms, it is over the yield voltage. Thus, the gate of the triac receives voltage and the triac is turned on to feed current to the heater. When surrounding temperature is more than zero°C and the resistance value of the thermistor is more than 20Kohms, it isn't over the yield voltage. Thus, the triac is turned off with no voltage and current is not fed to the heater.