Experimental results of the cooperative operation of autonomous surface vehicles navigating in complex marine environment

2021 ◽  
Vol 219 ◽  
pp. 108256
Author(s):  
M.A. Hinostroza ◽  
Haitong Xu ◽  
C. Guedes Soares
Keyword(s):  
Marine Environment ◽  
Experimental Results ◽  
Autonomous Surface Vehicles

Cooperative Path Following Ring-Networked Under-Actuated Autonomous Surface Vehicles: Algorithms and Experimental Results

2020 ◽  
Vol 50 (4) ◽  
pp. 1519-1529 ◽  
Author(s):  
Lu Liu ◽  
Dan Wang ◽  
Zhouhua Peng ◽  
Tieshan Li ◽  
C. L. Philip Chen
Keyword(s):  
Path Following ◽  
Experimental Results ◽  
Autonomous Surface Vehicles

Design of Monitoring System Used in Sink-Float Safety Device for Marine Engineering Equipment

2013 ◽  
Vol 475-476 ◽  
pp. 635-638
Author(s):  
Zi Yue Wu ◽  
Jie Qi ◽  
Chen Nan Xue
Keyword(s):  
Data Management ◽  
Monitoring System ◽  
Marine Environment ◽  
Experimental Results ◽  
Software Architectures ◽  
Safety Device ◽  
Engineering Equipment ◽  
The Core ◽  
Marine Engineering

A monitoring system used in marine sink-float safety device is introduced. The ARM Cortex-M3 is the core of microcontroller in this system, and the hardware and software architectures of the monitoring system are designed. The designed monitoring system can multi-point monitor marine environment around sink-float safety device, by doing this, the safety device can take marine equipment to escape from harsh marine environment by submerging a certain depth. So we can make sure marine equipment safe and normal. The experimental results show that the sink-float safety device can work normally in the harsh marine environment with the monitoring system. The acquisition of multi-point environment monitor as well as data management is achieved effectively. The reliability and safety of equipment are guaranteed by the sink-float safety device.

scholarly journals Study of Cadmium Bioaccumulation in Perna viridis through Food Pathway and Its Decontamination

2021 ◽  
Vol 4 (1) ◽  
pp. 17-22
Author(s):  
Octavin Exaudina ◽  
Wahyu Retno Prihatiningsih ◽  
Heny Suseno ◽  
Budiawan Budiawan
Keyword(s):  
Heavy Metals ◽  
Acetic Acid ◽  
Citric Acid ◽  
Marine Environment ◽  
Experimental Results ◽  
Perna Viridis ◽  
Cadmium Bioaccumulation

Seafood can be contaminated by heavy metals that contained in seawater and the source of food that marine biotas eats. Cadmium is one of the contaminants found in the marine environment. Bioaccumulation studies via foood pathway were complement previous studies through the seawater pathway. This study also made an effort to biologically decontaminate cadmium using acetic acid and citric acid. The experimental results showed the total bioaccumulation ability of Cd by Perna viridis was 74.01. Cd decontamination which accumulates in the Perna viridis decreases the level up to 21% 

Bioaccumulation of Zn and 137Cs in Glauconomya virens (Linnaeus, 176) Upon Exposure to Sigle and Mixture of Zn or 137Cs and Salinity

2021 ◽  
Vol 10 (2) ◽  
pp. 200-208
Author(s):  
B. Budiawan ◽  
H. Suseno ◽  
M. E. Puteri ◽  
W. R. Prihatiningsih ◽  
M. Makmur
Keyword(s):  
Marine Environment ◽  
Concentration Factor ◽  
Water Concentration ◽  
The Body ◽  
Experimental Results ◽  
137Cs Concentration ◽  
Elimination Process ◽  
Single Compartment ◽  
Two Parameters ◽  
Depuration Process

This study aims to determine the effect of concentrations and salinity of seawater on the bioaccumulation of zinc and cesium in the Glauconomya virens. Salinity conditions and contaminant concentrations in the marine environment can change due to weather and other inputs.  A biokinetic experiment was carried out using a single compartment approach that used radiotracer 65Zn and 137Cs.  The experiments conducted were biota collection, acclimatization, bioaccumulation, and elimination. Acclimatization aims for the adaptation of biota in an experimental environment. Bioaccumulation was by placing the biota in an aquarium containing seawater media spiked by  65Zn, Zn, and 137Cs radiotracer contaminants. The elimination process was the release of contaminants from the body of the biota by placing them in clean and flowing seawater. The experimental results show that the uptake and elimination of Zn and Cs were influenced by these two parameters (water concentration and salinity). The highest value of Concentration Factor (CF) for Zn was 11.14 ml.g-1 under influences its concentration of  0.7 ppm in water.  In the depuration process, Zn maintained by G virens were  39.44; 31.17; 23.62; and 23.92% after these organisms accumulate this element from seawater containing 0.1; 0.3, 0.5, and 0.7 ppm, respectively. The highest of 137Cs  under influences its concentration of 3 Bg.ml-1 reached 2.65 mL.g-1. The effect of salinity is directly proportional to the factor value of Zn and 137Cs concentration.

scholarly journals Identification Algorithm of Uncertain Sonar Signals in Complex Marine Environment

2017 ◽  
Vol 24 (s3) ◽  
pp. 235-242
Author(s):  
Xuefeng Zhang
Keyword(s):  
Feature Extraction ◽  
Digital Watermarking ◽  
Marine Environment ◽  
Recognition Performance ◽  
Digital Watermark ◽  
Experimental Results ◽  
Identification Algorithm ◽  
Pulse Waveform ◽  
Signal Source ◽  
Signal Parameters

Abstract The current identification algorithm using sonar signal parameters of bandwidth, frequency, duration and pulse waveform which are easy to detect and imitation, to identify the identity of sonar signal, resulting in part of the sonar signal identity is not easy to distinguish. Therefore, an algorithm based on signal feature extraction and digital watermarking is proposed to recognize the uncertain sonar signals. The algorithm embeds the digital watermark into the detection signal from the uncertain sonar. The identity of the signal is recognized by detecting whether the received signal contains watermarks. Experimental results showed that the proposed algorithm can effectively improve the recognition performance of sonar signal source.

Diagnostics of Gold Laser Plasmas

1988 ◽  
Vol 102 ◽  
pp. 357-360
Author(s):  
J.C. Gauthier ◽  
J.P. Geindre ◽  
P. Monier ◽  
C. Chenais-Popovics ◽  
N. Tragin ◽  
...  
Keyword(s):  
Experimental Results ◽  
Pure Gold ◽  
Electronic Temperature ◽  
X Ray ◽  
Laser Plasmas ◽  
Collisional Radiative Model ◽  
Radiative Model

AbstractIn order to achieve a nickel-like X ray laser scheme we need a tool to determine the parameters which characterise the high-Z plasma. The aim of this work is to study gold laser plasmas and to compare experimental results to a collisional-radiative model which describes nickel-like ions. The electronic temperature and density are measured by the emission of an aluminium tracer. They are compared to the predictions of the nickel-like model for pure gold. The results show that the density and temperature can be estimated in a pure gold plasma.

Observation of Phase Contrast Images in STEM and CTEM Modes by Using 100 kV Field Emission Electron Gun

1974 ◽  
Vol 32 ◽  
pp. 390-391
Author(s):  
Y. Harada ◽  
T. Goto ◽  
H. Koike ◽  
T. Someya
Keyword(s):  
Field Emission ◽  
Phase Contrast ◽  
Image Formation ◽  
Fresnel Diffraction ◽  
Experimental Results ◽  
Electron Gun ◽  
Scanning Microscopy ◽  
Emission Electron ◽  
Lattice Images

Since phase contrasts of STEM images, that is, Fresnel diffraction fringes or lattice images, manifest themselves in field emission scanning microscopy, the mechanism for image formation in the STEM mode has been investigated and compared with that in CTEM mode, resulting in the theory of reciprocity. It reveals that contrast in STEM images exhibits the same properties as contrast in CTEM images. However, it appears that the validity of the reciprocity theory, especially on the details of phase contrast, has not yet been fully proven by the experiments. In this work, we shall investigate the phase contrast images obtained in both the STEM and CTEM modes of a field emission microscope (100kV), and evaluate the validity of the reciprocity theory by comparing the experimental results.

A new dissociation mode for dislocations in silicon

1978 ◽  
Vol 36 (1) ◽  
pp. 346-347
Author(s):  
A. Ourmazd ◽  
G.R. Booker ◽  
C.J. Humphreys
Keyword(s):  
Detailed Examination ◽  
Experimental Results ◽  
Dislocation Network ◽  
Weak Beam ◽  
Phosphorus Doped

A (111) phosphorus-doped Si specimen, thinned to give a TEM foil of thickness ∼ 150nm, contained a dislocation network lying on the (111) plane. The dislocation lines were along the three <211> directions and their total Burgers vectors,ḇt, were of the type , each dislocation being of edge character. TEM examination under proper weak-beam conditions seemed initially to show the standard contrast behaviour for such dislocations, indicating some dislocation segments were undissociated (contrast A), while other segments were dissociated to give two Shockley partials separated by approximately 6nm (contrast B) . A more detailed examination, however, revealed that some segments exhibited a third and anomalous contrast behaviour (contrast C), interpreted here as being due to a new dissociation not previously reported. Experimental results obtained for a dislocation along [211] with for the six <220> type reflections using (g,5g) weak-beam conditions are summarised in the table below, together with the relevant values.

Multislice calculations of RHEED patterns from vicinal Si (001)

1993 ◽  
Vol 51 ◽  
pp. 1000-1001
Author(s):  
Scott Lordi
Keyword(s):  
Misorientation Angle ◽  
Incident Angle ◽  
Incident Beam ◽  
Experimental Results ◽  
Bragg Condition ◽  
Vicinal Surfaces ◽  
Kinematic Theory ◽  
Step Edges

Vicinal Si (001) surfaces are interesting because they are good substrates for the growth of III-V semiconductors. Spots in RHEED patterns from vicinal surfaces are split due to scattering from ordered step arrays and this splitting can be used to determine the misorientation angle, using kinematic arguments. Kinematic theory is generally regarded to be inadequate for the calculation of RHEED intensities; however, only a few dynamical RHEED simulations have been attempted for vicinal surfaces. The multislice formulation of Cowley and Moodie with a recently developed edge patching method was used to calculate RHEED patterns from vicinal Si (001) surfaces. The calculated patterns are qualitatively similar to published experimental results and the positions of the split spots quantitatively agree with kinematic calculations.RHEED patterns were calculated for unreconstructed (bulk terminated) Si (001) surfaces misoriented towards [110] ,with an energy of 15 keV, at an incident angle of 36.63 mrad ([004] bragg condition), and a beam azimuth of [110] (perpendicular to the step edges) and the incident beam pointed down the step staircase.

Sign in / Sign up

Export Citation Format

Share Document