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Journal Paper Accepted at the Journal of Intelligent Manufacturing: Measures of reconfigurability and its key characteristics in intelligent manufacturing systems

The LIINES is pleased to announce that the Journal of Intelligent Manufacturing has accepted our paper entitled: “Measures of reconfigurability and its key characteristics in intelligent manufacturing systems”. The paper is authored by Amro M. Farid and was published in October 2014.

Many manufacturing challenges arise with the global trend of increased competition in the marketplace.  Production processes must deal with shorter product lifecycles and mass-customization. Consequently, production systems need to be quickly and incrementally adjusted to meet the ever-changing products. Reconfigurable manufacturing systems have been proposed as a solution that facilitates changing production processes for highly automated production facilities.

Much research has been done in the field of reconfigurable manufacturing systems. Topics include: modular machine tools and material handlers, distributed automation, artificially intelligent paradigms, and holonic manufacturing systems.  While these technological advances have demonstrated robust operation and been qualitatively successful in achieving reconfigurability, there has been comparatively little attention devoted to quantitative design methodologies of these reconfigurable manufacturing systems and their ultimate industrial adoption remains limited.

Measuring reconfigurability of manufacturing systems quantitatively has been a major challenge in the past, since a quantitative reconfigurability measurement process was non-existent. Earlier work developed a measurement method that extracts measurables from the production shop floor. When this was established, basic measures of reconfiguration potential and reconfiguration ease were developed, based on axiomatic design for large flexible engineering systems and the design structure matrix respectively.

Reconfiguration of a production process can be split up in four steps: Decide which configuration, Decouple, Reorganize, and Recouple. The larger the number of elements in the system, the more configurations are made possible. This is measured using the reconfiguration potential measure, based on axiomatic design for large flexible engineering systems.

Production processes contain multiple interfaces within themselves. Multiple layers of control can be distinguished, that have to work together to coordinate the physical components. These interfaces are the main determinants for the reconfiguration ease measure.

This paper combines these techniques to define a quantitative measure for reconfigurability and its key characteristics of integrability, convertibility and customization.    The intention behind this research contribution is that it may be integrated in the future into quantitative design methodologies for reconfigurable manufacturing systems, which may be easily adopted by industrial automation and production companies.

About the author: Wester Schoonenberg completed his B.Sc. in Systems Engineering and Policy Analysis Management at Delft University of Technology in 2014. After his bachelors’ degree, Wester started his M.Sc. at Masdar Institute of Science & Technology. Currently, Wester is working on the integrated operation of electrical grids and production systems with a special interest in the demand side management of industrial facilities.

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LIINES Website: http://amfarid.scripts.mit.edu

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Duke Energy on Analytics and the Internet of Things

It’s been a long time since 2003 when the concept of the Internet of Things was first proposed by U. of Cambridge Auto-ID Laboratory.  At the time, Dr. Amro M. Farid, now head of the Laboratory for Intelligent Integrated Networks of Engineering Systems, was a doctoral student investigating how RFID technology enabled intelligent products within reconfigurable manufacturing systems.  The Internet of Things was being applied primarily in the manufacturing and supply chain domain.

Since then, the Internet of Things concept has taken hold not just in manufacturing systems and supply chains but nearly every industrial system domain including energy.    Every “thing” or “device” has the potential to be connected via an intelligent sensor so as to make decisions — be they centralized within an operations control center — or distributed amongst artificially intelligent multi-agent systems.   The Internet of Things concept has the potential to fundamentally transform industrial systems.

Have a look at Duke Energy’s take on the Internet of Things:

The LIINES is proud to have been working in this area since its inception and continue to do so.  More information on our research can be found on the LIINES website.

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Journal Paper Accepted at ISA Transaction: Event Triggered State Estimation Techniques for Power Systems with Integrated Variable Energy Resources

The LIINES is happy to announce that ISA Transactions has accepted our recent paper entitled: Event Triggered State Estimation Techniques for Power Systems with Integrated Variable Energy Resources.  The paper is authored by Reshma C. Francy, Prof. Amro M. Farid and Prof. Kamal Youcef-Toumi.
In recent years, we have had the opportunity to contribute to two large studies that present visions of the future smart grid:  The MIT Future of the Electric Grid Study, and the IEEE Vision for Smart Grid Controls: 2030 and Beyond.  Both of these works emphasized that in order for the future grid to be truly smart, it has to be responsive, dynamic, adaptive and flexible.  This is the case even when highly variable renewable energy sources sources are plugged in.   The first step in achieving this vision is having greater “situational awareness” — knowing what is going on when and where in the grid.
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For decades, state estimation has been a critical technology in achieving such situational awareness for power system operators.   Over time, it has become quite the mature technology. But, the integration of renewable energy changes all that.  Not only does it introduce rapidly changing behavior into the grid; but it also does so in the low voltage distribution system where state estimation is not usually applied.   The conventional solution is to not just monitor the grid faster but also for the entire power grid all the way down to the low voltages.  That means that not only do all the power grid’s measurements have to be gathered from across power grid’s geography but they also have to computed at an ever faster rate.   This is an exponentially growing problem  — hardly a solution befitting a future “smart” grid.
This paper seeks to address these two requirements in a practical way.   The idea is to use a concept called “event-triggering”.  It takes advantage of the fact that the wind doesn’t always blow and the sun doesn’t always shine.  When local power grid conditions are highly variable, say at a wind turbine or solar panel, a “trigger” will kick in telling the state estimator to run.  But when the power grid is relatively stable, the new state estimator will use a simplified linear approach based upon the last time the full state estimator was run.  Relative to traditional state estimation, this simple solution has been shown to reduce computational time by 90% in numerical case studies.
While ultimately, in the long term, the smart grid will require a fundamental “rethink” in how to approach state estimation, monitoring, and situational awareness, this solution demonstrates how traditional state estimation techniques can be enhanced for future smart grid applications.
A full reference list of smart grid research at LIINES can be found on the LIINES publication page: http://amfarid.scripts.mit.edu

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Prof. Amro M. Farid gives invited lecture at MIT Transportation Seminar Series

On December 5, 2014, Prof. Amro M. Farid gave an invited lecture at the MIT Transportation Seminar Series (Cambridge, MA, USA).   The presentation entitled:  “Intelligent Transportation-Energy Systems for Future Large Scale Deployment of Electrified Transportation” featured the LIINES’ latest research in transportation electrification.

The presentation advocates an integrated approach to transportation and energy management.  At its core, the intelligent transportation energy system (ITES) requires a new transportation electrification assessment methodology that draws upon microscopic traffic simulation, power grid dynamics, and Big Data-Driven use case modeling. Such an ITES would come to include coupled operations management decisions including: vehicle dispatching, vehicle routing, charging queue management, coordinated charging, and vehicle-to-grid ancillary services.  The presentation also featured the results from the first full scale electric vehicle integration study which was recently conducted for a taxi-fleet use case in Abu Dhabi.   The study suggests a close collaboration between the Abu Dhabi Department of Transportation and the Abu Dhabi Water and Electricity Authority in future large scale deployments of electrified transportation.

The presentation draws heavily from several LIINES publications including the UAE State of Energy Report, the UAE State of the Green Economy Report, the first hybrid dynamic model for transportation electrification.  The results of this first full-scale study were first presented publicly at the 2nd IEEE International Conference on Connected Vehicles & Expo held December 2-6, 2013 in Las Vegas, NV, USA, and the Gulf Traffic Conference held December 9-10 2013 in Dubai, UAE.  These presentations demonstrated a successful collaborative project between Masdar Institute, the Abu Dhabi Department of Transportation, and Mitsubishi Heavy Industries.

In depth materials on LIINES research on transportation electrification can be found on the LIINES publication page:  http://amfarid.scripts.mit.edu

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Journal Paper Accepted at Applied Energy Journal: Quantitative engineering systems modeling and analysis of the energy-water nexus

The LIINES is happy to announce that Applied Energy Journal has accepted our recent paper entitled:  “Quantitative engineering systems modeling and analysis of the energy–water nexus” for publication.  The paper is authored by William N. Lubega and Prof. Amro M. Farid.  

Electric power is required to extract, condition, convey, dispose of and recycle water for human use. At the same time, the bulk of global electricity generation capacity uses water as a heat sink or prime mover. This energy-water nexus is of growing importance due to increased demand for water and electricity; distortion of the temporal and spatial availability of fresh water due to climate change; as well as various drivers of more energy-intense water supply for example increased wastewater treatment requirements, and more water-intense electricity generation for example emissions control technologies at power plants.

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There are several notable published studies on this nexus. At a technology level, there have been attempts to optimize coupling points between the electricity and water systems to reduce the water-intensity of technologies in the former and the energy-intensity of technologies in the latter. Empirical determinations of the electricity-intensity of water technologies and the water-intensity of electricity technologies have been reported and analyzed. Various models that enable the exploration of the water resource implications of defined electricity sector development pathways and thus support the analysis of various water and electricity policies have also been developed. To our knowledge however, a transparent physics-based approach that interfaces a model of the electricity system to models of the municipal water and wastewater systems enabling an input-output analysis of these three systems in unison has not been presented. Such a modeling approach would support integrated control applications as well as integrated planning without a priori specification of development pathways, for example through optimization.

A paper recently published by the LIINES in Applied Energy titled Quantitative engineering systems modeling and analysis of the energy–water nexus presents such a systems-of-system model. In this work, bond graphs are used to develop models that characterize the salient transmissions of matter and energy in and between the electricity, water and wastewater systems as identified in the reference architecture. Bond graphs, which are graphical representations of physical dynamic systems, were chosen as the modeling tool as they facilitate the inter-energy-domain modeling necessitated by the heterogeneous nature of the energy-water nexus. Furthermore they clearly identify causality and readily allow for model enhancement as required by applications. The developed models, when combined, make it possible to relate a region’s energy and municipal water consumption to the required water withdrawals in an input-output model.  This paper builds on another LIINES publication entitled “A Reference Architecture for the Energy-Water Nexus” found in the IEEE Systems Journal.

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This research is of particular significance to countries in the Gulf Cooperation Council, all of which have limited fresh water resources and thus depend on energy-expensive desalination to meet a large portion of their water needs. This dependence enhances the degree of coupling between the electricity and water systems and thus the associated vulnerability concerns. Furthermore, motivated by the cogeneration of electric power and desalinated water, combined electricity and water authorities have been established in the region. The multi-energy domain model developed in this work is therefore of immediate relevance to the planning and control efforts of these existing institutions.

 

About the Author:

William N. Lubega conducted this research in collaboration with his Master’s thesis advisor Prof. Amro M. Farid in LIINES at the Masdar Institute of Science & Technology Engineering Systems & Management Department.  William is now a doctoral research assistant at the University of Illinois Urbana-Champaign Civil & Environmental Engineering department as part of the Energy-Water-Environment Sustainability Track.  There, he continues his energy-water nexus research in the Stillwell Research Group.

A full reference list of energy-water nexus research at LIINES can be found on the LIINES publication page: http://amfarid.scripts.mit.edu

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Hybrid Dynamic Model for Transportation Electrification Published at the 2014 American Control Conference

Having studied the Abu Dhabi transportation systems for several years, it became clear to us that the true success of electrified transportation was its successful integration with the infrastructure systems that support them.  Left unmanaged electric vehicles may suffer from delays due to charging or cause destabilizing charging loads on the electrical grid. While many works have sought to mitigate these effects with advanced functionality such as coordinated charging, vehicle-to-grid stabilization, and charging queue management, few works have assessed these impacts as a holistic transportation-electricity nexus. To this effect, the 2014 American Control Conference (ACC) has recently published our paper on a hybrid dynamic model for transportation electrification.   Unlike traditional microscopic traffic simulators, this model considers stationary charging and online charging (while moving) as an integral part of the model rather than add-on functionality.  Thus is lends itself to usage by EV fleet operators to not just assess but also improve their operations & control.  It may also be used to coordinate the planning and operation transportation and electrical power infrastructure.

In depth materials on LIINES research on transportation electrification can be found on the LIINES publication page:  http://amfarid.scripts.mit.edu

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Journal Paper Accepted at the Energy Journal: The Impact of Storage Facility Capacity and Ramping Capabilities on the Supply Side of the Energy-Water Nexus

The LIINES is happy to announce that the Energy Journal has accepted our recent paper entitled:  The Impact of Storage Facility Capacity and Ramping Capabilities on the Supply Side of the Energy-Water Nexus.  The paper is authored by Apoorva Santhosh, Prof. Amro M. Farid and Prof. Kamal Youcef-Toumi.  It builds upon an earlier publication entitled:  Real-Time Economic Dispatch for the Supply Side of the Energy-Water Nexus which was summarized in an earlier blog post.

As previous blog posts have discussed, the topic of the energy-water nexus is timely.  In the Gulf Cooperation Council nations, it is of particular relevance because of the hot and arid climate.  Water scarcity is further aggravated high energy demands for cooling.  The GCC nations, however, have a tremendous opportunity in that they often operate their power and water infrastructure under a single operational entity.  Furthermore, the presence of cogeneration facilities such as Multi-Stage Flash desalination facilities fundamentally couple the power and water grids.

This paper expands upon the previously published economic dispatch problem to now include the impact of ramping rates and storage capacities.  The latter is shown to alleviate binding production constraints and flatten production levels to achieve lower costs.   Three cases studies are presented; a base case, a second case inspired by Singapore’s limited water storage availability, and a third case relevant to countries in the Middle East where water storage facilities can be readily constructed. Storage facilities are shown to reduce total operating costs by up to 38% and lead to less variable daily production suggesting that they have an important role to play in the optimization of the energy-water nexus.

A full reference list of energy-water nexus research at LIINES can be found on the LIINES publication page: http://amfarid.scripts.mit.edu

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Dr. Amro M. Farid contributes to Published 2015 UAE State of Energy Report

Following on the heals of the 2015 UAE State of the Green Economy Report,  we, at the LIINES, are happy to announce the release of the 2015 UAE State of Energy Report.  It is the premier benchmark publication for the nation’s energy sector.  This annual report is published by the UAE Ministry of Energy, and is created in collaboration with the United Nations Development Programme (UNDP) and Dubai Carbon. The work opens with states from his highness Sheikh Khalifa bin Zayed Al Nahyan President of the United Arab Emirates, his highness Sheikh Mohammed bin Rashid Al Maktoum, Vice President and Prime Minister of the United Arab Emirates and Ruler of Dubai, his excellency Ban Ki-Moon Secretary-General of the United Nations, his excellency Dr. Sultan Al Jaber UAE Minister of State and Chairman of Masdar, his excellency Dr. Rashid Ahmad bin Fahad Minister of Environment and Water, his excellency Saeed Mohammed al Tayer Vice Chairman of the Dubai Supreme Council of Energy, his excellency Dr. Matar Hamed Al Neyadi Undersecretary of the UAE Ministry of Energy. Also in the report, Dr. Amro M. Farid has authored  “Key Technical Challenges to Electric Vehicle Adoption in the UAE”.  It summarizes many of the conclusions from our transportation electrification research and mentioned in our previous post. The report also includes the work of LIINES alumna Reshma Francy.  She has co-authored two articles. “What are GHG Emission Estimation Methodologies?”  and “Energy Planning, Analysis and Policy Making around GHG Emissions”. For further information on how the LIINES continues to produce energy research relevant to the UAE landscape can be found on the LIINES publication page:   http://amfarid.scripts.mit.edu WhiteLogo2 LIINES Website: http://amfarid.scripts.mit.edu

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Dr. Amro M. Farid Contributes to Published 2015 UAE State of the Green Economy Report

We, at the the LIINES, are happy to announce that the 2015 UAE State of the Green Economy Report has not only been published but has also gone viral!  #stateofgreeneconomy.

The Dubai Carbon Center of Excellence coordinated the publication of the UN-backed document which describes opportunities and challenges for the green economy in the global market; focusing on the leadership of the United Arab Emirates.

The work features the commitments and support of his highness Sheikh Mohammed bin Rashid Al Maktoum, Vice President and Prime Minister of the United Arab Emirates and Ruler of Dubai, his highness Sheikh Ahmed bin Saeed Al Maktoum, Chairman of the Dubai Supreme Council of Energy, his excellency Ban Ki-Moon Secretary-General of the United Nations, His Excellency Mohammed Al Gergawi, Minister of Cabinet Affairs in the Federal Government, his excellency Dr. Rashid bin Fahad, Minister of Environment and Water, his excellency Saeed Mohammed Al Tayer, Managing Director and Chief Executive Officer of the Dubai Water & Electricity Authority, and her excellency Helen Clark Administrator of the United Nations Development Programme.

Also in the report, Dr. Amro M. Farid has authored “Electric Vehicles:  Energising the Adoption of Electrified Transportation in a Smart City”.  It summarizes many of the conclusions from our transportation electrification research.  The include five key considerations to energy the adoption of electrified transportation in the Dubai Smart City:

  1. Getting the electric transportation use case right
  2. Getting the charging infrastructure right
  3. Strengthening the existing power infrastructure
  4. Coordinating the planning of transportation and energy infrastructure
  5. Coordinating the operation of transportation and power infrastructure

In depth materis on LIINES research on transportation electrification can be found on the LIINES publication page:  http://amfarid.scripts.mit.edu

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Turkish Electric Car w/ 500km Driving Range Hits Roads

At the LIINES, we have been conducting research on Transportation Electrification for quite some time.

At heart of the research is the electric vehicle, and its challenge is that it is both a transportation artifact that exists on our everyday roads as well as an electrical artifact that must connect to the power grid.   In the first full-scale case study of its kind, we have shown in Abu Dhabi that managing this dual nature means ensuring vehicle availability through charging while not imposing overly heavy demands on the grid.

One main challenge of electric vehicles is their driving range.  Many commercially available EVs only have a range of 150km — thus requiring charging once or twice a day.   With charging times of several hours, this means that a typical driver has to think very carefully how and when this EV will be practically used.

In contrast, a recent Turkish Electric Car developed at Istanbul University has demonstrated a 500km driving range in a tour from Istanbul to Ankara.  The “T-1” as the vehicle is called weighs a mere 500 kilograms and has a top speed of 120 kilometers per hour.  And while the vehicle looks sporty sleek, it has not neglected practicality with four seats and enough room for luggage.

With the T-1, the development team builds upon earlier successes including their 8th place finish in the 2009 global electric car competition held in Australia.

 

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