Development of an automated acoustic calibration system for fisheries acoustic surveys

Since the development of the 5-point verbal and 11-point numerical scales for measuring noise annoyance by the ICBEN Team 6, these scales have been widely used in socio-acoustic surveys worldwide, and annoyance responses have been easily compared internationally. However, both the top two categories of the 5–point verbal scale and the top three ones of the 11-point numerical scale are correspond to high annoyance, so it is difficult to precisely compare annoyance responses. Therefore, we calculated differences in day–evening–night-weighted sound pressure levels (Lden) by comparing values corresponding to 10% highly annoyed (HA) on Lden_%HA curves obtained from measurements in 40 datasets regarding surveys conducted in Japan and Vietnam. The results showed that the Lden value corresponding to 10% HA using the 5-point verbal scale was approximately 5 dB lower than that of the 11-point numerical scale. Thus, some correction is required to compare annoyance responses measured by the 5-point verbal and the 11-point numerical scales. The results of this study were also compared with those of a survey in Switzerland.

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New programmable calibration system for highly accurate AC current measurements at NIS, Egypt

2008 43rd International Universities Power Engineering Conference ◽

10.1109/upec.2008.4651674 ◽

2008 ◽

Author(s):

A. H. Ahmed ◽

M. Halawa ◽

S. M. Moussa ◽

E. H. Shehab_Eldin ◽

E. M. El-Refaee

Keyword(s):

Calibration System ◽

Ac Current

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Laser beam calibration for wood surface colour treatment

European Journal of Wood and Wood Products ◽

10.1007/s00107-021-01704-3 ◽

2021 ◽

Author(s):

M. Jurek ◽

R. Wagnerová

Keyword(s):

Laser Beam ◽

Power Control ◽

Wood Surface ◽

Laser Power ◽

Production Quality ◽

Chemical Processes ◽

Continuous Control ◽

Calibration System ◽

Laser Engraving ◽

Wood Surfaces

AbstractLaser engraving of photographs on wood surfaces is a challenging task. To optimize the outcome and production quality it is necessary to control every aspect of the laser engraving process. Most of the production machines and technologies overall are mainly focused on laser power control. However, with other systems and deeper knowledge of the wood characteristics it is possible to achieve even better quality. This paper deals with enlarging the number of achievable shades of burned wood and its optimization. A calibration system was developed to control colour shades of engraved wood with a combination of laser power and optic focus. With this approach it is possible to widen achievable palette of engraved shades by continuous control of chemical processes of laser and wood interaction. The production is divided into wood burning and wood carbonization by variation of laser beam focus.

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A new look on the morphometric characteristics of Congridae leptocephali from the southern Adriatic Sea

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315421000229 ◽

2021 ◽

pp. 1-5

Author(s):

M. Mandić ◽

I. Leonori ◽

A. De Felice ◽

S. Gvozdenović ◽

A. Pešić

Keyword(s):

Fish Species ◽

Adriatic Sea ◽

Pelagic Fish ◽

Morphometric Parameters ◽

Morphological Features ◽

Morphometric Characteristics ◽

Small Pelagic Fish ◽

Acoustic Surveys ◽

Western Side ◽

Conger Conger

Abstract Anguillid leptocephali of three Congridae species (Conger conger, Ariosoma balearicum and Gnathophis mistax) were caught as bycatch of pelagic trawls during acoustic surveys targeting small pelagic fish species in the southern Adriatic Sea, carried out under the framework of the Italian MEDIAS project (western side) and its extension in the ambit of the FAO AdriaMed project (eastern side). Results refer to the findings of Congridae leptocephali during surveys conducted in 2011, 2014, 2015 and 2016. A total of 25 specimens were caught and analysed (morphological features and pigmentation patterns). Leptocephali of Conger conger were found in the range of 8.4–13.1 cm total length (TL) (between 50 and 132 m depth), Ariosoma balearicum from 9.7–12.2 cm TL (between 50 and 128 m depth) and for Gnathophis mystax in the range from 6.4–11.7 cm TL (between 40 and 79 m depth). The results indicate that the southern Adriatic Pit could be the spawning area of these species in the Adriatic Sea. Present data represent a contribution to existing knowledge about the ecology of leptocephali from the Congridae family in the southern Adriatic Sea, and also indicate the existence of differences in morphometric parameters between different areas, that is, the possibility of the existence of new geographic lines within the genus Ariosoma in the Adriatic Sea.

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