Ocean noise level change in response to ocean acidification.

2009 ◽  
Vol 126 (4) ◽  
pp. 2211
Author(s):  
Ilya A. Udovydchenkov ◽  
Timothy F. Duda
Keyword(s):  
Ocean Acidification ◽  
Noise Level ◽  
Level Change ◽  
Ocean Noise

Experimental Study on Durability and NVH of Rear Driving Axle of Minibus

2013 ◽  
Vol 655-657 ◽  
pp. 511-514
Author(s):  
Hui Bin Li ◽  
Awais A.M. ◽  
Qi Chen Lu ◽  
De Quan Jin
Keyword(s):  
Experimental Study ◽  
Time Domain ◽  
Noise Level ◽  
The Other ◽  
Vibration Level ◽  
Bench Tests ◽  
Level Change ◽  
Frequency Domain Methods ◽  
Frequency Components ◽  
The One

Experiments on the durability for the rear driving axle were conducted in bench tests. By using time domain and frequency domain methods, the vibration and noise signals at bearings of driving axle were sampled and then analyzed. On the one hand, we find that the vibration level and noise level change with the wear of gears and bearings. On the other hand, with the development of the wear of gear and bearings, the frequency components of vibration and noise change with time. These experimental results will give help to further study of the durability and NVH characteristic of the rear driving axle.

Underwater Intrusion Surveillance System Based on Underwater Sensor Networks: Architecture, System Design and Research Challenge

2011 ◽  
Vol 201-203 ◽  
pp. 2053-2057
Author(s):  
Jun Jie Zheng ◽  
Zhi Hua Liu ◽  
Lu Yin ◽  
Song Ye ◽  
Yang Wang
Keyword(s):  
Sensor Networks ◽  
System Design ◽  
Noise Level ◽  
Surveillance System ◽  
Underwater Sensor Networks ◽  
Ocean Noise ◽  
Research Challenge

Submarine is a kind of effective underwater weapon and with the development of technology,the noise level is almost equal to ambient ocean noise and making them difficult to be detected by sonar.In this paper,the shortcomings of existing architecture for underwater sensor networks are analyzed and a new architecture for underwater intrusion surveillance based on underwater sensor networks is designed and the research challenge is introduced.

5. How to kill nearly everything

2019 ◽  
pp. 76-95
Author(s):  
Paul B. Wignall
Keyword(s):  
Ocean Acidification ◽  
Sea Level ◽  
Ozone Depletion ◽  
Sea Level Change ◽  
Mass Extinctions ◽  
Meteorite Impact ◽  
Large Igneous Provinces ◽  
Level Change ◽  
Igneous Provinces ◽  
Ultimate Cause

‘How to kill nearly everything’ considers the proposed causes of mass extinctions, often called the kill mechanisms. An almost bewildering array of ideas have been put forward as likely bringers of death, but most of the debates have concentrated on just a few culprits, notably volcanism and meteorite impact, because their timing is closely coincidental with the extinctions. However, it is important to note that while they may be the ultimate cause of a crisis, it is their consequences that likely lead to proximate (or direct) causes of extinction. The main causes discussed are large igneous provinces, hyperthermals, ocean anoxia, ocean acidification, ozone depletion, ice ages, sea-level change, and meteorite and comet impacts.

Electron Microscopy in Molecular Biology

1967 ◽  
Vol 25 ◽  
pp. 2-3
Author(s):  
Cecil E. Hall
Keyword(s):  
Electron Microscopy ◽  
Molecular Biology ◽  
Noise Level ◽  
Molecular Structures ◽  
Material Structure ◽  
The Arts ◽  
Shadow Casting ◽  
Electron Image ◽  
High Degree ◽  
Very High

The visualization of organic macromolecules such as proteins, nucleic acids, viruses and virus components has reached its high degree of effectiveness owing to refinements and reliability of instruments and to the invention of methods for enhancing the structure of these materials within the electron image. The latter techniques have been most important because what can be seen depends upon the molecular and atomic character of the object as modified which is rarely evident in the pristine material. Structure may thus be displayed by the arts of positive and negative staining, shadow casting, replication and other techniques. Enhancement of contrast, which delineates bounds of isolated macromolecules has been effected progressively over the years as illustrated in Figs. 1, 2, 3 and 4 by these methods. We now look to the future wondering what other visions are waiting to be seen. The instrument designers will need to exact from the arts of fabrication the performance that theory has prescribed as well as methods for phase and interference contrast with explorations of the potentialities of very high and very low voltages. Chemistry must play an increasingly important part in future progress by providing specific stain molecules of high visibility, substrates of vanishing “noise” level and means for preservation of molecular structures that usually exist in a solvated condition.

Detection of a point defect in a silicon single crystal by high-resolution TEM

1995 ◽  
Vol 53 ◽  
pp. 466-467
Author(s):  
M. Awaji
Keyword(s):  
High Resolution ◽  
Single Crystal ◽  
Point Defect ◽  
Point Defects ◽  
Noise Level ◽  
Dark Field ◽  
Silicon Single Crystal ◽  
High Resolution Image ◽  
Dark Field Imaging ◽  
Field Imaging

It is necessary to improve the resolution, brightness and signal-to-noise ratio(s/n) for the detection and identification of point defects in crystals. In order to observe point defects, multi-beam dark-field imaging is one of the useful methods. Though this method can improve resolution and brightness compared with dark-field imaging by diffuse scattering, the problem of s/n still exists. In order to improve the exposure time due to the low intensity of the dark-field image and the low resolution, we discuss in this paper the bright-field high-resolution image and the corresponding subtracted image with reference to a changing noise level, and examine the possibility for in-situ observation, identification and detection of the movement of a point defect produced in the early stage of damage process by high energy electron bombardment.The high-resolution image contrast of a silicon single crystal in the [10] orientation containing a triple divacancy cluster is calculated using the Cowley-Moodie dynamical theory and for a changing gaussian noise level. This divacancy model was deduced from experimental results obtained by electron spin resonance. The calculation condition was for the lMeV Berkeley ARM operated at 800KeV.

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