Research on the Influence of Non Identical Position of Acoustic Ranging in AUV Underwater Guidance

2021 ◽  
Author(s):  
Jun Cao ◽  
Zaiming He ◽  
Weizhe Xu ◽  
Shenshen Yang ◽  
Wei Zhang ◽  
...  
Keyword(s):  
Acoustic Ranging ◽  
Identical Position

Yu.F. Samarin’s Model of the National State: Between Archaic and Modern

2019 ◽  
Vol 54 ◽  
pp. 149-155
Author(s):  
Alexey B. Panchenko
Keyword(s):  
Rural Community ◽  
Fundamental Difference ◽  
The State ◽  
Basic Unit ◽  
National State ◽  
Basic Model ◽  
The Face ◽  
Identical Position ◽  
Ethnocultural Community ◽  
Communicative Space

Yu. F. Samarin’s works are traditionally viewed through the prism of his affiliation with Slavophilism. His view of the state is opposed to the idea of the complex empire based on unequal interaction of the central power with the elite of national districts. At the same time it was important for Samarin to see the nation not as an ethnocultural community, but as classless community of equal citizens, who were in identical position in the face of the emperor. Samarin’s attitude to religion and nationality had pragmatic character and were understood as means for the creation of the uniform communicative space inside the state. This position for the most part conformed with the framework of the national state basic model, however there still existed one fundamental difference. Samarin considered not an individual, but the rural community that owned the land, to be the basic unit of the national state. As the result the model of national state was viewed as the synthesis of modernistic (classlessness, pragmatism, equality) and archaic (communality) features.

Securing peer-assisted indoor localization leveraging acoustic ranging

2019 ◽  
Vol 81 ◽  
pp. 58-77
Author(s):  
Shaoyong Du ◽  
Jingyu Hua ◽  
Sheng Zhong
Keyword(s):  
Indoor Localization ◽  
Acoustic Ranging

Advances in active acoustic ranging

2019 ◽  
Vol 38 (11) ◽  
pp. 843-849 ◽  
Author(s):  
Asbj⊘rn L. Johansen ◽  
William T. Allen ◽  
Roger Goobie ◽  
Nicholas Bennett ◽  
Benny Poedjono ◽  
...  
Keyword(s):  
Relative Position ◽  
Marked Improvement ◽  
Critical Parameter ◽  
Turnaround Time ◽  
Seismic Interpretation ◽  
Imaging Data ◽  
Data Set ◽  
Acoustic Ranging ◽  
Improve Accuracy ◽  
Logging Tool

Recent advances in the processing and interpretation of sonic imaging surveys warrant a fresh look at the performance of active acoustic ranging for locating wellbores. The interpretation of results from sonic imaging surveys typically has been done in workflows similar to classic seismic interpretation, where the data are projected into a 2D plane and reflective features are picked. These sonic imaging workflows require significant time and expertise to execute. The reflected arrival events typically are obscured by higher amplitude borehole modes, and the migration workflow needs numerous critical parameter choices that require interpreting the raypath type and azimuth of the reflected arrivals. When used for acoustic ranging, additional challenges are present, particularly in situations where the logging tool rotates and the relative position of the target well changes with depth. This may occur when the logging or target well trajectories have a curved shape, since determining the direction and distance to the target well then requires careful interpretation of migration image amplitudes. We demonstrate how a newly developed automated approach to the interpretation of sonic imaging data helps improve accuracy and removes interpreter bias while simplifying the processing chain and reducing turnaround time. We compare our results to what has been obtained previously by using the same data set. We achieve a marked improvement in accuracy and consistency using this new technique.

Prediction of Ship Acoustic Signature Due to Fluid Flow

2007 ◽  
Author(s):  
Mae L. Seto ◽  
Rubens Campregher ◽  
Stefan Murphy ◽  
Julio Militzer
Keyword(s):  
Flow Field ◽  
Immersed Boundary ◽  
Noise Power ◽  
Far Field ◽  
Acoustic Analogy ◽  
Noise Component ◽  
Cavitation Inception ◽  
Flow Noise ◽  
Acoustic Signature ◽  
Acoustic Ranging

The contribution of flow noise to the radiated acoustic signature of CFAV Quest is of interest. Quest is the research ship used by Defence R&D Canada as a quiet platform. It is difficult to identify the flow noise component in an acoustic ranging so there is interest in predicting the flow noise as a first step towards extracting it from range measurements. Below propulsor cavitation inception speeds, machinery-induced noise dominates. While flow noise does not usually dominate in the presence of machinery-induced noise or propulsor cavitation, it is unclear what fraction of the total noise power flow noise constitutes. A direct numerical simulation for a complex ship geometry was impractical so an alternative approach was sought. An immersed boundary method was used to model the presence of the ship in the flow domain. The unsteady flow field was calculated using a finite volume method over an unstructured Cartesian grid. The flow field around Quest in straight and level flight was calculated at Reynolds numbers between 1.8×108 and 4.3×108, corresponding to a full-scale speed range of 4 to 10 knots. Results from such flow field predictions become the hydrodynamic sources in the integrals of Lighthill’s acoustic analogy to predict the far-field acoustic signature from the flow past the hull. These far-field predictions consist of computing the propagation and radiation of the hydrodynamic sources. This assumes noise generation and its propagation are decoupled. Under certain circumstances, knowledge of the predicted flow component helps to extract it from a standard acoustic ranging.

scholarly journals Primary structure of the ovine pituitary follitropin β-subunit

1981 ◽  
Vol 197 (3) ◽  
pp. 541-552 ◽  
Author(s):  
M R Sairam ◽  
N G Seidah ◽  
M Chrétien
Keyword(s):  
Polypeptide Chain ◽  
Base Change ◽  
Beta Subunit ◽  
Tryptophan Residue ◽  
Edman Degradation ◽  
Amino Acid Residues ◽  
Serine Residue ◽  
Terminal Sequence ◽  
Single Base Change ◽  
Identical Position

The complete amino acids sequence of the ovine pituitary follitropin beta-subunit was established by studying the tryptic, chymotryptic and thermolytic peptides. The N-terminal sequence of the subunit was confirmed by subjecting the oxidated protein to Edman degradation in an automated sequenator. Automated Edman degradation of the reduced and alkylated (with iodo [14C]acetamide) beta-subunit indicated that most of the molecules used in the sequence studies had lost the N-terminal serine residue. This also confirmed the location of the first five half-cystine residues in the sequence. The proposed structure shows the presence of 111 amino acid residues with the two oligosaccharide moieties linked to asparagine residues located at positions 6 and 23. Heterogeneity occurs at both the termini of the polypeptide chain. Comparison of the sequence of beta-subunit of the ovine hormone with that proposed for human follitropin beta-subunit shows the absence of any deletions in the middle of the peptide chain. Of the 13 replacements, 11 residues can be explained on the basis of a single base change in the codon. The single tryptophan residue of the follitropin occupies an identical position in all the four species that have been studied. The region corresponding to residues 63-105 of the ovine beta-subunit is highly conserved in all the species.

Physical localization of active and inactive rRNA gene loci in Hordeum marinum spp. gussoneanum (4x) by in situ hybridization

Genome ◽  
1992 ◽  
Vol 35 (6) ◽  
pp. 1032-1036 ◽  
Author(s):  
Ib Linde-Laursen ◽  
Elly Ibsen ◽  
Roland Von Bothmer ◽  
Henriette Giese
Keyword(s):  
In Situ Hybridization ◽  
Silver Staining ◽  
Chromosome Pair ◽  
Extra Chromosome ◽  
Rrna Gene ◽  
Morphological Similarity ◽  
Identical Position ◽  
Additional Support ◽  
Two Populations

Two populations of the diploid and 10 populations of the tetraploid cytotype of Hordeum marinum ssp. gussoneanum were studied for the presence of chromosomal segments harbouring rDNA. Conventional cytological methods established the presence of only one satellited (SAT) chromosome pair in both cytotypes. This was supported by silver staining revealing two NORs and two standard-sized nucleoli. Two additional micronucleoli were observed in a few interphases of two tetraploid populations indicating the presence of an extra chromosome pair with very low nucleolus-forming activity. In situ hybridization with the wheat rDNA probe pTA71 identified intense signals at the nucleolar constrictions of the SAT chromosomes of both cytotypes and weaker signals in a chromosome pair of the tetraploid cytotype, morphologically similar to the SAT chromosomes but without visible nucleolar constrictions. This confirms the presence of rDNA in two chromosome pairs in the tetraploid cytotype. The morphological similarity between these two pairs and the SAT-chromosome pair of the diploid cytotype as well as an identical position of the signals in all three pairs give additional support to an autoploid origin of the tetraploid cytotype. The rDNA at the nucleolar constrictions consisted of two segments of condensed rDNA of different sizes connected by diffuse rDNA. The rDNA of the chromosome pair without nucleolar constrictions was condensed supporting that this conformation is connected with inactivity. The tripartite structure of the rDNA at the nucleolar constrictions corresponds to similar tripartite structures observed after silver staining and Giemsa C-banding.Key words: in situ hybridization, rDNA location, Hordeum marinum, autoploidy, inactive NORs.

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