scholarly journals Design of an underwater acoustic array for full ocean depth multi-beam echo sounder

2019 ◽  
Vol 283 ◽  
pp. 05002
Author(s):  
Haoqi Hao ◽  
Tiejian Xia ◽  
Min Xie
Keyword(s):  
High Reliability ◽  
Integrated Design ◽  
High Sensitivity ◽  
Underwater Acoustic ◽  
Technical Requirements ◽  
Planar Array ◽  
In Series ◽  
Stable Performance ◽  
Acoustic Array ◽  
Echo Sounder

In order to meet the technical requirements of full ocean depth multibeam echo sounder, the underwater acoustic array must have the ability of wide coverage, broadband response, high sensitivity and high reliability. This paper presents a design of underwater acoustic array based on Mills cross configuration with separate transmitting and receiving units. The arrays have modules design, hence the beamwidth of the array can be adjusted according to particular installation requirements. The working frequency band of the arrays is between 10.5kHz to 13.5kHz, and the coverage angle can cover -71.6°~71.6°. The Integrated design is used to achieve a wide-angle beam coverage of the planar array, which combines the transducer and the sound baffle together to realize a wide directivity of the array elements. The longitudinal bending transducers are designed to meet the broadband requirements for the transmitting array, which are Tonpilz transducers with flexural radiating head. On the other hand, each element of the receiving array is composed of several hydrophones, which are connected in series to achieve high sensitivity. The double-layer watertight technology is also applied in our design, ensuring stable performance and long service life.

scholarly journals A Full-Range Flexible and Printed Humidity Sensor Based on a Solution-Processed P(VDF-TrFE)/Graphene-Flower Composite

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1915
Author(s):  
Shenawar Ali Khan ◽  
Muhammad Saqib ◽  
Muhammad Muqeet Rehman ◽  
Hafiz Mohammad Mutee Ur Rehman ◽  
Sheik Abdur Rahman ◽  
...  
Keyword(s):  
Active Layer ◽  
Humidity Sensor ◽  
High Reliability ◽  
Full Range ◽  
High Sensitivity ◽  
Fast Response ◽  
Considerable Change ◽  
Relative Humidity Range ◽  
Response And Recovery ◽  
Proportional Relationship

A novel composite based on a polymer (P(VDF-TrFE)) and a two-dimensional material (graphene flower) was proposed as the active layer of an interdigitated electrode (IDEs) based humidity sensor. Silver (Ag) IDEs were screen printed on a flexible polyethylene terephthalate (PET) substrate followed by spin coating the active layer of P(VDF-TrFE)/graphene flower on its surface. It was observed that this sensor responds to a wide relative humidity range (RH%) of 8–98% with a fast response and recovery time of 0.8 s and 2.5 s for the capacitance, respectively. The fabricated sensor displayed an inversely proportional response between capacitance and RH%, while a directly proportional relationship was observed between its impedance and RH%. P(VDF-TrFE)/graphene flower-based flexible humidity sensor exhibited high sensitivity with an average change of capacitance as 0.0558 pF/RH%. Stability of obtained results was monitored for two weeks without any considerable change in the original values, signifying its high reliability. Various chemical, morphological, and electrical characterizations were performed to comprehensively study the humidity-sensing behavior of this advanced composite. The fabricated sensor was successfully used for the applications of health monitoring and measuring the water content in the environment.

Pitch and Depth Keeping of Moored-type Underwater Acoustic Array System

2019 ◽  
Author(s):  
Suk-Min Yoon ◽  
Chong-Moo Lee ◽  
Kihun Kim ◽  
Sung-Hoon Byun
Keyword(s):  
Underwater Acoustic ◽  
Acoustic Array

The Design of Dual-Mode Traffic Lights Control System Based on FPGA

2013 ◽  
Vol 341-342 ◽  
pp. 732-736
Author(s):  
Yan Yan Yu ◽  
Ya Qun Huang ◽  
Lei Wang ◽  
Fu Shou Tao
Keyword(s):  
Control System ◽  
Traffic Management ◽  
High Reliability ◽  
Single Chip ◽  
Dual Mode ◽  
Traffic Scheduling ◽  
Development Environment ◽  
Traffic Lights ◽  
Road Intersections ◽  
Stable Performance

The traffic signal lights control system automatically controls the statues of the intersection traffic lights and dispatch the traffic vehicles normally that traffic scheduling is an important system and it is the most basic and most important tools in city traffic management. Traffic lights control system made by single chip microcomputer technology has a single working model, low reliability, slow speed, and it can't modify or upgrade online, which is difficult to adapt to changes at different times of the traffic flow. This design of the dual mode of traffic lights control system intelligently controls each intersection traffic lights on and off time in the different period, which will improve the scheduling efficiency of road intersections. The design is based on FPGA with a digital display of traffic lights control system, compile the program design and simulation in Quartus II development environment, and ultimately download to EP2C35F672C6 chip of Altera Company. By the DE2 experiments test platform, the system has stable performance, simple operation, easy to maintenance, high reliability, strong expansibility and good refactoring.

A comparison of bronchofiberscopic (BFS) washing cytology (BWC) and formalin-fixed paraffin-embedded tissue (PPFE) in the analysis of EGFR mutations in advanced non-small cell lung cancer (NSCLC).

2013 ◽  
Vol 31 (15_suppl) ◽  
pp. 8054-8054
Author(s):  
Naoya Hida ◽  
Yuuki Misumi ◽  
Yoko Agemi ◽  
Akira Sato ◽  
Mari Ishii ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Egfr Mutation ◽  
High Reliability ◽  
High Sensitivity ◽  
Mutation Testing ◽  
Egfr Mutations ◽  
Mutation Site ◽  
Mutation Status ◽  
Bronchial Washing ◽  
Egfr Mutation Testing

8054 Background: In the treatment of advanced NSCLC, EGFR mutation status is one of the most predictive factors for the efficacy of EGFR tyrosine kinase inhibitors, and the evaluation of EGFR mutation status using the PPFE has been widely used for this analysis throughout the world. However, whether BWC can be used as an alternative for PPFE in the analysis of EGFR mutations is unknown. The largest study evaluating these 2 methods included only around 20 samples. Therefore, in the current study, we compared the freeze stock solution of BWC with PPFE for the determination of EGFR mutation status in a large sample set. Methods: In diagnostic BFS examinations, after curetting or brushing and biopsy to target lesions, subsequent bronchial washing by saline was performed. Thereafter, the saline fluid in which the forceps were washed and the bronchial washing fluid were mixed in a sterilized tube and were immediately frozen in a -20°C freezer. EGFR mutation testing for both BWC and PPFE was performed using high-sensitivity PCR (BML, PCR-Invader). Results: A total of 440 BFS examinations were performed from Aug 2010 to Nov 2011 in our hospital. The BWCs of 268 suspected cases of lung cancer were successfully obtained. Of these, 51 cases that were pathologically confirmed as adenocarcinoma based on both BWC and PPFE were analyzed in this study. EGFR mutations were identified in 25 cases, while the remaining 26 cases had wild-type EGFR. In 49 of 51 cases, the results of EGFR mutation status were the same for BWC and PPFE, and the concordance rate was 96%. In one case, an exon-18 mutation was detected only by BWC. In another case an exon-21 mutation was detected only by PPFE. In 24 of 25 cases of EGFR mutation, the mutation site was the same in both samples. The kappa coefficient was 0.92. Conclusions: This is the largest genetic study to date demonstrating a head-to-head comparison of BWC and PPFE for the evaluation of EGFR mutations. Both methods showed high reliability and concordance using high-sensitivity PCR. BWC is considered a simple, rapid method and represents an effective alternative for PPFE in EGFR mutation testing.

Novel on-tap passive sampling for odorous compounds in drinking water

2008 ◽  
Vol 8 (2) ◽  
pp. 197-205
Author(s):  
Christophe Tondelier ◽  
David Benanou ◽  
Thomas Thouvenot ◽  
Arnaud Genin
Keyword(s):  
Drinking Water ◽  
Passive Sampling ◽  
Water Flow Rate ◽  
Internal Standard ◽  
High Sensitivity ◽  
Qualitative Aspect ◽  
Mixing Chamber ◽  
In Series ◽  
Loading And Unloading ◽  
Private Network

Because taste and odour events in drinking water are often fleeting and unpredictable phenomena, an innovating passive sampler has been developed to trap off-flavour compounds, directly at the tap of the consumer: ARISTOT (Advanced Relevant Investigation Sampler for Taste & Odour at Tap). Each tool is equipped with seven SBSE stir bars, magnetic stirring roads coated with a polydimethylsiloxane (PDMS) phase, allowing the sorption of water organic compounds into PDMS at each tap opening. To study the efficiency of these passives samplers, a private network pilot unit has been created in our laboratory, equipped with four faucets in series, solenoids valves for automation of the system and a mixing chamber, developed to spike drinking water with odourous compounds in order to have homogenous smelling water at each tap. After enrichment, the bars are taken out and are then in-line thermo-desorbed and analysed by gas chromatography coupled with a mass spectrometer. Results showed a high sensitivity of the system, which was able to quickly analyse odourous compounds at the sub ng/L level. A “multishot” method was developed to analyse every molecule trapped on the seven stir bars in only one chromatographic run increasing sensitivity. To follow enrichment of stir bars, loading and unloading were studied and showed a very slight unloading of the stir bar under a clean water flow rate which allowed us to previously spike every stir bar with an internal standard to see analytical variations. The influence of heated water was also investigated and seems to lead to a higher unloading of the stir bar, but according to a qualitative aspect this loss is balanced by the high sensitivity.

The Application of RAKE Receiving Technology in the Underwater SS Communication

2014 ◽  
Vol 513-517 ◽  
pp. 4248-4252 ◽  
Author(s):  
Yun Hang Zhu ◽  
Zhi Hui Deng
Keyword(s):  
High Speed ◽  
Simulation Analysis ◽  
High Reliability ◽  
Underwater Acoustic Communication ◽  
Technical Solution ◽  
Acoustic Transmission ◽  
Long Distance ◽  
Underwater Acoustic ◽  
Underwater Wireless Communication ◽  
Spreading Spectrum

In recent years, the strategic significance of the oceans is growing as well as its research and development needs. The underwater wireless communication is becoming more and more important. The underwater acoustic communication is one of the few mediums which can conduct the underwater transmission over a long distance, and the multipath effect is the major obstacle of affecting the systems high speed and high reliability. The characteristics of underwater acoustic fading and coherent multi-path channel are studied, and the model of underwater acoustic spreading spectrum (SS) communication system is established. The affect of coding technique on the systems performance are analyzed in detail. The improved RAKE receiving technical solution is put forward, whose simulation analysis and data in different combining ways are given. It is proved that the scheme can better solve the problem of multipath interference in underwater acoustic transmission.

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