Between the Poles

Be Inspired Awards 2016 reveal rapid adoption of reality capture in construction

At the Year in Infrastructure 2016 conference in London the Be Inspired Awards set some new records. There were 311 submissions from 22 countries.  Of these 110 were completed and operational projects and 120 were under construction.  60 projects were chosen as finalists in 18 categories including asset performance, power generation, rail and transit, mining, roads, utilities and communications, water network analysis, and construction.

15 of the 60 finalists reported using reality capture which is evidence of remarkably rapid adoption since Bentley only acquired a reality capture capability (Acute 3D since renamed as ContextCapture) in February of last year.  At this year's event Bentley announced that ContextCapture can now process LiDAR point clouds.

Development of an open spatially-enabled BIM query language

Introduction

Building Information Models are comprehensive digital representations of buildings which include 3D geometry and associated data. They are widely used for designing, engineering, and constructing buildings (vertical BIM) and infrastructure (horizontal BIM). Owners are beginning to see value in BIM models and data for operating buildings. A BIM model includes not just the 3D geometry of all building elements and the enclosed spaces, but also semantic information representing both the type of the elements, the relationships between them (defined by the data model) and data associated with the geometric elements.  With BIM models being mandated in countries like the UK, Finland and Singapore, and in France and Russia in the near future,  and the increasing adoption of BIM by the private sector in the U.S. and other countries, the volume of BIM data is growing rapidly.  By merging models from different disciplines into common virtual models, the amount of information stored in such multidomain repositories quickly becomes large and complex even for average projects.  Centralized or distributed repositories enable the creation, integration and maintenance of large quantities of data from various stakeholders involved in the planning and building process and the wide range of specialized software tools used by these stakeholders.  Many ways of creating, manipulating and visualizing BIM and CAD models have been developed including CAD, Solibri, Navisworks, GTPPM, mvdXML, PQML, EQL, SQL, XSLT/XQuery, SPARQL, Gremlin, Linq, SDAI, and generic programming languages.  However, the development of a general, intuitive query language for BIM models including geometric and related information remains a challenge.

The information needs of individual stakeholders in different parts of the construction process are very different. For example, a structural engineer does not require all the information available in the overall building model such as the detailed specifications of a suspended ceiling. This makes the extraction of partial model subsets or domain specific views on large models necessary.  In addition regulations, energy performance modeling, and building maintenance require finding specific facilities among the building assets. 

In the last few years research has focussed on the development of an open, domain-specific query language for BIM.   Most of the this research has focussed on querying, updating and deleting data stored in Industry Foundation Classes (IFC) models.  The Industry Foundation Classes (IFC) is a vendor neutral and open model that defines more than 650 entities and a few thousand attributes.  Most industry software BIM tools  are able to export IFC models, though there is typically some information loss. The bimserver.org platform is an open repository of IFC models and already provides a Java API to extract partial building information models from a repository.

Open query languages

Many existing database applications use the Structured Query Language (SQL), an ANSI/ISO standard with spatial extensions standardized by the Open Geospatial Consortium (OGC), as the standard language. SQL makes it possible to create, read, update and delete records in a Relational Database Management System (RDBMS).  But the applicability of SQL in a BIM context is limited.  SQL is based on operations on data stored in tables.  Application to IFC, as a BIM example, would require storing 600 entities along with their thousands of attributes in individual tables.  Severe performance and scalability issues are associated with using SQL for BIM.  In addition the complexity of IFC-based queries would rapidly become too complex.

The W3C Data Activity has defined a collection of technologies comprising a “web of data” where information is easily shared and reused across applications.  Key parts of this technology stack are the RDF (Resource Description Framework) data model, the OWL Web Ontology Language and the SPARQL protocol and RDF query language which has been standardized by the W3C.  The Resource Description Framework (RDF) is a directed, labeled graph data format for representing information on the Web.  RDF and SPARQL  enables interoperability among distributed heterogeneous information systems making possible queries that span several repositories and link information from different sources.  Specifically in a BIM context it enables ad hoc queries of sub models that reside in repositories maintained by the different stakeholders in a building project.

Spatial queries

BIM data models can be simple or complex.  A complex data model includes logical relationships between building elements, such as windows and walls, walls and storeys, and so on.  These relationships are created at design time.  A simple model may not include any explicit relationships. For example, there may not be any way to determine which windows are associated with a wall except visually.  Spatial queries enables relationships to be determined after the creation of the BIM model.  For example, a spatial query can find all the windows in a wall, all the walls of a storey, or all the HVAC and plumbing facilities in a storey.

The efficient implementation of spatial BIM queries requires 3D spatial indexing such as octree and multi-dimensional r-tree indexes and algorithms.  It has been known for a long time that spatial indexing is a key technology enabling efficient GIS systems.  Very early on in the development of spatial indexes it was realized that these are domain specific.  Several GIS systems support an extended spatial SQL based on quadtree or r-tree indexes.  These systems evolved historically from a 2D geometric representation approach.  However, the functionality for processing 3D geometry in many GIS systems is restricted and the performance of the available tools is unsuitable for complex building data sets.  Therefore, it has been argued that a specialized tool is required to handle queries against elaborated BIM models containing vast numbers of elements and detailed geometry representations.  Such a query language enables the spatial analysis of BIM models and the extraction of partial models that fulfill certain spatial constraints. Among other features, it includes operators that reflect the topological relationships between 3D spatial objects including "within", "contain", "touch", "overlap", "disjoint" and "equal" in 3D space.  Both octrees and multi-dimensional r-tree indexes have been investigated as a basis for an efficient BIM query language.

Open BIM query language

A BIM query language, dubbed BIMQL, has been proposed as an extendable, open, domain specific query language for BIM models. It can be used to select and update partial aspects in building information models.  A limited implementation of the language has been built on top of the bimserver.org platform.  It is not complete, in particular it does not support spatial queries, but has provided a useful vantage point for future research, discussion and development on the development for end-user interfaces to complex BIM models as well as the composition of service-oriented architectures.

Unlike traditional data modeling approaches which are limited by the scope of their underlying schemas, RDF and related technologies can provide an open and common environment for sharing, integrating and linking data from different domains and data sources.  In comparison with domain-specific query languages, SPARQL is especially applicable for scenarios when data from multiple sources are needed.  Some important scenarios include

• All building objects should be classified according to the local building code
• Where are the locations of companies which produce the materials used in walls placed in the hall ?

The interesting thing about these scenarios is that they require the BIM geometry and data plus other external data. This is the type of query that the W3C semantic web technologies are designed to support.

In the AEC domain, a typical use case is data integrity validation against BIM standards or building code requirements.  A Dutch example is the Dutch BIM standard requires that all building elements should be associated with appropriate building storey.  Provided that the building model is represented in the standardized ifcOWL, it is possible to check this spatial containment relationship using off-the-shelf SPARQL implementation.

Currently SPARQL does not contain the vocabularies or functions required by many use cases in the construction domain.  Recently researchers have proposed extending SPARQL with a set of domain-specific functions for the construction world. There are precedents for this strategy.  In 2011 the Open Geospatial Consortium (OGC) released GeoSPARQL, a geographic query language for RDF data, which extended SPARQL with geospatial functions that enabled spatial queries.  The advantages of this approach is that not only are the extended AEC functions compatible with existing SPARQL environments, but they can also be used to query building data combined with data from other fields.

But standard SPARQL can only crawl the data graph according to the structure of the BIM data model.  There are many use cases that depend on geometric relationships that cannot be handled by off-the-shelf SPARQL. To address this SPARQL has been extended to include spatial operators "touches", "intersects", "disjoints", and "contains" and well as other domain-specific functions.

An example of a simple spatial query using a spatial extension is finding all walls which contain or adjoin doors.  This requires the spatial function "touches" to find doors that are in or near walls.

As in the case of geospatial data, additional domain-specific functions are required to provide the necessary functionality.  For example, functions were added for different ways of measuring distance (spt: defines the spatial extensions namespace)

• spt:distance is a function to return the shortest distance between two products in 3D space.
• spt:distanceZ is a function to return the shortest vertical distance between two products.
• spt:distanceXY shortest distance between the projections of two products on XY plane

Another example is finding all windows that are close (less than 300 units) to a column.

Implementation and testing

As a proof of concept, the extensions were implemented
based on the open source Jena ARQ query engine.  An objective was to try to  minimize low level coding to make the function implementations more portable and more transparent for public reviews.

As a practical example, a case study of building code compliance checking using the International Building Code 705.8.4 (IBC 2006) was tested successfully using a BIM model of a building with 4 floors.

The researchers report that the main limitations of the open SPARQL-based approach they have proposed relate to the way it was implemented.  The implementation is not completely portable and performance could be improved, by integrating existing geometric libraries, for example.   Future research will address these issues and investigate more use cases to extend functions for specific domains and to combine more data from different sources in the construction industry.

Sources

Querying Linked Building Data Using SPARQL with Functional Extensions, 2016, Chi Zhang and Jakob Beetz

Processing of Topological BIM Queries using Boundary Representation Based Methods, Simon Daum and André Borrmann, Advanced Engineering Informatics, Volume 28, Issue 4, October 2014, Pages 272–286

BIMQL – An open query language for building information models, W. Mazairac and J. Beetz, Adv. Eng. Informat. (2013)

Topological analysis of 3D building models using a spatial query language, André Borrmann and Ernst Rank, Advanced Engineering Informatics 23(4):370-385 · October 2009

Thanks to Léon van Berlo of TNO for pointing me to this research.

Featured presentation at "Year in Infrastructure": Buried Utilities Management

 

2 November 14:30 - 15:30

Dr. Anne Kemp
Atkins Fellow and Director, Atkins



Dr. Nicole Metje
Reader in Infrastructure Monitoring, University of Birmingham (UK)


“Out of site and out of mind.” Many of the challenges faced by utilities in managing and operating buried infrastructure are encapsulated in this phrase. This session explores how software and technology can make our buried infrastructure more visible to all stakeholders in a utility – from engineers and maintenance crews ensuring assets deliver a required level of service to customers, through to planners and financial controllers responsible for delivering budgets and regulatory compliance.

Year In Infrastructure (London) Utilities

Efficient low cost nano-scale catalyst directly converts CO2 to ethanol

Many commodity products are manufactured from organic compounds sourced originally from fossil fuels. Closing the carbon cycle by utilizing CO2 and displacing fossil fuels as a source (feedstock) for these commodities is a key intermediate step towards a carbon-free future. Direct electrochemical conversion of CO2 to useful products has been under investigation for a few decades. Recently the Department of Energy’s Oak Ridge National Laboratory has developed an electrochemical process that uses nanometer scale spikes of carbon and copper to turn carbon dioxide into ethanol. A catalyst made of carbon, copper and nitrogen and applied voltage triggers a complicated chemical reaction that runs at room temperature and converts a solution of carbon dioxide dissolved in water into ethanol with a yield of 63 percent. The catalyst is a nanoscale structure, consisting of copper nanoparticles embedded in carbon spikes (Image: copper nanoparticles with a diameter of about 50 nm seen as spheres embedded in carbon nanospikes). The nano-texturing approach is low cost because it avoids the use of expensive or rare metals and operates at room temperature in water. It is believed the process can be scaled up for industrially relevant applications. High-Selectivity Electrochemical Conversion of CO2 to Ethanol using a Copper Nanoparticle/N-Doped Graphene Electrode, Yang Song, Rui Peng, Dale K. Hensley, Peter V. Bonnesen, Liangbo Liang, Zili Wu, Harry M. Meyer III, Miaofang Chi, Cheng Ma, Bobby G. Sumpter, Adam J. Rondinone, ChemistrySelect, 28 September 2016, DOI: 10.1002/slct.201601169

International agreement to reduce greenhouse gases hydrofluorocarbons emissions

200 countries have agreed in Kigali to reduce the emissions of hydrofluorocarbons (HFCs). HFCs are greenhouse gases used as an alternative to ozone-depleting chlorofluorocarbons (CFCs) in foam production, refrigeration, and air conditioning. When it was realized that chlorofluorocarbons were responsible for the ozone hole over Antarctica, nations got together in Montreal in 1987 and agreed to stop using CFCs. CFCs were replaced by hydrofluorocarbons for refrigeration and other applications and their use has been increasing by 10% per year. However, it was realized that HFCs are far more potent than CO2 in trapping heat and they have a lifetime of 14 years in the atmosphere. The Kigali agreement is an amendment to the Montreal Protocol on Substances that Deplete the Ozone Layer. The rapid growth of HFCs in recent years has been driven by a growing demand for cooling, particularly in developing countries with a growing middle class and hot climates. The Kigali amendment provides for exemptions for countries with high ambient temperatures to reduce use of HFCs at a slower pace. It is estimated that phasing out HFCs could prevent up to 0.5 degrees Celsius of global warming by the end of this century. UNEP Countries agree to curb powerful greenhouse gases in largest climate breakthrough since Paris

Global methane emissions 60 to 110 % greater than current estimates

Methane has the second-largest global radiative forcing impact of anthropogenic greenhouse gases after carbon dioxide. In addition to anthropogenic sources, mainly fossil fuels, livestock and waste, natural methane sources include the biosphere (wetlands, termites, oceans, wildfires, and wild animals), volcanoes and geothermal emissions, and geological seepage where large quantities of natural gas migrate from shallow or deep rocks and reservoirs to the surface along faults and fractured rocks.

Estimates of emissions have come under increasing scrutiny. A recent study assessed the spatial distribution of anthropogenic methane sources in the United States by combining comprehensive atmospheric methane observations, extensive spatial datasets, and a high-resolution atmospheric transport model. It was concluded that the US Environmental Protection Agency (EPA) underestimates methane emissions nationally by a factor of 1.5.

The concentration of methane in the atmosphere stabilized from about 1999 to 2007.  But here is evidence that since 2007 it began rising again.  A recent study suggests that the more than 30% increase in U.S. methane emissions over the 2002–2014 period could account for 30–60% of the global growth of atmospheric methane seen in the past decade.

In a study just published the global methane budget and the contribution of the fossil fuel industry to methane emissions has been reevaluated. The ratio of carbon-13 to carbon-12 provides a signature which helps identify the source of methane. Both global methane and methane carbon isotope (carbon-13) records were used to compile what is believed to be the largest isotopic methane source signature database, including fossil fuel, microbial and biomass-burning methane emission sources. Total fossil fuel methane emissions from the fossil fuel industry plus natural geological seepage are 60 to 110 % greater than current estimates. After accounting for natural geological seepage, it is found that methane emissions from natural gas, oil and coal production and their usage are 20 to 60 % greater than current estimates.

Next generation weather satellite will support nowcasting

As the electric power industry generates increasing amounts of renewable energy from intermittent sources such as wind and solar PV, the ability to nowcast radiance and wind velocity with km resolution up to 25 minutes in advance has become essential to balancing electricity demand and supply.  This is the newest area where geospatial technology (wind at different altitudes, radiance, and temperature mapping) November 4 of this year NOAA and NASA will launch the GOES-R geostationary weather satellite which will provide support for nowcasting across the continental U.S..

GOES-R's Advanced Baseline Imager (ABI) will collect three times more data and provide four times better resolution and more than five times faster coverage than current GOES. The GOES-R series satellites will also carry the first lightning mapper flown from geostationary orbit. The Geostationary Lightning Mapper, or GLM, will map total lightning (in-cloud and cloud-to-ground) continuously over the Americas and adjacent ocean regions.  GOES-R will provide coverage over a 1000x1000km box with a temporal resolution of 30 seconds, and spatial resolution of 0.5 to 2 km. It will completely scan the continental U.S. every 5 minutes, providing coverage of the 5000km (E/W) and 3000km (N/S) rectangle over the United States.

The Advanced Baseline Imager (ABI) supports a wide range of capabilities relating to weather nowcasting and climate monitoring including aerosol detection and measurement, including smoke and dust, clear sky masks, properties of clouds and moisture, downward shortwave radiation,  fire/hot spot characterization, hurricane intensity estimation, land surface temperature, radiances, rainfall rate, reflected shortwave radiation, sea surface temperature, snow cover, total precipitable water, and volcanic ash properties.

GEOS-R enables “nowcasting” of severe storms across the continental United States. GOES-R will fly the first operational lightning mapper flown in geostationary orbit.  It will cover land and oceans. Total lightning (in-cloud, cloud-to-cloud, and cloud-to-ground) information from GOES-R will increase lead time for severe storm warnings because it will make it possible to observe areas of severe weather every 30-60 seconds. This will enable more reliable warnings and evacuations.

Transactive energy may be based on blockchain

There is little doubt that "transactive energy" is in the future of electric power in North America, which already has continental grids, and in the EU with the development of the EU's supergrid.  The world is rapidly developing the technology that allows energy flows to be  determined by market forces (transactive energy).   By analogy with Uber and Airbnb, Gartner has predicted that by 2020, the largest energy company in the world (by market cap) will not own any network (grid) or generation assets.  It will manage information about energy sources and consumers.  Another option is a decentralized,distributed transaction system that allows generators such as you and I as well as traditional large scale utility generators to sell energy to you and me and other users, but without a centralized transaction manager.

Blockchain is a decentralized, distributed database for managing transactions.  Blockchains provide a global infrastructure untethered from the stability or permission of governments and institutions.  It is the technology underlying Bitcoin. The generalized version is often referred to as blockcoin 2.0.  Blockchain supports smart contracts.  Nasdaq and other financial institutions including banks have been experimenting with and developing applications based on blockchain technology. Nasdaq has opened its blockchain services framework to more than 100 of its market operator clients around the world. The blockchain services are part of what Nasdaq calls its "Core Services" component which serves as a hub for its financial applications.  Late last year an issuer was able to use Nasdaq Linq blockchain technology to successfully complete and record a private securities transaction - the first of its kind using blockchain technology.  Chain.com, a Nasdaq Linq client and blockchain developer, documented its issuance of shares to a private investor using Nasdaq's blockchain-enabled technology.

Earlier this year Nasdaq demonstrated a blockchain service that lets solar power generators sell energy certificates (Nasdaq Explores How Blockchain Could Fuel Solar Energy Market).  The project is part of a collaborative effort between Nasdaq and design firm IDEO's CoLab to facilitate partnerships that take a design-based approach to creating human-usable technology.  Internet connected solar panels have been developed with technology provided by Filament , a Nevada-based blockchain startup. Its technology allows traditional electronic devices to be connected online.  The solar panel is actually hard-wired into the IoT device through a converter which enables Nasdaq to measure the wattage the panels are generating into the grid.  Using the API of Nasdaq's blockchain-based private markets platform, anonymous certificates are created which can be sold to anyone who wishes to subsidize solar energy.  The cryptographically verified certificate, representing solar power generated in the western US, appeared live on the screen in New York City.

Nasdaq is not the only organization exploring blockchain for energy transactions.  Brooklyn-based startup LO3 has partnered with Consensus Systems on TransActive Grid which is combination of ​software ​and hardware ​that enables members to buy and sell energy from each other securely and automatically, using smart contracts and the blockchain.

In Vienna, Grid Singularity is using blockchain to support energy-related transactions. "Damit haben wir (fast) alles beisammen, was in der neuen Energiewelt relevant ist oder kurzfristig wird: dezentrale Energieversorgung, Digitalisierung, disruptive Geschäftsmodelle, Smart Contracts, Blockchain, Kryptowährung.  Als Wegweiser in die neue Energiewelt, haben wir am 23. Mai 2016 den 1. Blockchain-Tag in Deutschland veranstaltet." (We've just about got everything we need for the new energy world, decentralized energy distribution, digitization, disruptive business model, smart contracts, blockchain, and cryptographic security.  As a signpost to the new energy world, we have instituted May 23, 2016 as the first Blockchain Day in Germany.)

Australian startup Sun Exchange has developed a platform that lets investors back small-scale solar projects and receive monthly dividends. 

MIT start-up SolarCoin (SolarChange in the US and EU) pays people with an alternative digital currency for generating solar energy.  SolarCoin is based on Bitcoin technology.  The original concept for SolarCoin required a central bank. Blockchain is decentralized making the central bank unnecessary.  People earn coins as a reward for generating solar energy.  People with solar panels on their house receive solar renewable energy certificates from their energy company in return for feeding a megawatt-hour of electricity back into the grid. These certificates are already traded for cash, but if you present them to SolarCoin you will get a coin. SolarCoins are now given in 23 countries. The SolarCoin market cap is currently estimated to be about $2 million.

Crowd behaviour modeling with BIM

I spent a fascinating day at the CanBIM Regional Session & Technology Exhibition in Toronto.  I was very impressed by how much things relating to BIM have progressed in Canada, which has generally lagged the countries spearheading BIM development, partly because of government inaction.

One of the most interesting presentations today was by Erin Morrow of Arup who talked about two pedestrian simulation products he has been responsible for developing, MassMotion and Flow.   These are 3D agent-based models.  They are based on real spaces with continuously connected 3D geometry and crowd interactions.  Agents have size and acceleration, personalities that prefer things like avoiding going up stairs.  They can dynamically assesses their environment and make routing decisions.  Social forces determine how agents respond to their environment, other people, and goals.  They try very hard not to hit obstacles or bump other agents.  Agents are able to make autonomous decisions based on this continuous space.  For example, MassMotion can simulate how agents will be behave when faced with a choice between a crowded elevator or empty stairs. 

There are also tools for assessing the result of a simulation including 3D dynamic visualization and various quantitative metrics such as density in various parts of the model, how long it takes people to get from one point to another, what route do most people take, flow rates through doors and up escalators, and and others.

The simulation tool defines portals, where people can enter or leave from, spaces where agents can go anywhere, connectors that connect rooms and other features.  Erin demonstrated live how to create a simple model with two rooms, connected by a door, with a portal where people entered and an exit portal.  He created a simulation where 100 people enter the first room every minute and visualized the crowd flow in 3D.  It was fascinating to watch how people bunched in front of one of the connecting doors and then the other.

The simulation geometry can be developed from scratch in MassMotion.  But for complex structures it is much simpler to import a BIM model (MassMotion imports IFC models from a variety of software including AutoCAD, Microstation, SketchUp, Rhino, and Revit. ) to create spaces and connectors including stairs and escalators.  Erin demonstrated doing this with a BIM model of an airport.  MassMotion was able to correctly identify 90% of the elements it recognizes such as rooms, doors, stairs and escalators.  In the demonstration some editing was required to make sure there was a continuous geometry.  For example, an escalator needed editing to logically connect to the upstairs floor. Then the user adds other information such as portals, sources where people come from, sinks where people go and rates of flow through the portals people enter from.  People may come from outdoors or train cars and they may be going to gates to catch planes.

The software has roles to play during design, during construction, and as a management tool throughout the lifespan of a building and surrounding areas.  It can be used operationally during construction to design alternate routes during construction.  The software was used to simulate passenger movements during a full day at the new Jetblue T5 terminal at JFK airport in New York with the objective of ensuring passenger comfort and fluidity of motion in the terminal.

There are many other applications used by engineers and planners including evacuation analysis.  One of the interesting results that Erin mentioned was that the Roman Coliseum built in 70 CE could be evacuated in 15 minutes, the same time it is estimated it takes to evacuate the recently built Olympic stadium (the Bird's Nest) in Beijing.

Autodesk utility design and substation products spun off to SBS

It has just been announced that Autodesk and Spatial Business Systems (SBS) have formed a strategic alliance.   SBS will be responsible for future development, support, and licensing of Autodesk^® Substation Design for Inventor^®, Autodesk^® Substation Design for Electrical, and AutoCAD ^® Utility Design (AUD) software.   SBS will focus on the ongoing development and support of Substation Design and AUD, while Autodesk will continue to focus on the underlying platform technologies. This is intended to enable SBS to employ innovative, customer-focused development processes to support the new product enhancements necessary to address the evolving needs of the utility industry. The new products offered by SBS will be renamed to reflect the new structure.

The Autodesk team responsible for product development, system deployment and support will join SBS and work to incorporate new enhancements that will more closely integrate with the SBS Utility DataHub™ suite of utility integration products.

This sounds like very good news for Autodesk utility customers.  I have known Dennis Beck, President of SBS, for years.  He and his team know the utility business intimately having developed spatially-enabled utility solutions integrating Smallworld, Autodesk, Oracle and other products for a wide range of utility customers.