Vertical positioning at laser observatories

1993 ◽  
pp. 99-106 ◽  
Author(s):  
Peter J. Dunn ◽  
Mark H. Torrence ◽  
Ron Kolenkiewicz ◽  
David E. Smith
Keyword(s):  
Vertical Positioning

Photo-movement of coral larvae influences vertical positioning in the ocean

Coral Reefs ◽  
2021 ◽  
Author(s):  
Aziz J. Mulla ◽  
Che-Hung Lin ◽  
Shunichi Takahashi ◽  
Yoko Nozawa
Keyword(s):  
Coral Larvae ◽  
Vertical Positioning

scholarly journals Perspectives on Larval Behaviour in Biophysical Modelling of Larval Dispersal in Marine, Demersal Fishes

Oceans ◽  
2020 ◽  
Vol 2 (1) ◽  
pp. 1-25
Author(s):  
Jeffrey M. Leis
Keyword(s):  
Fish Larvae ◽  
Behavioural Change ◽  
Larval Fishes ◽  
Larval Behaviour ◽  
Key Issues ◽  
Modelling Effort ◽  
Validation Research ◽  
Vertical Positioning ◽  
Study Species ◽  
Demersal Fishes

Biophysical dispersal models for marine fish larvae are widely used by marine ecologists and managers of fisheries and marine protected areas to predict movement of larval fishes during their pelagic larval duration (PLD). Over the past 25 years, it has become obvious that behaviour—primarily vertical positioning, horizontal swimming and orientation—of larvae during their PLD can strongly influence dispersal outcomes. Yet, most published models do not include even one of these behaviours, and only a tiny fraction include all three. Furthermore, there is no clarity on how behaviours should be incorporated into models, nor on how to obtain the quantitative, empirical data needed to parameterize models. The PLD is a period of morphological, physiological and behavioural change, which presents challenges for modelling. The present paper aims to encourage the inclusion of larval behaviour in biophysical dispersal models for larvae of marine demersal fishes by providing practical suggestions, advice and insights about obtaining and incorporating behaviour of larval fishes into such models based on experience. Key issues are features of different behavioural metrics, incorporation of ontogenetic, temporal, spatial and among-individual variation, and model validation. Research on behaviour of larvae of study species should be part of any modelling effort.

Absolute seafloor vertical positioning using combined pressure gauge and kinematic GPS data

2009 ◽  
Vol 84 (1) ◽  
pp. 65-77 ◽  
Author(s):  
Valérie Ballu ◽  
Marie-Noelle Bouin ◽  
Stéphane Calmant ◽  
Eric Folcher ◽  
Jean-Michel Bore ◽  
...  
Keyword(s):  
Pressure Gauge ◽  
Gps Data ◽  
Kinematic Gps ◽  
Vertical Positioning

scholarly journals Positioning Evaluation of Single and Dual-Frequency Low-Cost GNSS Receivers Signals Using PPP and Static Relative Methods in Urban Areas

2021 ◽  
Vol 11 (22) ◽  
pp. 10642
Author(s):  
Rosendo Romero-Andrade ◽  
Manuel E. Trejo-Soto ◽  
Alejandro Vega-Ayala ◽  
Daniel Hernández-Andrade ◽  
Jesús R. Vázquez-Ontiveros ◽  
...  
Keyword(s):  
Urban Areas ◽  
Precise Point Positioning ◽  
Low Cost ◽  
Observation Data ◽  
Dual Frequency ◽  
Positional Accuracy ◽  
Gnss Receivers ◽  
Point Positioning ◽  
Error Circle ◽  
Vertical Positioning

A positional accuracy obtained by the Precise Point Positioning and static relative methods was compared and analyzed. Test data was collected using low-cost GNSS receivers of single- and dual-frequency in urban areas. The data was analyzed for quality using the TEQC program to determine the degree of affectation of the signal in the urban area. Low-cost GNSS receivers were found to be sensitive to the multipath effect, which impacts positioning. The horizontal and vertical accuracy was evaluated with respect to Mexican regulations for the GNSS establishment criteria. Probable Error Circle (CEP) and Vertical Positioning Accuracy (EPV) were performed on low cost GNSS receiver observation data. The results show that low-cost dual-frequency GNSS receivers can be used in urban areas. The precision was obtained in the order of 0.013 m in the static relative method. The results obtained are comparable to a geodetic receiver in a geodetic baseline of <20 km. The study does not recommend using single and dual frequencies low cost GNSS receivers based on results obtained by the Precise Point Positioning (PPP) method in urban areas. The inclusion of the GGM10 model reduces the vertical precision obtained by using low cost GNSS receivers in both methods, conforming to the regulations only in the horizontal component.

scholarly journals Modeling difference of reference surfaces of the Earth's body to solve the problem of vertical positioning

Tehnika ◽  
2016 ◽  
Vol 71 (1) ◽  
pp. 35-40
Author(s):  
Sanja S. Tucikešić ◽  
Gordana L. Jakovljević ◽  
Jelena P. Gučević
Keyword(s):  
Vertical Positioning

Vertical Positioning of Internal Molecular Scaffolding within a Single Molecular Layer

1998 ◽  
Vol 102 (47) ◽  
pp. 9550-9556 ◽  
Author(s):  
Henning Menzel ◽  
Mark D. Mowery ◽  
Mei Cai ◽  
Christine E. Evans
Keyword(s):  
Molecular Layer ◽  
Vertical Positioning ◽  
Single Molecular Layer

Horizontal and vertical labour market movements in Austria: Do occupational transitions take women across gendered lines?

2020 ◽  
pp. 001139212096976
Author(s):  
Nina-Sophie Fritsch ◽  
Bernd Liedl ◽  
Gerhard Paulinger
Keyword(s):  
Labour Market ◽  
Occupational Status ◽  
Gender Effect ◽  
Significant Decline ◽  
Gender Inequalities ◽  
Negative Effects ◽  
Horizontal Movement ◽  
Flexible Employment ◽  
Occupational Transitions ◽  
Vertical Positioning

The gendered division of occupations is a persistent characteristic of the Austrian labour market. Furthermore, we can observe more flexible employment biographies, where sequential employment episodes and occupational transitions become an important part. On this account, the article argues that both gender inequalities and labour market movements need to be examined simultaneously. The authors therefore analyse gender-(un)typed horizontal occupational transitions and their influence on the vertical positioning, based on the Austrian Micro Census (2008–2018). The results reveal that gender-typed occupational transitions are regaining relevance and that the gender effect is reversing in that women increasingly leave gender-untyped occupations. The findings also demonstrate that this gender-typed horizontal movement yields a significant decline in occupational status for women, which even increases when women become mothers. Based on their models the authors find no negative effects for fathers.

Positioning of the cp rail mount macdonald tunnel

CISM journal ◽  
1988 ◽  
Vol 42 (1) ◽  
pp. 7-16 ◽  
Author(s):  
G. Lachapelle ◽  
M. Dennler ◽  
D. Neufeldt ◽  
R. Tanaka
Keyword(s):  
Systematic Errors ◽  
Control Network ◽  
Second Phase ◽  
Surface Control ◽  
Two Phases ◽  
Canadian Pacific Railway ◽  
Vertical Positioning ◽  
Special Order

A brief description is presented of the Rogers Pass area where the 9-mile Mount MacDonald Tunnel is being built by the Canadian Pacific Railway. The two phases of the positioning task, which were conducted by Nortech Surveys (Canada) Incorporated, are described. The first phase consisted of the establishment of a surface control network, and was carried out in the summer of 1983. The exceptional positioning problems of this phase, due to the ruggedness of the area, are described together with the methods used for their solutions. The second phase consisted of the underground horizontal and vertical positioning, and was conducted during the period 1984-1987. The vertical positioning was performed using special order leveling techniques. The horizontal positioning was performed using a combination of distance, direction, and precise gyrotheodolite measurements. Related problems encountered, ranging from gyrotheodolite malfunctioning to the presence of unexpectedly large systematic errors during the last few miles of excavation, are described. The results of a post-breakthrough horizontal survey, conducted to further analyze the underground traverses, are described.

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