Between the Poles

Publicly available specification (PAS) 128 Underground utility detection, verification and location available June 30

In the UK there is a major 10-year research initiative entitled Mapping the Underworld (MTU) that seeks to address the serious social, environmental and economic consequences arising from an inability to locate – accurately and comprehensively – buried utility service infrastructure without resorting to extensive excavations (potholing). 

It is estimated that up to 4 million holes are dug in the UK road network each year in order to install or repair buried service pipes and cables. Failure to identify accurately the location of existing buried assets results in numerous practical problems, costs and dangers for utility owners, contractors and road users.

At the GEO Business 2014 conference in London, John Robinson of Subscan presented an overview of Publicly Available Specification (PAS) 128 developed under the auspices of the British Standards Institution (BSI) and sponsored by the Institution of Civil Engineers (ICE).  This is not a British (BS, EN or ISO) standard, though ICE would probably like to see it become one in the future.  The final version will be available June 30.

In the UK as in many jurisdictions there is not only a wide variation in the quality of location information about underground utility infrastructure, but there is no standard way to report the reliability of the location information about underground infrastructure.  In the U.S. there is the ASCE standard (A,B,C,D) that is widely used for classifying location information about underground infrastructure according to its estimated reliability.  I just blogged about a major national project in France aimed at classifying information about all of France's underground utility infrastructure based on accuracy (A,B,C).

The proposed quality levels proposed in Britain have some similarities to both of these,  but its focus is on process.

• QL D - Location of underground structures determined by a review of existing utility (paper) records
• QL C - A physical reconnaissance of the site has been performed identifying features of the network are visible above ground
• QL B - Remote detection technology such as electromagnetic or ground penetrating radar have been used to detect the location of the underground facilities. There is sub-classfication B1-B4 that specifies  the estimated precision of the measurements.  For example, B3 corresponds to +/- 0.5 meters.
• QL A - Verification, typically by potholing

PAS 128 is aimed at the practitioner, surveyors who make their living detecting and reporting the location of underground utilties for construction contractors and utilities.  The primary objective is to reduce risk for construction contractors.  In the UK, unlike the U.S. and Canada where we have one-call centres, if a utility is disrupted by a construction project, the liability lies entirely with the contractor.

France's national project to map underground utilities

Recently I posted an article about mapping underground utility infrastructure in cities and regions  around the world.  The most recent notable efforts in the regard are Las Vegas, which is creating a 3D model of underground and above ground infrastructure and implementing new regulations to ensure that accurate location information about underground facilities is captured, and the Region of Lombardy in Northern Italy, which has mandated that ground penetrating radar (GPR) be used by all municipalities in the region to capture location for all underground infrastructure.  But to date these efforts have been limited to municipalities or regions. 

At Geospatial World Forum 2014 in Geneva I was made aware of a project to map underground infrastructure on a national scale.  Pascal Berteaud, Director General, French National Institute of Geographic and Forest Information (IGN), referred to a large ten year, multi-billion euro project involving IGN and France's utilities to map all of France's underground utility infrastructure in 3D to an accuracy of 40 cm (about 16 inches). 

Berteaud discussed IGN's extensive use of geoinformation and innovative technologies like 3D building information modeling (BIM) for development activities in France. Geospatial information is the basis for optimization of mobility and transport, real-time information about assets, and intelligent road reference systems. In this context Berteaud emphasized that accurate 3D location is essential for effectively managing underground infrastructure and mentioned that France is developing a 3D model for its underground infrastructure and is employing advanced technologies in the project.

Accuracy of location of underground structures

The motivation for this project is a new regulation that was promulgated on 15 February 2012 titled  Decree relating to excavations near underground, overhead or underwater transmission or distribution networks.

Project managers of proposed construction projects are required to send a statement of the proposed work including a polygon delineating the area affected to the operators of utility networks operating in the area.

In return operators of utility networks must provide to the project managers plans of their underground networks in the area indicating the accuracy of the geographical location of different structures of their networks classified according to three accuracy classes.

For this purpose the Decree defines three levels of cartographic accuracy for underground structures;

Class A:  if the maximum uncertainty of location indicated by the utility operator is less than or equal to 40 cm

Class B: if the maximum uncertainty of location indicated by the utility operator is greater than that for Class A and less than or equal to 1.5 meters

Class C: if the maximum uncertainty of location indicated by the utility operator is greater than 1.5 meters , or if the operator is not able to provide the location.

The Decree states that uncertainty in the geographical location of a structure is considered likely to jeopardize the construction project or significantly impact the technical or financial conditions of its implementation when the geolocation of the structure is classified in accuracy classes B or C.  For structures falling in this category, the utility operator is required to initiate a process to reduce this uncertainty to achieve the goal of class A as quickly as possible.

Furthermore, if further investigation (typically potholing) of some structures by the contractor  is required, the cost of the investigations is assigned as follows

• The construction contractor assumes the entire cost  when the structures are assigned by the operator to accuracy class B and further investigation reveals that the actual classification is found to be Class B or Class A
• Half of the cost of the investigation is to be borne by the operator when the structures are assigned by the operator to  accuracy class C;
• All of the cost is to be borne by the operator when the structures have been assigned by the operator to accuracy class B and when the result of further investigation reveals that the actual classification is accuracy class C

Surveying underground infrastructure

Construction contractors are required to survey all new and changed underground structures.  These surveys must satisfy certain conditions.

Location coordinates of structures in an open trench must be reported by a ceritified provider (in North America I assume this would be a registered surveyor).  If remote detection technology such as GPR is employed, the firm performing this work is not required to be certified, but a certified provider must be involved in georeferencing the data.

Whatever the method of measurement used , direct or remote, the accuracy of the reported locations must be accuracy class A.

For each structure the data recorded must include

• Name of the project manager of the site
• Name of the company that provided the location information
• Name of the certified provider responsible for georeferencing
• The maximum measurement uncertainty (differentiating , where appropriate , x, y, and z )
• In the case of remote detection, the type of measurement technology used.

The data must be shared with the operator.

GeoGit - Distributed geospatial data versioning based on Git

At the Location Intelligence Summit 2014 (LI2014) in Washington, Juan Marin, CTO at Boundless,  gave an overview and demonstration of GeoGit, a distributed system for versioning geospatial data using the same philosophy as Git.  Data versioning is also known as long transactions and is a fundamamental data management technology in a number of industries.  For example, long transactions are  used by utilities to protect their production as-built information (what is actually in the ground) with a process for managing updates and new network design work.  Another example is OpenStreetMap (OSM) where there is a production OSM database that is continually being updated with crowd-sourced data.  Data versioning is an ideal strategy for managing the updates and protecting the authoritative database.

Currently GeoGit users are able to import raw geospatial data from shapefiles, PostGIS or SpatiaLite into a repository where every change to the data is tracked. These changes can be viewed in a history, reverted to older versions, branched in to sandboxed areas, merged back in, and pushed to remote repositories.  GeoGit is written in Java, and available under the BSD License.  GeoGit is a proposed LocationTech project.  LocationTech is part of the Eclipse Foundation.

Git

By way of background Git is a distributed revision control and source code management (SCM) system.  Git was initially designed and developed by Linus Torvalds for Linux kernel development in 2005.  It is free open source software distributed under the GNU General Public License (GPL)  V 2.

Every Git working directory is a full-fledged repository with complete history and full version tracking capabilities. Each local repository is standalone and is not dependent on network access to a central server. Git is known for very fast performance and for scalability. Git allows and encourages you to have multiple local branches that can be entirely independent of each other. One of the things this branching model allows you to do is to keep several concurrent branches, for example,

• Production - one branch that contains only what goes to production
• Working - another branch that you merge new work into
• Several smaller ones for new features you're working on so you can switch back and forth between them, then delete each branch when that feature gets merged into your main line

Pushing to remote repositories - When you push to a remote repository, you can choose to share one of your branches, several of them, or all of them. For example, you may only want to share your production branch.  When you push your production repository to a remote repository (called a merge) which may have been updated by several other folks while you were working, Git will detect all conflicts and has a well-defined model of an incomplete merge.  Git has multiple algorithms for completing the merge automatically. If it isn't able to complete the merge automatically, manual editing will be required.  The other important thing from a data flow perspective is that only the incremental changes are updated in the remote repository.

GeoGit

GeoGit is currently available as version 0.8.  Juan says that it is feature complete with a complete command line interface (CLI).  He  projects that V1.0 of GeoGit will be available by the summer.  In addition Integration with QGIS is in progress and it is expected that a tutorial with GeoGit running with QGIS will be available soon.  GeoGit currently only supports vector data.

Perhaps the first question is why not just use Git and a well known geodata format such as shape or GeoJSON ? Juan pointed out that you can actually do this, but there are a couple of reasons why this may not be optimal.  First of all, Git doesn't support large binary files.  Secondly, this isn't well integrated into the geospatial ecosystem so you'll have to do work to make sense of conflicts, for example.

Juan emphasized the advantages of the GeoGit approach

• No single point of failure - this is a distributed  (peer to peer) geospatial data versioning system.  As in Git everyone has a complete and independent copy of the repository.
• No single point of truth - this may not seem ideal, but as pointed out above the Git model enables you to maintain shared production and development branches.
• The GIt model is proven technology that enables scalable collaboration among remote developers

Juan described and demonstrated basic GeoGit processes including

1.  Create a repository

2. Import geospatial data, for example, shape or OSM data, into the GeoGit staging area

geogit shp import [bounding box]

geogit osm import [bounding box]

3. Edit it in the staging area

4. Commit the changes to the repository

geogit commit -m "first commit"

5. Create a branch

geogit branch <branch1>

6. Import or create some new data in the staging area, for example, digitize a building footprint polygon

7. Commit it

8. Merge it back into the main branch

geogit merge <branch1> <main>

Geogit will find, attempt to resolve and report conflicts

9. View history - view the main branch before and after the commit

10. Synchronize the repository with a remote repository

Geogit will find, attempt to resolve and report conflicts

11. Export the main branch as a shape file

geogit shp export

Following Juan's presentation, Scott Clark, Director of Geospatial Prgrams al LMN Solutions, a solution provider to the intel community described and demonstrated an application for collaborative mapping developed for DoD as a Joint Capability Technology Demonstration (JCTD) that uses GeoGit in addition to other open source geospatial tools including GeoNode, PostGIS, and GeoServer.

 Next steps

Juan outlined the main areas of focus for current and future development activities.

• High performance GeoGit server
• QGIS plug-in
• Web UI
• Python support
• Scalability - large repository support
• Performance optimization

IEA projects net $71 trilllion savings in fuels costs from decarbonizing world's energy over next 40 years

In its latest Energy Technology Perspectives 2014 (ETP 2014) the International Energy Agency (IEA) looked at the energy sector over the next 40 years.  ETP 2014 analyses three possible energy futures to 2050:

• 6°C Scenario (6DS) - where the IEA projects the world is now heading based on existing policies
• 4°C Scenario (4DS) - this scenario reflects the stated intentions by countries to cut emissions and boost energy efficiency
• 2°C Scenario (2DS) - this scenario is based on technological change tht results in a sustainable energy system with reduced greenhouse gas emissions.

In the 6°C scenario global energy demand is projected to grow by 70% over 2011 levels.  Concomitantly emissions are projected to grow by more than 60% over 2011 levels. 

Under the same projections for population and gross domestic product, the introduction of new technology and radical policy action in the 2°C scenario dramatically improves energy efficiency to limit increases in demand by 25% while emissions are cut by more than 50%.  The major sources of reduced energy demand and reduced carbon are (% of cumulative emissions reductions)

• End-use fuel and electricity efficiency 38%
• Renewables 30%
• CCS 14%
• End-use fuel switching 9%
• Power generation efficiency and fuel switching 2%

A major difference between the 2°C and 6°C scenarios is that in the 6°C scenario oil remains the most important primary energy source with demand increasing by 45%.  In contrast in the 2°C scenario new policies and technologies reduce oil demand by 30%.

In the ETP 2014 the IEA makes the case that there is a significant financial benefit in addition to environmental and social benefits from decarbonizing the energy system.  The IEA estimates that  US$ 44 trillion in additional investment in energy infrastructure is required to decarbonize the energy system inline with the 2°C scenario by 2050.   But the IEA forcasts that this expenditure is more than offset by over US$ 115 trillion in fuel savings.  The result is a net savings of US$ 71 trillion (assuming no discount).  With a 10% discount rate, the net savings are still more than US$ 5 trillion.

Coordinating public infrastructure construction projects in Bern saved SFR 7 million in first year

While in Switzerland for Geospatial World Forum 2014 I had the opportunity to spend some time with Dr. Martin Huber of Condesys Consulting who is responsible for the online web-based system Koordination im öffentlichen Raum (Spatial, temporal and financial co-ordination of city planning, traffic change, and construction projects on public land) of the City of Bern.  This is a primarily a system for coordinating street works that achieves some of the same goals as the 2004 Traffic Management Act in the U.K. It is location aware and enables planners to avoid serial excavations of the same stretch of street or road by coodinating all construction from multiple agencies including Federal, Kantonal and city street and highway agencies, water/wastewater, gas, and electricity utiltiies, and telecommunications companies so that a section of street or road is not dug up more than once every five years.

The City of Bern typically spends between SFR 80 and 200 million annually on construction for public infrastructure.  The initial phase of the coordination system cost about SFR 150,000.  In its first year of operation it was estimated that the coordination system saved SFR 7 million.  In other words the project paid for itself in about a week.

In 1999 regulations were passed by the city government requiring coordination among stakeholders involved with public infrastructure. Basically the bylaw specified that all excavation on public property   within city limits required a permit.  Stakeholders include the city electric and water utility (Energie Wasser Bern or EWB), Swisscom, UPC Cablecom, Colt Telecom, two railways (SBB and BLS), the Postauto bus system, billboard advertising companies, environmental agencies, archaeological agency, the agency responsible fro public monuments, the garbage collection department, fire, police and emergency agencies, Kantonal public works, and the Federal Highways Agency (Bundesamt für Strassen or ASTRA).  What this means in practice is that all projects involving a certain road or stretch of highway are coordinated so that they all happen at the same time.  After completion of construction there is a moratorium on any further excavations on the same stretch of street or road, except for emergencies, for five years.  It also means that everyone who is affected by street work from garbage collection to billboards to city planners is aware of when and where construction will occur.

The initial implementation of the system, developed by Condesys, was deployed in 2000.  In 2001 it received an award from Arthur Anderson for best egovernment application.

Geolocating underground infrastructure

In Bern the law requires that anyone planning a construction project involving excavation has to submit information about the proposed constrcution to the online coordinaton system.  Providing reliable information about the location of underground infrastructure is the responsibility of the organizations operating the infrastructure.

In Switzerland each utility and telecommunications company is responsible for maintaining records that show the location of their underground infrastructure.  In Bern they are required to provide the location of their underground facilities to the City Survey Office (Vermessungsamt der Stadt Bern ) who is responsible for aggregating the data from the multiple utiltiies and telecommunication companies into a single database (Leitungskadaster) and making it publicly available. 

As in many parts of the world the data quality of this underground geolocation information (Leitungskadaster) is an issue.  According to Martin utilities and telecoms are currently working to improve the quality of their geolocation infrmation about underground facilities.  Swisscom is spending about SFR 250 million to resurvey their infrastructure and other utilties have similar projects underway.  By the end of 2014 EWB and Swisscom are expected to have improved the reliability of their geolocation information about their underground infrastructure in Bern.

The city has also put in place regulations to ensure that accurate data is captured for new construction projects involving underground infrastructure.  For example, there is a 24 hour rule that requires a contractor to notify the city survey department 24 hours before closing a trench.  For large projects city surveyors periodically survey underground works.

Are APIs copyrightable ?

Last week U.S. Court of Appeals for the Federal Circuit in Washington DC ruled that Oracle can copyright application programming interfaces (APIs) for the Java programming language.  In a unanimous ruling the appeals court held that a district judge in California erred in 2012 by declaring that the APIs were simply a function or an idea, and not an expression subject to copyright protection.  The appeals court found instead that, despite the fact Google had written its own code to implement the software, it had infringed copyright by using Oracle’s headers (declarations).  According to one of Oracle's lawyers "Google copied 7,000 lines of code and the structure and organization of whole packages of highly creative software. To say that this is protected is not the same as saying that anything that might loosely be called an API is protectable under copyright law."

Geospatial World Forum 2014 wrapup: Connecting the geospatial industry with mainstream industry

Geospatial World Forum 2014 in Geneva this year had ministerial-level participation from Ghana, Mauritius, Malaysia, India, Azerbaijan and Philippines.  A total of 1,002 delegates from 78 countries attended the conference, as well as 48 exhibitors from 16 countries, including two country-pavilions.  There were 405 technical presentations.

This year's conference had a strong vertical focus and included streams on LIS for Smart Cities, Agriculture, Building and construction, Collaborative approach fostering global peace and prosperity, SDI and urban planning,  Disaster management and planning, Energy, Community engagement, and Climate change.  As an example, I chaired the full day, very well attended Building and construction (GeoBuild) stream which included 15 presentations on both buildings and infrastructure and wrapped up with a panel discussion on vertical and horizontal building information modeling (BIM) with Peter Hansford, UK Government Chief Construction Advisor, Dr Anne Kemp, Director of BIM Strategy and Development at Atkins Global, Hakan Engman, CEO of Agency9, and Andrew Evans, Senior Manager Global Operations at Topcon. 

In addition there were streams with a technical focus including Emerging and disruptive technologies, Space technologies, Big data, Sensors, Business intelligence, Innovative remote sensing and ROI, Open Data, and Cloud computing.

Geospatial Media and Communications honoured the best works and minds of the industry by conferring 14 excellence awards, 10 leadership awards, 5 policy awards and 8 innovation awards.

The awards jury, comprised of Prof. Fraser Taylor, Distinguished Research Professor at Carleton University; Aida Opoku Mensah, Director, ICT, Science and Technology Division at the United Nations; Matt O'Connell, President of MOC Partners; Prof. Henk Scholten, CEO of Geodan and Scientific Director of the SPINlab at the Vrije Universiteit Amsterdam; and David Schell, Chairman of the Open Geospatial Consortium.

- See more at: http://geospatialworld.net/News/View.aspx?id=28999_Article#sthash.Nkn07ued.dpuf

Geospatial Media and Communications honoured the best works and minds of the industry by conferring 14 excellence awards, 10 leadership awards, 5 policy awards and 8 innovation awards.  The awards jury was comprised of Prof. Fraser Taylor, Distinguished Research Professor at Carleton University; Aida Opoku Mensah, Director, ICT, Science and Technology Division at the United Nations; Matt O'Connell, President of MOC Partners; Prof. Henk Scholten, CEO of Geodan and Scientific Director of the SPINlab at the Vrije Universiteit Amsterdam; and David Schell, Chairman of the Open Geospatial Consortium.

At the heavily attended closing panel on the last day of the conference, chair and moderator Christopher Barlow, Director, Strategic Relations and Communications, Thompson Reuters, summed up four days’ takeaways and invited the closing panellists to put their views forward.

Geoff Zeiss, Editor – Building and Energy, Geospatial Media & Communications, Canada, said the strategy to get into verticals such as building & construction, agriculture, energy etc. was an excellent move as it connects the geospatial industry with the mainstream industry and builds awareness about the evolving technologies.

Barbara Ryan, Director, Group on Earth Observations (GEO) Secretariat, Switzerland, said the conference was a perfect way for her organisation, which is pioneering the task of spreading awareness about the use of earth observation data for global benefits, to connect with the private industry, including geospatial and mainstream businesses. GEO also used the forum to launch their pet project GEO Appathon — an app-building contest using EO data.

Prashant Shukhle, Director General, Canada Centre for Mapping and Earth Observation, earth Sciences Sector, Natural Resources, Canada, said the conferences like this was essential is increasing the outreach of geotechnologies. He also called for strong interaction of the public sector with the private players to create conducive policies and market while optimising the use of these innovative technologies. Shukle, however, had a word of warning regarding too fast and too enthusiastic a focus on vertical industries, saying timing is critical and the industry must carefully learn from experiences.

Ronald van Coevorden, Worldwide Segment Marketing Manager – Geospatial Division, Trimble, said his company had been a strong supporter of such events since that creates a platform to interact with a wide variety of people from various public sectors. He also welcomed the trend of vertical focus of the industry.

Geospatial Media and Communications honoured the best works and minds of the industry by conferring 14 excellence awards, 10 leadership awards, 5 policy awards and 8 innovation awards.

The awards jury, comprised of Prof. Fraser Taylor, Distinguished Research Professor at Carleton University; Aida Opoku Mensah, Director, ICT, Science and Technology Division at the United Nations; Matt O'Connell, President of MOC Partners; Prof. Henk Scholten, CEO of Geodan and Scientific Director of the SPINlab at the Vrije Universiteit Amsterdam; and David Schell, Chairman of the Open Geospatial Consortium.

- See more at: http://geospatialworld.net/News/View.aspx?id=28999_Article#sthash.Nkn07ued.dpuf

Canada's open geospatial data initiative

At the Geospatial World Forum in Geneva, as part of a ministerial panel discussion on government's role in evolving geospatial policy for national and regional development, Prashant Shukle, Director General of the Canada Centre for Mapping and Earth Observation gave an overview of the Canadian Government's plan for open access to federal government geospatial data.

Open data

In July, 2012 Tony Clement, Treasury Board President said that "Data is Canada’s new natural resource…”  It is well-known that spatial information contributes significantly to the Canadian economy, in the range of billions of dollars.   The Canadian Economic Value Study and Sector Scan, which is currently underway and will be completed this Fall, will put a more precise dollar figure on the value of spatial data and technology to the Canadian economy.

But the government recognizes that the true value of geospatial data to the Canadian economy will only be recognized by its liberation and use. Canada has taken a number of steps as part of the Open Government Action Plan 2.0.  It has developed an open government license which removes restrictions on the reuse of all types of data published by the Government of Canada and aligns Canadian policy with international best practices to promote the re-use of Federal data as widely as possible.  It has created an open data portal (data.gc.ca) which houses 191,608 datasets of which 96.5% are geospatial datasets.  In addition it is working toward a pan-Canadian Open Data Strategy.

In June 2013 Prime Minister Steven Harper signed  the G8 Open Data Charter, a set of norms and standards for the proactive release of high-quality data that is usable by all and is unrestricted in its use and re-use.  All of this reflects a data policy where government data is published openly by default, not as the exception.

Sharing data within government 

The new open data policy is helping the Canadian Government to transform itself.  The Government's Blueprint 2020 aims at encouraging open and networked, engaged citizens through policies and standards including standards for geospatial data, a standard for metadata, and shared services.

Within the federal govenment there is a growing need for geospatial data.  In a FCGEO survey of federal departments in May 2012 94% of respondents reported increasing demand for and use of geospatially-related data to meet business requirements.  21 federal departments rely on geospatial data related to weather, resource development, endangered species, national parks, national defense, census data, public health and oceans management, and other topics.  The challenge is to enable easy discovery and access to all federal government data holdings. 

In 2012 the Government of Canada created the Federal Committee on Geomatics and Earth Observation (FCGEO) to work toward a whole of government, enterprise solution for geospatial and Earth observation data.

One of the FCGEO's important initiatives is the Federal Geospatial Platform (FGP), which is intended to be a common “platform” of technical infrastructure, policies, standards and governance that will open up  the government’s massive storehouse of geodata and imagery for new and innovative uses. This integrated national system is intended to reduce unnecessary duplication, fragmentation and overlap of geospatial services.  Currently it can take weeks to months to find the data owner, acquire and manipulate the data, conduct the analysis and generate reports.   The FGP is intended to enable users to “search once and find everything” within the federal government’s geospatial data and information holdings and reduce the time required to collect data and generate reports to hours.  In addition the FGP’s visualization tools and analytics are intended to enable the public, private and academic sectors and individual Canadians to create new value from government data sources.

Korea's BIM on GIS project is developing a platform for spatial interoperability

At the Geospatial World Forum in Geneva, several geospatial-related projects from South Korea are being highlighted.  One of the most important is a five-year project conceived, sponsored and funded by the Korean Institute of Construction Technology (KICT).  The objective of the project, called BIM on GIS Interoperability Open-Platform, is to develop a software platform that enables GIS and BIM interoperability.  The project is being carried out by Korean software company Gaia3D.

Gaia3D has been prototyping a software architecture comprised of application plug-ins, desktop and web clients, 3D BIM/GIS object server, spatial RDBMS, and spatial data including BIM and GIS models.  The main functions that the software platform supports are BIM format conversion (rvt to internal) for improved performance, simultaneous spatial query and analysis for geospatial and BIM data, application APIs for facility management (FM) and energy management, interactive navigation inside and outside of buildings, control over transparency (making walls transparent, for example), and 3D visualization.  It supports large data volumes including BIM, digital terrain models, orthoimagery, photorealistic 3D visualization, textures, augmented reality, both BIM and GIS models and international standards IFC and CityGML.  The application is intended to be vendor neutral with respect to both BIM and GIS vendors.

The current prototype relies on open source geospatial software including GeoServer, World Wind SDK for Java, OpenLayers, and PostGIS.

An example that was demonstrated to me at Geospatial World Forum by Heegu Park of Gaia3D was KOPRI (Korea Polar Research Institute), who maintain a research station called King Sejong in Antarctica.  BIM models were developed for the 35 buildings of the research station and integrated with geospatial data including a digital terrain model and satellite imagery.  Navigation inside and outside of buildings was demonstrated, looking outide through windows, as well as removal of walls and rooves to visualize inside infrastructure.

Classifying geolocation information about subsurface utilities

I've blogged several times about the expanding effort in Europe and the United States to map accurately underground infrastructure.  I blogged about the high ROI for investment in improving the geolocation and other information about underground utilities, the project of the City of Las Vegas to create a 3D model of its underground utilities and a ten year effort in Lombardy, which includes Milan, to map all underground infrastructure using ground penetrating radar (GPR).

At the SPAR International conference Steven DiBenedetto, Senior Geoscientist & Technology Manager at Underground Imaging Technologies, whose field is geophysics and how it relates to subsurface utility engineering (SUE), compared using GPR for detecting underground and other hidden infrastructure with laser scanning of above ground structures.  In addition to underground utilities, GPR can be used to detect rebar.  BIM models makes it possible for rebar detailing to be a fully realized component of a structural design.  GPR can be used to detect existing rebar embedded in concrete.

 I've blogged previously about level of development (LoD) in the context of BIM modeling for buildings and horizontal infrastructure. 

• 100 – generic representation
• 200 – generic representation; approximate quantities, size, shape, location, & orientation
• 300 – specific system object or assembly
• 350 – Include interfaces to other building systems
• 400 – include detailing, fabrication, assembly, & installation information
• 500 – field verified

LOD relates to the degree of detail included in a model element and is (mostly) based on objects that are visible, at least during construction.  Steven sees a parallel between LoD and the ASCE Standard 38-02 "Standard Guideline for the Collection and Depiction of Existing Subsurface Utility Data"

• Quality Level D (QL D) Review of Existing Records & Information
• Quality Level C (QL C) Surveying & plotting above ground (surficial) features and connecting points
• Quality Level B (QL B) Surface geophysical methods to map subsurface utilities
• Quality Level A (QL A) Non-destructive excavation to expose & survey subsurface utilities, typically by potholing

The SUE classification is based on classifying the reliability of the location about subsurface facilities depending on the means by which the subsurface infoormation was obtained.  For example, a pipe can be represented as

• line
• line with dimension and colour representing type of pipe
• cylinder with accurate diameter
• pipe assembly with accurate dimension, location and other metadata

Perhaps the most important thing that LoD and ASCE quality level for SUE have in common is they  measure reliability, the degree to which you can rely on the information.

There are significant differences between the technologies that are used for above ground laser scanning and subsurface scanning with GPR and the interpretation of the results.  Laser scanning typically involves very short wavelengths which makes possible high resolution, on the order of millimeters.  The media in which it operates is air, which is relatively homogeneous and non-absorbing at the wavelengths that are used.  This means that laser scanning can record accurately at distances of up to hundreds of meters from the target. Lase scanning requires optical line-of-sight visibility.  Measurements can be easily ground truthed by tape measure or total station.  The result is a point cloud that can be visualized and measured and compared directly with the scanned object.  In some cases feature extraction techniques can be used to extract individual objects to form a 3D model of the scanned object.

The wavelengths used in GPR are longer, sub-meter wavelengths,  to enable them to pass through soil and rock  which limits the spatial resolution that is achievable.  The medium is heterogeneous - it may be comprised of different soil and rock types together with manmade materials.  The sensor must be relatively close to the object, typically within meters or even feet depending on the medium and the strength of the transmitter.  Transmitters in Europe are permitted to be stronger than in the U.S. where the FCC severely limits transmitter power.  As with any type of radar, GPR signals must be interpreted.  It is difficult to ground truth what has been detected without potholing - actually digging a hole.  In Steven's experience with GPR you use all other available information including existing engineering drawings, above ground visible structures such as manholes and storm drains, and historical records.