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CRITICAL FREQUENCY [13 records]
Record 1 - internal organization data 2018-09-14
Record 1, English
Record 1, Subject field(s)
- Security
- Drugs and Drug Addiction
Record 1, Main entry term, English
- drug screening
1, record 1, English, drug%20screening
correct
Record 1, Abbreviations, English
Record 1, Synonyms, English
Record 1, Textual support, English
Record number: 1, Textual support number: 1 CONT
The timeframe for drug screening is critical in detecting drug use. The amount of time a particular drug remains in the body depends on several factors such as the frequency of use, how much of the drug was taken as well as the metabolism of the individual. 1, record 1, English, - drug%20screening
Record 1, French
Record 1, Domaine(s)
- Sécurité
- Drogues et toxicomanie
Record 1, Main entry term, French
- dépistage de drogues
1, record 1, French, d%C3%A9pistage%20de%20drogues
correct, masculine noun
Record 1, Abbreviations, French
Record 1, Synonyms, French
- détection de drogues 2, record 1, French, d%C3%A9tection%20de%20drogues
correct, feminine noun
Record 1, Textual support, French
Record 1, Spanish
Record 1, Campo(s) temático(s)
- Seguridad
- Drogas y toxicomanía
Record 1, Main entry term, Spanish
- detección de drogas
1, record 1, Spanish, detecci%C3%B3n%20de%20drogas
correct, feminine noun
Record 1, Abbreviations, Spanish
Record 1, Synonyms, Spanish
Record 1, Textual support, Spanish
Record 2 - internal organization data 2017-02-13
Record 2, English
Record 2, Subject field(s)
- Spacecraft
Record 2, Main entry term, English
- proximity communication equipment
1, record 2, English, proximity%20communication%20equipment
correct
Record 2, Abbreviations, English
- PCE 2, record 2, English, PCE
correct
Record 2, Synonyms, English
Record 2, Textual support, English
Record number: 2, Textual support number: 1 CONT
We present the modification of two ESA [European Space Agency] ground stations carried out in order to support the in-flight RF [Radio Frequency] validation of the Proximity Communication Equipment(PCE), part of the International Space Station(ISS). This subsystem plays a critical role during the docking of the Automated Transfer Vehicle(ATV), and has to be tested prior to each ATV launch, to ensure that the RF performance is as expected. For the check-out, an unmodulated signal is transmitted by the PCE during an ISS pass, and received by the two ground stations. Based on the strength of the received signal, the radiation characteristic of the complete PCE can be assessed, and compared with the nominal performance. The measurement process requires calibrating the receiving subsystem, including antenna, front-end and back-end equipment. The adopted calibration procedure, only relying on radio stars measurement, does not require the use of a calibrated source external to the ground station. 3, record 2, English, - proximity%20communication%20equipment
Record 2, French
Record 2, Domaine(s)
- Engins spatiaux
Record 2, Main entry term, French
- système de communication PCE
1, record 2, French, syst%C3%A8me%20de%20communication%20PCE
correct, masculine noun
Record 2, Abbreviations, French
Record 2, Synonyms, French
- système PCE 2, record 2, French, syst%C3%A8me%20PCE
correct, masculine noun
Record 2, Textual support, French
Record number: 2, Textual support number: 1 CONT
Le système de communications PCE (Proximity Communication Equipment) a été développé et intégré à Toulouse par EADS [European Aeronautic Defence Space] Astrium, dans le cadre du programme ATV [véhicule de transfert automatique] de l'Agence Spatiale Européenne, sous responsabilité d'EADS SPACE Transportation qui est le maître d'œuvre du développement et de la construction du segment spatial de l'ATV. Le PCE est destiné à assurer les communications de proximité pour les 30 derniers kilomètres de vol du futur véhicule cargo européen ATV à son approche de la Station spatiale internationale (ISS). [...] Le PCE est un sous-ensemble intégré. Il est constitué de deux chaînes de communications en bande S, entièrement redondantes. Il comprend deux transpondeurs à spectre étalé, deux équipements de gestion de protocoles CCSDS [Consultative Committee for Space Data Systems] et des équipements radio fréquence. Le PCE sera installé dans le module Zvezda de l'ISS et sera opérationnel durant la phase dite «de proximité» correspondant aux 30 derniers kilomètres du vol ATV et à l'exercice délicat de son arrimage à la Station. Ce rendez-vous orbital automatique représentera une première européenne. Parmi l'ensemble des données de commande et de contrôle qu'il transmettra dans le cadre de sa mission de communications, le PCE fournira à l'ATV les informations de position GPS [système mondial de localization] nécessaires à la navigation relative vers la Station spatiale internationale (ISS). À une distance de 500 m et jusqu'à l'arrimage, la navigation se poursuivra à l'aide d'instruments laser, d'abord avec un télégoniomètre puis avec un vidéomètre pour les phases finales. 3, record 2, French, - syst%C3%A8me%20de%20communication%20PCE
Record 2, Spanish
Record 2, Textual support, Spanish
Record 3 - internal organization data 2016-02-25
Record 3, English
Record 3, Subject field(s)
- Optics
Record 3, Main entry term, English
- Talbot's law 1, record 3, English, Talbot%27s%20law
Record 3, Abbreviations, English
Record 3, Synonyms, English
- Talbot law 2, record 3, English, Talbot%20law
Record 3, Textual support, English
Record number: 3, Textual support number: 1 DEF
The apparent brightness of an object viewed through a slotted-disk, rotating above a critical frequency, is proportional to the ratio of the angular aperture of the open to the opaque sectors. 2, record 3, English, - Talbot%27s%20law
Record 3, French
Record 3, Domaine(s)
- Optique
Record 3, Main entry term, French
- loi de Talbot
1, record 3, French, loi%20de%20Talbot
correct, feminine noun
Record 3, Abbreviations, French
Record 3, Synonyms, French
Record 3, Textual support, French
Record 3, Spanish
Record 3, Campo(s) temático(s)
- Óptica
Record 3, Main entry term, Spanish
- ley de Talbot
1, record 3, Spanish, ley%20de%20Talbot
correct, feminine noun
Record 3, Abbreviations, Spanish
Record 3, Synonyms, Spanish
Record 3, Textual support, Spanish
Record 4 - internal organization data 2012-04-05
Record 4, English
Record 4, Subject field(s)
- Acoustics (Physics)
Record 4, Main entry term, English
- critical bandwidth
1, record 4, English, critical%20bandwidth
correct
Record 4, Abbreviations, English
Record 4, Synonyms, English
- critical band 2, record 4, English, critical%20band
correct
Record 4, Textual support, English
Record number: 4, Textual support number: 1 DEF
The critical difference between the frequency limits of a band containing the useful frequency components of a signal. 3, record 4, English, - critical%20bandwidth
Record number: 4, Textual support number: 1 CONT
The notion of critical bands, introduced by Fletcher(1940), explains the masking of a narrow band(sinusoidal) signal by a wideband noise source... One can think of a critical band as a frequency selective "channel" of psychoacoustic processing; only noise falling within the critical bandwidth can contribute to the masking of a narrow band signal. The mammalian auditory system consists of a whole series of critical bands, each filtering out a specific portion of the audio spectrum. 4, record 4, English, - critical%20bandwidth
Record 4, Key term(s)
- critical BW
Record 4, French
Record 4, Domaine(s)
- Acoustique (Physique)
Record 4, Main entry term, French
- bande critique
1, record 4, French, bande%20critique
correct, feminine noun, standardized
Record 4, Abbreviations, French
Record 4, Synonyms, French
- groupe de fréquences 2, record 4, French, groupe%20de%20fr%C3%A9quences
see observation, masculine noun
Record 4, Textual support, French
Record number: 4, Textual support number: 1 DEF
bande critique : Bande de fréquences la plus large au-delà de laquelle certaines caractéristiques de l'audition ne sont plus modifiées (par exemple effet de masque) alors que d'autres sont modifiées (sonie augmentant avec la largeur de bande quand on maintient constante l'intensité acoustique). [Terme et définition normalisés par l'AFNOR et reproduits avec son autorisation.] 3, record 4, French, - bande%20critique
Record number: 4, Textual support number: 1 OBS
Le terme «groupe de fréquences» est parfois utilisé pour désigner la bande critique. [Justification reproduite avec l'autorisation de l'AFNOR.] 3, record 4, French, - bande%20critique
Record 4, Key term(s)
- bande de fréquences critiques
Record 4, Spanish
Record 4, Textual support, Spanish
Record 5 - internal organization data 2012-01-12
Record 5, English
Record 5, Subject field(s)
- Satellite Telecommunications
- Radar, Radio Guidance and Goniometry
Record 5, Main entry term, English
- feed chain
1, record 5, English, feed%20chain
correct
Record 5, Abbreviations, English
Record 5, Synonyms, English
Record 5, Textual support, English
Record number: 5, Textual support number: 1 CONT
A critical element in the feed chain is the primary feed horn which, in a high-capacity communications system, must provide efficient illumination of the antenna and good crosspolar response over both the receive and transmit frequency boards. 1, record 5, English, - feed%20chain
Record 5, French
Record 5, Domaine(s)
- Télécommunications par satellite
- Radar, radioguidage et radiogoniométrie
Record 5, Main entry term, French
- chaîne d'alimentation
1, record 5, French, cha%C3%AEne%20d%27alimentation
correct, feminine noun
Record 5, Abbreviations, French
Record 5, Synonyms, French
Record 5, Textual support, French
Record number: 5, Textual support number: 1 CONT
Outre le gain d’investissement, la suppression de cet onduleur améliore de 15 % le rendement de la chaîne d’alimentation sans interruption. 1, record 5, French, - cha%C3%AEne%20d%27alimentation
Record 5, Spanish
Record 5, Textual support, Spanish
Record 6 - internal organization data 2010-03-12
Record 6, English
Record 6, Subject field(s)
- Radio Waves
Record 6, Main entry term, English
- maximum usable frequency factor 1, record 6, English, maximum%20usable%20frequency%20factor
Record 6, Abbreviations, English
Record 6, Synonyms, English
- MUF factor 2, record 6, English, MUF%20factor
correct
Record 6, Textual support, English
Record number: 6, Textual support number: 1 CONT
Since the ionosphere lying over the great circle determines the mode of propagation, a method for determining the MUF over that path suggests itself : we must first determine the critical frequency at the midpoint of the path at a particular layer height. Knowing the path length will enable us to determine what the MUF factor will be. 3, record 6, English, - maximum%20usable%20frequency%20factor
Record 6, French
Record 6, Domaine(s)
- Ondes radioélectriques
Record 6, Main entry term, French
- facteur de fréquence maximale utilisable
1, record 6, French, facteur%20de%20fr%C3%A9quence%20maximale%20utilisable
correct, masculine noun
Record 6, Abbreviations, French
Record 6, Synonyms, French
Record 6, Textual support, French
Record 6, Spanish
Record 6, Campo(s) temático(s)
- Ondas radioeléctricas
Record 6, Main entry term, Spanish
- factor de máxima frecuencia utilizable
1, record 6, Spanish, factor%20de%20m%C3%A1xima%20frecuencia%20utilizable
correct, masculine noun
Record 6, Abbreviations, Spanish
Record 6, Synonyms, Spanish
Record 6, Textual support, Spanish
Record number: 6, Textual support number: 1 DEF
Relación entre la frecuencia máxima utilizable y la frecuencia crítica en el punto medio del salto. 1, record 6, Spanish, - factor%20de%20m%C3%A1xima%20frecuencia%20utilizable
Record number: 6, Textual support number: 1 OBS
símbolo: Md; en una transmisión de simple salto. 1, record 6, Spanish, - factor%20de%20m%C3%A1xima%20frecuencia%20utilizable
Record 7 - internal organization data 2009-11-16
Record 7, English
Record 7, Subject field(s)
- Telecommunications
- Radio Waves
Record 7, Main entry term, English
- critical frequency
1, record 7, English, critical%20frequency
correct
Record 7, Abbreviations, English
Record 7, Synonyms, English
Record 7, Textual support, English
Record number: 7, Textual support number: 1 CONT
The critical frequency... is the highest frequency that can be reflected when a signal strikes the ionosphere as a vertical(90° with respect to the surface) incident wave. 2, record 7, English, - critical%20frequency
Record 7, French
Record 7, Domaine(s)
- Télécommunications
- Ondes radioélectriques
Record 7, Main entry term, French
- fréquence critique
1, record 7, French, fr%C3%A9quence%20critique
correct, feminine noun
Record 7, Abbreviations, French
Record 7, Synonyms, French
Record 7, Textual support, French
Record 7, Spanish
Record 7, Campo(s) temático(s)
- Telecomunicaciones
- Ondas radioeléctricas
Record 7, Main entry term, Spanish
- frecuencia crítica
1, record 7, Spanish, frecuencia%20cr%C3%ADtica
correct, feminine noun
Record 7, Abbreviations, Spanish
Record 7, Synonyms, Spanish
Record 7, Textual support, Spanish
Record number: 7, Textual support number: 1 DEF
Frecuencia máxima reflejada por la capa F2 con incidencia vertical. 1, record 7, Spanish, - frecuencia%20cr%C3%ADtica
Record 8 - internal organization data 2007-02-15
Record 8, English
Record 8, Subject field(s)
- Aircraft Piloting and Navigation
- Air Safety
- Aerospace Equipment (Military)
Record 8, Main entry term, English
- flight termination system
1, record 8, English, flight%20termination%20system
correct
Record 8, Abbreviations, English
Record 8, Synonyms, English
Record 8, Textual support, English
Record number: 8, Textual support number: 1 CONT
At the very least, the UAV [unmanned aerial vehicle] should have a fail-safe flight termination system that is automatically activated in the event of a critical system failure or loss of radio frequency link. 1, record 8, English, - flight%20termination%20system
Record 8, French
Record 8, Domaine(s)
- Pilotage et navigation aérienne
- Sécurité (Transport aérien)
- Matériel aérospatial (Militaire)
Record 8, Main entry term, French
- système d'interruption de vol
1, record 8, French, syst%C3%A8me%20d%27interruption%20de%20vol
correct, masculine noun
Record 8, Abbreviations, French
Record 8, Synonyms, French
Record 8, Textual support, French
Record number: 8, Textual support number: 1 CONT
Un véhicule aérien non habité doit être au moins doté d'un système d'interruption de vol à mise en fonction automatique en cas de panne de système critique ou de perte de liaison radio. 1, record 8, French, - syst%C3%A8me%20d%27interruption%20de%20vol
Record 8, Spanish
Record 8, Textual support, Spanish
Record 9 - internal organization data 2004-01-19
Record 9, English
Record 9, Subject field(s)
- Telecommunications Transmission
Record 9, Main entry term, English
- vertical ionospheric sounding
1, record 9, English, vertical%20ionospheric%20sounding
correct
Record 9, Abbreviations, English
Record 9, Synonyms, English
Record 9, Textual support, English
Record number: 9, Textual support number: 1 CONT
Vertical incident sounding uses a collocated transmitter and receiver and involves directing a range of frequencies vertically to the ionosphere and measuring the values of the reflected returned signals to determine the effective ionosphere layer altitude. This technique is also used to determine the critical frequency. 2, record 9, English, - vertical%20ionospheric%20sounding
Record 9, French
Record 9, Domaine(s)
- Transmission (Télécommunications)
Record 9, Main entry term, French
- sondage ionosphérique vertical
1, record 9, French, sondage%20ionosph%C3%A9rique%20vertical
correct, masculine noun
Record 9, Abbreviations, French
Record 9, Synonyms, French
- sondage vertical de l'ionosphère 2, record 9, French, sondage%20vertical%20de%20l%27ionosph%C3%A8re
correct, masculine noun
- sondage vertical 3, record 9, French, sondage%20vertical
correct, masculine noun
Record 9, Textual support, French
Record number: 9, Textual support number: 1 CONT
La recherche sur l'ionosphère est importante non seulement pour comprendre la physique de la haute atmosphère, mais aussi pour la propagation radio dans l'ionosphère. C'est pourquoi il a été mis en place en Indonésie un réseau de sondage ionosphérique qui comprend six ionosondes numériques. Les données fournies chaque minute par ces ionosondes, sous forme d'ionogrammes numériques à haute résolution temporelle, seront disponibles. Ces ionogrammes à haute résolution fourniront des renseignements utiles sur les processus et les irrégularités ionosphériques ainsi que pour les radiocommunications à haute fréquence (HF). Des observations par sondages ionosphériques verticaux couvrant un cycle solaire permettront d'élaborer un modèle de prévision pour les radiocommunications à haute fréquence. Grâce à la collaboration entre l'Australie et l'Indonésie, l'exactitude des prévisions de fréquences a pu être améliorée grâce à la gestion en temps réel des fréquences. Cette activité est appuyée par un système de sondage oblique. 1, record 9, French, - sondage%20ionosph%C3%A9rique%20vertical
Record number: 9, Textual support number: 2 CONT
Historiquement, l'ionosphère a donc été divisée en couches distinctes, la première à avoir été détectée étant la région E (couche de Kennelly-Heaviside). Par ordre alphabétique, on a ensuite la couche F située au-dessus de la couche E. La couche F se subdivise généralement en deux couches, la couche F1 située vers 170 km et la couche F2 située au-delà de 250 km. La couche D, située entre 60 et 90 km échappe au sondage vertical (méthode des échos). Pour la détecter, on emploie des sondages obliques utilisant des fréquences plus petites (grandes longueurs d'onde). 4, record 9, French, - sondage%20ionosph%C3%A9rique%20vertical
Record number: 9, Textual support number: 3 CONT
À partir d'un sondage vertical de l'ionosphère on obtient un ionogramme sur lequel on peut identifier les paramètres caractéristiques du profil ionosphérique [...] 2, record 9, French, - sondage%20ionosph%C3%A9rique%20vertical
Record number: 9, Textual support number: 1 PHR
Télésondage ionosphérique. 5, record 9, French, - sondage%20ionosph%C3%A9rique%20vertical
Record 9, Spanish
Record 9, Textual support, Spanish
Record 10 - internal organization data 2003-11-07
Record 10, English
Record 10, Subject field(s)
- Radio Transmission and Reception
Record 10, Main entry term, English
- ultra-wideband emission
1, record 10, English, ultra%2Dwideband%20emission
correct
Record 10, Abbreviations, English
Record 10, Synonyms, English
- UWB emission 2, record 10, English, UWB%20emission
correct
Record 10, Textual support, English
Record number: 10, Textual support number: 1 DEF
Any emission whose fractional bandwidth is greater than 0.25 regardless of the center frequency or the signal time-bandwidth product. 1, record 10, English, - ultra%2Dwideband%20emission
Record number: 10, Textual support number: 1 CONT
The main concern regarding UWB emissions is the potential interference that they could cause to the "incumbents" in the frequency domain as well as to specific critical wireless systems that provide an important public service... 2, record 10, English, - ultra%2Dwideband%20emission
Record 10, Key term(s)
- ultra wideband emission
- ultrawideband emission
Record 10, French
Record 10, Domaine(s)
- Émission et réception radio
Record 10, Main entry term, French
- émission à bande ultra large
1, record 10, French, %C3%A9mission%20%C3%A0%20bande%20ultra%20large
proposal, feminine noun
Record 10, Abbreviations, French
Record 10, Synonyms, French
- émission à ultra large bande 1, record 10, French, %C3%A9mission%20%C3%A0%20ultra%20large%20bande
proposal, feminine noun
Record 10, Textual support, French
Record 10, Spanish
Record 10, Textual support, Spanish
Record 11 - external organization data 1994-12-12
Record 11, English
Record 11, Subject field(s)
- Nuclear Fission Reactors
- Compartment - Canadian Nuclear Safety Commission
Record 11, Main entry term, English
- critical crack length
1, record 11, English, critical%20crack%20length
correct
Record 11, Abbreviations, English
Record 11, Synonyms, English
Record 11, Textual support, English
Record number: 11, Textual support number: 1 CONT
Massive failure of all pressure vessels shall be analyzed unless it can be demonstrated that such a failure is of an acceptably low expected frequency of occurrence. If this is to be achieved, the following shall be taken as minimum requirements :... a critical crack length such that a detectable leak will occur at normal operating pressure well in advance of the critical crack length being reached. 1, record 11, English, - critical%20crack%20length
Record 11, French
Record 11, Domaine(s)
- Réacteurs nucléaires de fission
- Tiroir - Commission canadienne de sûreté nucléaire
Record 11, Main entry term, French
- longueur de fissure critique
1, record 11, French, longueur%20de%20fissure%20critique
feminine noun
Record 11, Abbreviations, French
Record 11, Synonyms, French
Record 11, Textual support, French
Record number: 11, Textual support number: 1 CONT
Il faut faire une analyse d'une défaillance majeure de tous les appareils sous pression à moins qu'on puisse démontrer que la fréquence prévue d'une telle défaillance soit assez faible pour être acceptable. Pour qu'une telle démonstration soit valable, les exigences minimales suivantes doivent être satisfaites : [...] il est défini une longueur de fissure critique telle que sous la pression normale d'exploitation la fuite soit détectable bien avant que la fissure atteigne une telle longueur. 1, record 11, French, - longueur%20de%20fissure%20critique
Record 11, Spanish
Record 11, Textual support, Spanish
Record 12 - internal organization data 1992-01-08
Record 12, English
Record 12, Subject field(s)
- Pest Control Equipment
- Mechanical Construction
Record 12, Main entry term, English
- dribble nozzle
1, record 12, English, dribble%20nozzle
correct
Record 12, Abbreviations, English
Record 12, Synonyms, English
- dribble-type nozzle 2, record 12, English, dribble%2Dtype%20nozzle
correct
Record 12, Textual support, English
Record number: 12, Textual support number: 1 CONT
A special dribble-type nozzle, fitted to a vibrating unit operated by a small direct-current electric motor, has been used to spray where drift control is critical. The nozzle is oscillated at a high frequency to produce a fan-spray pattern. 2, record 12, English, - dribble%20nozzle
Record 12, French
Record 12, Domaine(s)
- Matériel de protection des végétaux
- Construction mécanique
Record 12, Main entry term, French
- buse oscillante
1, record 12, French, buse%20oscillante
correct, feminine noun
Record 12, Abbreviations, French
Record 12, Synonyms, French
Record 12, Textual support, French
Record number: 12, Textual support number: 1 CONT
On utilise la buse oscillante, munie d'un vibrateur actionné par un petit moteur électrique à courant continu, lorsqu'il est très important d'éviter la dérive du brouillard. La buse oscille à haute fréquence et donne un jet en éventail. 2, record 12, French, - buse%20oscillante
Record 12, Spanish
Record 12, Textual support, Spanish
Record 13 - internal organization data 1984-08-22
Record 13, English
Record 13, Subject field(s)
- Radio Broadcasting
- Radiotelephony
Record 13, Main entry term, English
- cellular mobile radio
1, record 13, English, cellular%20mobile%20radio
correct
Record 13, Abbreviations, English
Record 13, Synonyms, English
Record 13, Textual support, English
Record number: 13, Textual support number: 1 CONT
cellular mobile radio differs from previous mobile radio designs in two critical areas :frequency reuse and cell splitting. 1, record 13, English, - cellular%20mobile%20radio
Record 13, French
Record 13, Domaine(s)
- Radiodiffusion
- Radiotéléphonie
Record 13, Main entry term, French
- radiotéléphone mobile cellulaire
1, record 13, French, radiot%C3%A9l%C3%A9phone%20mobile%20cellulaire
proposal, masculine noun
Record 13, Abbreviations, French
Record 13, Synonyms, French
- radiotéléphone mobile à cellules 1, record 13, French, radiot%C3%A9l%C3%A9phone%20mobile%20%C3%A0%20cellules
proposal, masculine noun
Record 13, Textual support, French
Record 13, Spanish
Record 13, Textual support, Spanish
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