It will take me some time to analyze your question, although it still continue to move the activities there is a possibility of other issues not being considered, I am also finding issues on the calculated total float for the driver of CCC, this is another issue. If latter you can e-mail me a P3 file then it will be easier for me to model what you are observing.
I was also thinking in the possibility of using consumable resources. Using negative consumption the predecessors can replenish the resource from 0, the successor activity will not be able to start until you have the required resources, but I do not have this functionality as to explore it. I was also thinking about the activity consuming the resource but at the same time replenishing it at the same rate as to prevent the resource from being consumed and still being able to be replenished by other activities and used for constraining the start of other activites.
Do you have another idea?
Best regards,
Rafael
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Submitted by Vladimir Liberzon on Sun, 2009-10-04 15:14
what if your activities are in the middle of some schedule?
Then ALAP will not work.
Besides, SF means that AAA and BBB will finish after CCC starts. It means that CCC can start early - it may happen as the result of resource levelling.
Please clarify.
Best Regards,
Vladimir
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Submitted by Rafael Davila on Sun, 2009-10-04 14:37
Ironically activity CCC is set to be the predecessor, the links are the following
CCC --> SF0 --> AAA
CCC --> SF0 --> BBB
CCC has a “As late as possible” Float Constraint
I uploaded the P3 file under the following link so anyone can download it and explore it, because I am using SureTrak you will have to adjust your Layout.
I mentioned this task just as an example of questions that are asked in our forum. I am glad that Suretrak can do it though I did not understand about SF relationship with ALAP constraint.
Hi Carlos,
Spider Project has "jump to predecessor/succesor" function and can export/import to MS Project and P6. It has no direct export to P3 but exports to mpx that P3 understands.
Besides it exports/imports to text and databases. Any Spider table can be exported to Excel and vice versa.
Spider shows links of current activity in the diagram. Clicking on the preceding or succeding activity you will see its properties including links, Then you can click on another preceding or succeding activity and again see its properties (duration, volume, assignments, links, etc.).
Best Regards,
Vladimir
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Submitted by Carlos Arana on Sun, 2009-10-04 13:35
Hi. Has Spider project that useful for everything "jump to predecessor/succesor" button P3 has? In 2 clics, it takes you to the predecessors of an activity. It is very useful, I dont know why it is not a feature of modern software, they seem to be focusing in making things more and more complicated instead of making common tasks more easygoing.
This is what I mean, I can get the driving sequence of an activity just by following its driving predecessors:
Sequential application of Optimization Plus and then Advanced using Super Float as Priority will yield better results, and this is without using activity priority. Don't ask me, trial and error, brute force, took me less than 2 minutes though.
What stands out is that even a schedule known to be difficult to optimize is not that far from optimum with Spider Project Optimization Plus out of the box. I would dare to say on real life jobs Spider will be between 6% and 0% of optimal with an average of 3%, with a distribution close to 3%.
No way you can consistently get there using preferential links as to mimic true resource leveling.
Believe me I have seen software that can go as far as 40% over Spider, say 43% over optimal, and this is unacceptable.
In schedules where partial assignments are allowed Spider stands out as it can even allocate for variable partial assignment. Partial assignments is the order of the day in construction schedules as well as in architectural design schedules where you have some crews or individual resources assigned to work on several long duration activities the same day.
Variable assignment is a refinement over fixed partial assignment that will make a huge difference when allowed.
Spider Demo is limited to 40 activities but if you want to explore the 10x10 schedule maybe using the Free Spider viewer you can explore the files. You can download the file from the following link.
"You can consider the set of activities that precede current activity as the separate project with its own critical path, DRAG values, etc."
Seems like the equivalent of Longest Path, this is useful and relevant functionality.
"I want to simulate that next activity can start if any one of two preceding activities is finished. How to do this?"
Vladimir please follow the link and download the video showing this being done under SureTrak, any software can do that. This is using SF relationships and an as late as possible constraint, I suppose under "FS0 relationships only" Mike cannot simulate this.
you need not to know Spider Project. It is about potential requirements to any PM software.
Like I need to simulate this situation or to do this analysis. Is it possible?
Spider Project is just an example. I hope that somebody will suggest something really useful for all and we will discuss how it may be achieved.
There is forum for Spider Project users in Russian where people ask questions like "I want to simulate that next activity can start if any one of two preceding activities is finished. How to do this?"
Unfortunately there are few similar discussions here. I hope that this one can provoke to set really hard but still useful tasks.
Best Regards,
Vladimir
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Submitted by Vladimir Liberzon on Sun, 2009-10-04 11:36
I confirm that in Spider Project you can undo any specific action that was done earlier (like 15 actions ago) without undoing next actions.
Maybe I do not understand what is longest path. I just don’t understand the reason to compress the preceding activities if current activity has No Earlier Than constraint. I understand the usefulness of DRAG and we included this in Spider Project. DRAG shows what time each activity adds to the project duration. It can be calculated if to make activity duration equal to zero. Activity may have 10 days duration and being critical but with only 2 days DRAG because there is other subcritical path only 2 days shorter.
Spider Project can show all activities that precede current activity, it also shows driving relationships, it shows floats. You can filter the schedule by float value. You can consider the set of activities that precede current activity as the separate project with its own critical path, DRAG values, etc. It is sufficient for schedule analysis and knowing predecessors to activity with NET constraint does not help at all.
Please explain what I miss.
By the way Spider Project calculates not only activity floats but also assignment floats that may be different.
I supposed Mike did a bias act on the other thread (for he is a Moderator), he just locked it when he feels that hes about to lose. Now he wants private message, thats unfair Mike.
Here, who can challenge Spider? I dont know anything about Spider!
I believe Spider is not the issue! It is longest path; critical path; resource criticality; resource leveling; CPM...etc.
Rafael, Im on your side now, if you want to ban CPM, I can make you a good coffee!
cheers!
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Submitted by Rafael Davila on Sat, 2009-10-03 19:44
Undo is not the same as audit trial, undo are done in backwards sequential order, with audit trial you can see your data entry history and make changes in non sequential order, if you can see what your last 40 or 60 changes were and undo only those you select then it will be a great improvement of what our undo in Primavera Products does, I also understand Primavera undo does not works with resource leveling. If Spider Project can undo specific actions in any order then this is great, please confirm it is not sequential that it can be discretionary in any order you wish.
About Longest Path you for whatever reason might be, you might need to compress or crash the path up to a specific activity, because predecessors can also be tied to other chains, float alone do not identify the driving activities of the particular chain you are investigating. The longest path to the particular activity is not necessarily determined by those predecessors with the lowest amount of float, even when the activity is artificially constrained.
“LONGEST PATH Software extends the theory of Longest Path to every activity in the schedule. Just as with Total Float, every activity in the schedule can be rated by its Longest Path Value. “ Please note Longest Path is not available in any software, Ron Winter provide this without infringing Primavera Copyright in their products, he is enhancing them is a good deal for both. I believe he only works directly with the Database, and then after the changes are done in the database you can see them in P3 until it runs any procedure that recalculates these values.
I don’t have Longest Path Software, I don’t know if it would work with SureTrak P3 files but I believe it can because here the Longest Path Software is dealing directly with the database values.
If someone can develop by their own this functionality is Spider Project, stand to the challenge and extend it to include Resource Critical Path and float plus all other simultaneous constraint sets. That I want to see, Financial Critical Path, I want all these functionality and still able to see driving constraints; predecessors/succesors logic, resources, financial, all.
Best regards,
Rafael
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Submitted by Vladimir Liberzon on Sat, 2009-10-03 16:50
Automatic Audit Trail of Changes in Spider Project is called Protocol of Actions. You can undo any specific action. I don’t remember when this feature was added to Spider Project but many years ago. The user can define how many actions shall be stored (the depth of undo’s). There are no limitations. You can try this feature in Spider Demo.
Expected finish Constraint will be shown if to compare forward and backward schedules. You can do it at any moment if necessary.
Best Regards,
Vladimir
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Submitted by Vladimir Liberzon on Sat, 2009-10-03 16:06
I have read about the Longest Path and did ot understand its value. If activity is restricted by No Enarlier Than constraint what driving relationships will give us? Why it is necessary to know longest path if you know activities with the minimal float.
If it is necessary to know the path from the beginning determine the activity that has no predecessors with the minimal float and filter the schedule showing only those activities that have floats equal or less. Or just define that activities with the float equal or less than ... are critical and you will see the longest path in red.
If you see the difference then explain it to me.
Vladimir
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Submitted by Rafael Davila on Fri, 2009-10-02 18:53
Thanks for your response about how to model crane use; you got it right this was my question.
I am not familiar with the use of consumable resources as Primavera SureTrak or P3 do not provide for these. I believe that Micro Planner had the concept of consumable resources; to me it seems similar to your material resource, just another name, please confirm.
I got the following functionalities missing from our software would like you to tell me if they or equivalent are available in Spider Project.
3)Expected Finish Constraint: this constraint calculates Remaining duration automatically between updates as the difference between the Expected Finish Constraint and the Data Date. Not a must have but handy.
Best regards,
Rafael
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Submitted by Vladimir Liberzon on Fri, 2009-10-02 17:02
it is not necessary to level costs if you just want to know project cash flow. If you can work without financing then it is OK and you will know how much money you will spend until next payment.
But if your money are limited then you will depend on project income and it is nice to know project schedule that is adjusted to your financial capabilities.
When Russian Ministry of Defence planned large 10 years program they found that program cost was very uneven - expenses for one year were several times more than for another year, etc. So the program schedule was unrealistic because it will not financed this way. So they input expected limits of program financing per year and got new schedule that was approved.
Mike, computers shall help us to decide. Play what if - computers calculate faster and can try much more different options than people.
Hi Rafael,
Storage capacity can be simulated the same way. Actually we have successful experience of Just in time construction management in the middle of downtown. Project lasted one year and a half and was finished two days later than was planned in the initial schedule.
Do you mean cranes by hoisting facilities? My English is not very good, so sometimes I will ask for the explanations.
The crane is one of the project resources. And usually it is critical resource especially in the construction in the middle of downtown. We simulate its work as follows:
1) Estimate the average number of lifts in one shift,
2) Estimate the number of lifts necessary for different works (activities) during one shift,
3) Divide this number by total number and multiply by 100.
Now you know the workload of the crane on your activity.
Of course there are other activities where crane is 100% assigned because it does not lift but holds something and will not do other works in parallel.
I know queueing theory and applied it to some tasks in the past, but for project scheduling it is not necessary. I know only one practical task where it shall be applied: determination of the optimal number of trucks that shall serve the excavators in earth moving works. But it shall be done before scheduling.
Next week I will return from Germany and will answer faster.
Best Regards,
Vladimir
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Submitted by Vladimir Liberzon on Sat, 2011-06-11 18:24
“If financing schedule is a part of your project schedule model then Spider Project will calculate project schedule taking into account financial limitations and delaying activities when there are no money to proceed.”
You are thinking out of the box. With my mindset of a general contractor, not of a developer I was wondering on the application of this functionality. Yes I accept financial constaints as real constraints, and find your approach very clever.
Let’s move to the issues on “materials” constraints. You mentioned earlier in another thread about the use of material resources as to constraint your schedule under limited available work space. But can this also be used as a way to model limited storage space at the jobsite? Let say a job in the middle of downtown or an offshore rig.
And what about limits on hoisting facilities? This is a queuing or “waiting line” problem., I have no idea on how to model that into a CPM schedule but into a GPSS (Gen. Purpose Symulation System) or the like.
when I wrote about applying priorities I meant priorities of certain activities or projects. When the scheduler receives automatic scheduling result he/she can try to improve it applying user defined activity/phase priorities (just numbers).
Spider does not have random scheduling and does not apply different priorities selecting the best result. Our algorithms were created for scheduling of very large projects (with hundreds of thousands activities) and shall be very fast to be practical. Both sample schedules that you proposed were calculated in less than one second time.
Applying random heuristics can produce good schedules but is not ptactical in project management. Project life cycle can be measured by years and the schedule is revised at least each week. It is necessary to be able to get the same or similar schedule after minor changes. Random priorities are hard to repeat.
Thank you for the benchmark reference. Comparing Spider schedules with optimal we can find the ways for further improvements.
I am curious about the results produced for the same schedules by production scheduling programs. I know PM software market but did not work with MES systems.
Best Regards,
Vladimir
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Submitted by George Mejtsky on Sat, 2011-06-11 05:27
Great! Thank you for your time and effort. How long was the calculation time? It looks like the second gold medal for Spider. When you have time, can you try to improve this schedule by applying priorities? Can you describe the process of applying priorities? As I understand, you select a priority or set of priorities and calculate the schedule, and then you select a different priority (rule, heuristic) and calculate a new schedule, etc. You repeatedly calculate schedules with different priorities, and then you select the best schedule found. Is this process the same in Spider?
In Spider, do you have some random priority (random heuristic) which would select randomly? I would like to know the length of the random schedule or an average schedule. If we know the average/random schedule then we could compare our best found schedule with the random schedule. We might find that our schedules based on priorities might not be better than the random schedule. I hope it is not the case.
The first production problem (6 projects and 6 resources, 6x6) is the smallest and one of the easiest instances found in the standard job shop scheduling benchmark set. This problem is called FT06 and has optimum makespan 55. Spider found the schedule with makespan 56 which is only 2% longer than the optimal schedule. Frankly, it is not very far from the optimum indeed.
The second production problem (10x10) is probably the most famous job shop scheduling problem, called FT10. FT10 has optimum makespan 930 which is very difficult to find. Spider found the schedule with makespan 1016 (16 x 60 + 56) which is 9% longer than the optimal schedule. So there is enough space for improvement here. How much can you improve it? I think it is a very good schedule for the default "out of the box" solution. Can anybody find a better default "out of the box" schedule with a different software? I doubt.
In real world projects (large and complex), the optimum schedule is not reachable. Therefore, we do not know how far our schedule is from the optimum schedule. However, if we can get a random/average schedule then we can compare our schedule with it to make sure that our schedule is better than the random one, hopefully. That’s why, I propose to include the random priority rule in Spider, if it is missing.
Best Regards,
George
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Submitted by Vladimir Liberzon on Fri, 2011-06-10 22:48
Thanks for trying backward scheduling. I kind of agree with Rafael that “The bigger the schedule the more you will notice the difference between Spider and the rest.” So here is a bigger production problem with 10 projects and 10 resources to show a bigger difference, I hope.
we do not make our optimization algorithms public. It is rather complex iterative heuristics. We did not compare Spider schedules with Preactor's. This information we got from our customers in Brazil.
I tried backward scheduling but the result was not improved. It is possible to try options applying user defined priorities but it is time consuming and hard when the schedules consist of many thousands activities. We tried to make the default schedule as close to optimal as possible with very limited number of iterations. Resource scheduling shall be very fast to provide good schedules at the start of each shift and the schedules where Spider is used are usually large.
Thanks for your information about activity duration in project scheduling. I am still learning and learning. Raf selected Optimization Plus method on the Resource Constrained Scheduling Options form. How does the method optimize the schedule? Raf mentioned that perhaps the method searches some prioritization rules under several layers (iterative heuristics?). By the way, why Spider schedules are much shorter than Preactor schedules?
Rafael,
Can you run my problem (6x6) again and this time with Backward Direction (instead of Forward) set on the Resource Constrained Scheduling Options form? You might find a shorter schedule with 55 minutes total duration, I hope.
It would be very useful if somebody would solve Vladimir and my problems by other project management software, like Mike with Asta. So we could compare them by quality of resource allocating.
Best Regards,
George
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Submitted by Vladimir Liberzon on Fri, 2011-06-10 04:42
usually initial information for such projects is not activity durations, but volumes (quantities) of work to be done on activities and productivities of assigned resources. Activity duration is calculated as the ratio of volume of work and total productivity of all assigned resources.
You can also assign skills necessary for doing the job. If resources that have necessary skill are known Spider will select resources to be assigned basing on default or user defined priorities and resource availabilities. In this case activity durations are not known before scheduling because different resources have different productivities and durations are calculated in the process of project scheduling when assignments are selected.
Best Regards,
Vladimir
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Submitted by Rafael Davila on Fri, 2011-06-10 03:17
It takes fractions of a second, perhaps faster than the time it takes your sight to follow the cursor. The software is designed to work with thousands of activities per job and a few jobs opened at the same time.
It was done selecting the Optimization algorithm, is 100% automatic. The others not necessarily will provide you with a shorter schedule, no matter which prioritization rules you use. The bigger the schedule the more you will notice the difference between Spider and the rest.
At times it is better to use the other methods as to have some control, especially when using "Apply activity prioritieas" and "Apply phase priorities" in addition to other selected on the Priority selection box. Then when in trouble go to full optimization, here the Priority selection box will be dimmed and the software will look for full optimization without regard to a pre-defined priority, perhaps in Optimization modes it searches some prioritization rules under several layers, if this makes sense.
The following screen will show you the resource leveling options screen.
You can download the Spider File for your use with the demo so you can explore it yourself and find out if there is any error.
If you do not work multiple jobs linked together or sharing resources, each job thousands of activities Vladimir might help you select the best option for your needs, it is a scalable product.
Best regards,
Rafael
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Submitted by George Mejtsky on Fri, 2011-06-10 01:14
Wonderful! Congratulations! It is a very good schedule. It looks like the gold medal will go to the Spider team. If the Asta PowerProject team, or another team, does not find a shorter schedule, gold will go to Rafael for the Spider team.
Rafael, did you produce the great schedule out of the box (without applying user defined priorities)? How long was the calculation time?
Anyway, I must thank you for your time and effort.
Cheers,
George
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Submitted by Rafael Davila on Fri, 2011-06-10 00:05
Thank you for your detailed response and your time with the problem (4 projects and 3 resources). Why Spider schedules are much shorter than Preactor schedules? I am trying to find software which is better than others, producing shorter schedules than competitors can produce. I do not care about optimal schedules, I only care about just better schedules than others can produce. How do iterative heuristics of Spider find a good solution in this problem of yours?
Mike, thanks for participation in this discussion. Is your schedule shorter than 51 minutes?
Vladimir, can you try another problem with 6 projects and 6 resources? No tool change time (set-up time) is included, and each resource has capacity 1 (quantity 1). To describe the problem, I will use a short notation: resource number/duration. For example, 2/1 means the operation needs resource number 2 for 1 minute.
--------
Problem (6 projects, 6 resources):
P1: 2/1, 6/3, 1/6, 3/7, 5/3, 4/6.
P2: 1/8, 2/5, 4/10, 5/10, 6/10, 3/4.
P3: 2/5, 3/4, 5/8, 6/9, 1/1, 4/7.
P4: 1/5, 6/5, 2/5, 3/3, 4/8, 5/9.
P5: 2/9, 1/3, 4/5, 5/4, 6/3, 3/1.
P6: 1/3, 3/3, 5/9, 6/10, 4/4, 2/1.
---------
Read the first line like this: Project P1: the first operation needs resource R2 for 1 minute, the second operation needs resource R6 for 3 minutes, then operation 3 needs resource R1 for 6 minutes, etc. Notice that each project uses each resource but in a different sequence. In the Vladimir problem, all 4 projects have the same sequence of resources (R1, R2, R3).
Mike, can Asta PowerProject find a shorter schedule than Spider Project?
It sounds like the Olympic Games in Project Management software.
I did not mean George example but general production scheduling.
If I don't know the next work then I don't know necessary tools and what time is necessary for tools adjustment. So I cannot add changeover activity because don't know what work will be next and what time will it take. It is not actual in project management but may be critical in production scheduling. I think that we will add this feature to Spider since we have more and more customers in manufacturing.
I did not see any item about changing tools in Georges thread - just applying Resource R1 to a number of different tasks in different projects.
That is the same as allocating Crew 1 to different sections of a pipeline.
If there is to be a time required for tool change over then that could be done with a simple task set between changeover tasks or alternativel a lead time on the link if the calendars are compatible.
Best regards
Mike T.
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Submitted by Vladimir Liberzon on Thu, 2011-06-09 08:44
Spider Project is used for production scheduling in Russia, Ukraine and Brazil. Recently I received a letter from Brazil where it was written that Spider is used for production scheduling instead of Preactor because Spider schedules are much shorter.
But Spider still does not model time necessary for changing the tools when there is a need to do different type of job. This is serious restriction if these times are large.
You described famous NP-complete problem and Spider does not guarantee the optimal solution but its iterative heuristics finds the solution that will be close to optimal. I added fourth project (machine) to the example below to show what Spider will do solving your task.
Mike, I am curious if Asta will produce the same (or better) schedule for the same problem out of the box (without applying user defined priorities). Please enter the same data into Asta and show us the result. Regards,
I respect you, and I agree with your postings. In fact, I cannot find even one sentence where I would not agree with you. You proposed to suggest hard tasks so I will try my luck. I am coming from production scheduling field, and I wonder whether your Spider Project software can solve some of shop scheduling problems. I will describe such problems by project scheduling terms.
I have several projects: The first project P1 starts with activity P1A1. The activity P1A1 requires resource R1 for p1a1r1 minutes, and then the next P1 activity A2 requires resource R2 for p1a2r2 minutes. The third activity A3 of P1 requires resource R3 for p1a3r3 minutes, etc. The second project P2 starts with activity P2A1 requiring resource R1 for p2a1r1 minutes, and then the next P2 activity A2 requires resource R2 for p2a2r2 minutes, etc. The third project P3 starts with activity P3A1 requiring resource R1 for p3a1r1, etc. So each project has a sequence of activities and each activity requires a resource for a fix time. Each resource Ri can be assigned to only one activity (resource capacity is 1). This is a resource allocation problem. The question is how to allocate each resource so that to minimize the overall completion time of all projects.
I guess Spider Project software can solve this type of problems. Can you tell me if and how it can be done in Spider?
Best Regards,
George
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Submitted by Rafael Davila on Wed, 2010-04-28 23:28
Yes, it is a useful visual report, but my point is that it shines in linear projects.
And while contrary to other linear diagram tools, in Spider all the PDM functionalities are also available. The PDM metrics matter as much or even more, still if a linear job, the Graph is just a representation.
Best Regards,
Rafael
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Submitted by Vladimir Liberzon on Wed, 2010-04-28 22:29
if you will download Demo version of Spider Project from http://www.spiderproject.ru/demo_e.php you will find there sample project that includes construction part (a small part of the resl project), financing, and future profits.
In this project you will find multi-resources (crews) assigned to construction activities, activity durations that are calculated basing on their volumes of work and assigned resources productivities, cost components and cost centers, cash flows that includes expenses and financing, expenses and incomes that are calculated with cost discounting, materials that are assigned per work volume units, resources that work in shifts. In this project you can try cost and material levelling.
It is small part of many unique Spider Project features but you will not be able to repeat this project using other softwares including P6.
Spider Project optimizes resource constrained schedules. Recently Rafael uploaded small and simple project but P6 produced optimal schedule (the same as the schedule produced by Spider Project) only after manual assignment of activity priorities. Impossible in large projects. And in many real projects the difference of schedule durations is huge.
I can add skill scheduling, trend analysis, etc.
If you ask about some reports I suggest to look at Linear Diagram - it is Time-Location Chart that is one of many projectt reports.
If you want to see something specific please ask.
This thread was created for challenging Spider Project - I am still waiting for hard tasks. If you need something that other PM software does not do, ask if Spider Project can do it. Two options - I can explain how Spider does it, or you will suggest Spider Project improvement.
Best Regards,
Vladimir
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Submitted by Rafael Davila on Wed, 2010-04-28 21:31
You sound well conversant with both spider and primavera...can you attach a layout of spider that you think P5 cant produce. Thanks please do it at your convinience.
I personally request Russian papers or presentations if there are any. My Russian is not good enough for that kind of stuff but I can make them translated at my work easily.
Regards,
Safak VURAL
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Submitted by Vladimir Liberzon on Sat, 2010-02-13 15:23
I am sorry that there are few Spider papers and presentations in English. Don’t forget that it is Russian software. The documentation that is created by Russian corporations is in Russian and Brazilians publish their papers in Portuguese.
Spider site contains papers and presentations mostly made at different PMI events. At these presentations I talked about the methods that we use trying to avoid mentioning Spider. Spider Project was and is used for management of many oil&gas construction projects in Russia, Ukraine, Belarus. Examples; Caspian Pipeline, Blue Stream, Nord Stream, East Siberia – Pacific Ocean, and other pipelines, development of Bovanenkovo Gas Field.
Best Regards,
Vladimir
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Submitted by Rafael Davila on Sat, 2010-02-13 10:07
In Spider Project you can run Scripts from outside Spider so you can have access to all the power Reference Book provides. If your software can access text files then it can communicate with Spider Project, if I understood correctly what Vladimir once mentioned in one of his postings.
Perhaps it is not a good idea to have a direct link to the database fields as this can corrupt integrity of the data, Reference Books provides the link. Field relationships in CPM are not as simple as relationships within a database.
I do not have such a requirement in my jobs but Spider can provides for the most demanding requirements, on my part you are welcomed with your questions, I believe this kind of questions were missing and your postings will add value to the discussion.
If I am right maybe in a future we will be exchanging script templates to communicate with Oracle/Primavera/Microsoft/SAP/....
First of all I want to congratulate you for the battle you continue to make people hear you. I wish you to continue your way and conquer more castles in project controls territory.
I am trying to follow this thread with playing in your demo. Everything seems so perfect user friendly and solution oriented in software. Personally ASTA – Power Project seems good scheduling software also. But the ORACLE® and PRIMAVERA® are offering some other aspects as well. Also all my clients are commitetd to them. In many projects I touch or hear (from colleagues etc.) cost control - oracle rdb, estimating and quantity surveying sql rdb, HR and personnel time recording oracle and sql rdb, QA/QC sql rdb ……. List can be longer. Data collecting is becoming easier and IT works is becoming user-friendly everyday. SPIDER® has to fight with these kinds of integrated packages in the market also due to availability of direct integration for PRIMAVERA® products with that kind of databases.
Can I challenge SPIDER® team not with software with studies, papers, procedures etc. If you check all major construction companies in OIL&GAS almost all their project control documentation based on duration based CPM where majority of them referencing PRIMAVERA® directly.
Can you provide more documents about projects which used SPIDER® and Critical Chain Project Management (Like Urucu-Manaus Gas Pipeline)? It is not easy to find papers, studies etc. supporting Critical Chain. Can you reference papers? Can you create a package that the Project Controls for Critical Chain approach with all main and support processes including inputs, outputs, responsible items, customers, where you can include SPIDER® in one or more of this processes. I checked all publications SPIDER® web page but I cannot find anything which is answering the questions above. If there are academic references you can provide I will be happy also. I will try to access them from my university library in my vacation times at my hometown.
Regards,
Safak Vural
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Submitted by Rafael Davila on Sun, 2010-01-24 18:40
You got it very right; my question was about scalability and transfer of resource definitions.
The great thing about it is that scaling is defined at the activity level so when scaling your fragments only scalable activities will be scaled. If you have a fragment for mat foundations, you would transfer several activities whose duration will depend on the scale but others will not be changed such as concrete curing.
Maybe you cannot say all activities will either be fully scalable or not scalable, a few will fall in between. I would dare to say over 95% will be covered and the remaining with a simple adjustment can be handled. Hey you are transferring even resource definitions.
Please don’t complicate fragments, keep is as simple as it is, cannot get any better.
Best regards,
Rafael
Member for
24 years 8 months
Member for24 years9 months
Submitted by Vladimir Liberzon on Sun, 2010-01-24 18:08
I dont know software packages that have similar functions.
This is the way we create complex project models.
Fragments describe typical work packages for certain work quantity (1km, 10m3, etc.). Inserting the fragment project planner defines the real volume of work at the certain work package and fragment data will be adjusted automatically.
With fragment library it is easy to create large project models:
Project Planner creates WBS, then inserts project fragments at work packages level, then creates links between activities of different work packages. Everything else is already there - resources, costs, calendars.
Fragment Library is the main element of the corporate PM system.
Best Regards,
Vladimir
Member for
21 years 8 months
Member for21 years8 months
Submitted by Rafael Davila on Sun, 2010-01-24 17:39
Thanks you for your briefing on the application of fragments.
…”For repeating sets of activities we suggest to use the typical fragments library that consists of small projects that model typical sets of works. You can use insert other projects as the new phases. This is the way we use working with the fragments. The software asks what to do with activity codes and volumes. Activities may be scalable or not (look at activity properties). If scalable then their volumes, durations, etc. will be multiplied by the user defined number”.
I noted that even resources definition is transferred so if new resources are required these will also be transferred.
This feature of being able to scale the fragments is something I have never seen before. With Primavera SureTrak I did not even had the basic functionalities of fragments. Do you know if such “scalable” and transfer of resource definitions are features available in other software?
Member for
21 years 8 monthsRE: Let’s Challenge SPIDER
Vladimir,
It will take me some time to analyze your question, although it still continue to move the activities there is a possibility of other issues not being considered, I am also finding issues on the calculated total float for the driver of CCC, this is another issue. If latter you can e-mail me a P3 file then it will be easier for me to model what you are observing.
I was also thinking in the possibility of using consumable resources. Using negative consumption the predecessors can replenish the resource from 0, the successor activity will not be able to start until you have the required resources, but I do not have this functionality as to explore it. I was also thinking about the activity consuming the resource but at the same time replenishing it at the same rate as to prevent the resource from being consumed and still being able to be replenished by other activities and used for constraining the start of other activites.
Do you have another idea?
Best regards,
Rafael
Member for
24 years 8 monthsRE: Let’s Challenge SPIDER
Rafael,
what if your activities are in the middle of some schedule?
Then ALAP will not work.
Besides, SF means that AAA and BBB will finish after CCC starts. It means that CCC can start early - it may happen as the result of resource levelling.
Please clarify.
Best Regards,
Vladimir
Member for
21 years 8 monthsRE: Let’s Challenge SPIDER
Vladimir,
Ironically activity CCC is set to be the predecessor, the links are the following
CCC --> SF0 --> AAA
CCC --> SF0 --> BBB
CCC has a “As late as possible” Float Constraint
I uploaded the P3 file under the following link so anyone can download it and explore it, because I am using SureTrak you will have to adjust your Layout.
http://rapidshare.com/files/288646383/FIFO.zip
I am still wondering how to schedule for the activity to start as soon as any three out of a set of 10 finishes. Real life is not as easy as FS0 only.
Best regards,
Rafael
Member for
24 years 8 monthsRE: Let’s Challenge SPIDER
Hi Rafael,
I mentioned this task just as an example of questions that are asked in our forum. I am glad that Suretrak can do it though I did not understand about SF relationship with ALAP constraint.
Hi Carlos,
Spider Project has "jump to predecessor/succesor" function and can export/import to MS Project and P6. It has no direct export to P3 but exports to mpx that P3 understands.
Besides it exports/imports to text and databases. Any Spider table can be exported to Excel and vice versa.
Spider shows links of current activity in the diagram. Clicking on the preceding or succeding activity you will see its properties including links, Then you can click on another preceding or succeding activity and again see its properties (duration, volume, assignments, links, etc.).
Best Regards,
Vladimir
Member for
16 years 5 monthsRE: Let’s Challenge SPIDER
Can Spider import/export to MS project or Primavera format? Power Project can, it is very useful since these two are many industries standard.
Member for
16 years 5 monthsRE: Let’s Challenge SPIDER
Hi. Has Spider project that useful for everything "jump to predecessor/succesor" button P3 has? In 2 clics, it takes you to the predecessors of an activity. It is very useful, I dont know why it is not a feature of modern software, they seem to be focusing in making things more and more complicated instead of making common tasks more easygoing.
This is what I mean, I can get the driving sequence of an activity just by following its driving predecessors:
http://screenr.com/ZhH
Member for
21 years 8 monthsGeorge,Sequential application
George,
Sequential application of Optimization Plus and then Advanced using Super Float as Priority will yield better results, and this is without using activity priority. Don't ask me, trial and error, brute force, took me less than 2 minutes though.
http://www.youtube.com/watch?v=KqPzTLX_Gb0
What stands out is that even a schedule known to be difficult to optimize is not that far from optimum with Spider Project Optimization Plus out of the box. I would dare to say on real life jobs Spider will be between 6% and 0% of optimal with an average of 3%, with a distribution close to 3%.
No way you can consistently get there using preferential links as to mimic true resource leveling.
Believe me I have seen software that can go as far as 40% over Spider, say 43% over optimal, and this is unacceptable.
In schedules where partial assignments are allowed Spider stands out as it can even allocate for variable partial assignment. Partial assignments is the order of the day in construction schedules as well as in architectural design schedules where you have some crews or individual resources assigned to work on several long duration activities the same day.
Variable assignment is a refinement over fixed partial assignment that will make a huge difference when allowed.
Spider Demo is limited to 40 activities but if you want to explore the 10x10 schedule maybe using the Free Spider viewer you can explore the files. You can download the file from the following link.
http://www.mediafire.com/?65yqw27jtx48ys4
Regards,
Rafael
PS. The calculation time is always at a blink of the eye, as soon as resource leveling icon is clicked as seen on the video clip.
Member for
21 years 8 monthsRE: Let’s Challenge SPIDER
"You can consider the set of activities that precede current activity as the separate project with its own critical path, DRAG values, etc."
Seems like the equivalent of Longest Path, this is useful and relevant functionality.
"I want to simulate that next activity can start if any one of two preceding activities is finished. How to do this?"
Vladimir please follow the link and download the video showing this being done under SureTrak, any software can do that. This is using SF relationships and an as late as possible constraint, I suppose under "FS0 relationships only" Mike cannot simulate this.
http://rapidshare.com/files/288615256/FIFO.avi
Best regards,
Rafael
Member for
24 years 8 monthsRE: Let’s Challenge SPIDER
Hi Anoon,
you need not to know Spider Project. It is about potential requirements to any PM software.
Like I need to simulate this situation or to do this analysis. Is it possible?
Spider Project is just an example. I hope that somebody will suggest something really useful for all and we will discuss how it may be achieved.
There is forum for Spider Project users in Russian where people ask questions like "I want to simulate that next activity can start if any one of two preceding activities is finished. How to do this?"
Unfortunately there are few similar discussions here. I hope that this one can provoke to set really hard but still useful tasks.
Best Regards,
Vladimir
Member for
24 years 8 monthsRE: Let’s Challenge SPIDER
Hi Rafael,
I confirm that in Spider Project you can undo any specific action that was done earlier (like 15 actions ago) without undoing next actions.
Maybe I do not understand what is longest path. I just don’t understand the reason to compress the preceding activities if current activity has No Earlier Than constraint. I understand the usefulness of DRAG and we included this in Spider Project. DRAG shows what time each activity adds to the project duration. It can be calculated if to make activity duration equal to zero. Activity may have 10 days duration and being critical but with only 2 days DRAG because there is other subcritical path only 2 days shorter.
Spider Project can show all activities that precede current activity, it also shows driving relationships, it shows floats. You can filter the schedule by float value. You can consider the set of activities that precede current activity as the separate project with its own critical path, DRAG values, etc. It is sufficient for schedule analysis and knowing predecessors to activity with NET constraint does not help at all.
Please explain what I miss.
By the way Spider Project calculates not only activity floats but also assignment floats that may be different.
Best Regards,
Vladimir
Member for
19 years 10 monthsRE: Let’s Challenge SPIDER
Hi Anoon
Whats the point of having a bit of power if you cant abuse it now and then?
Best regards
Mike Testro
Member for
19 years 1 monthRE: Let’s Challenge SPIDER
All,
I supposed Mike did a bias act on the other thread (for he is a Moderator), he just locked it when he feels that hes about to lose. Now he wants private message, thats unfair Mike.
Here, who can challenge Spider? I dont know anything about Spider!
I believe Spider is not the issue! It is longest path; critical path; resource criticality; resource leveling; CPM...etc.
Rafael, Im on your side now, if you want to ban CPM, I can make you a good coffee!
cheers!
Member for
21 years 8 monthsRE: Let’s Challenge SPIDER
Vladimir
Undo is not the same as audit trial, undo are done in backwards sequential order, with audit trial you can see your data entry history and make changes in non sequential order, if you can see what your last 40 or 60 changes were and undo only those you select then it will be a great improvement of what our undo in Primavera Products does, I also understand Primavera undo does not works with resource leveling. If Spider Project can undo specific actions in any order then this is great, please confirm it is not sequential that it can be discretionary in any order you wish.
About Longest Path you for whatever reason might be, you might need to compress or crash the path up to a specific activity, because predecessors can also be tied to other chains, float alone do not identify the driving activities of the particular chain you are investigating. The longest path to the particular activity is not necessarily determined by those predecessors with the lowest amount of float, even when the activity is artificially constrained.
http://scheduleanalyzer.com/sa_long.htm
http://scheduleanalyzer.com/sa_long_theory.htm
“LONGEST PATH Software extends the theory of Longest Path to every activity in the schedule. Just as with Total Float, every activity in the schedule can be rated by its Longest Path Value. “ Please note Longest Path is not available in any software, Ron Winter provide this without infringing Primavera Copyright in their products, he is enhancing them is a good deal for both. I believe he only works directly with the Database, and then after the changes are done in the database you can see them in P3 until it runs any procedure that recalculates these values.
I don’t have Longest Path Software, I don’t know if it would work with SureTrak P3 files but I believe it can because here the Longest Path Software is dealing directly with the database values.
If someone can develop by their own this functionality is Spider Project, stand to the challenge and extend it to include Resource Critical Path and float plus all other simultaneous constraint sets. That I want to see, Financial Critical Path, I want all these functionality and still able to see driving constraints; predecessors/succesors logic, resources, financial, all.
Best regards,
Rafael
Member for
24 years 8 monthsRE: Let’s Challenge SPIDER
Rafael,
Automatic Audit Trail of Changes in Spider Project is called Protocol of Actions. You can undo any specific action. I don’t remember when this feature was added to Spider Project but many years ago. The user can define how many actions shall be stored (the depth of undo’s). There are no limitations. You can try this feature in Spider Demo.
Expected finish Constraint will be shown if to compare forward and backward schedules. You can do it at any moment if necessary.
Best Regards,
Vladimir
Member for
24 years 8 monthsRE: Let’s Challenge SPIDER
Rafael,
I have read about the Longest Path and did ot understand its value. If activity is restricted by No Enarlier Than constraint what driving relationships will give us? Why it is necessary to know longest path if you know activities with the minimal float.
If it is necessary to know the path from the beginning determine the activity that has no predecessors with the minimal float and filter the schedule showing only those activities that have floats equal or less. Or just define that activities with the float equal or less than ... are critical and you will see the longest path in red.
If you see the difference then explain it to me.
Vladimir
Member for
21 years 8 monthsRE: Let’s Challenge SPIDER
Vladimir,
Thanks for your response about how to model crane use; you got it right this was my question.
I am not familiar with the use of consumable resources as Primavera SureTrak or P3 do not provide for these. I believe that Micro Planner had the concept of consumable resources; to me it seems similar to your material resource, just another name, please confirm.
I got the following functionalities missing from our software would like you to tell me if they or equivalent are available in Spider Project.
1)Automatic Audit Trail of Changes: http://www.ronwinterconsulting.com/Making_CPM_Transparent.pdf
2)Longest Path Value:
http://www.ronwinterconsulting.com/Longest_Path_Value.pdf
3)Expected Finish Constraint: this constraint calculates Remaining duration automatically between updates as the difference between the Expected Finish Constraint and the Data Date. Not a must have but handy.
Best regards,
Rafael
Member for
24 years 8 monthsRE: Let’s Challenge SPIDER
Hi Mike,
it is not necessary to level costs if you just want to know project cash flow. If you can work without financing then it is OK and you will know how much money you will spend until next payment.
But if your money are limited then you will depend on project income and it is nice to know project schedule that is adjusted to your financial capabilities.
When Russian Ministry of Defence planned large 10 years program they found that program cost was very uneven - expenses for one year were several times more than for another year, etc. So the program schedule was unrealistic because it will not financed this way. So they input expected limits of program financing per year and got new schedule that was approved.
Mike, computers shall help us to decide. Play what if - computers calculate faster and can try much more different options than people.
Hi Rafael,
Storage capacity can be simulated the same way. Actually we have successful experience of Just in time construction management in the middle of downtown. Project lasted one year and a half and was finished two days later than was planned in the initial schedule.
Do you mean cranes by hoisting facilities? My English is not very good, so sometimes I will ask for the explanations.
The crane is one of the project resources. And usually it is critical resource especially in the construction in the middle of downtown. We simulate its work as follows:
1) Estimate the average number of lifts in one shift,
2) Estimate the number of lifts necessary for different works (activities) during one shift,
3) Divide this number by total number and multiply by 100.
Now you know the workload of the crane on your activity.
Of course there are other activities where crane is 100% assigned because it does not lift but holds something and will not do other works in parallel.
I know queueing theory and applied it to some tasks in the past, but for project scheduling it is not necessary. I know only one practical task where it shall be applied: determination of the optimal number of trucks that shall serve the excavators in earth moving works. But it shall be done before scheduling.
Next week I will return from Germany and will answer faster.
Best Regards,
Vladimir
Member for
24 years 8 monthsRafael,it is interesting that
Rafael,
it is interesting that the sequence Optimization and then Advanced Super Float saves 1 more minute:
Thank you and Best Regards,
Vladimir
Member for
21 years 8 monthsRE: Let’s Challenge SPIDER
Vladimir,
“If financing schedule is a part of your project schedule model then Spider Project will calculate project schedule taking into account financial limitations and delaying activities when there are no money to proceed.”
You are thinking out of the box. With my mindset of a general contractor, not of a developer I was wondering on the application of this functionality. Yes I accept financial constaints as real constraints, and find your approach very clever.
Let’s move to the issues on “materials” constraints. You mentioned earlier in another thread about the use of material resources as to constraint your schedule under limited available work space. But can this also be used as a way to model limited storage space at the jobsite? Let say a job in the middle of downtown or an offshore rig.
And what about limits on hoisting facilities? This is a queuing or “waiting line” problem., I have no idea on how to model that into a CPM schedule but into a GPSS (Gen. Purpose Symulation System) or the like.
Best regards,
Rafael
Member for
19 years 10 monthsRE: Let’s Challenge SPIDER
Hi Vladimir
Most software has a cost v income function but will not stop the programme if the preset parameters are exceeded.
That is left to the judgement of the manager assisted by his planners reports.
I do not like the idea of computers making decisions for us.
Best regards
Mike Testro
Member for
24 years 8 monthsGeorge,when I wrote about
George,
when I wrote about applying priorities I meant priorities of certain activities or projects. When the scheduler receives automatic scheduling result he/she can try to improve it applying user defined activity/phase priorities (just numbers).
Spider does not have random scheduling and does not apply different priorities selecting the best result. Our algorithms were created for scheduling of very large projects (with hundreds of thousands activities) and shall be very fast to be practical. Both sample schedules that you proposed were calculated in less than one second time.
Applying random heuristics can produce good schedules but is not ptactical in project management. Project life cycle can be measured by years and the schedule is revised at least each week. It is necessary to be able to get the same or similar schedule after minor changes. Random priorities are hard to repeat.
Thank you for the benchmark reference. Comparing Spider schedules with optimal we can find the ways for further improvements.
I am curious about the results produced for the same schedules by production scheduling programs. I know PM software market but did not work with MES systems.
Best Regards,
Vladimir
Member for
14 years 4 monthsVladimir,Great! Thank you for
Vladimir,
Great! Thank you for your time and effort. How long was the calculation time? It looks like the second gold medal for Spider. When you have time, can you try to improve this schedule by applying priorities? Can you describe the process of applying priorities? As I understand, you select a priority or set of priorities and calculate the schedule, and then you select a different priority (rule, heuristic) and calculate a new schedule, etc. You repeatedly calculate schedules with different priorities, and then you select the best schedule found. Is this process the same in Spider?
In Spider, do you have some random priority (random heuristic) which would select randomly? I would like to know the length of the random schedule or an average schedule. If we know the average/random schedule then we could compare our best found schedule with the random schedule. We might find that our schedules based on priorities might not be better than the random schedule. I hope it is not the case.
The first production problem (6 projects and 6 resources, 6x6) is the smallest and one of the easiest instances found in the standard job shop scheduling benchmark set. This problem is called FT06 and has optimum makespan 55. Spider found the schedule with makespan 56 which is only 2% longer than the optimal schedule. Frankly, it is not very far from the optimum indeed.
The second production problem (10x10) is probably the most famous job shop scheduling problem, called FT10. FT10 has optimum makespan 930 which is very difficult to find. Spider found the schedule with makespan 1016 (16 x 60 + 56) which is 9% longer than the optimal schedule. So there is enough space for improvement here. How much can you improve it? I think it is a very good schedule for the default "out of the box" solution. Can anybody find a better default "out of the box" schedule with a different software? I doubt.
I hope I made no errors in defining FT06 and FT10. You can find all the benchmarks defined in http://www.eis.uva.es/elena/Elena%20Perez%20Vazquez_archivos/files_optimaJSSP/jobshop1.txt. An additional information about the benchmarks is in http://www.eis.uva.es/elena/JSSP/index.htm.
In real world projects (large and complex), the optimum schedule is not reachable. Therefore, we do not know how far our schedule is from the optimum schedule. However, if we can get a random/average schedule then we can compare our schedule with it to make sure that our schedule is better than the random one, hopefully. That’s why, I propose to include the random priority rule in Spider, if it is missing.
Best Regards,
George
Member for
24 years 8 monthsGeorge,Spider default
George,
Spider default schedule for this project lasts 16 hours and 56 minutes
Resources are used as follows
Best Regards,
Vladimir
Member for
14 years 4 monthsVladimir,Thanks for trying
Vladimir,
Thanks for trying backward scheduling. I kind of agree with Rafael that “The bigger the schedule the more you will notice the difference between Spider and the rest.” So here is a bigger production problem with 10 projects and 10 resources to show a bigger difference, I hope.
----------------------
Problem (10 projects, 10 resources):
P1: 10/29, 1/78, 2/9, 3/36, 4/49, 5/11, 6/62, 7/56, 8/44, 9/21.
P2: 10/43, 2/90, 4/75, 9/11, 3/69, 1/28, 6/46, 5/46, 7/72, 8/30.
P3: 1/91, 10/85, 3/39, 2/74, 8/90, 5/10, 7/12, 6/89, 9/45, 4/33.
P4: 1/81, 2/95, 10/71, 4/99, 6/9, 8/52, 7/85, 3/98, 9/22, 5/43.
P5: 2/14, 10/6, 1/22, 5/61, 3/26, 4/69, 8/21, 7/49, 9/72, 6/53.
P6: 2/84, 1/2, 5/52, 3/95, 8/48, 9/72, 10/47, 6/65, 4/6, 7/25.
P7: 1/46, 10/37, 3/61, 2/13, 6/32, 5/21, 9/32, 8/89, 7/30, 4/55.
P8: 2/31, 10/86, 1/46, 5/74, 4/32, 6/88, 8/19, 9/48, 7/36, 3/79.
P9: 10/76, 1/69, 3/76, 5/51, 2/85, 9/11, 6/40, 7/89, 4/26, 8/74.
P10: 1/85, 10/13, 2/61, 6/7, 8/64, 9/76, 5/47, 3/52, 4/90, 7/45.
----------------------
For understanding how to read this notation, see my previous problem.
Best Regards,
George
Member for
24 years 8 monthsGeorge,we do not make our
George,
we do not make our optimization algorithms public. It is rather complex iterative heuristics. We did not compare Spider schedules with Preactor's. This information we got from our customers in Brazil.
I tried backward scheduling but the result was not improved. It is possible to try options applying user defined priorities but it is time consuming and hard when the schedules consist of many thousands activities. We tried to make the default schedule as close to optimal as possible with very limited number of iterations. Resource scheduling shall be very fast to provide good schedules at the start of each shift and the schedules where Spider is used are usually large.
Best Regards,
Vladimir
Member for
19 years 10 monthsHi George I would love
Hi George
I would love to help but I am heavily involved in an arbitration.
You can download a 30 day trial version of Asta PowerProject v 11.04 at
www.astadev.com
Best regards
Mike T.
Member for
14 years 4 monthsVladimir,Thanks for your
Vladimir,
Thanks for your information about activity duration in project scheduling. I am still learning and learning. Raf selected Optimization Plus method on the Resource Constrained Scheduling Options form. How does the method optimize the schedule? Raf mentioned that perhaps the method searches some prioritization rules under several layers (iterative heuristics?). By the way, why Spider schedules are much shorter than Preactor schedules?
Rafael,
Can you run my problem (6x6) again and this time with Backward Direction (instead of Forward) set on the Resource Constrained Scheduling Options form? You might find a shorter schedule with 55 minutes total duration, I hope.
It would be very useful if somebody would solve Vladimir and my problems by other project management software, like Mike with Asta. So we could compare them by quality of resource allocating.
Best Regards,
George
Member for
24 years 8 monthsRafael,thank you for your
Rafael,
thank you for your help.
George,
usually initial information for such projects is not activity durations, but volumes (quantities) of work to be done on activities and productivities of assigned resources. Activity duration is calculated as the ratio of volume of work and total productivity of all assigned resources.
You can also assign skills necessary for doing the job. If resources that have necessary skill are known Spider will select resources to be assigned basing on default or user defined priorities and resource availabilities. In this case activity durations are not known before scheduling because different resources have different productivities and durations are calculated in the process of project scheduling when assignments are selected.
Best Regards,
Vladimir
Member for
21 years 8 monthsGeorge,It takes fractions of
George,
It takes fractions of a second, perhaps faster than the time it takes your sight to follow the cursor. The software is designed to work with thousands of activities per job and a few jobs opened at the same time.
Look at the following video screen capture.
http://www.youtube.com/watch?v=HRTlsExVCGo
It was done selecting the Optimization algorithm, is 100% automatic. The others not necessarily will provide you with a shorter schedule, no matter which prioritization rules you use. The bigger the schedule the more you will notice the difference between Spider and the rest.
At times it is better to use the other methods as to have some control, especially when using "Apply activity prioritieas" and "Apply phase priorities" in addition to other selected on the Priority selection box. Then when in trouble go to full optimization, here the Priority selection box will be dimmed and the software will look for full optimization without regard to a pre-defined priority, perhaps in Optimization modes it searches some prioritization rules under several layers, if this makes sense.
The following screen will show you the resource leveling options screen.
You can download the Spider File for your use with the demo so you can explore it yourself and find out if there is any error.
http://www.mediafire.com/?a1iw802b74gema2
If you do not work multiple jobs linked together or sharing resources, each job thousands of activities Vladimir might help you select the best option for your needs, it is a scalable product.
Best regards,
Rafael
Member for
14 years 4 monthsRafael,Wonderful!
Rafael,
Wonderful! Congratulations! It is a very good schedule. It looks like the gold medal will go to the Spider team. If the Asta PowerProject team, or another team, does not find a shorter schedule, gold will go to Rafael for the Spider team.
Rafael, did you produce the great schedule out of the box (without applying user defined priorities)? How long was the calculation time?
Anyway, I must thank you for your time and effort.
Cheers,
George
Member for
21 years 8 monthsI got it with 56 minutes
I got it with 56 minutes total duration.
Member for
14 years 4 monthsHi Vladimir,Thank you for
Hi Vladimir,
Thank you for your detailed response and your time with the problem (4 projects and 3 resources). Why Spider schedules are much shorter than Preactor schedules? I am trying to find software which is better than others, producing shorter schedules than competitors can produce. I do not care about optimal schedules, I only care about just better schedules than others can produce. How do iterative heuristics of Spider find a good solution in this problem of yours?
Mike, thanks for participation in this discussion. Is your schedule shorter than 51 minutes?
Vladimir, can you try another problem with 6 projects and 6 resources? No tool change time (set-up time) is included, and each resource has capacity 1 (quantity 1). To describe the problem, I will use a short notation: resource number/duration. For example, 2/1 means the operation needs resource number 2 for 1 minute.
--------
Problem (6 projects, 6 resources):
P1: 2/1, 6/3, 1/6, 3/7, 5/3, 4/6.
P2: 1/8, 2/5, 4/10, 5/10, 6/10, 3/4.
P3: 2/5, 3/4, 5/8, 6/9, 1/1, 4/7.
P4: 1/5, 6/5, 2/5, 3/3, 4/8, 5/9.
P5: 2/9, 1/3, 4/5, 5/4, 6/3, 3/1.
P6: 1/3, 3/3, 5/9, 6/10, 4/4, 2/1.
---------
Read the first line like this: Project P1: the first operation needs resource R2 for 1 minute, the second operation needs resource R6 for 3 minutes, then operation 3 needs resource R1 for 6 minutes, etc. Notice that each project uses each resource but in a different sequence. In the Vladimir problem, all 4 projects have the same sequence of resources (R1, R2, R3).
Mike, can Asta PowerProject find a shorter schedule than Spider Project?
It sounds like the Olympic Games in Project Management software.
Cheers,
George
george.mejtsky@yahoo.com
Member for
24 years 8 monthsMike,I did not mean George
Mike,
I did not mean George example but general production scheduling.
If I don't know the next work then I don't know necessary tools and what time is necessary for tools adjustment. So I cannot add changeover activity because don't know what work will be next and what time will it take. It is not actual in project management but may be critical in production scheduling. I think that we will add this feature to Spider since we have more and more customers in manufacturing.
Did you try Asta with my example?
Best Regards,
Vladimir
Member for
19 years 10 monthsHi Vladimir I did not see any
Hi Vladimir
I did not see any item about changing tools in Georges thread - just applying Resource R1 to a number of different tasks in different projects.
That is the same as allocating Crew 1 to different sections of a pipeline.
If there is to be a time required for tool change over then that could be done with a simple task set between changeover tasks or alternativel a lead time on the link if the calendars are compatible.
Best regards
Mike T.
Member for
24 years 8 monthsGeorge,Spider Project is used
George,
Spider Project is used for production scheduling in Russia, Ukraine and Brazil. Recently I received a letter from Brazil where it was written that Spider is used for production scheduling instead of Preactor because Spider schedules are much shorter.
But Spider still does not model time necessary for changing the tools when there is a need to do different type of job. This is serious restriction if these times are large.
You described famous NP-complete problem and Spider does not guarantee the optimal solution but its iterative heuristics finds the solution that will be close to optimal. I added fourth project (machine) to the example below to show what Spider will do solving your task.
Mike, I am curious if Asta will produce the same (or better) schedule for the same problem out of the box (without applying user defined priorities). Please enter the same data into Asta and show us the result.
Regards,
Vladimir
Member for
19 years 10 monthsHi George I will be
Hi George
I will be interested to hear Vladimir's response but this is a matter of routine resource allocation in Asta PowerProject.
Best regards
Mike T.
Member for
14 years 4 monthsVladimir,I respect you, and I
Vladimir,
I respect you, and I agree with your postings. In fact, I cannot find even one sentence where I would not agree with you. You proposed to suggest hard tasks so I will try my luck. I am coming from production scheduling field, and I wonder whether your Spider Project software can solve some of shop scheduling problems. I will describe such problems by project scheduling terms.
I have several projects: The first project P1 starts with activity P1A1. The activity P1A1 requires resource R1 for p1a1r1 minutes, and then the next P1 activity A2 requires resource R2 for p1a2r2 minutes. The third activity A3 of P1 requires resource R3 for p1a3r3 minutes, etc. The second project P2 starts with activity P2A1 requiring resource R1 for p2a1r1 minutes, and then the next P2 activity A2 requires resource R2 for p2a2r2 minutes, etc. The third project P3 starts with activity P3A1 requiring resource R1 for p3a1r1, etc. So each project has a sequence of activities and each activity requires a resource for a fix time. Each resource Ri can be assigned to only one activity (resource capacity is 1). This is a resource allocation problem. The question is how to allocate each resource so that to minimize the overall completion time of all projects.
I guess Spider Project software can solve this type of problems. Can you tell me if and how it can be done in Spider?
Best Regards,
George
Member for
21 years 8 monthsRE: Let’s Challenge SPIDER
Vladimir,
Yes, it is a useful visual report, but my point is that it shines in linear projects.
And while contrary to other linear diagram tools, in Spider all the PDM functionalities are also available. The PDM metrics matter as much or even more, still if a linear job, the Graph is just a representation.
Best Regards,
Rafael
Member for
24 years 8 monthsRE: Let’s Challenge SPIDER
Rafael,
for high rise buildings it is also very useful.
The metrics consists of floors (or levels like in your example) and Lnear Diagram shows what work at what floor will be done at what time.
But in any case it is just one of many reports that may be used along with the Gantt Charts.
Best Regards,
Vladimir
Member for
21 years 8 monthsRE: Let’s Challenge SPIDER
Well, it shines in linear jobs such as pipelines and roads not in building construction.
Member for
24 years 8 monthsRE: Let’s Challenge SPIDER
Rashid,
if you will download Demo version of Spider Project from http://www.spiderproject.ru/demo_e.php you will find there sample project that includes construction part (a small part of the resl project), financing, and future profits.
In this project you will find multi-resources (crews) assigned to construction activities, activity durations that are calculated basing on their volumes of work and assigned resources productivities, cost components and cost centers, cash flows that includes expenses and financing, expenses and incomes that are calculated with cost discounting, materials that are assigned per work volume units, resources that work in shifts. In this project you can try cost and material levelling.
It is small part of many unique Spider Project features but you will not be able to repeat this project using other softwares including P6.
Spider Project optimizes resource constrained schedules. Recently Rafael uploaded small and simple project but P6 produced optimal schedule (the same as the schedule produced by Spider Project) only after manual assignment of activity priorities. Impossible in large projects. And in many real projects the difference of schedule durations is huge.
I can add skill scheduling, trend analysis, etc.
If you ask about some reports I suggest to look at Linear Diagram - it is Time-Location Chart that is one of many projectt reports.
If you want to see something specific please ask.
This thread was created for challenging Spider Project - I am still waiting for hard tasks. If you need something that other PM software does not do, ask if Spider Project can do it. Two options - I can explain how Spider does it, or you will suggest Spider Project improvement.
Best Regards,
Vladimir
Member for
21 years 8 monthsRE: Let’s Challenge SPIDER
Member for
15 years 7 monthsRE: Let’s Challenge SPIDER
Vladimir,
You sound well conversant with both spider and primavera...can you attach a layout of spider that you think P5 cant produce. Thanks please do it at your convinience.
Regards
R
Member for
17 years 5 monthsRE: Let’s Challenge SPIDER
Dear Vladimir,
I personally request Russian papers or presentations if there are any. My Russian is not good enough for that kind of stuff but I can make them translated at my work easily.
Regards,
Safak VURAL
Member for
24 years 8 monthsRE: Let’s Challenge SPIDER
Hi Safak,
I am sorry that there are few Spider papers and presentations in English. Don’t forget that it is Russian software. The documentation that is created by Russian corporations is in Russian and Brazilians publish their papers in Portuguese.
Spider site contains papers and presentations mostly made at different PMI events. At these presentations I talked about the methods that we use trying to avoid mentioning Spider. Spider Project was and is used for management of many oil&gas construction projects in Russia, Ukraine, Belarus. Examples; Caspian Pipeline, Blue Stream, Nord Stream, East Siberia – Pacific Ocean, and other pipelines, development of Bovanenkovo Gas Field.
Best Regards,
Vladimir
Member for
21 years 8 monthsRE: Let’s Challenge SPIDER
Safak,
In Spider Project you can run Scripts from outside Spider so you can have access to all the power Reference Book provides. If your software can access text files then it can communicate with Spider Project, if I understood correctly what Vladimir once mentioned in one of his postings.
Perhaps it is not a good idea to have a direct link to the database fields as this can corrupt integrity of the data, Reference Books provides the link. Field relationships in CPM are not as simple as relationships within a database.
I do not have such a requirement in my jobs but Spider can provides for the most demanding requirements, on my part you are welcomed with your questions, I believe this kind of questions were missing and your postings will add value to the discussion.
If I am right maybe in a future we will be exchanging script templates to communicate with Oracle/Primavera/Microsoft/SAP/....
Best regards,
Rafael
Member for
17 years 5 monthsRE: Let’s Challenge SPIDER
Dear Mr.Liberzon and Mr.Davilla,
First of all I want to congratulate you for the battle you continue to make people hear you. I wish you to continue your way and conquer more castles in project controls territory.
I am trying to follow this thread with playing in your demo. Everything seems so perfect user friendly and solution oriented in software. Personally ASTA – Power Project seems good scheduling software also. But the ORACLE® and PRIMAVERA® are offering some other aspects as well. Also all my clients are commitetd to them. In many projects I touch or hear (from colleagues etc.) cost control - oracle rdb, estimating and quantity surveying sql rdb, HR and personnel time recording oracle and sql rdb, QA/QC sql rdb ……. List can be longer. Data collecting is becoming easier and IT works is becoming user-friendly everyday. SPIDER® has to fight with these kinds of integrated packages in the market also due to availability of direct integration for PRIMAVERA® products with that kind of databases.
Can I challenge SPIDER® team not with software with studies, papers, procedures etc. If you check all major construction companies in OIL&GAS almost all their project control documentation based on duration based CPM where majority of them referencing PRIMAVERA® directly.
Can you provide more documents about projects which used SPIDER® and Critical Chain Project Management (Like Urucu-Manaus Gas Pipeline)? It is not easy to find papers, studies etc. supporting Critical Chain. Can you reference papers? Can you create a package that the Project Controls for Critical Chain approach with all main and support processes including inputs, outputs, responsible items, customers, where you can include SPIDER® in one or more of this processes. I checked all publications SPIDER® web page but I cannot find anything which is answering the questions above. If there are academic references you can provide I will be happy also. I will try to access them from my university library in my vacation times at my hometown.
Regards,
Safak Vural
Member for
21 years 8 monthsRE: Let’s Challenge SPIDER
Vladimir,
You got it very right; my question was about scalability and transfer of resource definitions.
The great thing about it is that scaling is defined at the activity level so when scaling your fragments only scalable activities will be scaled. If you have a fragment for mat foundations, you would transfer several activities whose duration will depend on the scale but others will not be changed such as concrete curing.
Maybe you cannot say all activities will either be fully scalable or not scalable, a few will fall in between. I would dare to say over 95% will be covered and the remaining with a simple adjustment can be handled. Hey you are transferring even resource definitions.
Please don’t complicate fragments, keep is as simple as it is, cannot get any better.
Best regards,
Rafael
Member for
24 years 8 monthsRE: Let’s Challenge SPIDER
Rafael,
I dont know software packages that have similar functions.
This is the way we create complex project models.
Fragments describe typical work packages for certain work quantity (1km, 10m3, etc.). Inserting the fragment project planner defines the real volume of work at the certain work package and fragment data will be adjusted automatically.
With fragment library it is easy to create large project models:
Project Planner creates WBS, then inserts project fragments at work packages level, then creates links between activities of different work packages. Everything else is already there - resources, costs, calendars.
Fragment Library is the main element of the corporate PM system.
Best Regards,
Vladimir
Member for
21 years 8 monthsRE: Let’s Challenge SPIDER
Vladimir,
Thanks you for your briefing on the application of fragments.
…”For repeating sets of activities we suggest to use the typical fragments library that consists of small projects that model typical sets of works. You can use insert other projects as the new phases. This is the way we use working with the fragments. The software asks what to do with activity codes and volumes. Activities may be scalable or not (look at activity properties). If scalable then their volumes, durations, etc. will be multiplied by the user defined number”.
I noted that even resources definition is transferred so if new resources are required these will also be transferred.
This feature of being able to scale the fragments is something I have never seen before. With Primavera SureTrak I did not even had the basic functionalities of fragments. Do you know if such “scalable” and transfer of resource definitions are features available in other software?
Best regards,
Rafael