baber/WOPTO huggingface dataset:
Patent KR-200490199-Y1 (KR)
IPC: A23P30/10
Filed: 2019-02-18
Granted: 2019-10-10
Abstract: 본 고안은 두부 성형틀에 관한 것으로, 특히 두부를 성형틀로부터 분리할 때 망가져서 훼손되는 것을 최소화할 수 있는 분리형 나무 두부 성형틀에 관한 것이다. 이를 위해 본 고안은 사각의 판재로서 두부 성형시 탈수되는 물을 배출하기 위한 다수의 배출구멍이 형성되고, 가장자리 둘레를 따라서 상측으로 돌출된 이탈방지구가 형성되며, 상기 이탈방지구는 길이방향을 따라서 그 상측이 내측방향으로 경사된 안내경사부가 형성된 밑판체; 상부 및 하부가 개방된 사각의 함체로서 다수의 배출구멍이 형성되고, 그 측면 외곽이 상기 이탈방지구의 내측부위에 꼭맞게 삽입되는 크기를 가져서 흔들림이 방지되며, 상기 밑판체로부터 상측으로 분리되는 측벽체; 상기 측벽체의 상부로부터 삽입되어 내측에 위치하는 두부를 가압하여 탈수시킴과 동시에 성형하는 누름판;으로 구성된다.
Patent KR-200490260-Y1 (KR)
Title: 오디오 수집전달형 충전케이블
IPC: H04R1/08
Filed: 2019-03-05
Granted: 2019-10-21
Abstract: 본 고안은 사람이 얼굴에 가져다대고 말하는 통화 환경에 최적화된 스마트 디바이스를 위하여 수 미터 떨어진 곳의 사용자가 말하는 소리를 그 스마트 디바이스의 마이크에 근접 전달하는 기술로서, 스마트 디바이스를 충전하기 위해 필요한 충전케이블에 외부의 소리를 수집하여 주변에 전달하는 구성을 구비함에 따라 별도의 추가 장비 없이도 종래의 통화 최적형 스마트 디바이스를 위하여 수 미터 떨어진 곳의 사용자가 말하는 소리를 그 스마트 디바이스에 정확하게 전달함에 따라 디지털 비서 또는 인공지능 비서 기능을 원활하게 구현하도록 하는 기술에 관한 것이다. 본 고안에 따르면, 본체 하우징의 함몰홈에 본체 스피커를 장착함에 따라 스마트 디바이스의 디바이스 마이크에 대해 오디오 수집전달 본체가 수집한 소리를 근접 전달할 수 있는 장점이 있다.
Patent KR-200496422-Y1 (KR)
IPC: A61B17/70
Filed: 2020-08-28
Granted: 2023-01-27
Abstract: 본 발명은 개체 골격 내부 또는 골격 사이에 주입되는 지지부재에 관한 것이다. 상기 지지부재는, 상측 및 상기 상측과 마주하는 하측을 구비하는 본체; 상기 본체의 상기 상측에 형성되고, 도브테일 러그 형태를 가지는 제1 연결부; 상기 본체의 상기 하측에 형성되고 상기 제1 연결부에 대응되는 제2 연결부; 및 상기 본체의 일측에 형성되어 외부의 가이드 템플릿 플러그와 대응되게 접합하도록 하는 가이드 구조; 를 포함하고, 상기 지지부재의 상기 제1 연결부는 다른 한 지지부재의 제2 연결부가 서로 도브테일 매칭되어 연결되도록 하며, 상기 제1 연결부 전측은 상기 도브테일 러그에 구성된 제1 포지셔닝부를 더 포함하고, 상기 제2 연결부 전측은 형상 및 위치가 상기 제1 포지셔닝부와 대응되는 제2 포지셔닝부를 더 포함하며; 상기 제1 포지셔닝부는 포지셔닝 블록 포인트이고, 상기 제2 포지셔닝부는 상기 지지부재가 서로 포지셔닝 체결되도록 하는 포지셔닝 요홈인 것을 특징으로 한다.
Patent PH-22014000352-Y1 (PH)
Title: A cover for a steering wheel
Inventor: GO ALWIN T
IPC: B62D1/06
Filed: 2014-06-02
Abstract: The present utility model relates to a cover for a steering wheel a main collar having a curved top portion downwardly extending to a pair of opposed curved lower side portions, each of said opposed curved lower side portions having respective free ends, said respective free ends being spacedly disposed with each other thereby defining a gap therebetween; and an inner collar being attached to the inner side of said main collar, said inner collar being made of polyvinyl chloride (PVC) material in order to prevent the foul odor caused by the reaction of external elements such as perspiration with the use of the rubber material.
Patent PH-22014000699-Y1 (PH)
Title: System for monitoring movements in inventory levels
Inventor: RASUL-BERNARDO IBRAHIM JOSE
IPC: G06Q30/00
Filed: 2014-12-10
Abstract: A system for monitoring movements in inventory levels is disclosed. The system comprises a client device and a server device in communication with one another over a communication network such as that of the Internet Protocol (IP) type. Inventory count and inventory movement label information can be captured by an input/output component of the client device and can be processed and transmitted to the server device by computer-executable instructions that consist in an application module installed in the client device. The instructions are arranged to update an inventory count in an inventory record based on the inventory count information and the inventory movement label information from the client device, wherein the inventory movement label information can be selected from a group consisting of new stocks, sales, positive adjustments, negative adjustments, inbound transfers, and outbound transfers.
Patent PH-22016000618-Y1 (PH)
Title: Paper cup with embossed sleeve
Inventor: CO WARREN
IPC: B65D85/72
Filed: 2016-08-12
Abstract: The present utility model discloses paper cup with embossed sleeve adapted for containing hot beverage drinks comprising of a cup body being coated with polyethylene (PE) plastic film on the inner surfaces to protect the main material from wear and tear and keep it dry from the cup and a sleeve member attached and encircling the cup body. The embossed sleeve having plurality of embossments and embossed markings thereon and defining on the lower portion thereof is an air ingress portion allowing air inflow and trapping of air in between the sleeve and the cup body to make insulation more effective. The cup body is also made with leak-proof and stable bottom portion to make it stand on its own when filled or unfilled.
Patent PH-22017000175-Y1 (PH)
Title: Method of preparing jackfruit peel with squash jam
Inventor: BAYBAYANON MEILISSA SUHOT
IPC: A23L21/12
Filed: 2017-04-10
Abstract: The utility model relates to a method of preparing jackfruit peel with squash jam by cutting a jackfruit into halves, collecting a jackfruit pulp and jackfruit peel, dipping the jackfruit peel immediately in a calamansi solution, boiling the jackfruit peel until it becomes tender, slicing into smaller strips the jackfruit pulp and jackfruit peel, slicing, peeling, and cutting into small cubes a squash to from a squash cubes, boiling the squash cubes, mixing the jackfruit pulp, jackfruit peel and squash cubes until homogenized to create a fruit mixture, adding and mixing sugar using a 1:1 fruit mixture and sugar ratio, cooking the fruit mixture, and adding calamansi juice to the fruit mixture to create a jam.
Patent PH-22018000607-Y1 (PH)
Title: A process of making `imbao` or mud clams (anodontia edentula) sisig royale
Inventor: SABANG ROEL I
IPC: A22C29/04
Filed: 2018-06-27
Abstract: This utility model relates to a process of making imbao or mud clams (Anodontia edentula) sisig using effective amounts of imbao, ginger, garlic, onion bulb, green and red pepper, chili pepper, bay leaf, ground pepper, salt, vegetable oil and spring onion for garnishing comprising the steps of washing the mud clams or imbao, placing the mud clams or imbao in the microwave, setting the microwave for 3 minutes just enough to remove the imbao juice, setting aside the steamed imbao, sauteing the ginger until golden brown, gradually putting in the garlic, cubed onion bulb, bell pepper and chili pepper, adding the imbao meat, crushed bay leaf, ground pepper and salt, simmering the mixed ingredients for 1 minute, adding of calamansi juice, adding of coconut vinegar' transferring the cooked mud clams or imbao to a serving plate, topping the imbao or mud clams with spring onion and topping the imbao or mud clams with sunny side up egg.
Patent PH-22019050485-Y1 (PH)
Title: Method of preparing immunoreactive antibodies against entamoeba histolytica
Inventor: BUNDALIAN REYNALDO JR D L
IPC: C12Q1/04
Filed: 2019-10-16
Abstract: The present utility model is directed to a method of preparing immunoreactive and neutralizing antibodies against Entamoeba histolytica. The disclosed method is based on challenging an immunocompetent host and harvesting of immunoreactive antibodies produced.
Patent PH-22020000281-Y1 (PH)
Title: Process of producing canistel (pouteria campechiana) turmeric (curcurma longga) tea
Inventor: CHAVEZ MA ROVIE A
IPC: A23F3/00
Filed: 2020-06-22
Abstract: The process of producing canistel turmeric tea, said method comprises the selection of matured canistel fruit; wash the canistel fruit; drain the canistel fruit; peel the canistel fruit; spread the canistel fruit in flat sheet; dry canistel fruit in mechanical dryer; powder the dried c;anistel fruit; sift the powdered canistel fruit; select matured turmeric rhizomes; wash the turmeric rhizomes; drain the washed turmeric rhizomes; pair the turmeric rhizomes; shred the paired turmeric rhizomes; dry the shredded turmeric rhizomes; powder the dried turmeric rhizomes; sift the powdered turmeric rhizomes; measure 2 cups canistel fruit powder from sifted powdered canistel fruit and 1 cup turmeric powder from sifted powdered turmeric; mix measured powdered canistel fruit and turmeric, weigh 15 g of mixed powder; pack the weigh mixed powder into a tea bag; and seal the combined powder.
Patent BR-202014001070-Y1 (BR)
Title: Constructive provision introduced in vertical alignment support for equipment
Inventor: LUIZ ANTNIO MACEDO RAMOS
IPC: G09B1/02
Filed: 2014-01-16
Abstract: disposição construtiva introduzida em suporte alinhador vertical para equipamentos. o modelo de utilidade trata de uma disposição construtiva introduzida em suporte alinhador vertical para equipamentos, situado no setor tecnológico de equipamentos destinados ao ensino e pesquisa. sabe-se que os modelos existentes não possibilitam a versatilidade necessária para a rápida fixação dos elementos componentes, dificultando a adequada precisão nos resultados, bem como, dificultando a permanência dos mesmos nas posições pré-determinadas; além de dificultar uma mudança no posicionamento de componentes em função de variações de cada etapa de estudo. diante disso, caracteriza-se por compreender uma estrutura laminar com formato em “l” (1) dotada, em sua base (2), de um alargamento (3) e orifícios de fixação (4); bem como, em sua porção verticalizada (5), de uma abertura circular (6) e extremidade com prolongamento superior (7); além de ressaltos laterais (8) próximos à abertura (6). em uma variante configurativa, a estrutura (1) apresenta a porção verticalizada (5) sem o prolongamento superior (7), substituído por uma extremidade circular concêntrica (9); bem como, sem os ressaltos laterais (8).
Patent IT-212736-Z2 (IT)
IPC: A47J47/18
Filed: 1987-07-02
Granted: 1989-08-28
Abstract: The container is composed essentially of a body (1) made from plastic and of frustoconical shape, with a bottom (2) and an upper opening (3) which are circular, with a corresponding lid (4). The body (1) has two diametrically opposed projections (5) placed on the outer lateral surface (6), which are equipped with a slot (7) in which have been inserted the protuberances (8) placed at the ends (9) of the bail handle (10) made from plastic. The projections (5) are inserted in the middle of a pair of circular rings (11) and (12) parallel to the prominent upper rolled edge (13) in order to give the container greater strength and to be capable of applying the lid (4) there without deforming it. <IMAGE>
Patent IT-216961-Z2 (IT)
Inventor: ENZO BRUSASCO
IPC: E05B65/12
Filed: 1989-03-07
Granted: 1991-10-21
Abstract: PCT No. PCT/IT90/00020 Sec. 371 Date Sep. 9, 1991 Sec. 102(e) Date Sep. 9, 1991 PCT Filed Mar. 6, 1990 PCT Pub. No. WO90/10774 PCT Pub. Date Sep. 20, 1990.An electric lock actuator device (201), in particular for motor vehicles, comprising an electric motor (204) driving a recirculating ball worm screw unit (251, 260) for rectilinear movement of a cap element (264) slidable on a portion (207) of the frame (202) housing the motor (204) and adapted to act on a member (267) for locking and releasing the operation of a lock, and including a specific electronic control unit (27) for this electric motor (204), in which this electronic unit (27) includes a first integrated circuit (23) for distribution of electrical power supply for operation of the electric motor (204), and a second integrated circuit (25) for dealing with information signals relating to the operation of the motor (204), these integrated circuits (23, 25) being connected to a printed circuit (271) which is already utilised by slidable contact blades (270) having an end-of-stroke commutation function, fixed to the movement of this slidable cap (264), and which is housed in a portion (220) of the frame (202) of the device (201), which is integral with the portion (207) of the frame (202) housing the electric motor (204).
Patent IT-224834-Z2 (IT)
Title: perfezionamento di prolunga porta forbice per potatura ad uso agri-  colo.
IPC: A01C/
Filed: 1991-11-06
Granted: 1996-06-27
Abstract: Perfezionamento comprendente elementi tubolari atti ad infilarsi in un manicotto portato da uno degli elementi da agganciare alla sua estremità e a bloccarsi in altro apposito manicotto scorrevole sul primo.
Patent IT-222066-Z2 (IT)
Title: Dispositivo per uno stampo per la formatura per colata di mole abrasive
IPC: B42D/
Filed: 1991-12-04
Granted: 1994-12-30
Abstract: Il dispositivo (flangia) per uno stampo per la formatura per colata di mole abrasive (in particolare di mole atte alla lavorazione di superfici in marmo, in pietra ecc.) oggetto del presente trovato consiste in una serie di elementi di copertura (1, 2, 3, 4) uniti fra di loro che si inseriscono perfettamente negli incavi lasciati liberi tra le basette (per la formatura dei codoli d'attacco) ed una parte delle pareti interne delle vaschette di colata. Gli elementi di copertura (1, 2, 3, 4) sono uniti fra di loro da mezzi di collegamento (7, 9) che consentono un loro più rapido inserimento e disinserimento in detti incavi.
Patent IT-226597-Z2 (IT)
IPC: A41B/
Filed: 1992-05-19
Granted: 1997-06-24
Abstract: PCT No. PCT/IT92/00107 Sec. 371 Date Oct. 6, 1994 Sec. 102(e) Date Oct. 6, 1994 PCT Filed Aug. 26, 1992 PCT Pub. No. WO93/22942 PCT Pub. Date Nov. 25, 1993A brassi+E,gra e+EE re in which each cup (1,2), connected to both an elastic band (4) and a respective shoulder strap (7,8), consists, in its lower and lateral parts, of a continuous band (3,3') made of low-stretch fabric.
Patent IT-222912-Z2 (IT)
Title: Banco da esposiione refrigerato per rivendite, particolarmente per prodotti alimentari
IPC: F25B/
Filed: 1991-02-07
Granted: 1995-05-09
Abstract: Il banco refrigerato comprende una vasca coibentata coperta superiormente da una vetrina, un pianale ad altezza intermedia nella vasca, e una cella sottostante il ripiano. Ad estremità trasversalmente opposte del pianale sono definite rispettive aperture di comunicazione fra la zona della vasca al di sopra e quella al di sotto del pianale. La cella è delimitata da una parete verticale distanziata dal fondo della vasca per definire un vano comunicante con una prima di dette aperture, e da una parete orizzontale distanziata dal pianale per definire un'intercapedine comunicante sia con detto vano che con la seconda di dette aperture. Nel vano sono alloggiati mezzi scambiatori di calore e mezzi ventilatori per generare un flusso d'aria che percorre l'intercapedine, si diffonde sopra il pianale attraverso la seconda di dette aperture, e ritorna al vano attraverso la prima di dette aperture.
Patent CR-7320-A (CR)
Title: Tiofen. y tiazolsulfonamidas como agentes antineoplasicos
Inventor: ALFONSO DE DIOS
IPC: A61K31/38
Filed: 2004-04-23
Abstract: La presente invencion proporciona los compuestos de formula I (ver grafico)
Patent CR-9155-A (CR)
Title: PIRAZOLO (3,4-b) PIRIDINAS E INDAZOLES TERAPEUTICOS
Inventor: ROBERT M SCHELKUN
IPC: C07D231/56
Filed: 2007-05-29
Abstract: La presente invencion proporciona compuestos de la formula I en los que R2, R3, R4, R5, R6, R7, X y L tienen cualquiera de los valores definidos en la memoria descriptiva, y sales farmaceuticamente aceptables de los mismos, que son utiles como agentes en el tratamiento de trastornos y enfermedades del sistema nervioso central incluyendo el trastorno de deficit de atencion con hiperactividad, dolor neuropatico, incontinencia urinaria, ansiedad, depresion, y esquizofrenia y fibromialgia. Tambien se proporcionan composiciones farmaceuticas que comprenden uno o mas compuestos de la formula I.
Patent FR-1425851-A (FR)
IPC: C07C201/16
Filed: 1965-03-02
Granted: 1966-01-24
Abstract: Nitromethane is recovered from mixtures with higher nitroalkanes by adding to said mixtures sufficient water and C6- 8 alkane or cycloalkane to form an azeotropic mixture with said nitromethane, and heating the mixture to distil off said azeotrope.  The said azeotrope condenses into three layers, the lowest of which contains the nitromethane with minor amounts of water and alkane.  The water and alkane may be removed by further distillation up to 101.5 DEG  C.
Patent GB-327426-A (GB)
Title: Improvements in or relating to propelling apparatus applicable particularly to the propelling of lawn tennis bails and other game missiles
IPC: A63B69/40
Filed: 1929-01-01
Abstract: 327,426. Dunlop Rubber Co., Ltd., Lacoste, J. R., and Stuart, T. Jan. 1, 1929. Projecting appliances. - In a projecting- appliance for tennis balls &c. of the kind wherein a rotatable spring is flexed by engagement with a stop and on escaping therefrom strikes a ball to project it, the spring is carried by a sleeve rotatable about a fixed spindle. As shown in Figs. 1 and 2, the spring 1 is secured to a sleeve 2 rotatable by means of a handle 5 about a spindle 3 carried by a frame 4. The spring is flexed by the engagement of its free end with a stop comprising a roller 8<a> mounted on a pin 8 that is fixed in adjusted position within a slot 8<b> by means of a handle 8<c>. On escaping from the stop 8, the spring strikes a ball, retained within the end of an arcuate guide 10 by means of adjustable stops 10<d>. Balls 9 are fed by gravity into striking position from a magazine 11 comprising four vertically disposed, cylindrical chambers that carry the balls and are rotatable about a pin 11f into delivering position. The magazine is retained in its four operative positions by a spring-urged plunger 11<g> engaging shallow recesses in the pin 11<f>. To vary the trajectory of the balls, the flange 7<b> carrying the guide 10 and stop 8 is angularly adjustable about the spindle 3 and is fixed in actuated position by a handle 3<b>. The boss of the handle 5 is provided with arcuate slots 5b that receive the attaching screws 5a and allow of adjustment of the handle relatively to the sleeve 2. Backward rotation of the handle is prevented by a pawl 6<c> carried by the sleeve and co-operating with a ratchet wheel 6<a>. The vibrations of the spring 1 are damped by the interposition of compression springs 1<a> between it and a projection 1<b> on the sleeve. In a modification, the sleeve 2 is mounted in ball bearings on the spindle and is connected to the handle 5 through a pawl and ratchet gear. The apparatus is normally arranged in the position shown in Fig. 6 with relation to a wheeled base 12, in which position it is held by the base-members 12d engaging re-entrant slots in the cylindrical lower end of the frame 4. The apparatus is collapsed for storage purposes by removing the spindle 3 from the slot 4<a> in the frame, and securing it within a slot 4<d> at right angles thereto, the frame 4 being then rotated about the wheel axle into the position shown in Fig. 8. The frame 4 is locked in its operative or collapsed positions by bolt 12<b> that pass through the axles of the wheels and engage the members 12d.
Patent GB-363843-A (GB)
Title: Improvements in combination garment
IPC: A41C1/06
Filed: 1931-01-01
Abstract: 363,843. Combined corsets and brassiÞres. GOSSARD CO., H. W., 108, East Ohio Street, Chicago, U.S.A.-(As signees of Cunningham, K. E. ; 40, East Oak Street, Chicago, U.S.A.) Jan. 1, 1931. No. 72. Convention date, Aug. 29, 1930. [Class 141.] A brassiÞre comprising a front portion 15 adapted to cover the body across the busts is sewn or otherwise attached to the upper edge of a corset 5, and has end sections 16, 17, adapted to be crossed at the back, which carry elastic straps 26 adapted to be fastened to the back of the corset. In one form, the corset, which may be boned, is made of inelastic material 5 with elastic side portions 6, 7, hose suspenders 8, hooks 9 and eyes 10 at one side for fastening, and a portion 11 adapted to extend above the diaphragm of the wearer intermediate the busts. A gusset 12 at the top of the back facilitates added adjustment. The front portion 15 of the brassiÞre is made from inelastic soft material which is sewn to the corset, and the elastic straps 26 carry buttonhole tabs 27. Shoulder straps 34, 35, which may be made of elastic material, are attached to the front portion 15 and the end sections 16, 17.
Patent IS-6498-A (IS)
Inventor: DEMAIN AXEL
IPC: A61F13/511
Filed: 2002-08-13
Abstract: A polypropylene fibre including greater than 50% by weight of a first isotactic polypropylene produced by a metallocene catalyst, and from 5 to less than 50% by weight of a second isotactic polypropylene produced by a Ziegler-Natta catalyst.
Patent JP-S60160891-A (JP)
Inventor: JIEIMUZU FUREDERITSUKU UORUTAA
IPC: C12R1/19
Filed: 1985-01-04
Abstract: (57)【要約】本公報は電子出願前の出願データであるた め要約のデータは記録されません。
Patent CR-10171-A (CR)
Inventor: VIRGINIA L SMITH-SWINTOSKY
IPC: A61K/
Filed: 2008-07-21
Abstract: The present invention is a methods for neuroprotection, for treating an acute neurodegenerative disorder, for treating a chronic neurodegenerative disorder and/or for preventing neuron death or damage following brain, head and/or spinal cord trauma or injury comprising administering to a subject in need thereof a therapeutically effective amount of one or more novel benzo-fused heterocycle sulfamide derivatives of formula (I) and formula (II) as herein defined.
Patent CU-33625-A (CU)
Title: Analizador de hierro ah-1
Inventor: MEITIN CASAS JUAN JULIAN LORETO
IPC: G01T1/18
Filed: 1971-11-18
Abstract: El analizador de hierro AH-1 es un equipo de análisis por fluorescencia de rayo X utilizando fuentes radioactivas de Tritio-Zirconio y detectores Geiger- Muller, para determinar el contenido de hierro en el mineral laterítico. Consta de Cabeza contadora, fuente de alto voltaje amplificador y formador de pulsos y equipo contador de pulsos CP1.
Patent GB-1486721-A (GB)
Title: Multichannel signal-handling systems and methods for compensating for variations in operating characteristics of a plurality of signal-handling channels
IPC: G01N29/06
Filed: 1975-01-02
Abstract: 1486721 Multi-channel error compensation: ultrasonic camera STANFORD RESEARCH INSTITUTE 2 Jan 1975 [21 Oct 1974] 107/75 Headings G1G and G1U Variations in data transmission channel characteristics, such as zero offset and gain, are corrected at a receiver by applying to each channel a stored correction factor, the correction factors being updated periodically by transmitting reference signals over the channels and comparing the resulting signals at the receiver with pre-set values. The correction arrangement is described as applied to an ultrasonic camera 10, 14, Fig. 1, and cathode ray tube 16 display system of the type in which a two dimensional display 16 of an object 12 under examination is produced line-by-line by scanning 44 the stored 38 amplitudes of 192 camera transducers 30 synchronously with the horizontal sweep of the c.r.t. and moving the camera transducers 30 vertically (i.e. normally to the plane of the drawing) either mechanically 34 or electrically (not shown, Specification 1442717 referred to) synchronously with the vertical sweep of the c.r.t. As described zero offset correction (Figs. 6 and 7, not shown, illustrate gain, and both gain and zero offset, correction respectively) is applied at the receiver 8 by an adder 50 to which correction values are fed via a D/A converter 56, from a circulating store 54, 54 read-out synchronously with the horizontal sweep of the c.r.t. At the bottom of each vertical sweep of the transducers, the camera transmitter 22 is turned off thereby applying a zero reference signal to each transducer 30, a scan of the transducer outputs is made and the signals resulting at the output of adder 50 are compared 60 with a pre-set zero level 62, and if for any channel a difference is detected the corresponding correction value in the store 54, 55 is incremented or decremented by unity. Thus after a few complete frame scans, the stored correction values should stabilize, and further changes will only occur if the channel characteristics change. When (as in Fig. 7, not shown) both zero offset and gain are to be corrected, the above system is augmented by a second store storing gain correction factors which are updated by transmitting a non-zero reference signal, from an additional transmitter installed in the camera, at the top of each vertical sweep of the camer transducers 30. As described above, a correction cycle is initiated automatically at the end of each frame. Correction cycles could however be initiated manually, e.g. once per day.