The International Hydrographic Organization (IHO) was established in 1921 to support safety of navigation and protect the marine environment. It coordinates activities between national hydrographic offices to promote standardization and sharing of hydrographic data. The IHO develops standards for hydrographic and nautical charting used by its 85 member countries. It directs programs like the General Bathymetric Chart of the Oceans in partnership with the Intergovernmental Oceanographic Commission.
Hydrographic survey is the survey of physical features present underwater.
This slide briefs you about the definition of the survey, its application, use, etc. It also discusses the sounding process used in the hydrographic survey.
Hydrographic survey is the survey of physical features present underwater.
This slide briefs you about the definition of the survey, its application, use, etc. It also discusses the sounding process used in the hydrographic survey.
It’s hard to get a highly Paid Job without any information & Skills. All the corporate culture needs prior experience. They don’t want to waste their resources to the people who don’t know. SO come to us, Get yourself trained by knowing the history of the field, business structure, your route of finding a place in one of the biggest job producing markets of the world with just a little effort to develop the skills. TSK- Training For skills and knowledge is the best institute in Rawalpindi Islamabad Pakistan for trainings and courses which leads you towards highly paid jobs. For more info visit www.trainingcourses.com.pk
Hydrographic surveying or bathymetric surveying is the survey of physical features present underwater. It is the science of measuring all factors beneath water that affect all the marine activities like dredging, marine constructions, offshore drilling etc.
In this report, I shall discuss the importance and applications of hydrographic surveying, the devices used for the hydrographic survivor, how he uses them, and how do they work.
2013 PLSC Track, Hydrographic Surveying and GIS by Carlos CaceresGIS in the Rockies
This presentation is to inform the audience about hydrographic surveying done at Denver Water’s reservoirs. In this presentation, I will show how we collect, process, and use the data. I will discuss the software used such as Hypack software, AutoCAD Civil 3D, and most importantly ArcGIS. We are able to map the depths of the reservoirs to determine water volumes that will be used by Water Recourses Analysis Division.
Reconnaissance for Hydrographic Survey ProjectNzar Braim
Reconnaissance for Hydrographic Survey Project
The system is able to withstand the harsh environment of the nearshore and acquire beach profile information across the surf zone. This paper describes the system and results of a comparison in Myrtle Beach, S.C., between surveys collected over a 3- day period by the personal watercraft system and by a similar system mounted aboard a traditional coastal survey vessel.
The bathymetric measurements for the personal watercraft-mounted echosounder surveying system display mean repetitive differences of 6 cm.
This workshop is an introductory course in Hydrographic surveying.
It is designed for surveyors, engineers, survey technicians, dredge operators, and hydrographers.
The course focuses on theoretical principles of hydrographic surveying, project description, operation, and map production.
Greetings all,
This month’s newsletter is devoted to Data Assimilation and its techniques and progress for operational oceanography.
Gary Brassington is first introducing this newsletter with a paper telling us about the international summer school for “observing,
assimilating and forecasting the ocean” which will be held in Perth, Western Australia in 11-22 January 2010
(http://www.bom.gov.au/bluelink/summerschool/). The course curriculum will include topics covering the leading edge science in
ocean observing systems, as well as the latest methods and techniques for analysis, data assimilation and ocean modeling.
Scientific articles about Data Assimilation are then displayed as follows: The first article by Broquet et al. is dealing with Ocean
state and surface forcing correction using the ROMS-IS4DVAR Data Assimilation System. Then, Cosme et al. are describing the
SEEK smoother as a Data Assimilation scheme for oceanic reanalyses. The next article by Brankart et al. is displaying a synthetic
literature review on the following subject: Is there a simple way of controlling the forcing function of the Ocean? Then Ferry et al.
are telling us about Ocean-Atmosphere flux correction by Ocean Data Assimilation. The last article by Oke et al. is dealing with
Data Assimilation in the Australian BlueLink System.
The next October 2009 newsletter will review the current work on ocean biology and biogeochemistry.
We wish you a pleasant reading!
It’s hard to get a highly Paid Job without any information & Skills. All the corporate culture needs prior experience. They don’t want to waste their resources to the people who don’t know. SO come to us, Get yourself trained by knowing the history of the field, business structure, your route of finding a place in one of the biggest job producing markets of the world with just a little effort to develop the skills. TSK- Training For skills and knowledge is the best institute in Rawalpindi Islamabad Pakistan for trainings and courses which leads you towards highly paid jobs. For more info visit www.trainingcourses.com.pk
Hydrographic surveying or bathymetric surveying is the survey of physical features present underwater. It is the science of measuring all factors beneath water that affect all the marine activities like dredging, marine constructions, offshore drilling etc.
In this report, I shall discuss the importance and applications of hydrographic surveying, the devices used for the hydrographic survivor, how he uses them, and how do they work.
2013 PLSC Track, Hydrographic Surveying and GIS by Carlos CaceresGIS in the Rockies
This presentation is to inform the audience about hydrographic surveying done at Denver Water’s reservoirs. In this presentation, I will show how we collect, process, and use the data. I will discuss the software used such as Hypack software, AutoCAD Civil 3D, and most importantly ArcGIS. We are able to map the depths of the reservoirs to determine water volumes that will be used by Water Recourses Analysis Division.
Reconnaissance for Hydrographic Survey ProjectNzar Braim
Reconnaissance for Hydrographic Survey Project
The system is able to withstand the harsh environment of the nearshore and acquire beach profile information across the surf zone. This paper describes the system and results of a comparison in Myrtle Beach, S.C., between surveys collected over a 3- day period by the personal watercraft system and by a similar system mounted aboard a traditional coastal survey vessel.
The bathymetric measurements for the personal watercraft-mounted echosounder surveying system display mean repetitive differences of 6 cm.
This workshop is an introductory course in Hydrographic surveying.
It is designed for surveyors, engineers, survey technicians, dredge operators, and hydrographers.
The course focuses on theoretical principles of hydrographic surveying, project description, operation, and map production.
Greetings all,
This month’s newsletter is devoted to Data Assimilation and its techniques and progress for operational oceanography.
Gary Brassington is first introducing this newsletter with a paper telling us about the international summer school for “observing,
assimilating and forecasting the ocean” which will be held in Perth, Western Australia in 11-22 January 2010
(http://www.bom.gov.au/bluelink/summerschool/). The course curriculum will include topics covering the leading edge science in
ocean observing systems, as well as the latest methods and techniques for analysis, data assimilation and ocean modeling.
Scientific articles about Data Assimilation are then displayed as follows: The first article by Broquet et al. is dealing with Ocean
state and surface forcing correction using the ROMS-IS4DVAR Data Assimilation System. Then, Cosme et al. are describing the
SEEK smoother as a Data Assimilation scheme for oceanic reanalyses. The next article by Brankart et al. is displaying a synthetic
literature review on the following subject: Is there a simple way of controlling the forcing function of the Ocean? Then Ferry et al.
are telling us about Ocean-Atmosphere flux correction by Ocean Data Assimilation. The last article by Oke et al. is dealing with
Data Assimilation in the Australian BlueLink System.
The next October 2009 newsletter will review the current work on ocean biology and biogeochemistry.
We wish you a pleasant reading!
We offer you this guide to shed light on the question you are probably asking yourself: «What is the use of oceanography?».
By tracing the history of marine science, we explain how oceanographers have been able to put the oceans at the heart of their work and demonstrate the crucial role they play in the planetary balance.
Convinced that the prerequisite for any action is a better understanding of the issues by science, we hope that this guide to oceanography will help to crystalise on the issues and challenges posed by science. We hope that it will help lay the foundation for buil- ding a common and shared ocean culture.
Editorial – July 2010
Greetings all,
This month’s newsletter is devoted to recent studies in coastal oceanic systems.
To start with, Le Traon is introducing this newsletter telling us about the SNOCO initiative.
Scientific articles about recent studies in coastal oceanic systems are then displayed as follows: First, Ménesguen et al. are telling
us about Ulva mass accumulations on Brittany beaches and remedies found to solve this problem. Then, Ardhuin presents his
work about wave hindcasting and forecasting at Previmer within the European project “Integrated Ocean waves for Geophysical
and other Applications”. Third, Faucher et al. provide a description of a coupled Atmosphere-Ocean-Ice forecast system for the
Gulf of St Lawrence in Canada, which has been installed in experimental mode at the Canadian Meteorological Centre. Finally,
Marchesiello et al. are talking about regional ocean forecasting and downscaling strategy at IRD for coastal and submesoscale
phenomena. They have developed a downscaling strategy based on the Regional Ocean Modeling System and produced a new
demonstrator with data assimilation in the Chile oceanic area.
The next October 2010 newsletter will display papers about the Marginal Seas in the MyOcean project.
We wish you a pleasant summer!
CHINA’S SUSTAINABLE OCEAN AND COASTAL DEVELOPMENT STRATEGYIN 21ST CENTURYIwl Pcu
Ocean is a treasure house of resources, including minerals (sand, polymetallic nodules, cobalt crust, hydrothermal vents) energy (oil and gas, gas hydrate)and food ( fish etc.) for sustainable human development .
Blue economy is a term in economics relating to the exploitation, preservation and regeneration of the marine environment. Its scope of interpretation varies among organizations.According to the World Bank, the blue economy is the "sustainable use of ocean resources for economic growth, improved livelihoods, and jobs while preserving the health of ocean ecosystem." European Commission defines it as "All economic activities related to oceans, seas and coasts.
Implementation of a high-resolution regional ocean modeling system (ROMS) for...Hafez Ahmad
The goal of this study is to develop a High-resolution Regional Ocean Model and
implement it with the help of the Regional Ocean Modeling System (ROMS) for the Bay
of Bengal which is a tropical ocean basin with three sides covered by land and an Open
Ocean on the south side. A new generation of sophisticated ocean circulation ROMS has
been specially customized for accurate simulation of the Bay of Bengal ocean systems. It
covered a wide range of features including higher-order advection schemes, accurate and
efficient physical and numerical algorithms, and several subgrid-scale parameterizations,
atmospheric, oceanic, and benthic boundary layers, several coupled models for
atmosphere, ocean, biogeochemical, and ecosystem responses. Besides, ROMS produced
a large amount of data depicting various properties of the ocean such as water temperature,
flow velocity, water density, and salinity, etc. The model outputs showed that the upper
layer circulation of the Bay of Bengal is subjected to strong seasonal variability. During
the early northeast monsoon in November, the large-scale flow pattern in the bay is
cyclonic and the western boundary current, the East Indian coastal current (EICC) flows
southward from the Bengal shelf north of 200N to the east coast of Sri Lanka. A cyclonic
gyre that forms in the southwestern Bay of Bengal during October. In December it covered
almost the whole bay from 84ºE to 93ºE and 8ºN to 18ºN. It dies off until late April where
we can only see a cyclonic eddy centered at 12ºN 86ºE. At the end of June, the circulation
in the Bay is mainly anticyclonic and dominated by four eddies centered at 10ºN 83ºE,
11ºN 86ºE, 15ºN 91ºE1, and 8ºN 86ºE. During July these anticyclonic eddies move towards
the west of the bay and by the end of August, the anticyclonic circulation of the Bay is
confined to the west of the bay. In September the anticyclonic gyre is much smaller and to
the north of the Bay. The freshwater plume along the northwest part of the Bay is well
reproduced by the model even if the river discharge was not included in the model. It does
not advect towards the interior of the bay not until the end of the southwest winds. The
represented model also shows the seasonal cycle of the surface temperature. And this
modeling tried to resolve some important atmospheric and oceanic features in reasonable
ways, analyzed and presented in this research. Some parameters such as temperature and
salinity profiles were verified with model and Argo data in the area of the Bay of Bengal.
Predicted Seagrass habitat across the shallow ocean Hafez Ahmad
this is an application of machine learning in the field of geospatial science. I have created this seagrass habitat map using Florida, USA based data with the help of ArcGIS pro and python3.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
HEAP SORT ILLUSTRATED WITH HEAPIFY, BUILD HEAP FOR DYNAMIC ARRAYS.
Heap sort is a comparison-based sorting technique based on Binary Heap data structure. It is similar to the selection sort where we first find the minimum element and place the minimum element at the beginning. Repeat the same process for the remaining elements.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024
Literature Review Basics and Understanding Reference Management.pptx
Hydrography document
1. IHO
The International Hydrographic Organization is an intergovernmental consultative and technical organization that was
established in 1921 to support safety of navigation and the protection of the marine environment.
The object of the Organization is to bring about:
1.The coordination of the activities of national hydrographic offices
2.The greatest possible uniformity in nautical charts and documents
3.The adoption of reliable and efficient methods of carrying out and exploiting hydrographic surveys
4. The development of the sciencesin the field of hydrography and the techniques employed in descriptive oceanography
The official representative of each Member Government within the IHO is normally the national Hydrographer, or
Director of Hydrography, who, together with their technical staff, meet at 3-yearly intervals in Monaco for an IHO
Assembly. The Assembly reviews the progress achieved by the Organization through its committees, sub committees
and working groups, and adopts the programmes to be pursued during the ensuing 3-year period. A Secretary General
and two Directors are elected to administer the work of the Organization during that time. The Secretary General and
Directors, together with a small international staff of technical experts in hydrography and nautical cartography and
locally recruited administrative support staff make up the IHO Secretariat in Monaco. The Secretariat of the IHO,
coordinates and promotes the IHO's programmes and provides advice and assistance to Member States and others.
History
Formation of the International Hydrographic Bureau. International cooperation in the field of hydrography began with
the first International Maritime Conference held in Washington in 1889, followed by two others in Saint Petersburg,in
1908 and 1912. In 1919, twenty-four nations met in London for a Hydrographic Conference,during which it wasdecided
that a permanent body should be created. The resulting International Hydrographic Bureau began its activity in 1921
with eighteen Member States (including the British Empire then composed of the United Kingdom and Australia). At
the invitation of H.S.H. Prince Albert I of Monaco, a noted marine scientist, the Bureau was provided with headquarters
in the Principality of Monaco. The Organization has remained in Monaco ever since, thanks to the continuing and very
generous support of the Prince's successors. During the 19th century, many maritime nations established hydrographic
offices to provide means for improving the navigation of naval and merchant vessels by providing nautical publications,
nautical charts, and other navigational services. There were substantial differences in hydrographic procedures charts,
and publications. In 1889, an International Maritime Conference was held at Washington, D.C.,and it was proposed to
establish a "permanent international commission." Similar proposals were made at the sessions of the International
Congress of Navigation held at Saint Petersburg in 1908 and the International Maritime Conference held at Saint
Petersburg in 1912.
In 1919 the hydrographers of Great Britain and France cooperated in taking the necessary steps to convene an
international conference of hydrographers. London was selected as the most suitable place for this conference,and on
24 July 1919, the First International Conference opened, attended by the hydrographers of 24 nations.
Functions
The IHO develops hydrographic and nautical charting standards. These standards are subsequently adopted and used by
its 85 member countries and others in their surveys, nautical charts, and publications. The almost universal use of the
IHO standards means that the products and services provided by the world's national hydrographic and oceanographic
offices are consistent and recognizable by all seafarers and for other users. Much has been done in the field of
standardization since the Bureau (now the IHO) was founded. The IHO has encouraged the formation of Regional
Hydrographic Commissions (RHCs). Each RHC coordinates the national surveying and charting activities of countries
within each region and acts as a forum to address other matters of common hydrographic interest. The 15 RHCs plus
the IHO Hydrographic Commission on Antarctica (HCA) effectively cover the world.The IHO,in partnership with the
Intergovernmental Oceanographic Commission (IOC),directs the GeneralBathymetric Chart of the Oceansprogramme.
.
Types of hydrography
1. Navigational hydrography :
2. Offshore hydrography :
3. Oceanic hydrography :
Horizontal Controls:
In an extensive survey, the primary horizontal control is established primarily by running theodolite and tape
traverse before the triangulation station. The traverse lines being run to following the shore lines approximately.
In survey of less extent the primary horizontal control only is required and is established by running a theodolite
2. and tape traverse sufficiently close to shore line. For rough work, the control may be established by running a
theodolite and staid traverse or plane table trader.
Vertical Controls:
These are based upon a series of bench marks established near the shore line by spirit leveling and these serve
for setting and checking tide gages etc to which the sounding are referred.
Uses for Bathymetry maps and data
1. Sustainable Resource Management:
a. Fisheries, Fisheries enhancement, Aquaculture
b. Identify spawning grounds both to aid the fishing industry and to institute and enforce conservation
regulations to protect that industry in perpetuity.
c. (seabed character, hazards to gear, damage to habitats)
d. Petroleum & Minerals
e. Exploration for hydrocarbons both to aid and regulate exploration.
f. Geological modeling of ocean basin evolution, geological and tectonic processes.
2. Environmental Stewardship:
a. Habitat Monitoring, Land Use Planning, Environmental Quality, National Heritage, Marine Protected Areas.
b. assessing the impact of coastal sediment transport and pollution,
c. offshore waste disposal; baseline monitoring
d. Planetary scale global observing systems ( e.g. GOOS, the Global Ocean Observing System, and GCOS, the
Global Climate Observing System)
e. distribution of chemical products, harmful or not, in the deep ocean),
3. Health & Safety:
a. Sewage sites, Dredge spoils disposal, Risk Reduction, Oil Spill Readiness Plans, Coastal Planning/Global
Warming Sea Level Rise, Hazard Mitigation (Earthquakes; Storm Surge & Tsunami; Seafloor Hazards)
Accident investigation
b. Most pollutants eventually end up in the ocean, and the ocean cannot be considered an infinitely large sink into
which we can forever dump wastes.
c. predictions of the future patterns of climate change on time scales of months to decades
4. Infrastructure:
a. Cables & Pipeline, Offshore Exploration & Production Platforms, Coastal Structures, Dredging, Opening
Northwest Passage
b. transport (ports, harbors, navigational hazards
c. oil platform sitting
5. Sovereignty:
a. Boundaries definition, Juridical Continental Shelf under the UNCLOS, Seabed Surveillance & Intervention,
Contraband & Drugs
b. Marine Cadaster
c. Seabed Surveillance & Intervention, Contraband & Drugs
d. Assisting the International Seabed Authority to manage the deep oceans
6. Coastal Engineering
Coastalengineering could be defined asthe technology required to measure describe or quantify the physical properties,
processes and changes in the coastal zone. Most numerical models used for modeling the coastal zone require wave
refraction information and this cannot be known without bathymetric information. Refraction is the bending of waves
due to the variation in water depths. The part of a wave in shallow water moves slower than the part of a wave in deeper
water. So when the depth under a wave crest varies along the crest, the wave bends (refracts).
7. Fundamental Science
a. Contributes to most other marine sciences
b. Valuable in the education of all marine scientists
c. climate
Speed of Sound
Sound travels about 1500 meters per second in seawater. Sound travels much more slowly in air, at about 340 meters
per second. The speed of sound in seawater is not a constant value. It varies by a small amount (a few percent) from
place to place, season to season,morning to evening, and with water depth. Although the variations in the speed of
3. sound are not large, they have important effects on how sound travels in the ocean. Sound speed is affected by the
oceanographic variables of temperature,salinity,and pressure.
The speed of sound in water increases with increasing water temperature,increasing salinity and increasing pressure
(depth). The approximate change in the speed of sound with a change in each property is:
Temperature 1°C = 4.0 m/s
Salinity 1PSU = 1.4 m/s
Depth (pressure) 1km = 17 m/s
Methods ofspeed ofsound determination
The sound velocity determination in water is one of the important issue in hydrographic surveying and should be
determined precisely to obtain correct depth. It may be determined mainly with different methods and using different
instruments as follows (de Jong et al. 2002, USAGE 2002);
a-) from empirical formulas with the information from CTD (Conductivity, Temperature, and Depth) sensor -or probe
b-) with bathythermograph
c-) with velocity meter
d-) by bar check calibration.
e-) velocity meter
Sound Velocity Determination with Empirical Formulas (equations)
The value of sound velocity, c, could be determined by means of empirical formulae using the temperature T, pressure
P (or depth D) and salinity S measured by CTD sensor. There are
Number of formulae available to calculate the sound velocity in water given in literature such as Wilson (1960), Chen
and Millero (1977), DelGrosso (1974), Mackenzie (1981), Medwin (1975). Pike and Beiboer, (1993) made an extensive
comparison of several algorithms and they suggested the following order of preference:
1- ) Chen & Millero (only for water depths less than 1000 m)
2- ) Del Grosso (only for water depths greater than 1000 m)
3- ) Mackenzie (for rapid computations in oceanic waters to 8000 m water depth)
4- ) Medwin (for rapid computations in oceanic waters to 1000 m water depth).
1: the scope of hydrography in marine research
Role of sound velocity in data collection
2: basic principles of hydrographic survey
4. Principles of cartography and projections
3: the importance of ocean and coastal mapping
4: define
5: survey standard,
Error: The difference between an observed or computed value of a quantity and the ideal or true value of that quantity
Accuracy: The extent to which a measured or enumerated value agrees with the assumed or accepted value
Precision:The degree of refinement of a value not to be confused with ACCURACY,which is the degree of
conformance with the correct value.
Uncertainty:Uncertainty is a situation which involves imperfect and/or unknown information.
Resolution:The separation by an optical system of parts of an object or of two or more objects close together. The
degree of ability to make such a separation, called resolving power, is expressed as the minimum distance between
two objects that can be separated.
Attention:
Reflection:The process whereby a surface of discontinuity turns back a portion of the incident radiation into the
medium through which the radiation approached.
Refraction:The process in which the direction of energy propagation is changed as the result of a change in density
within the propagating medium, or as the energy passes through the interface representing a density discontinuity
between two media.
Datums
Are the basis for all geodetic survey work. Datum is a base elevation used as a reference from which to reckon heights
or depths.
A tidal datum is a standard elevation defined by a certain phase of the tide. Tidal datums are used as references to
measure local water levels and should not be extended into areas having differing oceanographic characteristics without
substantiating measurements. In order that they may be recovered when needed, such datums are referenced to fixed
points known as bench marks. Tidal datums are also the basis for establishing privately owned land, state owned land,
territorial sea, exclusive economic zone, and high seas boundaries.
Chart Datum is also the level to which tidal levels and predictions are measured and is the same as the zero of the tidal
predictions.
There are two main datums.
Horizontal datums measure positions (latitude and longitude) on the surface of the Earth, while vertical datums are
used to measure land elevations and water depths.
Methods of horizontal and vertical control
1: triangulation
2: trilateration
3: mixed methods
a. Traverse
b. Not oriented open traverse
c. Oriented open traverse
d. Not oriented closed traverse
4: photogrammetry method
a. aerophotogrammetry
5: intervisibility of geodetic stations
Vertical methods
1: geometric leveling
5. 2: trigonometric levelling
3: altimetry with GPS
6: influence of coastal processes on hydrographic survey
Geodetic distance is the shortest distance
Bathymetry is a great lie
Metadata
Metadata is structured information that describes, explains, locates, or otherwise makes it easier to retrieve, use, or
manage an information resource. Metadata is often called data about data or information about information. There are
three main types of metadata:
1. Descriptive metadata describes a resource for purposes such as discovery and identification. It can include elements
such as title, abstract, author, and keywords.
2. Structural metadata indicates how compound objects are put together, for example, how pages are ordered to form
chapters.
3. Administrative metadata provides information to help manage a resource,such as when and how it was created,file
type and other technical information, and who can access it.
There are severalsubsets of administrative data; two that are sometimes listed as separate metadata types are: a. Rights
management metadata, which deals with intellectual property rights.
b. Preservation metadata, which contains information needed to archive and preserve a resource.
Metadata functions
Resource discovery
1. Allowing resources to be found by relevant criteria;
2. Identifying resources;
3. Bringing similar resources together;
4. Distinguishing dissimilar resources;
5. Giving location information.
Organizing e-resources
1. Organizing links to resources based on audience or topic.
2. Building these pages dynamically from metadata stored in databases.
Facilitating interoperability
1. Using defined metadata schemes,shared transfer protocols, and crosswalks between schemes,
resources across the network can be searched more seamlessly.
I. Cross-system search,e.g.,using Z39.50 protocol;
II. Metadata harvesting, e.g.,OAI protocol.
Digital identification
1. Elements for standard numbers, e.g., ISBN
2. The location of a digital object may also be given using:
I. a file name
II. a URL
III. some persistent identifiers, e.g., PURL (Persistent URL); DOI (Digital Object Identifier)
3. Combined metadata to act as a set of identifying data, differentiating one object from another for
validation purposes.
Archiving and preservation
1. Challenges:
I. Digital information is fragile and can be corrupted or altered;
II. It may become unusable as storage technologies change.
2. Metadata is key to ensuring that resources will survive and continue to be accessible into the future.
Archiving and preservation require special elements:
I. to track the lineage of a digital object,
II. to detail its physical characteristics, and
III. To document its behavior in order to emulate it in future technologies.
6. Transducer
A transducer is a device that converts one form of energy to another. Usually a transducer converts a signal
in one form of energy to a signal in another. Transducers are often employed at the boundaries of
automation, measurement, and control systems, where electrical signals are converted to and from other
physical quantities (energy, force, torque, light, motion, position, etc.). The process of converting one form
of energy to another is known as transduction. Types 1.Passive: Passive sensors require an externalpower source
to operate, which is called an excitation signal. The signal is modulated by the sensor to produce an output signal.
2. Active:Active sensors generate electric signals in response to an external stimulus without the need of an
additional energy source. Such examples are a thermocouple, photodiode, and a piezoelectric sensor.
3. Sensor: A sensor is a device that receives and responds to a signal or stimulus. A transducer is a term that can be
used for the definition of many devices such as sensors,actuators, or transistors.
4. Actuators: An actuator is a device that is responsible for moving or controlling a mechanism or system. It is
operated by a source of energy, which can be mechanical force, electrical current, hydraulic fluid pressure,or
pneumatic pressure,and converts that energy into motion. An actuator is the mechanism by which a control system
acts upon an environment. The control system can be simple (a fixed mechanical or electronic system), software-based
(e.g. a printer driver, robot control system), a human, or any other input.
Bidirectional : Bidirectional transducers convert physical phenomena to electrical signals and also convert electrical
signals into physical phenomena. Generate electrical power if the motor shaft is turned by an external torque.
Ideal characteristics
High dynamic range
High repeatability
Low noise
Low hysteresis
Applications
Transducers are used in electronic communications systems to convert signals of various physical forms to electronic
signals, and vice versa
Electromagnetic:
Hall effect sensors – converts a magnetic field level into an electrical signal
Electrochemical:
pH probes
Electro-galvanic fuel cells
Hydrogen sensors
Electromechanical (electromechanical output devices are generically called actuators):
Accelerometers
Air flow sensors
7. Potentiometers (when used for measuring position)
Pressure sensors
Vibration powered generators
Electroacoustic:
Geophones – converts a ground movement (displacement) into voltage (vibrations → motion of
conductor/coil → magnetic field → signal)
Gramophone pickups – (air pressure → motion → magnetic field → electrical signal)
Hydrophones – converts changes in water pressure into an electrical signal
Sonar transponders (water pressure → motion of conductor/coil → magnetic field → electrical signal)
Ultrasonic transceivers,transmitting ultrasound (transduced from electricity) as well as receiving it
after sound reflection from target objects, availing for imaging of those objects.
Electro-optical (Photoelectric):
Fluorescent lamps – converts electrical power into incoherent light
Light-emitting diodes – converts electrical power into incoherent light
Laser diodes – converts electrical power into coherent light
Photodiodes, photoresistors, phototransistors, photomultipliers – converts changing light levels into electrical
signals
Thermoelectric:
Resistance temperature detectors (RTD) – converts temperature into an electrical resistance signal
Thermocouples – converts relative temperatures of metallic junctions to electrical voltage
Thermistors (includes PTC resistor and NTC resistor)
Radioacoustic:
Radio receiver’s converts electromagnetic transmissions to electrical signals.
Radio transmitters’ converts electrical signals to electromagnetic transmissions.
WGS84
The World Geodetic System (WGS) is a standard for use in cartography, geodesy, and navigation including GPS. It
comprises a standard coordinate system for the Earth, a standard spheroidal reference surface (the datum or reference
ellipsoid) for raw altitude data, and a gravitational equipotential surface (the geoid) that defines the nominal sea level.
The latest revision is WGS 84 (WGS 1984, EPSG: 4326), established in 1984 and last revised in 2004.Earlier schemes
included WGS 72, WGS 66, and WGS 60. WGS 84 is the reference coordinate system used by the Global Positioning
System.
IHO
The law of the sea
The law of the sea is a body of customs, treaties, and international agreements by which governments maintain order,
productivity, and peaceful relations on the sea.
Theodolite
Contour line
Geodesy
Vertical and horizontal positioning
8. Role of vertical datum in ocean depth measurement
The errors and uncertainty associated with hydrographic survey
The importance of ocean and coastal mapping
Bathymetric data is important for producing navigation products (such as nautical charts) and for the advancement of
many important Earth sciences. For example, a detailed knowledge of global bathymetry is a prerequisite for mapping
the oceans and for understanding how the earth’s global systems interact. The shape of the ocean basins, ridges and
mountains influence the flow of sea water carrying heat, salt, nutrients, and pollutants. They also influence the
propagation of energy from undersea seismic events that result in potential disasters such as tsunamis. Although 71 %
of the Earth surface is covered by water, the world´s oceans remain poorly mapped.
Seafloor classification
How can you classify seafloor in vicinity of continental shelf region?
Characterize of a sea mountain
IHO
Coastal protection
Bathymetry mapping tools
Bathymetry map and navigational chart comparison
Navigation Charts are carefully constructed instruments designed to provide a basis for safely locating a vessel in
relationship to the physical geography of an area at sea,and providing information that can affect the movement of the
vessel. To do so, a Navigation Chart must:
(1) Form the base for the graphical exercise of charting;
(2) Provide information on the nature and position of navigational hazards; and
(3) Provide information on the identification and characteristics of navigational aids.
A bathymetry map is not constrained by the need to protect mariners and their vessels. The aim of the bathymetric map
is to show every “nook and cranny” of the sea floor in the best possible way permitted by the data available and the
horizontal scale of the map.
Bathymetry and hydrography of Bay of Bengal
Vertical datum
The elevation of a point can only be expressed with to the elevation of another point.it could be related to the center of
the earth,the mean surface of the ocean,the orbit of a satellite or simply a bench mark. The chosen reference to which
elevations are referred to is called a vertical datum. Currently there are about 100-200 vertical datums in the world.
Orthometric heights are defined with respect to the geoid which is an equipotential surface approximately by mean sea
level.