scholarly journals Array MEMS Vector Hydrophone Oriented at Different Direction Angles

Sensors ◽  
2019 ◽  
Vol 19 (19) ◽  
pp. 4282 ◽  
Author(s):  
Mengran Liu ◽  
Lei Nie ◽  
Shanqiang Li ◽  
Wen Jia ◽  
Lansheng Zhang ◽  
...  
Keyword(s):  
Sound Source ◽  
High Performance ◽  
Practical Significance ◽  
Wave Tube ◽  
Vector Hydrophone ◽  
Good Consistency ◽  
Mems Technology ◽  
New Type ◽  
Working Principle ◽  
Standing Wave Tube

A new type of array MEMS (Microelectro Mechanical Systems) vector hydrophone has been proposed to solve the left-right ambiguity problem that is commonly found in current ones. Meanwhile, the advantages of good sensitivity and low fabrication cost are maintained. The array MEMS vector hydrophone is integrated by four units oriented at different direction angles. By the aid of this kind of vector hydrophone, not only the exact direction of the sound source can be measured, but also the position obtained. The working principle of the array microstructure has been analyzed and simulated. The result shows that the position of the sound source can be well determined. The prototype of the hydrophone is fabricated based on standard MEMS technology, and its performance is tested in a standing wave tube and an anechoic tank. The testing results show that the array hydrophone exhibits a good consistency of all the four units and satisfactory performance. More importantly, this array hydrophone exhibits excellent ability of positioning with the relatively small angle error. Thus, a MEMS hydrophone with multiple functions and relatively high performance is realized, which has important theoretical and practical significance in relevant applications such as the small-size underwater vehicles.

Study of a Sound Absorbing Polyurethane Based on Porous Composite Material

2013 ◽  
Vol 275-277 ◽  
pp. 1623-1627 ◽  
Author(s):  
Xin Liang Zhang ◽  
Cun Ping Liu
Keyword(s):  
Sound Absorption ◽  
Glass Fibers ◽  
Low Frequency ◽  
Wave Tube ◽  
Porous Composite ◽  
Blowing Agent ◽  
Reduction Coefficient ◽  
Absorbing Material ◽  
New Type ◽  
Standing Wave Tube

A new type of sound absorbing material, which was made from super strength polyurethane and mass fiber, was investigated. And the sound absorption coefficient of the material was tested by standing wave tube method. Experiment results manifested that content of glass fibers, blowing agent and thickness have great effects on the sound absorbing performance of the sample. When the content of glass fiber and blowing agent are separately 3% and 0.4%, the performance of the material reaches optimum. The noise reduction coefficient of the material is 0.6, and the sound absorption property at middle-low frequency is good.

Preparation of a New Kind of Ultra-High Performance Water Reducer and its Application Study

2011 ◽  
Vol 250-253 ◽  
pp. 795-799 ◽  
Author(s):  
Guo Rong Duan ◽  
Xin Wang ◽  
Guo Hong Huang ◽  
Ying Gong
Keyword(s):  
High Performance ◽  
Raw Materials ◽  
High Water ◽  
Pollution Reduction ◽  
Practical Significance ◽  
Application Study ◽  
One Step ◽  
New Type ◽  
Maximum Water ◽  
First Time

For the first time, a new kind of polycarboxylic acid high-performance water reducer, with ultra-high water reducing performance, was prepared through one-step polymerization, using new type polyether TPEG and acrylic acid as raw materials. Maximum water-reducing ratio of TPC may reach 50%. The most distinguishing characteristic of TPC was its reaction character at normal temperatures (30°C), which was of great practical significance for energy conservation and pollution reduction.

A study on MEMS vector hydrophone and its orientation algorithm

Sensor Review ◽  
2020 ◽  
Vol 40 (2) ◽  
pp. 191-201
Author(s):  
Zhenzhen Shang ◽  
Wendong Zhang ◽  
Guojun Zhang ◽  
Xiaoyong Zhang ◽  
Lansheng Zhang ◽  
...  
Keyword(s):  
Standing Wave ◽  
Phase Error ◽  
Market Potential ◽  
Vibration Velocity ◽  
Wave Tube ◽  
Detection Mechanism ◽  
Content Type ◽  
Detection Systems ◽  
Vector Hydrophone ◽  
Standing Wave Tube

Purpose The problem of port and starboard ambiguity will exist when only utilize the vector or scalar parameters. Meanwhile, the amplitude-phase error between the vector and scalar can also cause this problem. In this paper, a compound MEMS vector hydrophone which contains cilia vector microstructure and piezoelectric ceramic tube has been presented to solve the problem. Compared with traditional MEMS vector hydrophone, the compound MEMS vector hydrophone can realize the measurement of sound pressure and vibration velocity simultaneously. Design/methodology/approach A compound MEMS vector hydrophone has been presented. The unipolar directivity of the combined signal which combine the acoustic pressure and vibration velocity is used to achieve the direction of arrival (DOA). This paper introduced the working principle and the target detection mechanism of the compound vector hydrophone. The amplitude and phase error are analyzed and corrected in the standing wave tube. After that, the authors use beam-forming algorithm to estimate the DOA. Findings The experimental results in the standing wave tube and the external field verified the vector hydrophone's directional accuracy up to 1 and 5 degrees, respectively. Practical implications The research of compound vector hydrophone plays an important role in marine acoustic exploration and engineering applications. Originality/value This research provides a basis for MEMS hydrophone directivity theory. The compound vector hydrophone has been applied in the underwater location, with a huge market potential in underwater detection systems.

scholarly journals Design and analysis of a new type and normally open hydraulic chuck

2020 ◽  
Vol 4 (1) ◽  
Author(s):  
Yanfu Li
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
High Performance ◽  
Structure Design ◽  
Clamping Force ◽  
Element Analysis ◽  
Drilling Rig ◽  
New Type ◽  
Working Principle ◽  
Overall Performance

To solve the problem that large torque drilling rig requires high performance of the chuck, this paper introduces the composition and working principle of a normally open hydraulic chuck, as well as the design and calculation method of its bearing capacity and clamping force. Through the use of creo2.0/simulate finite element analysis module, finite element analysis is made on the main structure parts of the chuck. The results show that the parameter selection and structure design of the chuck mechanism meet the requirements of use, which provides a guarantee for improving the reliability of the chuck mechanism and the overall performance of the drilling rig.

scholarly journals Ship Handling in Unprotected Waters: A Review of New Technologies in Escort Tugs to Improve Safety

2021 ◽  
Vol 2 (1) ◽  
pp. 46-62
Author(s):  
Santiago Iglesias-Baniela ◽  
Juan Vinagre-Ríos ◽  
José M. Pérez-Canosa
Keyword(s):  
High Performance ◽  
New Technologies ◽  
Weather Conditions ◽  
Hull Form ◽  
Best Available Technologies ◽  
Adverse Weather Conditions ◽  
Adverse Weather ◽  
New Type ◽  
Technological Challenge ◽  
And Performance

It is a well-known fact that the 1989 Exxon Valdez disaster caused the escort towing of laden tankers in many coastal areas of the world to become compulsory. In order to implement a new type of escort towing, specially designed to be employed in very adverse weather conditions, considerable changes in the hull form of escort tugs had to be made to improve their stability and performance. Since traditional winch and ropes technologies were only effective in calm waters, tugs had to be fitted with new devices. These improvements allowed the remodeled tugs to counterbalance the strong forces generated by the maneuvers in open waters. The aim of this paper is to perform a comprehensive literature review of the new high-performance automatic dynamic winches. Furthermore, a thorough analysis of the best available technologies regarding towline, essential to properly exploit the new winches, will be carried out. Through this review, the way in which the escort towing industry has faced this technological challenge is shown.

CAD AND CAE TECHNOLOGIES OF A NOVEL PLANE SIX-BAR SWAYING MACHINE

2008 ◽  
Vol 07 (01) ◽  
pp. 65-67
Author(s):  
CHANGPING ZOU ◽  
LI DU ◽  
XIANDE HUANG
Keyword(s):  
High Pressure ◽  
Kinetic Analysis ◽  
Rotational Speed ◽  
Preliminary Analysis ◽  
Unit Weight ◽  
The Novel ◽  
Parameterized Modeling ◽  
New Type ◽  
Working Principle ◽  
Key Dimensions

A new type of six-bar swaying machine was put forward, which is an ingenious combination of plane multi-bar mechanism and high pressure oil cylinder. Preliminary analysis shows that this machine has many advantages, such as the torque produced by its unit weight, its small size, its light deadweight, etc. Thus it can be applied to situations that need swaying mechanism with low rotational speed and great torque. Firstly, the mechanism composition and working principle of the swaying machine were introduced. Secondly, parameterized modeling of the mechanism was carried out by utilizing software ADAMS. Then kinematic analysis and kinetic analysis were completed by using ADAMS. Finally, key dimensions were adjusted according to kinetic analysis. These tasks are believed to be beneficial to the development of the novel transmission.

A Study on Process of Modular Li-Ion Power Batteries

2013 ◽  
Vol 273 ◽  
pp. 153-156
Author(s):  
Han Liang ◽  
Xiao Feng ◽  
Yuan An Li
Keyword(s):  
High Power ◽  
Internal Resistance ◽  
Power Battery ◽  
New Process ◽  
Good Consistency ◽  
New Type ◽  
Li Ion ◽  
Production Automation ◽  
The Way

Li-ion power battery which has a broad prospect of application in many industry fields is a new type of high power battery. The formation-testing and sorting-packing are necessary processes in battery manufacture. Currently the process of formation almost takes the way of monomer battery, then sorting and packing by measuring the parameters of its internal resistance, voltage and capacity. The operation is complicated and the amount of data is huge. On account of the problem, we propose a new process of battery modularization. It can greatly reduce the workload of the parameter testing when using the optimized process. And batteries can get a good consistency, which is favor of sorting-packing and production automation.

Famous teachers and educators of the first half of the XX century about the problems of the North Caucasian muslim education.

2021 ◽  
Vol 13 (2) ◽  
pp. 208-222
Author(s):  
Nadezhda O. Bleich ◽  
Keyword(s):  
Educational Process ◽  
Point Of View ◽  
Practical Significance ◽  
Past Century ◽  
North Caucasus ◽  
Caucasus Region ◽  
The Past ◽  
The North ◽  
New Type ◽  
Historical Heritage

The article is devoted to the consideration of the worldview positions of famous educators of the past century regarding the state of school education among Muslims of the North Caucasus region. It is proved that the enlighteners advocated the creation of a new type of national non-class school and the construction of the didactic foundations of the educational process in it. The novelty of the work is that, based on the analysis of the views of the advanced intelligentsia of the region, aimed at understanding the current socio-cultural situation, an attempt was made to scientifically understand the problems and prospects for the development of the Muslim educational system of the past from the point of view of the modern scientific paradigm. The practical significance of the publication lies in expanding the understanding of the system of Mohammedan education in the context of its historical heritage, which will help to comprehend modern problems associated with the reform of general and vocational education in the national Muslim republics.

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