[Themaintainers] Maintenance engineering coursework?

Thu Apr 8 20:48:40 EDT 2021

Thanks Melinda.

I understand the nuance. Thank you. That clarifies my objection. I see the
place for Weibull.
I hope this is making for interesting conversation for others in the group
else happy to connect separately. (for the mods :)

I'm affiliated with efforts to apply machine learning techniques to risk
ranking bare steel pipe replacements and leak survey programs using asset
and leak data that is enriched with external data such as weather and soil.

One of the datasets we rely on is US soil data, that contains specific
attributes on "Steel Corrosion" ~ the susceptibility of uncoated steel to
corrosion when in contact with the soil.
As you may be able to see here <https://imgur.com/a/oyGlEXO> there's
quite a lot of variation suggesting that a pipeline can have different
shapes of deterioration curves as it comes in contact with different types
of soil.

Add in precipitation events, and you have specific sections of pipe
subjected to varying intensities of corrosion.
Pipeline engineers do implement cathodic protection to stave off corrosion
in some of these areas.

Furthermore, we also found an interesting (though somewhat weak)
relationship between corossion based leak events and lunar cycles.
We found that Underground infrastructure in areas with large underground
aquifers are subject to groundwater tides or earth tides
<https://theconversation.com/squeezed-by-gravity-how-tides-affect-the-groundwater-under-our-feet-74928#:~:text=Effect%20of%20tides%20on%20groundwater&text=The%20gravity%20change%20from%20Earth,results%20in%20a%20downward%20squeezing.>
where
the same forces that affect ocean tides exerts *a pull *on moisture from
the groundwater thereby subjecting these pipes to more exposure to moisture
and therefore more corrosion.

I often come across Weibull models in the industry and I feel that I am
somewhat biased that modeling degradation using external factors like soil
and weather is *better than relying solely on a statistical analysis of end
of life events.*

In other words Maintenance based on only looking at reports of outcome  vs
Maintenance based on signals revealed from revealing hidden / complex
forces that assets are subject to...
....feels like the story of Abraham Wald and his famous Survivorship Bias
experiment  <https://en.wikipedia.org/wiki/Survivorship_bias>

Feel like many epistemic swords are pointed in my direction for saying
that!

Always Happy to be proven wrong!!!

On Thu, Apr 8, 2021 at 7:12 PM Melinda Hodkiewicz <
melinda.hodkiewicz at uwa.edu.au> wrote:

> Hi Varun
>
> A key part that is missing here is that you cannot predict with certainty
> a rate of failure or a mean life from a Weibull distribution. Consider a
> probability density function of men’s height. Assume it is normally
> distributed. You cannot predict your height from this distribution. Your
> height is one of many data points. You can only say that the mean height is
>  5 ft 10 ft with a Stdev of say 3 inches. The same with a Weibull
> distribution. The data comes from a sample of end of life events, you can
> only estimate the mean life from this. Any use of this in prediction is
> fraught with uncertainty, especially if the std dev is high.
>
>
>
> However, you can use reliability techniques incorporating Weibull
> distribution for the life of pipelines together with other covariates to
> risk rank assets for prioritisation of maintenance taking into account left
> censoring you mention below. Note I am not claiming to predict the life
> here, but the identify which pipes are more likely to block (failure)
> relative to other pipes in the set. There is a nice short video using a
> large waste water pipe data set explaining this from a recent conference if
> you are interested. I’m happy to share a couple more papers as well if this
> is of interest.  https://www.youtube.com/watch?v=zZRy5MUsUJc
>
>
>
> If you want to predict the life for a specific pipe then the engineers
> should be using a Bayesian approach, with a prior based on the population
> data (maybe based on a Weibull distribution) and covariates (based on
> condition assessment) specific to the asset. There are an increasing number
> of papers demonstrating this. Done well, this can deal with the left
> censoring and will provide parameters for the distribution with their own
> uncertainties. However few reliability engineers have any Bayesian stats
> training as college course are frequentist based.
>
>
>
> Happy to chat more, Melinda
>
>
>
>
>
>
>
>
>
>
>
> *From:* Varun Adibhatla (ARGO) <varun at argolabs.org>
> *Sent:* Friday, 9 April 2021 6:02 AM
> *To:* Melinda Hodkiewicz <melinda.hodkiewicz at uwa.edu.au>
> *Cc:* Varun Adibhatla (ARGO) <varun at argolabs.org>; krones at bc.edu;
> themaintainers at lists.stevens.edu
> *Subject:* Re: [Themaintainers] Maintenance engineering coursework?
>
>
>
> Melinda,
>
>
>
> I'm so glad you unpacked Weibull here. I've had a bit of
> a long-standing issue with its use in the Gas industry.
>
>
>
> As I understand it, Weibull models originated in modeling Aircraft & Rail
> hazards.
>
>
>
> A somewhat precise rate of failure can be calculated from the knowledge 3
> key parameters which is known for Air and Rail Assets
>
>    - A precise time of creation is known (airframes, rail manufacture
>    date)
>    - A precise time of failure is known because the consequence of
>    failure is very high (air crashes and rail derailments)
>    - Frequent condition assessments of the underlying asset offer some
>    level of degradation over time.
>
> For GAS assets however,
>
>    - create_time is largely unknown especially for those assets that were
>    installed pre-computer.
>    - The exact time of failure is unknown since a leak can start out as a
>    really small (pinhole) and graduate into larger leaks over time and this
>    rate is a factor of a lot of external conditions (soil movement etc.)
>    - Frequent condition assessments are almost impossible because these
>    assets are well buried underground.
>
> So my argument has been that because of these missing data points, Weibull
> should not be applied to model Gas Asset Reliability.
>
> Am I missing something?
>
>
>
> Varun
>
>
>
> On Tue, Apr 6, 2021 at 6:30 PM Melinda Hodkiewicz <
> melinda.hodkiewicz at uwa.edu.au> wrote:
>
> Hi Varun
>
> Many thanks for all your information which I enjoyed.
>
>
>
> I thought I might just share some more information on Weibull.  “Weibull
> analysis” is thought of as a process because there are now a bunch of
> software packages that support engineers to do this, but all it is the
> fitting of life data to a Weibull distribution. The Weibull is in a family
> of distributions such as the Normal Distribution (taught at school),
> LogNormal, Possion etc. The Weibull fit is also widely used in medicine.
> Anyway, it is used to plot time to event data, include both failures and
> suspensions, and the parameters of the fit are used to determine a “shape”
> parameter and a “location” parameter. The value of the shape parameter
> gives an indication of “early life failures”, “random” failures and “wear
> out failures”, and the location parameter can be used to estimate the mean
> time between failure.
>
>
>
> However it does rely on data! So if you have very few failures it is not a
> good approach, also if the failures are not random variables that are IID,
> independent and identically distributed then you should not use a Weibull
> plot approach. This is one of the reason why it’s use in gas pipelines
> needs to be done carefully as often the events are not IID.
>
>
>
> Anyway, many many people use Weibull software packages by plugging in
> times to events and pressing play. But in reality this approach has some
> statistical pre-conditions, and does not play nicely when, for example, you
> have data sets where a large proportion of assets are pre-emptively
> replaced (we call these suspensions) as happens in the airlines.
>
>
>
> Any statistician can teach the mechanics of fitting data to a Weibull plot
> but few have been taught the significance of the use of the shape and
> location parameters to reliability engineers!
>
>
>
> Happy to share more on this, Melinda
>
>
>
>
>
>
>
> *From:* themaintainers-bounces at lists.stevens.edu <
> themaintainers-bounces at lists.stevens.edu> *On Behalf Of *Varun Adibhatla
> (ARGO)
> *Sent:* Tuesday, 6 April 2021 10:29 AM
> *To:* krones at bc.edu
> *Cc:* themaintainers at lists.stevens.edu
> *Subject:* Re: [Themaintainers] Maintenance engineering coursework?
>
>
>
> Hi Jonathan,
>
>
>
> So excited for you and this curriculum! I hope some of the below is
> helpful to you and your students.
>
>
>
> You may be familiar with John Sterman's @ MIT Capability Traps and his
> work re-engineering MIT's campus infrastructure to avoid such traps. It's
> summarized in a nice video here
> <https://aus01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DBv6vyf8AFD8&data=04%7C01%7Cmelinda.hodkiewicz%40uwa.edu.au%7Cd846b800f8864bee7fd308d8fada21a1%7C05894af0cb2846d8871674cdb46e2226%7C1%7C0%7C637535162088197786%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=1fnLeaI9%2FwuKFJO58lCYLpemsk3Ya3g2%2FCQYR0Lp9Ig%3D&reserved=0>
>
>
>
> Resonating what David Albrecht mentioned earlier, "American Cities are
> run like Ponzi schemes"
> <https://aus01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D7IsMeKl-Sv0&data=04%7C01%7Cmelinda.hodkiewicz%40uwa.edu.au%7Cd846b800f8864bee7fd308d8fada21a1%7C05894af0cb2846d8871674cdb46e2226%7C1%7C0%7C637535162088207785%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=Fi4LtlGa48BnPqqj6%2FUucrzljNVLNc8gUQnLxrjO6nw%3D&reserved=0> is
> a great explainer of how maintenance is often deferred in lieu of  growth
> narratives.
>
>
>
> My own work over the past 6 years has centered around interrogating our
> commons (physical and digital) through a lens of leaks, cracks, and holes
> and designing systems that prioritize proactive maintenance.
>
> I've worked with local governments through Project SQUID
> <https://aus01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.hackster.io%2Fargo%2Fsquid-street-quality-identification-a43367&data=04%7C01%7Cmelinda.hodkiewicz%40uwa.edu.au%7Cd846b800f8864bee7fd308d8fada21a1%7C05894af0cb2846d8871674cdb46e2226%7C1%7C0%7C637535162088217773%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=hbhdLDwClAPwpAGYqPDT9AY6zpS3Ok2V%2BHBT%2FZZ%2BBAY%3D&reserved=0>
> an attempt to show how low-cost and frequent digital surveys of street
> distress (potholes) could change the paradigm to proactive maintenance.
>
> Here's the former commissioner of NYC DOT, Lou Riccio explaining Pothole
> Analytics
> <https://aus01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3Du4ohbduvVrM&data=04%7C01%7Cmelinda.hodkiewicz%40uwa.edu.au%7Cd846b800f8864bee7fd308d8fada21a1%7C05894af0cb2846d8871674cdb46e2226%7C1%7C0%7C637535162088217773%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=aBmLVgg1uavc8PFaxTxY9V0sJTryQC1N0Y0dl1A8NIY%3D&reserved=0>
>
>
>
> For the past 2 years, I've worked with US Gas Utilities on the maintenance
> of Underground Gas Infrastructure.
>
> I've encountered a broad range of maintenance positions - ranging from
> those who take immense pride in performing regular leak surveys to those
> who operate on a "what we don't know won't hurt" viewpoint of criminal
> ignorance.
>
> Some other interesting facts from the Gas Industry. Some of NYC's Gas
> Pipes built in the late 1800s are in better condition than those in the
> 1960s. As an anonymous commenter on this NYT article states, "the bean
> counters" of yore are partly responsible for the sorry state of our
> infrastructure." and he's right (to an extent)
>
> The McNamara effect of bringing management science into civilian
> infrastructure operations did result in relatively more brittle
> infrastructure.
>
> Interestingly, I've also encountered how Weibull analysis (from
> Reliability Engineering?) a method of forecasting failure in aviation
> systems has found itself in forecasting breaks in Gas Pipelines.
>
> Your local Gas utility (Boston Gas) may have some amazing first hand
> knowledge.
>
> Last point re: Underground Infrastructure is how maintaining a National
> Underground Asset Register saves Japan upto $10 Billion / year in avoiding
> underground damages.
>
>
>
> The Civilian Conservation Corps
> <https://aus01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fvimeo.com%2F150192017&data=04%7C01%7Cmelinda.hodkiewicz%40uwa.edu.au%7Cd846b800f8864bee7fd308d8fada21a1%7C05894af0cb2846d8871674cdb46e2226%7C1%7C0%7C637535162088227773%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=9%2FG043wkIsqI7j7KlO%2F0UHkxNbMss8m14Lb9x%2FrORFo%3D&reserved=0>
> was touted as FDR's Tree Army but really started out educating the public
> about proper soil maintenance
>
> Nadia Eghbal's explanation of Open Source Stewards and the work it takes
> to maintain critical open source infrastructure is wonderful
> <https://aus01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fyoutu.be%2F5wLKnN3To-k&data=04%7C01%7Cmelinda.hodkiewicz%40uwa.edu.au%7Cd846b800f8864bee7fd308d8fada21a1%7C05894af0cb2846d8871674cdb46e2226%7C1%7C0%7C637535162088227773%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=ekwkEArPF%2FdrPZanXRsFq2Xu4R4EIxnpJSrm2Phu8nk%3D&reserved=0>
>
> The Pruitt-Igoe Myth
> <https://aus01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D8CAfACI7LBY&data=04%7C01%7Cmelinda.hodkiewicz%40uwa.edu.au%7Cd846b800f8864bee7fd308d8fada21a1%7C05894af0cb2846d8871674cdb46e2226%7C1%7C0%7C637535162088237765%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=fNZ21vg1Crsfj0%2FUMek6m6bciotUVN4yHBKE9wXESW4%3D&reserved=0>
> is a wonderfully made and heart wrenching documentary that tells the story
> of how one of the largest public housing projects in the country was set up
> to fail in part because no funds were allocated for operations and
> maintenance.
>
>
>
> Lastly, in the "wake" of the recent blockade of the Suez, my father sailed
> the high seas for 30+ years, mostly within the noisy engine rooms
> maintaining 50-100,000 horsepower engines in the middle of nowhere.
>
> His maintenance stories are magnificent and over the pandemic, we
> recounted one of his more illustrious tales
> <https://aus01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fvr00n.medium.com%2Fa-breach-in-the-forecastle-d9c0d3ec0da8&data=04%7C01%7Cmelinda.hodkiewicz%40uwa.edu.au%7Cd846b800f8864bee7fd308d8fada21a1%7C05894af0cb2846d8871674cdb46e2226%7C1%7C0%7C637535162088237765%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=CkMmMmDDHSy8EOfVMlAVGvOuhRCuT9TARqSo7H1NtZI%3D&reserved=0> on
> the high seas.
>
>
>
> PS: I presented a Guild of Leaks, Cracks, and Holes
> <https://aus01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdocs.google.com%2Fpresentation%2Fd%2F14pU0qJ4CCwsRyT6t0aKOrO7WxJ8pPV10UAXDAYZMLRM%2Fedit%23slide%3Did.g620b1c1846_0_0&data=04%7C01%7Cmelinda.hodkiewicz%40uwa.edu.au%7Cd846b800f8864bee7fd308d8fada21a1%7C05894af0cb2846d8871674cdb46e2226%7C1%7C0%7C637535162088247758%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=SeA3mr%2FZbQOQyAbYVkbwoYgP0JZq%2BF8aQ7ee2oG%2B6Z4%3D&reserved=0>
> at the last Maintainers conference where I cheekily appropriated JFK's 1962
> Moon speech to focus on "the other hard things" than the fabled moonshot.
> It also has some references to solid articles in the Economist that
> highlight the importance of Maintenance.
>
>
>
> On Mon, Apr 5, 2021 at 8:40 PM Rollie Cole <rolliecole at gmail.com> wrote:
>
> I have several relatives who were accountants, one even a professor of
> accounting. I am all in favor of getting everybody to understand some
> accounting concepts.
>
>
>
> But the example below I find problematical. A $1M road with a 20-year life
> SHOULD not require zero maintenance for 20 years, then a sudden $1M (plus
> whatever inflation has done) to replace. Instead, IF it is maintained, it
> should last not 20 years, but decades beyond that. In the process, the road
> "owner" might well spend roughly $1M each 20 years, but it should be spread
> over maintenance all during each 20-year period.
>
>
>
> I do agree, however, that many, many (far too many!) cities defer
> maintenance year after year until replacement is the only option.
> Accounting is a way to track how bad a practice that is, but does not
> itself cure the bad practice. It is perhaps necessary, but never sufficient.
>
>
>
> On Mon, Apr 5, 2021 at 5:59 AM David Albrecht <albrecht.dr at gmail.com>
> wrote:
>
> Rental property operator and software engineer here.
>
>
>
> I don't think a course like this is complete without some discussion of
> accounting. At the risk of stating the obvious, accounting is the
> accumulated body of knowledge on how to quantify economic activity.
> Probably half if not more maintenance problems are ultimately rooted in
> poor accounting, specifically focusing too much on cashflow and not enough
> on the balance sheet.
>
>
>
> Simple but obvious example to illustrate the point. A municipality spends
> $1 million on a new road with an estimated lifetime of 20 years. Next year,
> they collect $500k in tax revenue and spend $475k. Yay, a surplus! Cut
> taxes! Except the simple math of $1 million/20 years for our road shows you
> need to be tracking the $50k annual wear and tear...somewhere. Most
> organizations -- many municipalities and unsophisticated rental property
> operators -- don't do this well, and are caught short when a major capital
> item hits end-of-life, causing them to scramble to get a loan and fall
> farther and farther into debt they have no way to service.
>
>
>
> I think the solution is to emphasize a culture of continuous, incremental
> capital replacement in an organization. I haven't seen too many
> organizations (especially in the public sector) with the discipline to
> accumulate huge piles of cash for lumpy capital spending, without
> shenanigans taking place that cause the money to get redirected for other
> short-term uses. I'd love to know if I'm wrong about this.
>
>
>
> On Sat, Apr 3, 2021 at 5:02 PM Melinda Hodkiewicz <
> melinda.hodkiewicz at uwa.edu.au> wrote:
>
> Hi Jonathan,
>
> I am a maintenance engineer and for many years have taught university and
> executive education courses on maintenance, asset management, reliability,
> risk and safety. I was Australia’s representative on the development of the
> ISO55000/1/2 set of Asset Management Standards. Maintenance is one of the
> major elements of asset management. A good reference to all things AM is
> the GFMAM sute (Global Forum on Maintenance and Asset Management)
> https://gfmam.org/global-collaboration
> <https://aus01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgfmam.org%2Fglobal-collaboration&data=04%7C01%7Cmelinda.hodkiewicz%40uwa.edu.au%7Cd846b800f8864bee7fd308d8fada21a1%7C05894af0cb2846d8871674cdb46e2226%7C1%7C0%7C637535162088257751%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=CVaHD5HClqJufCBgfaNr%2FgxpAXjju%2BeDHz3BVpOjh5I%3D&reserved=0>.
> Their publications page is a useful source of teaching materials.
> Can I suggest, all found (for free) on this page.
>
> ·       The AM Landscape,
>
> ·       The Maintenance Framework, and
>
> ·       The Value of Asset Management.
>
> The Maintenance Framework book will be particularly helpful for
> engineers-in-training as it covers the maintenance management process
> (identify work (maintenance strategy)-schedule-planning-execution) that
> they are most likely to be exposed to when they graduate if they work for
> an asset operating organisation.
>
>
>
> About 7 years ago I was asked to develop a one semester class for final
> year engineers of all disciplines (process, mech, civil, elec, software,
> chemical, mining) on risk, reliability and safety. Maintenance is covered
> in detail as it is one of the main ways we manage risk. Attached is an
> overview of the unit if you are interested. Below is a brief overview:
>
>
>
> “*The unit aims to provide a holistic an integrated overview of the
> theory and practice in the fields of risk, reliability and safety, to
> prepare our engineers for professional practice. The unit develops
> students' technical and statistical skills and covers the social and
> organisational contexts, extending the students’ field of view beyond the
> technical to consider the customer and the organisation’s needs. The unit
> is taught to all engineering disciplines in one class to reinforce the need
> for cross-discipline collaboration and accommodation of different
> stakeholders and perspectives in risk and safety management*.”
>
>
>
> The class is huge >300 students and taught twice a year. It is co-taught
> with a statistician and my part (the engineering part) in taught using
> flipped learning and case study based interactive workshops.
>
>
>
> Very happy to share what we have learned over the last 7 years, ideas and
> materials. We have taught this unit to over 4000 students.
>
> Regards Melinda
>
>
>
>
>
> Professor Melinda Hodkiewicz
>
> BA Hons (Oxon), PhD, CEng, FTSE
>
> BHP Fellow for Engineering for Remote Operations
>
> Faculty of Engineering and Mathematical Sciences
>
> University of Western Australia
>
> M050, UWA, Crawley, Perth, WA 6009
>
> Melinda.hodkiewicz at uwa.edu.au
>
>
>
>
>
>
>
>
>
>
>
> *From:* themaintainers-bounces at lists.stevens.edu <
> themaintainers-bounces at lists.stevens.edu> *On Behalf Of *Jonathan Krones
> *Sent:* Saturday, 3 April 2021 3:39 AM
> *To:* themaintainers at lists.stevens.edu
> *Subject:* [Themaintainers] Maintenance engineering coursework?
>
>
>
> Hi Maintainers,
>
>
>
> First time caller, long time lurker. I'm starting work on a new syllabus
> for an upper-level undergraduate general engineering elective tentatively
> called "Maintenance Engineering" (although I'll probably need to snazz it
> up to get any enrollment). The idea is to cover concepts from a variety of
> engineering fields (e.g., civil, software systems, materials,
> manufacturing, product design) that relate to issues of maintenance,
> repair, and other types of life extension of engineered systems. I'm still
> in early stages and am interested in learning about any similar courses
> that folks in this community might know. I'm also open to suggestions on
> topics or concepts that you think should go into a course like this. It
> will likely be a combination of probability/statistical models, systems
> engineering concepts, and the engineering science bases of inspection,
> preventative maintenance, repair and remanufacturing, etc.
>
>
>
> Thanks,
>
> Jonathan
>
>
>
> --
>
> *Jonathan S Krones, PhD*
>
> Core Fellow / Visiting Assistant Professor | Boston College
>
> Research Affiliate | MIT Olivetti Research Group
>
> jonathan.krones at bc.edu | 301.788.4206
>
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> Thank You,
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> Varun Adibhatla
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> ARGO
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> Thank You,
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> Varun Adibhatla
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> ARGO
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> 347-815-3383
>

-- 
Thank You,
Varun Adibhatla
ARGO
347-815-3383
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