Re: Selecting cars for loading + statistical observation
devansprr
--- In STMFC@..., Malcolm Laughlin <mlaughlinnyc@...> wrote:
I can't tell you some amusing tales about trying to apply linearprogramming to car distribution because that clearly required after 1961 computer capability. Malcom, Thanks for the insight from the OR perspective. Did anyone ever try to use OR to analyze historical data to see if they could spot some unknown operational problem/trend rather than solve an immediate problem? I would expect not since the people on the ground probably knew what the problems were - very different from telephones where the lack of human involvement (relative to the number of "events") led to a lack of information. Appreciate the programming humor. As an engineer that graduated about the time the PC came out, I'm continually amazed at how much analysis was accomplished during the days before computers. Lots was done in the 60's and 70's with main-frames and mini-computers, but before that - Wow! and often with very large data sets. Thanks for the help, Dave Evans
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Re: A Purpose For Frt Car Distribution Studies. Was: Re: Re:Fwd: Re: Freigh
Anthony Thompson <thompson@...>
I wrote:
"Well, most of the early Texas discoveries, around 1900, were wayIt occurs to me that most Texas think of "south Texas" as south of a line between Houston and San Antonio, so my statement will look wrong to them. Let's say Gulf Coast near and east of Houston, and short distances inland away from Houston. Tony Thompson Editor, Signature Press, Berkeley, CA 2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com (510) 540-6538; fax, (510) 540-1937; e-mail, thompson@... Publishers of books on railroad history
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A Purpose For Frt Car Distribution Studies. Was: Re: Re:Fwd: Re: Freigh
devansprr
--- In STMFC@..., "Dave Nelson" <Lake_Muskoka@...> wrote:
well more than what's on the layout (we all do that anyway), keeping the moreprolific road names in place (perhaps changing cars) and then cycling in andout lots of the smaller roads so that over a period of time, what's seen on thefleet. Dave, Good point! I have always heard over at the LDSig that you can never have enough staging, and this is a good reason to add some extra storage tracks. I've been careful to design in enough covered staging so I can store every train off-layout (during periods of dusty construction/expansion), but hadn't thought about an extra pool of boxcars to cycle the rare cars so that I can keep trains from looking a little too repetitive, or deviant ;-) (from a type and herald standpoint). Thanks, Dave Evans
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Re: A Purpose For Frt Car Distribution Studies. Was: Re: Re:Fwd: Re: Freigh
Anthony Thompson <thompson@...>
See my other post, but I thought most WWII era refineries were north of the gulf - the off-shore oil had not been developed yet.Well, most of the early Texas discoveries, around 1900, were way in south Texas. You're right that off-shore drilling wasn't much practiced there at the time (developed in California before 1900), but there were HUGE onshore Texas oil fields. You build refineries near the oil when you can. Tony Thompson Editor, Signature Press, Berkeley, CA 2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com (510) 540-6538; fax, (510) 540-1937; e-mail, thompson@... Publishers of books on railroad history
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A Purpose For Frt Car Distribution Studies. Was: Re: Re:Fwd: Re: Freigh
devansprr
--- In STMFC@..., "Bruce Smith" <smithbf@...> wrote:
As for tank cars being over-represented, that's only if you consider thenational fleet to be evenly distributed. That would be true for boxcars andmostly true for flats and reefers, but not at all true for tank cars.Bruce - sorry I mis-wrote - deviation was the wrong word - just pointing out that I will have a layout with an unusually large tank car fleet relative to other car types. I have been analyizing the '43 ORER and creating an excel file with worksheets for each car type, and then totals for each reporting mark by general characteristics for each car type (e.g. 36/40/50 foot box cars, steel vs wood sheathed, etc.) For tanks I'm characterizing by gallons - under 8k, 8k (plain and insulated), 10k (plain and insulated), and oddities (over 10k or multi-domes), gons by length, and hoppers by tons and bottom type. Still a work in progress. Haven't tackled flats, stock and reefers yet. But I do not have good info on details such as tank car manufacturer type (e.g. 11, 21, 27, etc). If that exists let me know and I'll search for it - there is a wealth of data in this site - it could use a full word index system for quicker and more accurate searches. As Ifleet of tank cars was concentrated in a series of linear routes between the gulfrefineries. Bruce, See my other post, but I thought most WWII era refineries were north of the gulf - the off-shore oil had not been developed yet. Dave Evans
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A Purpose For Frt Car Distribution Studies. Was: Re: Re:Fwd: Re: F
devansprr
--- In STMFC@..., "Mike Brock" <brockm@...> wrote:
book contain a few Sinclair tank cars. One with 59 [ 63% ] and one with 52 [22 SDRX tank cars. I have [ gasp ] 5.Mike, With all of the discussion I have lost track - your conductor book is UP main in WY post war? Modeling WWII I'm trying to keep track of which would be the likely reporting marks on tank trains that ran over the PRR in the east. Plus, I was under the impression that during this era that a lot of the refining was north of the gulf - closer to Oklahoma, northern TX, Kansas, and even eastern Colorado? Gulf coast refining flourished later after drilling started in the gulf?? Bruce, don't forget that one of the key WWII refineries was Sun oil's high-octane av-gas refinery in Marcus Hook, PA (between Wilmington DE and Philly) - I think the crude came over tunnel hill, then down through Columbia to the DC-Philly main, and then ran north through Wilmington. Sun's hi-octane fuel was thought to be a major technical breakthrough in suporting high altitude, super-charged aircraft. I think I've seen at least one picture of such a train near Wilmington in an old High Line. What I do not know is if the finished product was loaded onto ships at Marcus Hook (on the Delaware), or moved by rail up to the NYC port area. Sorry if this is getting too far off topic. Being a relative newcomer, should this type of info be on the Opsig group? Not that relevant to building freight cars. Dave Evans
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Books for sale
Mike Brock <brockm@...>
I have the following books for sale:
All books are in excellent condition. Contact me OFFLINE at brockm@... with any questions including photos of the books. Price does not include shipping. 1. The Making, Shaping, and Treatment of Steel, United States Steel, 7th Edition: $130 2. C&O Power, Staufer: $80 3. The Western Maryland Steam Album, Price: $120 4. Norfolk & Western Railway, Pocahontas Coal Carrier, Prince: $130 5. Steam & Thunder in the Timber, Michael Koch, signed: $150 Mike Brock
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Digest
Jim Sabol
Would the owner/manager of this list please assist me in receiving a
digesr of this group's e-mails rather than receiving each one in its entirety. Thanks. Jim here.
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Re: A Purpose For Frt Car Distribution Studies
Anthony Thompson <thompson@...>
Bruce Smith wrote:
A large portion of the national fleet of tank cars was concentrated in a series of linear routes between the gulf coast oil fields and the north eastern refineries . . . So for us lucky PRR modelers, we get to model a great percentage of the national fleet as it traversed Pennsy rails, but someone modeling, say the ATSF, would see very few of those cars. So in this particular case, both time and location are absolutely critical!So Bruce, what railroads do you think served those Gulf Coast refineries? Could Santa Fe be among them? But of course to model the tank trains, you'd have to model the right part of the Santa Fe at the right time--just as a Pennsy modeler has to model the right part of the PRR at the right time. As with so many things, the locality and time one is modeling CAN be entirely controlling. Seth Neumann's layout includes a car plant, so he switches lots of consists of auto racks as well as parts cars. Most of us would only be able to have such cars in bridge traffic. I once visited a layout on which was a representation of a regional GATC tank car cleaning and repair plant. Wow, could you have a big variety of tank cars in there--and not even restricted to GATX, since others could contract for work to be done there. And you can model cars in various stages of repair or re-assembly, not to mention partly painted, etc. If you love tank cars, it's hard to beat. Tony Thompson Editor, Signature Press, Berkeley, CA 2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com (510) 540-6538; fax, (510) 540-1937; e-mail, thompson@... Publishers of books on railroad history
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Re: A Purpose For Frt Car Distribution Studies. Was: Re: Re:Fwd: Re: Freigh
Mike Brock <brockm@...>
Bruce Smith writes:
"As I alluded to in an earlier message a large portion of the national fleet of tank cars was concentrated in a series of linear routes between the gulf coast oil fields and the north eastern refineries, and once the big inch pipeline was finished, between the end of the pipeline and the refineries. So for us lucky PRR modelers, we get to model a great percentage of the national fleet as it traversed Pennsy rails, but someone modeling, say the ATSF, would see very few of those cars. So in this particular case, both time and location are absolutely critical!" Hmmm. I'm not so sure of that. Checking, I note that the train of tank cars [ MT's ] I referred to was on the Frisco, at Sullivan between St. Louis and Spingfield running to Oklahoma during WW2. Santa Fe might actually also been the recipient of such traffic going from Texas and Oklahoma into Kansas City. Incidentally, I note that two of the 35 trains in my frt conductor's book contain a few Sinclair tank cars. One with 59 [ 63% ] and one with 52 [ 42% ]. Based on max train lengths of 35 cars, that means I will need 22 SDRX tank cars. I have [ gasp ] 5. Something tells me... Mike Brock
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division of revenue
Malcolm Laughlin <mlaughlinnyc@...>
Tim O'Connor wrote
" All participating lines in a given routing would have to have some prior agreement regarding the division of revenues for THAT particular tariff, and there were tens of thousands of tariffs." --------------------- This was not the case (before the 80's). Divisions were almost completely independent of tariffs. They were governed by division sheets that applied to all traffic. The divisions were private agreements among railroads that were not public documents as tariffs were. There were national division sheets and many sheets for two or more railroads for particular routes. This information leaked into the public domain only when the railroads could not agree and one or more protested to the ICC that the divisions were unfair. Freight agents and shippers knew very little about divisions. Thye were appled in the railroad revenue accounting offices after the freight had been delivered an billed. With the millions of individual tariff items, there was no possibility of having a division sheet for each tariff in the days BC. Malcolm Laughlin, Editor 617-489-4383 New England Rail Shipper Directories 19 Holden Road, Belmont, MA 02478
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Selecting cars for loading + statistical observation
Malcolm Laughlin <mlaughlinnyc@...>
My apologies for taking so long to replay to all of these interesting posts. On top of an extemely busy week, the hard disk on my office computer crashed and I'm just now catching up.
I’d like to address Dave Evans’ comments about how cars were loaded. 1) and the other for Harrisburg, and he has a bunch of empty 40 foot XM's - including one PRR, and one NYC, would he just flip a coin? Or do the agents not know the load's destination, only that a shipper needs a 40' XM?----------- In theory the agent should ascertain from the shipper where the loads were going and select cars accordingly. Among the reasons that the desired result was not achieved. It would have been necessary to reswitch the empty box car track to get the right cars to the right shipper. Not likely to happen. The first ten cars go to shipper A, the next five to B, etc. No agent was going to refuse bills of lading because the shipper put the Elkhart load in the PRR car and the Altoona laod in the NYC car. Looking at it from the point of view of the shipper’s loading dock. Say there are ten cars going to ten consignees with similar loads. The loading dock foreman has ten loading orders. He puts the first order in the first car and the tenth order ends up in the 10th car. So the car that gets each laod depends on the sequence in which the orders were typed in the sales office. Nothing to do with marks of cars. 2), is it more likely that the NYC yard clerks would have it routed over the NYC's water-level route, rather than to the PRR, which could get it there over a slightly shorter distanceYard clerks did not route cars. The freight agent receiving the shipper’s bill of lading copied the routing on the bill. If the shipper specified railroads but not junctions, the agent chose the junction giving his road the long haul, provided it was a service route. If the shipment was completely unrouted by the shipper, he would give his road the long haul and select the rest of the route based on service and friendly connections. > 3) There is still the issue of statistical variations……….A little research found that Bell Labs/AT&T spent a ton of money developing the operations research for modeling these sorts of problems (it directly impacts the size of telephone systems). Turns out the deviations from average are often significant for many processes, especially if they involve processes that are not purely random I took a couple of OR courses when I was at MIT. What I found in the real world of railroads was 1) The distributions were so lumpy that statistical methods usually didn’t work. 2) You couldn’t get any meaningful data from the field to plug in to the models. 3) What data you could get would be far enough behind that the results were out of date before transmission to the filed. For example, I was asked to work on a model for diverting MDT reefers from the NYC main line to Weehawken for banana loading. But the railroad had a daily cycle imposed on a weekly cycle. Maybe there was a boat arriving every eight days. But the standard deviation of time between arrivals was two days and might be affected by labor in Central America and weather at sea. Now try to develop an algorithm for diverting the cars to Weehawken. Oh, and other variability – the flow of cars past the diversion point (Selkirk, congestion state of the yard and variations in train operations. I actually did get some useful results with graphical inventory control models, but nothing more sophisticated was worth doing. I can’t tell you some amusing tales about trying to apply linear programming to car distribution because that clearly required after 1961 computer capability. Malcolm Laughlin, Editor 617-489-4383 New England Rail Shipper Directories 19 Holden Road, Belmont, MA 02478 [Non-text portions of this message have been removed]
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Selecting cars for loading + statistical observation
Malcolm Laughlin <mlaughlinnyc@...>
My apologies for taking so long to replay to all of these interesting posts. On top of an extemely busy week, the hard disk on my office computer crashed and I'm just now catching up.
I’d like to address Dave Evans’ comments about how cars were loaded. 1) and the other for Harrisburg, and he has a bunch of empty 40 foot XM's - including one PRR, and one NYC, would he just flip a coin? Or do the agents not know the load's destination, only that a shipper needs a 40' XM?----------- In theory the agent should ascertain from the shipper where the loads were going and select cars accordingly. Among the reasons that the desired result was not achieved. It would have been necessary to reswitch the empty box car track to get the right cars to the right shipper. Not likely to happen. The first ten cars go to shipper A, the next five to B, etc. No agent was going to refuse bills of lading because the shipper put the Elkhart load in the PRR car and the Altoona laod in the NYC car. Looking at it from the point of view of the shipper’s loading dock. Say there are ten cars going to ten consignees with similar loads. The loading dock foreman has ten loading orders. He puts the first order in the first car and the tenth order ends up in the 10th car. So the car that gets each laod depends on the sequence in which the orders were typed in the sales office. Nothing to do with marks of cars. 2), is it more likely that the NYC yard clerks would have it routed over the NYC's water-level route, rather than to the PRR, which could get it there over a slightly shorter distanceYard clerks did not route cars. The freight agent receiving the shipper’s bill of lading copied the routing on the bill. If the shipper specified railroads but not junctions, the agent chose the junction giving his road the long haul, provided it was a service route. If the shipment was completely unrouted by the shipper, he would give his road the long haul and select the rest of the route based on service and friendly connections. > 3) There is still the issue of statistical variations……….A little research found that Bell Labs/AT&T spent a ton of money developing the operations research for modeling these sorts of problems (it directly impacts the size of telephone systems). Turns out the deviations from average are often significant for many processes, especially if they involve processes that are not purely random I took a couple of OR courses when I was at MIT. What I found in the real world of railroads was 1) The distributions were so lumpy that statistical methods usually didn’t work. 2) You couldn’t get any meaningful data from the field to plug in to the models. 3) What data you could get would be far enough behind that the results were out of date before transmission to the filed. For example, I was asked to work on a model for diverting MDT reefers from the NYC main line to Weehawken for banana loading. But the railroad had a daily cycle imposed on a weekly cycle. Maybe there was a boat arriving every eight days. But the standard deviation of time between arrivals was two days and might be affected by labor in Central America and weather at sea. Now try to develop an algorithm for diverting the cars to Weehawken. Oh, and other variability – the flow of cars past the diversion point (Selkirk, congestion state of the yard and variations in train operations. Malcolm Laughlin, Editor 617-489-4383 New England Rail Shipper Directories 19 Holden Road, Belmont, MA 02478 [Non-text portions of this message have been removed]
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Re: Tim Gilbert's work - LCL
water.kresse@...
There are still a one or two folks at CF that started out working as "on call" laborers at the LCL operation in CF. Good place to get your foot in the door and get to know someone who could get you a better job . . . if you worked hard. The retirees use to meet at the "Come to Corn Bread and Beans" lunches at the freight house to get together . . . before it became the Heritage Center. Don't know, with the layout, if there is room there anymore.
toggle quoted messageShow quoted text
Al Kresse
-------------- Original message --------------
From: Malcolm Laughlin <mlaughlinnyc@...> " I planned to share some of Tim's LCL research (a whole other kettle of fish) in some way in that magazine. " ---------- Although I strongly disagree with Tim's conclusions on car fleet distribution (more later today), I will piggyback on the above statement, with which I agree. When Tim visited our club he brought a wealth of data on C&O LCL operations. Our LCL operation is centered on Elkton, VA, not far from the actual C&O terminal at Clifton Forge. Thanks to Tim and the use of selective compression, we have a set of LCL routes that relfects the traffic flow proportions implied by the C&O data. Malcolm Laughlin, Editor 617-489-4383 New England Rail Shipper Directories 19 Holden Road, Belmont, MA 02478
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Re: A Purpose For Frt Car Distribution Studies.
Dang, there goes my searchlight car...
toggle quoted messageShow quoted text
Prototype N Scale Models (TM) by George Hollwedel 310 Loma Verde St Buda, TX 78610-9785 512-796-6883 www.micro-trains.com/sr-0806-hollwedelATSF.php www.micro-trains.com/hollwedel.php www.imrcmodels.com/n/sr/html/GHollATSFExpressN.htm
--- On Fri, 8/15/08, al_brown03 <abrown@...> wrote:
From: al_brown03 <abrown@...>
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Tim Gilbert's work - LCL
Malcolm Laughlin <mlaughlinnyc@...>
" I planned to share some of Tim's LCL research (a whole other kettle of fish) in some way in that magazine. "
---------- Although I strongly disagree with Tim's conclusions on car fleet distribution (more later today), I will piggyback on the above statement, with which I agree. When Tim visited our club he brought a wealth of data on C&O LCL operations. Our LCL operation is centered on Elkton, VA, not far from the actual C&O terminal at Clifton Forge. Thanks to Tim and the use of selective compression, we have a set of LCL routes that relfects the traffic flow proportions implied by the C&O data. Malcolm Laughlin, Editor 617-489-4383 New England Rail Shipper Directories 19 Holden Road, Belmont, MA 02478
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Re: A Purpose For Frt Car Distribution Studies.
Anthony Thompson <thompson@...>
Al Brown wrote:
What?!? You mean that Coast Guard guided-missile car shouldn't have arch-bar trucks??!? Say it ain't so!Well, at least the missile, its markings, and the launcher are accurate <g>. Tony Thompson Editor, Signature Press, Berkeley, CA 2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com (510) 540-6538; fax, (510) 540-1937; e-mail, thompson@... Publishers of books on railroad history
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Re: tax vs. customs
Anthony Thompson <thompson@...>
Malcolm Laughlin wrote:
And speaking of "tax authorities" that may be too much of a generalization. Is it federal income tax, state sales tax or other. Think of how many of us casually viloate state sales tax rules by not reporting purchases in other states.Good question. Earlier posters, who seemed to have SOME knowledge, just said "tax consequences." Someone still on the list may know more. But how an individual handles tax issues is not usually how a corporation behaves. Tony Thompson Editor, Signature Press, Berkeley, CA 2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com (510) 540-6538; fax, (510) 540-1937; e-mail, thompson@... Publishers of books on railroad history
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Re: A Purpose For Frt Car Distribution Studies.
al_brown03
--- In STMFC@..., Tim O'Connor <timboconnor@...> wrote:
What?!? You mean that Coast Guard guided-missile car shouldn't have arch-bar trucks??!? Say it ain't so! Al Brown, Melbourne, Fla.
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Re: Question re Tichy USRA hopper - HO
Jonathan Grant <jonagrant@...>
Thanks for the invaluable help with the information. I'll post a photo
of the hopper when I'm done, probably tomorrow. Jon
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