788 research outputs found

    Reducing Theft of Oysters Through the Use of RFID Technology

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    Poaching (theft) of oyster from the oyster beds is a huge problem. Purpose of this study is to assess a means of reducing poaching. The means to be studied is the use of RFID (Radio Frequency Identification) tags to mark oysters that would be placed on the beds so that when oysters from those beds are brought to the seafood processor, their origin can be identified. A detailed discussion of RFID appears in a later section of this study. RFID tags are to be put in dummy oysters, which should be hard to detect from real oysters. The shells must have a suitable media to hold the shell together and give it about the same density as a live oyster. Further, as detailed later, the media should be an electrically insulating material so that it does not absorb electromagnetic radiation

    Underwater Inductive Power Transfer with Wireless Charging Applications

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    Underwater wireless power transfer (UWPT) has become an area of great interest due to the advancement of autonomous underwater vehicles (AUVs) and electic boats. This paper seeks to investigate the variation of the coupling coefficient and power transfer in air versus in seawater. The design is based on a class E converter as it can achieve soft-switching inherently. I made the transmitter and receiver coils then measured self-inductance and parasitic resistance in air and in water. I noted that self-inductance increases when they are placed in water but the mutual inductance is lower. I then calculated the component values for the class E converter based on inductor values (140 ÎĽH and 105 ÎĽH) and simulated the circuit on LTspice. The power at the output was 74W which is lower than the required value. However, I noted that reducing the coils inductance values while maintaining the value of the other passive components increased the efficiency and power at the output upto four times (311W). The final value chosen for making the inductors was 115 ÎĽH and 75 ÎĽH as these values gave the maximum power at the output while achieving ZVS. I then designed the transmitter and receiver circuits on Altium and printed the PCBs. All the components were then soldered onto the board and the tests done

    Sensor monitoring strategy

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    In its overall strategy, COMMON SENSE work packages (11) can be grouped into 3 key phases: (1) RD basis for cost-effective sensor development, (2) Sensor development, sensor web platform and integration, and (3) Field testing. In the Phase 1, within WP1 and WP2, partners have provided a general understanding and integrated basis for a cost effective sensors development. In Phase 2, within the WP3 and WPs 4 to 8, the new sensors have been created and planned to be integrated into instruments for the different identified platforms and how data produced will be processed, organised and saved. During the phase 3, within WP9, partners are deploying precompetitive prototypes at chosen platforms (e.g. research vessels, oil platforms, buoys and submerged moorings, ocean racing yachts, drifting buoys). Starting from August 2015 (month 22; Task 9.2), these platforms are permitting the partnership to test the adaptability and performance of the in-situ sensors and verify if the transmission of data is properly made and correct observed deviations. Sensor monitoring strategy (Deliverable 2.4 for Task 2.5) is the last task within Phase 1. As the other tasks in Phase 1 it has to provide a basis for designing field testing activities to be useful. That is how to validate the performance of sensors, integration, data acquisition, transmission, under real conditions in different platforms. Since there is a wide sensor variety, each one with its own characteristics, and several platforms, to prepare a general methodological review and give the corresponding directions as it was initially planned, would be a huge and useless effort. Given the initially fixed calendar a first version of the present deliverable was presented when most of the sensors were still not developed. The document addressed how projected sensors should be tested, their limitations and conditions for their monitoring and final certification. Now, when D2.2 (Procedures of sensors deployment methodology on physical supports/platforms) has been rewritten (May 2016), all sensors are fully developed and most of them have started their tests at sea, the present new updated version of the deliverable becomes more precise, with much better knowledge on the real sensors and their performance. In addition, a complete new chapter on data transmission –initially proposed but not developed in the previous version– is included. The information from the six sensor developers in COMMON SENSE on which the initial plan on where and how to test each sensor that was presented in D9.1 (April 2015) has been updated (May 2016). The update includes the final properties of sensors after the respective full laboratory tests and even some of the results from field tests that had been carried out starting August 2015. This task assesses field testing procedures and deployment specificities. Two tables are presented based on the information of the report for D9.1 delivered in April 2015. One table was created for sensor developers and one for those who will test the sensors at sea. In this report some information from the testers’ table is shown and updated according to the new version of D2.2 (May 2016) for platforms. Objectives and rationale The objective of Task 2.5 within the WP2 is the definition of sensor monitoring strategy based on the premises for water monitoring, sensor performances and data storage and transmission. For any new sensor, available instruments currently used in the oceanographic studies will be identified to perform comparisons. Suitable transmission technology will be selected according to the test conditions: open sea, coastal areas, remote locations, etc. Sensitivity and stress tests will be designed in order to establish confidence limits under different environmental situations, so that the results obtained in the testing exercises (WP9) will enable to certify the performance of the new instruments

    Characterization of RF signals in Different Types of Water

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    Underwater communication at microwave frequencies overcome the data rate and bandwidth limitations of acoustic communication and the environmental problems associated with optical-based underwater networks. It has several applications in underwater sensors networks. In view of potential applications to 5G, we conducted experimental tests and computer simulations to investigate the propagation losses encountered by microwave signals in the licensed and license-free frequencies (up to 2.6 GHz) in freshwater and seawater. Our results indicate the feasibility of microwave communication in freshwater at the licensed mobile frequencies

    Fiber Optic Technology: It’s Role in Information Revolution

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    Everywhere on this planet, hair-thin optical fibers carry vast quantities of information from place to place. There are many desirable properties of optical fibers for carrying this information. They have enormous information-carrying capacity, are low cost, and possess immunity from the many disturbances that can afflict electrical wires and wireless communication links. The superiority of optical fibers for carrying information from places to place is leading to their rapidly replacing older technologies. Optical fibers have played a key role in making possible the extraordinary growth in world-wide communications that has occurred in the last 25 years, and are vital in enabling the proliferating use of the Internet. Keywords: Fiber optics, refractive index, claddings, attenuation, repeaters, dispersion, encoding, fiber network, architecture
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