Civil Engineering Association

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Hi

I have query regarding the piracy of the softwares.

my question to all is

DOES THE PIRATED SOFTWARES GIVE BAD RESULTS FOR THE CALCULATIONS / SIMULATIONS? I MEAN CAN ONE BE DEPENDENT ON THE RESULTS GIVEN BY A PIRATED SOFTWARE?

To my understanding I personally feel that the fully unlocked/pirated software will perform as good as a genuine software. However, it can happen that some modules in the cracked softwares may be locked but those modules which are unlocked will be performing perfectly.

I would like sum pros to throw sum light on this topic.

thnxs & regds

subodh
I report my experieces on geotechnical sw:
when I read the update changes on the official website of sw I fill pain and I'm afraid.
One time i've read that the software (I don't remember if was phase or plaxis) multiply the property of structural elements instead divide that.
Yestarday my colleage shout about the different results between phase 2 v7 and v8 (same model) using double liner with interface (very big difference!).
Today someone told me that the result of MASW were wrong for some matter, but the results
were those.
I'm little tired: "million" of software, but one (original!!) that give a good reliability?
(basic assumption is that people don't have to use abaqus to design a silly retaining wall....)
Then the only thing that can save us is the experiences. Problem is not connected with cracked sw....
I red something interesting about geotechnical sw:
The application of finite element analysis to the design of embedded retaining walls
PhD RICHARD IAN WOODS, 2003
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It's old stuff but pdf page 23, 24, 25 (doc. pages I- 6-8) really got my attention:
Quote:Anomalies and unexpected results had cropped up in the analysis of a variety of geotechnical problems ... due to:
a) bugs within the code itself (program not working as stated)
b) user errors in the input data (program not solving the problem intended)
C) inappropriate use or misunderstanding of finite elements (program not being used as envisaged)
d) genuine though unanticipated response (program behaving correctly but not as expected)
It applies to other engineering software as well. I encourage you to read it when you have some spare time.

Software hides it's bugs by using disclaimers. Open your favorite and read.
Those typically encourage users to check the output. Easy for a simply restrained beam for which no software is required and hard for a multistory building for which a software justifies it's price. Check by comparing, but with what if the structure is uncommon, a different software and even design team, who will pay, and why pay twice?

For products too like let's say corrugated sheet:
Quote:The tables are not a substitute for the structural analyses required for the building design.
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So I'm supposed to learn two design software, make the same model in both, compare results, find why are different, find and read/buy some literature for every uncommon structure, check the products technical data, make drawings, print and after check drawings (problem with plotstyle, bad plotter, wrong version of reader), do by hand material lists and compare with software, not excel because it might have bugs Happy....

To check some corrugated metal sheet acc. to EC it takes about week the first time, if you have all the data. Maybe another week to build an excel which might be used for the same shape type.

I wander when design codes will start having disclaimers too. Many eurocodes advice to use in design experimental study.

Enough off topic

Patching:
A software developer commonly places license checks in various places in code and so in program parts. Most have a from time to time check which triggers at fixed or even variable time intervals. Some look first if the software is monitored by some hacker tool. Some checks are silent other raise a message like License not valid.
A cracker typically searches for checks which are somehow related to license validation. The depth of it's search is based on experience, talent, money, enthusiasm, a human like everyone else.
Some of the license checks trigger when you click some button, an important one like run analysis, or a not so important one like make drawings or output report.
A good (well paid and innovative) software developer will embed more than one type of check (completely different and independent) to deceive a cracker.
Protecting software takes time and money and testing and bug checking and it's a part of the sw price.

If let's say an error occurs when a license check fails, that part of the code will not run, if the error is silent or hidden the cracker might not see it, if that part of code was required to let's say change some property of material, it can be skipped. So the software can run apparently flawlessly but because of some internal error or skipped code will provide wrong results. The cracker might even accidentally jumped over some instructions.

Fake license:
A fake license, dongle, without altering the software will yield the same product you pay for. No difference between as long as cloning or replica is well done.

Most likely no software developer wishes for users to know that it's product has bugs. Including pirated versions. And it seems that pirating software is tolerated. If you draw the line it's all about money, image, advertising, brand, habit. Altering results if crack is detected will never improve his image or increase the number of clients.
Tekla has used a tag to mark drawings, also it is said that the model contains license information.
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To draw a conclusion, based on disclaimers with or without license you still have to analyze problems with more than one software and have some expert advice&review.
I'm adding this, it's one of my favorite, I show it occasionally to new users of sap or etabs:
[Image: 58626001581459801162.png]

The same very simple model is analyzed in etabs or sap. The results are different because of end length offsets and moment release assignment.
All 3 share the same geometry and load and sections, a 0.5x0.5 rectangular section with default material STEEL I've picked kN-m units, although not important.
The load is uniform q=20 in this case kN/m.

In etabs end offsets are enabled by default which is good and bad, it depends.
In sap end offsets are disabled by default and the same applies.

If one would model the same, without touching end length offsets results will be like A in etabs and like C in sap.

For A, the beam is pinned, when end releases are applied software assumes the beam span is between column interior faces L=6-0.5=5.5 and so
M=q*L^2/8=20*5.5^2/8=75.625 (etabs shows 75 because the default number of output stations is 3, an number of 11 will do the trick)

For B, the columns are pinned, at top, from the statics point of view A and B are identical, but because of end length offsets the release is under the beam, statics look way more difficult to solve by hand.

For C, end length offsets are removed, M=q*L^2/8=20*6^2/8=90, doesn't matter if you assign releases to column or beam.

Between A and C the design moment error percent is:
6^2 vs 5.5^2; 36 vs 30.25; 36/30.25=19% ; default output stations 90/75=20%
For span=20 and columns 1x1: 20^2 vs 19^2; 400 vs 361; 400/361 = 10%
For span=6 and columns of 1x1 36/25 = 44% difference

Now doing the same let's say supermarket precast concrete model with columns having fork top pinned connection to beams in sap vs etabs with default will yield different results. Because the pinned connection is centered on column and beam (a typical detail in some regions for these structures) the etabs user will underestimate the bending moment in beams in etabs with default.
The same goes for other if the model doesn't follow the construction details and the software and user makes wrong assumptions.

So license or not, in the two software made by the same company, with almost identical interface, results can be different although input is apparently identical.
see also:
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I'm in complete agreement with Brandizzo and Livium.
My first addition is that usually if the software-maker decides to incorporate wrong results (if his proggie was cracked) he makes this to be obvious for the graduated engineer. That's the aim: the cracker would not notice i.e. hydraulic losses in thousands of meters (AFT programs), or zig-zaggy diagrams (Radimpex). The engineer using the program will notice this immediately and would not say "the programmers don't know anything". LiviuM actually mentioned the same - nobody wants to be blamed for poor program that costs tenths of thousands.

The second is.. don't trust even the most expensive programs. The more money you pay doesn't make the results closer to reality. The more "secret black box" the program is - the more difficult is for the engineers to check what goes wrong there. On the opposite - free programs with open source are easy to be checked by the professionals and because they are usually much simpler programs (not so many "options" and space-age graphics to inflate the code) - it is easier for the programmer to handle it entirely.
There are well-said design project checkers. Some of them are professors, other are very good engineers with a big experience in designing no matter what they are PhD or not. They belong as a professional asociation to Ministry of Works. Anyway, what I mean is that some of checker accept results from softwares others don't trust them, especially the aged of them.

But the most important thing is that they check the design calculations with the old empirical methods which are very good and less known nowadays. If we will know how to verify us via empirical methods we can have a better control about software results, even they are cracked or not.
This is my opinnion.
Regards,
3fan
A previous student used a pirated copy of PLAXIS. My supervisor and him struggled as it was giving incorrect results, yet they knew they did everything perfectly. They later got a trial version for plaxis which worked fine.
Quote:... student used a pirated copy of PLAXIS...
Hmm.. which version? Was the trial the same version?
(12-14-2013, 07:26 AM)ynopum Wrote: [ -> ]Hmm.. which version? Was the trial the same version?

The student had an older version. My supervisor said the software had a bug. A different student bought Plaxis, and there was never any issues using it.
Yes i agreed to all of above comments. I would like to add one-more point here any kind of cracks/medicines are available in net ll not change any program algorithms (Software developer ll not write wrong program & algorithms). Those ll only modify(lock/unlock) the license related parameters. So there is no chances of getting wrong results in pirated software's. Getting wrong results is purely related to wrong modeling or wrong inputs given to software or due to bug in software program. Some inexperienced peoples created these conclusions about pirated software's.
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