Ultrasonic Transmitters Research Articles

Modeling NDT piezoelectric ultrasonic transmitters

Ultrasonic NDT applications are frequently based on the spike excitation of piezoelectric transducers by means of efficient pulsers which usually include a power switching device (e.g. SCR or MOS-FET) and some rectifier components. In this paper we present an approximate frequency domain electro-acoustic model for pulsed piezoelectric ultrasonic transmitters which, by integrating partial models of the different stages (driving electronics, tuning/matching networks and broadband piezoelectric transducer), allows the computation of the emission transfer function and output force temporal waveform. An approximate frequency domain model is used for the evaluation of the electrical driving pulse from the spike generator. Tuning circuits, interconnecting cable and mechanical impedance matching layers are modeled by means of transmission lines and the classical quadripole approach. The KLM model is used for the piezoelectric transducer. In addition, a PSPICE scheme is used for an alternative simulation of the broadband driving spike, including the accurate evaluation of non-linear driving effects. Several examples illustrate the capabilities of the specifically developed software.

Acoustic matching material, method of manufacture thereof, and ultrasonic transmitter using acoustic matching material

An acoustic matching material (1) is used to match the acoustic impedance of a first object to that of a sound object when sound is transmitted from the first object to the second object. The acoustic matching material (1) includes a plurality of minute pieces (2), at least one of which is coupled to another piece (2) to form a gap in the acoustic matching material (1).

Ultrasonic tracking reveals multiple behavioural modes of snapper (Pagrus auratus) in a temperate no-take marine reserve

Abstract Interactions between marine reserve populations and non-reserve populations of exploited fishes have generally been modelled using simplistic assumptions about behaviour. Consequently, there is a recognized need for better information on fish movement behaviour at the appropriate spatial scales to generate more realistic interaction models. Automated ultrasonic tracking of marine fish, applied in this study, offers the potential to continuously track individuals for periods of up to several years within the study area. Snapper (Pagrus auratus) (FL: 33–68 cm) were surgically implanted with individually coded ultrasonic transmitters to monitor their movement within the Cape Rodney to Okakari Point Marine Reserve in northeast New Zealand from October 2001 to September 2002. The range of movement patterns observed includes some fish resident for the entire tracking period, while others were more mobile. Of the latter group, some fish left the array permanently while others returned after up to 83 days of continuous absence. Nearly all fish showed some level of site fidelity for varying periods of the time they were tracked. Fish activity peaked in the summer, when highest densities are known to occur. Results suggest that snapper behaviour is variable, and that patterns of habitat utilization vary between fish and also seasonally. Such a complex range of behaviours may be a key component for achieving desirable outcomes for both conservation and fisheries in marine reserves.

Behavior and mortality of caught-and-released bonefish ( Albula spp.) in Bahamian waters with implications for a sustainable recreational fishery

Bonefish ( Albula spp.) are a widely distributed group of morphologically indistinguishable marine fish species, that provide a recreational sport fishery, that is important for many local economies. Although the majority of angled bonefish are released following capture, little is known about their behavior or post-release survival. Using ultrasonic transmitters and small visual floats, we assessed behavior and mortality of bonefish following catch-and-release angling at spring water temperatures (25.5–27.3 °C) in two regions of the Bahamas with differing shark abundances. All observed mortality occurred within 30 min of release and was a direct result of predation by sharks. In the low shark abundance areas, all released bonefish survived, whereas in the high shark abundance areas, some mortality (39%) was observed. Exhaustively angled fish exposed to air had problems maintaining equilibrium following release. These fish typically spent substantial periods of the first 30 min post-release remaining stationary, then moved in rapid bursts. The results of this study, highlight the benefits of angling and releasing bonefish quickly, minimizing handling and particularly air exposure. Furthermore, when shark predation threat is high, anglers should avoid releasing bonefish in the immediate area. The conservation of exploited recreational bonefish fisheries will depend upon the development and dissemination of science-based catch-and-release strategies.

A simple device for detecting impact time in impact-echo testing of concrete

The objective of this paper is to describe a simple device for detecting the time of an impact and to demonstrate its efficiency in measuring the depth of surface-opening cracks in concrete. Surface-opening cracks in concrete are relatively deep so that a mechanical impact instead of an ultrasonic transmitter is used to generate stress waves with enough energy for successful evaluation. A technique called the time-of-flight diffraction technique with impact-generated stress waves is an efficient method for detection of surface-opening cracks in concrete. Because the initial time of the impact is unavailable in a mechanical impact device, two receivers are employed in the test. One of the receivers is used to determine the time of the impact indirectly. The present study developed a simple device to record the time of impact initiation. The device comprises a conductive impact device, a sensing film, and an auxiliary circuit. With the device, stress waves are generated and the time of impact is detected so that the evaluation work needs only a single receiver. Laboratory studies were carried out on concrete specimens containing cracks with depths of 0.158 and 0.90 m. Field studies were performed on a dam damaged by an earthquake. Experimental results show that the new device can be used to accurately determine the crack depth in concrete. Using the device, the cost and effort for evaluation and signal analysis are reduced, which largely enhances the evaluation efficiency.

A preliminary telemetry study of the migration of silver European eel (Anguilla anguilla L.) in the River Mosel, Germany

Abstract – To study the behaviour of silver eels (Anguilla anguilla L.) during their downstream migration, particularly near a hydroelectric power dam, we tagged nine eels with ultrasonic transmitters and tracked their paths in the River Mosel, Germany. The onset of migration coincided with the first flood event that followed the full moon but was independent of daytime, because migration and turbine passage occurred during both day and night. During migration eels swam actively downstream with a velocity of 0.3–1.2 m · s−1. When migrating eels arrived at the dam, they either passed through the turbines immediately or stayed upstream of the powerhouse for up to 8 days, showing a characteristic circling behaviour. Circling eels repeatedly approached the trashrack, sprinted upstream, and finally passed through the turbines with the next high water discharge. These observations are discussed with regard to the design of appropriate downstream passage facilities.

Residence Time and Seasonal Movements of Juvenile Coho Salmon in the Ecotone and Lower Estuary of Winchester Creek, South Slough, Oregon

Abstract The juvenile life history of coho salmon Oncorhynchus kisutch in the stream−estuary ecotone of Winchester Creek, South Slough, Oregon, was investigated in 1999–2001. Seines and a rotary screw trap were used to capture fish for dye-marking, and residence time within the ecotone was determined for recaptured marked fish. In the lower estuary, ultrasonic transmitters were used to document residence time and patterns of movement for smolts migrating to the ocean. Nearly half of each brood year moved to the estuary as subyearlings. A portion of age-0 juveniles that moved downstream during spring lived in the ecotone through summer for up to 8 months, then most moved back upstream to overwinter. Fish that moved to the ecotone during fall and winter had mean minimum residence times of 48 d in 1999 and 64 d in 2000. Some of the fish that moved to the ecotone during fall and winter moved into an off-channel beaver pond and resided there for a mean of 49 d. Spring age-1 smolts had a mean minimum residence ...

보일러내 열 전달 효율 개선을 위한 초음파발신기 개발

보일러나 열교환기의 관 벽에 부착되는 스케일 방지용으로 설계된 초음파 발신기는 전기적 에너지를 초음파로 변환시켜주는 자왜소자와 발생된 초음파를 부하매질에 전달하는 도파봉으로 구성된다. 본 논문에서는 진동자로 사용되는 자왜소자의 형상설계와 진동자에서 발생된 초음파를 증폭시켜 부하매질로 전달하기 위한 몇 가지 형태의 도파봉에 대해 이론해석을 수행하여 필요한 사양을 도출하였다. 최종적인 도파봉의 길이는 음압 측정을 통해 선정하였다. 마지막으로 제작된 초음파발신기를 사용하여 보일러와 유사한 조건에서 스케일 방지효과를 확인하였다. Ultrasonic transmitter used for scale prevention in boiler or heat exchanger is composed of the magnetostrictive material which transforms electric energy into ultrasonic wave and the horn which amplifies generated ultrasonic wave and transfers it into medium loaded. In this paper, we have performed the shape design for magnetostrictive material and analyzed a few type of horns which amplify generated ultrasonic wave and found each solution theoretically. Final length of the horn has been determined by measuring the sound pressure in medium between theoretical value and experience data. At last we have given the results of our study for the effects of ultrasonic wave irradiated by manufactured ultrasonic transmitter on preventing scale deposition on test pipe under the similar condition to boiler.

전역 초음파 센서 시스템을 이용한 이동 로봇의 자기 위치 추정

A global ultrasonic sensor system for self-localization of a mobile robot is proposed in this paper. The global ultrasonic sensor system consists of three or more ultrasonic transmitters fixed at some positions in the world coordinate and receivers in the moving coordinate of a mobile robot. In this global sensor system it is easy to get state vector of the mobile robot in the world coordinate from the distance information between each ultrasonic transmitter and receiver. An extended kalman filter algorithm is used to process the noisy ultrasonic signal and to estimate the state vector. In case of using several independent ultrasonic transmitters, it is necessary to avoid the cross talk among the ultrasonic waves and to synchronize between each ultrasonic transmitter and receiver. The small sized radio frequency modules are adopted to solve the cross talk and the synchronization problem Computer simulation and experiments are carried out to verify the effectiveness of the proposed ultrasonic sensor system.

A Modified Downrigger for Detecting Radio Transmitters in Deep Water

Abstract The advantages and disadvantages of aerial (i.e., through the air–water interface) and underwater tracking of radio-tagged free-swimming fish are compared. A novel device is described that can be used to detect radio signals from depths exceeding the detection range of aerial antennas. This device can be used in small, confined bodies of water to track seasonal movements of fish into deep water, to identify locations of lost or expelled transmitters, to monitor relatively immobile benthic species, and to determine swimming or suspended depth while retaining several other advantages associated with the use of radio (versus ultrasonic) transmitters. The device is inexpensive, simple to construct, and easy to use with any commercially available telemetry receiver.

Distribution and Movement of Juvenile Paddlefish in a Mainstem Missouri River Reservoir

ABSTRACT Hatchery-raised paddlefish (Polyodon spathula) were implanted with ultrasonic transmitters and tracked from August to November 1998 and March to November of 1999 and 2000 to determine diel movements and seasonal distribution in Lake Francis Case. South Dakota. Juvenile (340 to 432 mm eye to fork length) paddlefish (N=32) exhibited variable movement patterns but remained in the upper reservoir reaches throughout the three-year study. Movement rates ranged hm 35 to 3,464 m/h with 90% of all locations in the upper third (51 kml of the reservoir. Increased movement rates were weakly correlated with increased water temperature (r=0.16, P=0.04). Daytime paddlefish movement peaked in July and August. However, diel movements were variable among seasons. In spring, movement rates did not differ among diel periods, whereas summer movements were lower during crepuscular periods and fall movements were lowest during the day. Although paddlefish were stocked at two locations in Lake Francis Case, they appeared to disperse and use reservoir areas similarly.

Ultrasonic diagnostic imaging system transmitter for sum and difference frequency imaging

An ultrasonic diagnostic imaging system is described for performing nonlinear echo signal imaging with intermodulation product (sum or difference frequency) components. The system includes a digital transmitter which develops digital waveforms for two frequencies of a transmit beam. The digital waveforms are combined, converted to analog waveforms, and applied as transmit signals to the elements of a transducer array. In an alternate embodiment, a library of digital, multifrequency waveforms is maintained, from which a desired digital waveform is selected, converted to an analog waveform, and applied as transmit signals to the elements of a transducer array.

Diel activity of Sarpa salpa (Sparidae) by ultrasonic telemetry in a Posidonia oceanica meadow of Corsica (Mediterranean Sea)

In the Mediterranean Sea, the fish Sarpa salpa (Sparidae) is the only vertebrate grazer of Posidonia oceanica meadows. In order to gain knowledge about the behaviour of S. salpa and a better understanding of the meadow's primary production recycling, an original study was designed using ultrasonic telemetry to investigate activity patterns and space utilisation in the field. During June–September 2000, we compared diel movements of six adult S. salpa (249–317 mm FL and 313–633 g) in the Bay of Calvi. These fish were tagged by intraperitoneal insertion of ultrasonic transmitters. Their positions were recorded with a directional hydrophone from a small boat with an accuracy between 10 and 50 m, depending on the local environment. The tracking duration ranged from 3 to 22 days (average 11.8 ± 7.3). Locations were performed from at least dawn to dusk or early night, and one fish was tracked during the entire 24-h cycle. Fish were more mobile during the twilight periods, but statistical analysis indicated individual differences for the precise period of mobility. Two major behavioural patterns were observed: first, the fish remained in close vicinity of the harbour during the day and moved away to the north or the south at dusk to access nocturnal sites, occupying a home range of about 4.3 ha. The second behavioural pattern involved persistent occupation of the same sites during day and night within a relatively restricted home range (about 0.8 ha). Great variation in mobility was found and the same individual fish could show both kinds of behaviour.

Habitat selection by juvenile European sturgeon Acipenser sturio in the Gironde estuary (France)

Journal of Applied IchthyologyVolume 18, Issue 4-6 p. 536-541 Habitat selection by juvenile European sturgeon Acipenser sturio in the Gironde estuary (France) C. Taverny, C. Taverny Unité de Recherche Ressources Aquatiques Continentales, Cemagref, Cestas, France; Association Girondine pour l'Expérimentation et le Développement des Ressources Aquatiques, Saint André de Cubzac, France; Faune et Parcs du Québec, Montreal, Quebec, CanadaSearch for more papers by this authorM. Lepage, M. Lepage Unité de Recherche Ressources Aquatiques Continentales, Cemagref, Cestas, France; Association Girondine pour l'Expérimentation et le Développement des Ressources Aquatiques, Saint André de Cubzac, France; Faune et Parcs du Québec, Montreal, Quebec, CanadaSearch for more papers by this authorS. Piefort, S. Piefort Unité de Recherche Ressources Aquatiques Continentales, Cemagref, Cestas, France; Association Girondine pour l'Expérimentation et le Développement des Ressources Aquatiques, Saint André de Cubzac, France; Faune et Parcs du Québec, Montreal, Quebec, CanadaSearch for more papers by this authorP. Dumont, P. Dumont Unité de Recherche Ressources Aquatiques Continentales, Cemagref, Cestas, France; Association Girondine pour l'Expérimentation et le Développement des Ressources Aquatiques, Saint André de Cubzac, France; Faune et Parcs du Québec, Montreal, Quebec, CanadaSearch for more papers by this authorE. Rochard, E. Rochard Unité de Recherche Ressources Aquatiques Continentales, Cemagref, Cestas, France; Association Girondine pour l'Expérimentation et le Développement des Ressources Aquatiques, Saint André de Cubzac, France; Faune et Parcs du Québec, Montreal, Quebec, CanadaSearch for more papers by this author C. Taverny, C. Taverny Unité de Recherche Ressources Aquatiques Continentales, Cemagref, Cestas, France; Association Girondine pour l'Expérimentation et le Développement des Ressources Aquatiques, Saint André de Cubzac, France; Faune et Parcs du Québec, Montreal, Quebec, CanadaSearch for more papers by this authorM. Lepage, M. Lepage Unité de Recherche Ressources Aquatiques Continentales, Cemagref, Cestas, France; Association Girondine pour l'Expérimentation et le Développement des Ressources Aquatiques, Saint André de Cubzac, France; Faune et Parcs du Québec, Montreal, Quebec, CanadaSearch for more papers by this authorS. Piefort, S. Piefort Unité de Recherche Ressources Aquatiques Continentales, Cemagref, Cestas, France; Association Girondine pour l'Expérimentation et le Développement des Ressources Aquatiques, Saint André de Cubzac, France; Faune et Parcs du Québec, Montreal, Quebec, CanadaSearch for more papers by this authorP. Dumont, P. Dumont Unité de Recherche Ressources Aquatiques Continentales, Cemagref, Cestas, France; Association Girondine pour l'Expérimentation et le Développement des Ressources Aquatiques, Saint André de Cubzac, France; Faune et Parcs du Québec, Montreal, Quebec, CanadaSearch for more papers by this authorE. Rochard, E. Rochard Unité de Recherche Ressources Aquatiques Continentales, Cemagref, Cestas, France; Association Girondine pour l'Expérimentation et le Développement des Ressources Aquatiques, Saint André de Cubzac, France; Faune et Parcs du Québec, Montreal, Quebec, CanadaSearch for more papers by this author First published: 17 December 2002 https://doi.org/10.1046/j.1439-0426.2002.00414.xCitations: 28AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume18, Issue4-6December 2002Pages 536-541 RelatedInformation

Evidence of homing of black rockfish Sebastes inermis using biotelemetry

The black rockfish Sebastes inermis is one of the most important fishery species along the coast from southern Hokkaido to Kyushu, Japan and is often found in rocks and Zostera areas. We conducted biotelemetry using coded ultrasonic transmitters to clarify the movement of the black rockfish that inhabited the seawall of the Kansai International Airport. We released 25 black rockfish at two points. One was the airport seawall and the other was side shallows off the Sensyu district. Seventeen black rockfish returned to their capture site after release. We used the V-test to determine whether the direction of movement was random or orientated. The black rockfish moved at random along the seawall within some hours after release (P>0.05). Four hours after release, they moved to their home site intentionally (P<0.0025).

Residence of fish in the vicinity of a decommissioned oil platform in the North Sea

Jorgensen, T., Lokkeborg, S., and Soldal, A. V. 2002. Residence of fish in the vicinityof a decommissioned oil platform in the North Sea. – ICES Journal of Marine Science,59: S288–S293.The suggested use of decommissioned oil platforms as artificial reefs initiated a study ofthe abundance and residence of fish in the vicinity of the Albuskjell 2/4 Fox platform in theNorwegian sector of the North Sea. A study of fish residence was carried out by means ofcylindrical coded ultrasonic VEMCO transmitters surgically implanted into the abdominalcavity of fish caught by handline and pots near the platform. After the operation, the fishwere kept in a tank of running seawater to ensure that only fully recovered fish werereleased. Twenty-nine cod and two haddock were tagged. Eight ultrasonic receiversanchored around the platform recorded the presence of tagged fish. An additional receiverwas placed at a neighbouring platform 8 km away. Data were collected from 25 May to13 August 1998 and showed that approximately 50% of the tagged fish remained at ornear the platform throughout this period. Four tagged cod were registered by the receiverat the neighbouring platform. Five tagged cod have been reported caught, one at thestudy platform, two at a nearby platform, and two at 9 and 150 km distance, respectively.When the platform was revisited in May 1999 four cod were detected.

Movements of Displaced Largemouth Bass in Two Indiana Natural Lakes

ABSTRACT Movements of largemouth bass Micropterus salmoides that were displaced within and between two inter-connected natural lakes in Indiana were monitored to determine if they would return to their capture locations. Nine largemouth bass were captured by angling and electro fishing at Lake Wawasee and surgically fitted with ultrasonic transmitters. Five bass (experimentals) were then displaced 3.1–8.1 km downstream into Syracuse Lake. For comparison, four bass (controls) were released in Lake Wawasee, two displaced (2.4 and 3.6 km) and two released at their capture sites. Locations of bass were determined over a 15-month period. Only one experimental bass returned to Lake Wawasee and the area where it was captured. One experimental bass was removed from the channel between the lakes by an angler, another bass failed to return and either died or shed its transmitter in Syracuse Lake, and two experimental bass were last located within Syracuse Lake before contact was lost. The two control bass displaced within Lake Wawasee returned to their capture areas, while the two control bass released at their capture sites remained in those vicinities and moved shorter distances than displaced fish. Experimental fish were tracked during 11–348 d, compared to 77–452 d for control fish, possibly reflecting greater survival of the latter. The results of this study should encourage largemouth bass tournament organizers and fishery managers to adopt measures to reduce inter-lake displacement of angler-caught fish.

Effects of capture and transmitter attachments on the swimming speed of large juvenile lemon sharks in the wild

The swimming speed of seven large juvenile lemon sharks Negaprion brevirostris following attachment of an external speed‐sensing ultrasonic transmitter was significantly higher during the first 18 h after release compared to the average swimming speed obtained &gt;48 h after release. The external speed‐sensing transmitter can be used to monitor the voluntary swimming speed of large fishes in the field, but data during the first 24 h period should be excluded from analysis of natural speeds, at least from species similar in behaviour to N. brevirostris.

Attachment, validation, and preliminary deployment of ultrasonic heart rate transmitters on largemouth bass, Micropterus salmoides

Although there are numerous published accounts of studies utilizing heart rate ( fH) transmitters in fish, few of these studies provide sufficient detail to aid other researchers in deploying these devices. Here, we detail the attachment, validation, and preliminary deployment of a commercially available ultrasonic fH transmitter. We used largemouth bass, Micropterus salmoides, for this study because they principally modulate cardiac output using fH, making them logical candidates for this technology. Using an external harness that balanced the battery on one side of the dorsum, and the transmitter on the other, we attached the device to 13 fish. Electrodes were positioned ventral-laterally to the pericardial cavity. Doppler flow probes were used to validate that the transmitter was detecting and emitting a signal when triggered by the depolarization of the ventricle (QRS wave), as indicated by peaks in blood flow. We then deployed the fH transmitters for periods of up to 32 days, generating one of the most complete series of fH data available. We present preliminary data illustrating the information available from fH transmitters at different temporal resolutions (real time vs. hourly means), including relationship of fH to temperature, behavioral correlates of fH, and diel patterns of fH.

MIGRATORY PATTERNS OF FEMALE SPIDER CRABS MAJA SQUINADO DETECTED USING ELECTRONIC TAGS AND TELEMETRY

Abstract Migrations play a key role in the life history of the spider crab Maja squinado (Herbst, 1788) and affect fishery catches. Migrations involve important changes in depth and in the environment. Ultrasonic telemetry has a number of drawbacks due to the difficulties in the continuous tracking of crabs while they are moving to deep waters. The recent introduction of electronic data storage or archival tags permits continuous monitoring of depth and temperature in crab's habitat and reconstruction of the movement patterns using baseline data on habitat characteristics. On the Galician coast (NW Spain) we calibrated and used electronic tags as a tool to study spider crab migrations. In the summer of 1996, 17 crabs were tagged with both ultrasonic transmitters and electronic tags. Tracking was carried out discontinuously at intervals of approximately 1 wk. We obtained a recapture rate of approximately 70%. The information provided by telemetry and electronic tags indicates autumn migrations along the ba...