background preloader

Welcome!

Welcome!
Related:  Hydrography

seiche engineering Surveying, cadastral surveying, laser surveying, hydrographic surveying, mining surveying, land surveying | A Life Without Limits There are many specialisations within Surveying you can choose from, depending on your interests and whether you want to work in the city, country or coastal areas. Land Surveying Land (Cadastral) Surveyors determine and advise on property boundaries when land is subdivided, bought or sold. Cadastral Surveyors need to hold a special license as their findings determine the status of land ownership. Engineering New freeway systems, bridges and high-rise buildings all need precise planning. Mining Mining Surveyors design and measure mines, tunnels and other underground works. Hydrographic Hydrographic Surveyors map the sea floor and other waterways. Environmental Projects Surveyors are integral to sustainable development and environmental projects as they measure the change in geographic information. Geodesy Geodesy is a science of the measurement and mapping of the earth’s surfaces. Topographic Topographic Surveyors measure elevation points on land and the environment. Remote Sensing Archaeology

sis_cube_about About the implementation of CUBE in SIS The CUBE (Combined Uncertainty and Bathymetry Estimator) algorithm is developed at The Centre for Coastal and Ocean Mapping (C-COM)/Joint Hydrographic Centre (JHC) at University of New Hampshire. The algorithm is available as a library and is used inside one separate module in SIS. The CUBE algorithm can be used as an alternative data gridding and data cleaning method in SIS. The gridding and data cleaning is a default process done by the GridEngine. Cube is not available when logging data. The CUBE module in SIS receives ping data on UDP where depth and angle gate are applied to the data. The GridEngine holds both a processing grid and a display grid. The implementation of LOD in the GridEngine also results in less sensitivity to the grid cell size when displaying grids - see the next four figures. SIS must chose between either GridEngine or CUBE grids. CUBE also need some amount of data density to do the gridding.

Improving on CUBE for Bathymetric Modeling In a previous post I briefly described a parallel processing approach to bathymetric estimation from soundings. In the post I mentioned that I believe I had improved on the CUBE (Combined Uncertainty Bathymetric Estimation) algorithm. Well it's not very fair to make a statement like that without at least trying to substantiate it - so here goes. CUBE is really designed to model uncertainty and create bathymetric terrain models from multi-beam echo sounder (MBES) data. It is implemented in software products such as Fledermaus. The CUBE algorithm uses a sensor model to assign uncertainties in the vertical and horizontal domain to each sounding before estimation. Fig 1: Typical uncertainty in the vertical domain for MBES data. What I wanted to achieve was a CUBE-like algorithm that was suitable for highly heterogeneous sounding data sets (i.e. a combination of single-beam echo sounder data, MBES data and even data picked from seismic acquired over multiple years / decades). Desirable Case:

Canadian Hydrographic Service Preface The advent of satellite positioning, multi-transducer and multibeam echo sounding systems and sophisticated data processing tools have drastically modified the way hydrographic surveys are conducted. Management tools such as ISO 9001:2000 have also had an impact on the methods used to ensure quality assurance. The Canadian Hydrographic Service (CHS) Survey Standing Orders, as they were written in the 1980’s and 1990’s, no longer reflect the standards and the methods of work required to properly conduct a hydrographic survey. The CHS Standards for Hydrographic Surveys is the document that specifies the requirements for hydrographic surveys in order that hydrographic data is collected according to specific standards. The Quality Management System (QMS) Hydrographic Survey Procedures detail the procedures, the methods, the equipment and the steps required to obtain the accuracies specified in the CHS Standards for Hydrographic Surveys. Table of Contents Record of Changes 4.3 Blunders

Section 5: Theory, distribution and examples of survey error | NZIS Introduction This section may be described as ‘higher surveying? but knowledge of it is essential and fundamental to the conduct of cadastral surveys. When surveyors make any form of measurement, they quickly find that with repetition the results differ, although marginally. A simple example would be the difference between the faces when observing with a theodolite. What then should be the value of the measurements? Note the generic term is to be distinguished from a ‘mistake? What to do with errors is a major problem for surveyors, possibly the major problem. The best advice is to measure carefully and accurately using well-adjusted, maintained and standardised equipment suitable for the job in hand, and applying the appropriate techniques and methodology to reduce the errors to a minimum according to the accepted relevant standard. The full theory and treatment of errors is complex and beyond the scope of this chapter. A brief discussion on the subject appears in Chapter 3 section 2.

Tower Software Software Page Online Navigation Software - Cable Management and Support This program is designed to carry out real-time data acquisition for Submarine Cable Installation (Surface Lay and Ploughing) and Repair/Maintenance, Plough/Burial Assessment Surveys (PAS/BAS), Route Clearance, Pre-Lay Grapnel (PLGR), Post Lay Inspection and Burial (PLIB), Shore-end and MOD operations. Tower has been involved with Global Marine Systems Ltd. and its predecessors since early 1995, to supply software, personnel, surveyor and Officer training, and support. In addition to the standard features, this program has the following capabilities: Totally user configurable I/O’s (Input/Outputs), plus existing I/O’s for all of the following Ploughs/ ROV’s/Seabed tractors/Sleds (SMD, Perry Slingsby vehicles/interface units etc.) for bi-directional data flow of navigation (USBL position, KP and DCC and offsets) burial depth, tensions, tow forces, heading, depth, skid heights and all other vehicle data.

Spreadsheet for coordinate calculations | Business and government Our coordinate calculations spreadsheet enables you to carry out common calculations with coordinates. It includes a full set of Transverse Mercator projection functions, which allows you to: Convert latitude and longitude to grid eastings and northings for any Transverse Mercator map projection, including the Ordnance Survey National Grid – and vice versa.Compute local scale factor at any point on the grid, and computer grid convergence, t-T and true azimuth between any pair of points on the grid.Convert latitude and longitude coordinates to cartesian XYZ coordinates and vice versa.Convert latitude and longitude coordinates in any coordinate system to any other coordinate system. For instance, GPS coordinates may be converted to Ordnance Survey National Grid coordinates for anywhere in Great Britain with an accuracy of about 5 metres.Reformat latitude and longitude coordinates between: Degrees, Minutes & Seconds; decimal Degrees; and Degrees & Decimal Minute formats.

Term Dates Academic Year 2014/2015: standard term dates Autumn Term Monday 22 September 2014 – Term begins with enrolment/induction Monday 29 September 2014 – Teaching begins Friday 12 December 2014 – Term ends Reading week: week commencing Monday, 3rd November 2014 (week 6 of teaching) Spring Term Monday 5 January 2015 – Term begins Friday 27 March 2015 – Term ends Reading week: week commencing Monday 16th February 2015 (week 7 of teaching) Summer Term

HSL – Higgs Survey Launch | Higgs Hydrographic Tek If you’re in the market for a safe, versatile and easy to operate small survey vessel, look no further. Higgs Hydrographic Tek is proud to announce the Higgs Survey Launch H*S*L. A stable, practical, tough, seaworthy boat that’s perfect for both single beam and multibeam surveys. The design offers incredible stability and sea keeping abilities, resulting in the most comfortable ride in its class. The H*S*L handles exceptionally well even in surf or rough conditions. The Higgs Survey Launch boasts an exceptionally large carrying capacity at low speeds for easy and accurate surveying. The Higgs Survey Launch H*S*L can carry single-beam , multi-beam , bathymetric or side scan payloads .

Development and demonstration of a Digital Terrain Model and 3D viewing software - DTM and 3D Viewer - Products - Geo-Seas Development and demonstration of a Digital Terrain Model and 3D viewing software Following the user consultation Geo-Seas undertook developments for: Definition of the characteristics of bathymetric grids (digital terrain models) as required by end-users Specification of procedures for combining different data sources and features in a target digital terrain model (DTM) Development of a pilot DTM as a case study in order to evaluate the feasibility of generating such grids and services in accordance with end-user requirements whilst taking into account the constraints resulting from the use of multiple datasets from a variety of data sources (the data being made available by Geo-Seas data centres). The analysis has resulted in a document with a list and definitions of DTM products with guidelines for description and representation based on user requirements. A 3D visualisation tool (3D Viewer) based on the existing open source NASA World Wind JSK application has been developed.

Articles of the Hydrographic Service | Hydrography Staff members of the Hydrographic Service regularly write articles for journals, some of which can be found elsewhere on the internet. The rest is available for download here. 'Charting a dynamic seafloor: how an excellent survey becomes a poor dataset, and what to tell the mariner'. Leendert Dorst, in: Lighthouse, edition 82 (May 2014). ‘GNSS Based Hydrographic Surveying: clear advantages and hidden obstacles’.

Coordinate systems at sea | Hydrography For safe navigation at sea, it is important to know your position as well as the positions of obstacles. Positions are expressed in coordinates. Positions at sea are expressed in latitude and longitude, and height or depth with respect to a specified water level. As with your own position, nautical charts and datasets also make use of a coordinate reference system. The choice of coordinate reference system influences point, line and area calculations. In the Netherlands, the Netherlands Cadastre, Land Registry and Mapping Agency (Kadaster), the Directorate-General for Public Works and Water Management (Rijkswaterstaat) and the Hydrographic Service of the Royal Netherlands Navy share responsibility for the Dutch coordinate reference systems.

Vertical Offshore Reference Frames Vertical Offshore Reference Frames (VORF) The Vertical Offshore Reference Frames (VORF) research project is an ongoing collaboration between University College London and the United Kingdom Hydrographic Office (UKHO). It commenced in 2005 with the aim of providing the ability to transform vertical height information in the coastal and offshore zones between reference levels such as: Chart Datum (the reference level for nautical charts)Mean Sea LevelLowest Astronomical TideMean Low Water SpringsEuropean Terrestrial Reference Frame (ETRF89)Ordnance Datum (Newlyn)Ordnance Datum (Poolbeg) The VORF solution for UK and Ireland was completed in 2008 and has become an essential tool in operational hydrography. Current focus is on extending the concept globally for the offshore zone beyond 12 nautical miles from land.

Related: