Science topic

Failure - Science topic

Explore the latest questions and answers in Failure, and find Failure experts.
Questions related to Failure
  • asked a question related to Failure
Question
10 answers
Hi, I'm looking for a real fog/edge dataset/trace that contains resource and tasks events such as failure, completion, to model trust, reliability, and availability.
Relevant answer
Answer
Did you find a dataset?
  • asked a question related to Failure
Question
1 answer
While designing a model on SAP2000, post analysis when we perform the design check, there's a colour bar to the right hand side of the window with some values. I'm assuming that these may be the demand to capacity ratios because when these values are >1, the members become red (as indicated in the colour bar) and indicate a certain failure. Assuming I have dealt with all types of failure (as indicated in "Identify all failures"), which region should the members lie in? The answer can include suggestions where economical design is considered and ignored as well. I only wish to be clear with the underlying concept. I have attached an image of a frame I've designed for clarity.
Relevant answer
Answer
You are right. The values are demand/capacity ratio. In columns they are the sum of P-M2-M3 ratios and in beams are major bending ratios.
  • asked a question related to Failure
Question
1 answer
I am looking for information on the pressure tree roots (by expansion) can exert on structures as retaining walls and quay walls. Failure of retaining walls by root pressure is very common. Is there any way/model to determine this load?
Relevant answer
Answer
There are some experimental papers on force measurement by plant tree roots:
You may use an inverted analysis of paper B with rod theory to derive root pressure.
Hope it helps
  • asked a question related to Failure
Question
2 answers
Anyone, who has done a composite analysis in Abaqus?
I have calculated Tsai hill, and Tsai wu stresses but I want to calculate Failure Index IF ( as I have already input strengths in material>suboptions>fail stress, I am interested in failure). Is the stress calculated as Tsai wu, tsai hill in attached image same as Failure index? Please
Relevant answer
Answer
Can you share your Abaqus model (.inp) ?
  • asked a question related to Failure
Question
3 answers
I am working on material studio 2020, CASTEP module, when I optimize the geometry, I am getting this message at each job failure
[mpiexec@Rahat-Saqfi] ..\hydra\pm\pmiserv\pmiserv_cb.c (863): connection to proxy 0 at host Rahat-Saqfi failed
[mpiexec@Rahat-Saqfi] ..\hydra\tools\demux\demux_select.c (103): callback returned error status
[mpiexec@Rahat-Saqfi] ..\hydra\pm\pmiserv\pmiserv_pmci.c (520): error waiting for event
[mpiexec@Rahat-Saqfi] ..\hydra\ui\mpich\mpiexec.c (1149): process manager error waiting for completion
How to resolve it?
Relevant answer
Answer
I don't have much experience with Intel's MPI, unfortunately. It's probably best to contact BIOVIA Support, I'm sure they'll have seen this before. Alternatively, you could ask Intel directly, but they aren't always very good at responding.
In the mean time, you could check the hydra service is actually running, by using:
hydra_service.exe -status
And you can test the Gateway etc using the Licence Administrator tools.
If all else fails, you can get the free academic CASTEP licence and just compile and run CASTEP yourself, with the input files generated by Materials Studio.
  • asked a question related to Failure
Question
1 answer
If I want to know the best model for my survival data, which performance metrics will I use?
Relevant answer
Answer
You can use either the AIC or BIC, which all hinge on comparing the log-likelihood of the models allowing for differences in predictors
  • asked a question related to Failure
Question
2 answers
It's common sense that the insulation of stator deteriorate when water enters in induciton motor. I want to know a more detailed process of the failure evolution. What's the main outcome when water enters in induction motor? Is it inter-turn short circuit, phase to phase circuit or short circuit to ground? Or is there an order of these faults?
Are there literature about this research?
Relevant answer
Answer
you may want to check this link
Induction Motor Stator Interturn Short Circuit Fault Detection in Accordance with Line Current Sequence Components Using Artificial Neural Network (hindawi.com)
  • asked a question related to Failure
Question
26 answers
Suppose that we have a two-component series system, what is the probability of failure of two components at the same time?
*** both components' failure times are continuous random variables,
*** Is it important that they follow the same distribution or the different ones or the same distribution with different parameters?
Relevant answer
Answer
The practical significance of the need to know Pr{ X=Y } may come from the need of estimating losses caused by catastrophic coincidence of two failures of a two-part system. Usually it happens with possibility of appearance of a common cause of a simultaneous failure. In case of a thunder it is rather am artificial model replacing the due three-part system instead. But there are real systems where the common causes are hidden. In such cases statistical analysis of models with non-zero probability of the coincidence are very useful.
Simplest theoretical models of some practical value are introduced in works by [R.] Barlow and [F.] Proschan in late 60's.
Example: If X= min{T1,T2} Y=min{T2,T3} with independent exponential T's. Then
Pr{ X=Y} = lambda2/sum_ of _ lambdas
where lambdas are the inverses of the mean values of the correspondings T's.
  • asked a question related to Failure
Question
5 answers
Hello everyone,
I need to know if there is any software available to model the rainfall-induced slope failure? For instance, having the rainfall intensity and duration, can determine the infiltration of water in the soil and further calculate the slope stability condition?
Relevant answer
Answer
SR2 (RocsCience) allows you to simulate the effect of rain by defining the infiltration in m/s. As a result it gives you the water table and you can calculate the resulting safety factor by applying the SSR technique
  • asked a question related to Failure
Question
4 answers
Upon conducting submersion tests of thiol/ene polymers in PBS at 37C, the polymer shows a reduction in strain to failure in comparison with the dry test.
Relevant answer
Answer
Good day! Some general options, but not specific for your polymer-phase system, come to my mind that probably should be considered: atom motions, change of phase conditions and the action of phase on the polymer. Atom motions may generally matter just the permanent position changes (motion) or more or less constant position changes - the question should we even say it such a matter on crystallographical changes or material amorphization. The other question - is it possible for the phase to inhibit energy spreading in the material, thus, the same energies in different phases may cause different consequences on material. And last but not least - is there a chance for phase to interact with polymer chemically, decreasing intra- and intermolecular hydrogen/van der Waals/evectrostatic/whatever kind of bonds in the polymer in favor of polymer-phase interactions? Hope that it gave you some thoughts. Also, it would be nice if you will correct my thoughts and ideas, and share your expertise here in the discussion.
  • asked a question related to Failure
Question
3 answers
So I've expressed a protein small scale (10ml LB volume) and then scaled it up (500mL). I got good expression in the soluble in the small-scale growth. I then scaled up but it did not express soluble as I had hoped. Currently, writing up my thesis and struggling to find examples of this happening?
I repeated the scale-up several times just to confirm it wasn't an issue with a bad cell stock etc. Just looking for a citation or a few but drawing a blank, I can't be the only person who followed the advice to try small then scale up and had it not follow expectations?
Relevant answer
Answer
which culture media did you used? LB? and which induction temperature? 37°C
if you are using LB or similars inn my oprinion 1 liter in a 2.5liter shaking flask is to much to guarantee good oxigenation. I think that maximun 400ml is preferable
In case that you are not able to improve the results reducing the volumes for flask and adding the antifoam you can try to replace the media with the Enpresso media /(http://enpresso.de/en/)( the commercial high cell densiry media subject of the video on my blog, which allow you to scale down culture volume but not productivity. Is certanilly more expensive than LB but very powerfull.
good luck
Manuele
  • asked a question related to Failure
Question
1 answer
Dear all,
Concrete model in Plaxis could be utilized to capture the non-linearity of concrete. Is there anyway we could identify or estimate what is the crack width from the output? There are output state parameters such as UtilFT, Hr and so on. If not possible, based on where the tension points/failure points/strain, will it be possible to estimate or back-calculate the crack width?
Cheers guys
Relevant answer
Answer
Cracking is a defect, plaxis is a continuum based software one cannot model defects or damage in plaxis, you can use minor stresses to track where cracking is likely to occur.
  • asked a question related to Failure
Question
8 answers
To whom it may concern...
Case shown in pictures below need to stop in front of it...
What the mean of overload... What will be the meaning of calculated loading before design... and.... What really mean the structural design based on submitted data..
All, in general,.. knows that.. design start with converting functional use of the building to loading on structural element... then start design element by element ...
So, what might be the supposed loading to one story house... based on all adopted code... ? this is the first question..
Then what you think, .. or what the supervisor engineer might think the value of such loading on that slab shown in pictures attached... ? this is the second question...
Then at last... whom responsibility is that... if failure occur...? where that will be the most important question....
Limited education with low experiences causes such cases, ... or... we need to ask the supervised engineer if he care...
Relevant answer
Answer
Invariably the loading on one storey building roof with access is only `1.5 to 2 kN/m2 . and this is uni-formally distributed load. But if you pile up load in a small area more than the failure load of slab with concentrated load then the failure is imminent. this failure load can be calculated using yield line theory or by Hillerborg Strip method.
If you have this kind of loading then keep your props intact before you finish roof top work
  • asked a question related to Failure
Question
2 answers
Rubber and rubber-like elastomers fail in a brittle manner. Therefore, I have some idea how the defect free bulk material fails. I have seen such failures in tension. But I have never seen any compressive failures. Has anyone found a photo of cracking of rubber-like materials in uniaxial or planar compression? Or can anyone make such photos?
Relevant answer
Answer
Dear Manfred Staat, if I understood well the question, some element designed for anti-sismic/anti-earthquake on bridges and height buildings are pads which absorb compression load waves by cracking progressively. In cars also damping is insured by similar items. Please have a look at the following documents. My Regards
  • asked a question related to Failure
Question
1 answer
I'm dealing with indirect ELISA, In most cases while doing PLA analysis with 4 parameters logistic fit curve Parallelism & Linearity failures are observed.
Relevant answer
Answer
if you plan to do PLA analysis with 4 parameters fit curve, the data you got from the ELISA should be a full dose response curve (S curve). If the data looks not like the S curve, the parallelism test might be failed.
  • asked a question related to Failure
Question
3 answers
I m looking for a website/reports/papers which deals with already tested properties i.e. elastic moduli, poison ratios, tensile,compressive and shear strengths etc of different combination of compsoites for use in FEA in abaqus/ansys failure criterias i.e. Hashin, Tsai wu etc.
Relevant answer
Answer
Hi Sadiq Amin,
According to the material and analysis you want to simulate in the ABAQUS, you need to search in ScienceDirect, Springer, or other publishers’ websites. Find if there are any articles related to your material and analysis.
Best regards.
  • asked a question related to Failure
Question
3 answers
I have to simulate a pipeline which is API 5L X60. I've been searching in the literature and I didn't find anything.
Relevant answer
Answer
I still looking for the answer T_T
  • asked a question related to Failure
Question
2 answers
Please provide formulas to find parameter fracture strain, Displacement at failure, Stress triaxiality, Strain rate..
Thanks in advance
  • asked a question related to Failure
Question
10 answers
The individual foundations of the structures have been completely removed
The walls must be connected with foot girders which, mainly, try to receive the overturning torque.
That is, we do not rely on individual foundations to receive torque.
Much more ... when there are multi-storey constructions, there are always the corresponding floors of the Underground, which "anchor" the reinforcement of the wall.
It has been proven that buildings with Underground floors are much stronger in the earthquake because there is better anchoring of the superstructure reinforcement inside the basement walls, and because the walls of the Underground floors are strong in torques.
Foot girders in large earthquakes, try unsuccessfully to pick up these huge torques that lower the walls of smaller buildings, and are usually unable to pick them up.
But as much as it seems that the anchoring of the wall reinforcement inside the Underground floors is the same with my own design proposal, they are different.
I do not suggest just a simple anchoring to the ground.
I suggest compression on the sides of the walls combined with anchoring in the ground.
Where are the differences between the anchoring inside the walls of the Underground floors, and the pre-tensioning + anchoring to the ground.
1) We insulate the Underground floors externally, then we rub them around the perimeter.
Due to the looseness of the rubble, their reaction to the torque of the whole structure is small.
But they resist with their own weight and this is a positive reaction to the moments.
If the Underground floors have the same mass as the mass of the upper structure, then yes we have anchoring.
But this is not possible.
Usually the floors are much more than the Underground floors and this means that the Underground floors in large earthquakes have a tendency to overturn, but small.
Beware .. I'm not talking about a complete overturning of the building, but a small overturn of the total area of ​​the base of the Underground floors.
This means that the building loses some ground support.
This is equivalent to creating a corresponding torque from the unsupported static loads, which contrasts with the torque of the building.
These two opposing torques create cross-sectional failures.
This does not happen with the full anchor with my mechanism
2) The prestressing that I propose on the sides of the walls ensures less deformation by bending, zeroes the tensile strength in the cross section, at which point the shear failure of the coating concrete due to the high tensile strength of the steel and its low tensile strength. It ensures that after leaks the construction will return to its original position, so the pre-tension is considered elastic functionality.
It also provides resistance to the shear of the base. Anchoring + prestressing ensures the neutralization of moments (M), upright forces (N) (compressive and tensile), and shear (Q) and deflects inertia tensions into the ground by preventing displacements that deform and break cross-sections around them. nodes.
Relevant answer
Answer
Interesting question...... but it is away from my field; follow for more informative responses
  • asked a question related to Failure
Question
5 answers
What failure criteria can be more efficient for the analysis of cracked rock mass under linear elastic conditions?
Relevant answer
Answer
In my opinion, the Griffith failure criterion can be a good option, considering that it has been discussed in many sources ( e.g., Fracture Mechanics, (2011) by Chin-Teh Sun, Zhihe Jin ) it can be a suitable and complete criterion in rock masses.
  • asked a question related to Failure
Question
2 answers
Knee injuries in paediatric population are increasing signifi-
cantly these past few years and become more common because
of rising sports participation and competitive sports. Anterior cru-
ciate ligament (ACL) injuries may represent 30% of all knee injuries
in young soccer players. The number of ACL ruptures in young
population increases also secondary to much more accurate diag-
nosis methods such as early magnetic resonance imaging (MRI).
Because knee injuries in children could easily evolve towards early
arthritis, it should not be mistreated.the treatment of ACL ruptures in skeletally immature patients is not consensual. Several studies reported failure of conserva-
tive management and a more stable and functional knee after
ACL reconstruction in active child.
Relevant answer
Answer
@Ganesh S Dharmshaktu sir thank you for your inputs, before the advancement of MR imaging and arthroscopy; the internal derangement of knee in children was generally managed conservatively with rest and immobilization. This has greater advantage for nondisplaced/minimally displaced avulsions of tibial eminence. The risk vs benefit of conservative
approach for ACL injury in children needs to more in attention.
  • asked a question related to Failure
Question
4 answers
Multisim summary (Mon Jun 14 14:01:32 2021):
Stage 1 completed.
Stage 2 failed.
Stage 3 not run.
Total duration: 0h 1' 20"
Multisim failed.
Relevant answer
Answer
Were you able to figure out a solution to this problem?
  • asked a question related to Failure
Question
4 answers
Hello, my question is about the analysis of miniature currents. For weeks I tried to buy the program without success due to a failure of your SSL server. So far I have analyzed my records with the ClampFit threshold search option, taking into account that the parameters are not so specific and that they could alter the results obtained.
Relevant answer
Answer
There is a software called 'minis' (https://github.com/dervinism/minis) that does the job better.
It's been described as part of the benchmarking analysis comparing 'minis', Mini Analysis, and Clampfit. The link is below
Martynas Dervinis, Guy Major
bioRxiv 2022.03.20.485046; doi: https://doi.org/10.1101/2022.03.20.485046
  • asked a question related to Failure
Question
9 answers
So the question remains: Why are we just now calling out learning gaps for our children when they’ve been experiencing significant literacy failure for nearly 30 years?
Relevant answer
Answer
The first IQ test was developed in the early 1900's because the French Ministry of Education recognized that some children were not as prepared as others for learning basic reading and math skills (they realized there was a gap between some students entering public education and others). Many people mistakenly believe that the IQ test measures overall intelligence, when in fact it measures one's preparedness for being able to process academic tasks, which is why it correlates strongly with educational attainment. It is also probably the assessment that has been most thoroughly analyzed statistically, historically.
But it is predictive rather than an assessment of prior achievement. It also does no specifically measure literacy. My point in mentioning the IQ test was that gaps in education have been recognized for more than a century.
In terms of literacy, specifically, I don't think there has been more literacy failure over the last 30 years than at other times in the nation's history. During the end of the 20th century there was a decades-long controversy regarding whether a phonics or whole-language approach would be the more effective intervention. I think the current view is that both are essential, though each is most beneficial at different points in a child's development. My conclusion, based on the most current information, is that the gaps we see after the 4th grade slump are largely the result of differences in background knowledge and that reading interventions over the past 30 years have not been designed for nor done a good job of addressing that aspect.
Daniel Willingham, a cognitive scientist from the University of Virginia, has written some useful papers on the subject. I've attached some resources that I have my undergraduates read in some of the reading courses I teach that may be helpful.
  • asked a question related to Failure
Question
4 answers
The ethical behavior of management determines the success or failure of the business in the long run. Anyone with unethical behavior may seem to get progress in short intervals but in the long run, such behavior may lead to nowhere, mostly destined to the failure. We can have observations with such sort actions of some companies on this ground. The history shows that all those firms with their unethical affairs turned to have the poor fate, failure.
Relevant answer
Answer
Mostly subjective and self-guidance of managers. Some laws are there but managers need to be ethical and morally bound. some tussle between management and CEO like Ashneer Grover (Shart Tank) Vs his company Bharat Pay highlishts some issues to this area.
  • asked a question related to Failure
Question
1 answer
Hello readers,
I am modelling failure in MJC model using the Cock-Croft and Latham fracture model. I have the values of failure strain and energy. I am having a little confusion as to in what card should I input the failure strain for Cock-Croft and Latham fracture model.
Can you please help?
Thanks & regards,
  • asked a question related to Failure
Question
1 answer
I'm inducing M0 macrophages from THP-1 by using Phorbol 12-myristate 13-acetate (PMA)
But frome time to time, I encounter induction failure (twice now), which could be fixed by new PMA stock.
I would like to have some suggestions on storing PMA?
Currently I preserve 5000x and 1000x stock,
5000x stock dissolved in DMSO, and 1000x was diluted from 5000x with PBS.
All stock was store in -20°C.
Is there any suggestions about how many freeze-defreeze cycle PMA could encounter, or if PMA can't left on ice for too long?
Thanks!
Relevant answer
Answer
Here are some suggestions.
You make a stock of 5000x in DMSO and then make aliquots of this stock and store in -20 degree C under dark conditions. This stock will last for least 6 months. Make aliquots of this stock in such a way that it could be used only for single use so that repeated freeze-thaw cycles could be avoided.
Do not preserve 1000x diluted stock made in PBS. You will have to make fresh diluted stock in aqueous medium each time you perform your experiment. Such diluted stocks are not stable when prepared and stored.
The diluted stock and the working solution of PMA should be prepared and used on the day of the experiment and could be reused on the same day if you are planning for another experiment on that day. Do not store the diluted stock and working solutions of PMA.
Best Wishes.
  • asked a question related to Failure
Question
5 answers
I am trying to define plastic hinge in SAP2000 but nothing shows the failure of element after reaching its capacity
Relevant answer
Answer
you have to choose proper case/combo in "Auto Hinge Assignment" dialog box in SAP2000. There is also a couple of radio buttons which have to be chosen correctly.
best regards
  • asked a question related to Failure
Question
3 answers
I would like to know if there is an established theory to determine the fatigue behavior of materials if the loading is stopped due to time limitations before the sample fails. Due to the application of loading (tension-compression or bending or cyclic loading), some damage will occur in the material internally. Are there any well-known procedures to determine the damage variable when the loading is halted before the failure of the material occurs? How can we determine the damage variable when the material experiences plastic shakedown (no ratcheting)?
Could you kindly share with me your idea, well-known publication lists, and so on? Thanks a lot for your precious time and kind attention.
Relevant answer
Answer
"For extrapolation of obtained data and limit prediction, theory of fatique may be used , for example, the parametric Sherby-Dorn equation"
On the above many papers are there you can find solution for your problem
  • asked a question related to Failure
Question
1 answer
"DP(0) A solver failure occured during the run in the Fluid Flow(Fluent) system."
Does anyone know about the solution to this problem? I have been sitting 3 months trying to solve this.What could be the possible causes?
It's a Transient Fluent+Transient Structural Simulation.
Note:I have run and got expected results with running just the fluent part(main part).
Thanks in advance.
Relevant answer
Answer
Ahmed Abrar If it is a two-way FSI, the possible reason is fluid mesh is deforming more due to large deformations from the solid side. One standard answer is to reduce the time step size in fluent and improve the mesh quality. Also, have a relook at the re-meshing/dynamic mesh settings in fluent.
  • asked a question related to Failure
Question
1 answer
I recently learnt how to use Plaxis for my thesis, however I do not know how to interpret the result correctly.
The displacement profile is showing that the maximum displacement is 47.54 x 10^6 m, and the red colour failure region is circular shape. I would like to know does it mean the failure plane is circular and total soil displaced is 47.54 x 10^6 m?
While the displacement mesh diagram, what does it mean by "displacement scaled up to 200.00 x 10^9 times"?
I would greatly appreciate it if someone could explain to me.
Relevant answer
Answer
Dear Ong,
Regardless the software used, looking at the pictures, I suspect there is something wrong with the model (e.g. boundary conditions, material properties, etc.). Perhaps, it is worth checking the units of your input parameters as well as their magnitude.
I do not know the order of magnitude of the loads applied onto the structure, but I would expect the max displacement to not exceed 0.X meters.
The deformed shape of the structure has been scaled down by 200x10^-9 times as, indeed, the displacement/deflection is way too large to be displayed in a larger scale.
I hope this helps
Vincenzo
  • asked a question related to Failure
Question
10 answers
I am trying to express a viral protease in E.coli BL21-DE3 cell induced by IPTG. As far as I know, the protein is relatively stable, non-toxic and not aggregation prone. I can not see any band confirming the presence of my protein in SDS-PAGE gel. The bands that I can see are present in both induced and non-induced samples. I have tried every possible induction temperature ( 18 degree, 25 degree and 37 degree Celsius) and IPTG concentrations (from 0.2 mM to 2mM). The result is still the same. Also the bacterial proteins are coming as very faint bands in the gel, even in the non- induced ones. The bacterial OD during the induction was 0.7 and the induction period were of 4 hours ,6 hours, 14 hours and 16 hours. I have changed my expression vectors two times. Both times the transformation had been successful but ultimately is showing same results. So can anyone please tell me what went wrong with my experiment ?
Relevant answer
Answer
Hey Banadipa Nanda,
the informations Manuele Martinelli requested are important for any further suggestions. But i would like to add some more:
1) i am not sure if i understand correctly, but have you analysed the soluble and the unsoluble fraction via SDS-PAGE?
2) You say, the bands are faint. Have you checked the concentration of your raw extract?
3) have you thought about trying another expression strain? e.g Rosetta (rare codons), Origami (disulfide formation), C41 (toxic proteins)?
regards,
Dominik
  • asked a question related to Failure
Question
1 answer
Hi! When I read the paper Progressive damage modeling in fiber-reinforced materials by I Lapczyk, JA Hurtado, I am wondering why Hashin failure is evaluated in the effective space instead of true stress space. What is the consideration here? Besides, I found that many other papers focusing on meso-scale modelling of composite laminate are ambiguous on their choice between these two stress spaces? Any thought? Thx!
Relevant answer
Answer
The effective stress σ^ on the damaged area A^ is in equilibrium with the "true" stress σ on the undamaged area A, i.e. σ^A^=σA. The damaged area A^ is smaller than the undamaged area A by the damage. From A^<A it follows σ^>σ. The Hashin model as well as other damage models can be expressed with the damage operator M by σ^=.
  • asked a question related to Failure
Question
4 answers
hi, good day to everyone.
how can we justifly the intensity of the damage in the bridge. there are certain scales that developed by different researchers to classify the level of the damage. some damages are minor moderate and severe. but i need to know how can we justify weather its minor or major damage. does this require any expert who can inspect the damage? or there are other ways we can predict the level of the damage?
thanks
Relevant answer
Answer
If the purpose of damage classification is to assess rehabilitation requirement, then as Samy Elhadi Oussadou mentions, site inspection of the Bridge is a must. On site measurements needs to be tabulated, also samples at strategic locations must be collected in order to assess the stage of deterioration of the bridge materials. Severity of damage usually corresponds to extreme corrosion and deterioration as well as major loss of material.
Since the damage itself has multitude of causes, it is therefore difficult to accurately predict the level of damage. However, main benchmarking may be used to assess the damage pertaining to a particular type by identifying and classifying the values for particular common damage causes such as carbonation, sulphate attack, chloride ion penetration, environmental and physical attack such as freeze thaw etc, and rather than trying to predict the condition of the structure as a whole, condition correlating to individual identifiers may be used to prescribe rehabilitation methods to increase the service life of the structure.
  • asked a question related to Failure
Question
3 answers
I am having an issue with my bird strike simulation. I am trying to simulate a bird strike with an Elastic-Plastic Solids with Damage and Failure constitutive bird model. I select element deletion option as 'Yes' under Element Type options. Elements are starting to break after a time but they are not vanishing from the model, as in figure. Can you tell me why I am having this issue. Sincerely, Kenan.
Relevant answer
Answer
Hi, it might be "standard" behaviour of Abaqus, the fastest way to get rid of the overly displaced elements for visualization purposes is to create a display group, in which the failed elements are not shown:
Create Display Group -> Elements -> Result Value -> Field Output -> DUCTCRT (or whatever damage criterion you might have) -> Min: 0.99 (or some other threshold), Max: 1 -> Remove.
My guess is, that the stiffness is degraded but the elements themselves are not deleted in during the simulation, which would alter the system size. Therefore, they undergo massive distortion.
BTW: I know your figure is not very representative for the quality of the simulation due to the "exploded" elements, but it looks a lot like hourglassing is also an issue, so better use fully integrated linear elements.
Sincerely,
Olaf
  • asked a question related to Failure
Question
7 answers
ML and Mechanics are completely two different fields. However, both of them works for same physical problems, failure mechanism or test results. Finite element can solve most of the structural issues through complex stiffness matrix. ML deals data of complex issues with more number of variables. The relation between ML and Mechanics are yet to be developed.
Relevant answer
Answer
Khondaker Sakil Ahmed , I think a majority of the work point towards AI/ML playing a complementary role rather than replicating the physics/mechanics of the problem. For this, A book that I have also found useful along the "replicating the physics/mechanics" dimension is "Physics-based Deep Learning Book": https://physicsbaseddeeplearning.org/intro.html
  • asked a question related to Failure
Question
4 answers
I had tried to run the input file with UDMGINI subroutine given in Abaqus documentation using Cae and command line.
I got following error in DAT file:
1. A Material property has defined more than once for this material
1. There is no material by the name " Material 1"
It will be very helpful for me if someone explain the procedure to run the UDMGINI subroutine.
Line edited in keyword is :
** MATERIALS
**
*Material, name=Material 1
*Damage Initiation, criterion=USER, Failure mechanisms=2, PROPERTIES=4
0.001,0.0001,0.0001,0.0001
*Damage Evolution, type=ENERGY, softening=EXPONENTIAL
0.1,
*Damage Stabilization
0.001
*Elastic
10000., 0.4
Relevant answer
Answer
Hv you done with your work as I am interested to use this subroutine
  • asked a question related to Failure
Question
155 answers
For example, how to analyze the effect of speed on a binary performance (success or failure), knowing that the expected probabilities do not necessarily form a straight line but could be an inverted u-shaped curve.
To understand better I created a dataset on R and I put the script at your disposal. I have also attached a graph that shows the frequency of success as a function of speed.
Thank you.
Relevant answer
Answer
Thanks Dr
  • asked a question related to Failure
Question
2 answers
Hello I seek the expert's opinion on breakdown voltage.
I made an oxidation layer on the metal surface and applied high voltage on it.
Oxide layer is supposed to be insulating layer but the small electron would flow due to super high voltage applied because it reaches breakdown voltage.
1. Breakdown voltage always accompanies the failure of the oxide layer?
2. What could determine the breakdown voltage of the oxide layer?
(assuming that thickness of oxide layer is same)
Relevant answer
Answer
you can read this old classic paper available on the net on breakdown mechanisms, and there are many other nice papers in the reported literature
  • asked a question related to Failure
Question
2 answers
I am doing a single point calculation in Gaussian09 with casscf method. The input command is casscf (10,9)/ 6-31g*. The output shows an error like this
Convergence failure -- run terminated.
Error termination via Lnk1e in /home/app/gaussian/g09/l510.exe
Relevant answer
Answer
Hi,
you can use SCF(maxcyc=number) in the command line to solve this error
  • asked a question related to Failure
Question
2 answers
I have three joint sets in an area with a mechanically excavated road cut the orientation of the joint sets are 86/301, 84/358, 7/303 and the orientation of the slope is 88/315. (Dip amount / Dip direction)
Relevant answer
Answer
Angle A in CSMR is the angle between plunge direction of line of intersection formed by discontinuities and slope dip direction. In your case you seem to have a very steep wedge formed by the first 2 sets. If you don't have software for kinematic analysis using stereographic projections then you can do this by hand. Use a Schmidt projection to draw the 2 joint planes and the slope face and find the intersection of the joints. Then draw 2 lines from the centre of the projection. One along the dip direction of the slope and one to the intersection point. Then measure the angle between the two lines.
  • asked a question related to Failure
Question
5 answers
Dear all,
I am looking for a research work that implemented an uncertainty or statistical framework to study the impact of the geometric parameters on the fracture response.
I appreciate any help.
Thank you in advance,
Moj Ab
  • asked a question related to Failure
Question
8 answers
Hi there! I am looking for things like the monthly denazification reports that were produced throughout the post war years in order to assess the success/failure of the denazification program. Any direction would be fantastic
Relevant answer
Answer
موضوع مهم جدا وجديد للغايه ..نزاع النازيه ...اتمنى لكم التوفيق واتمنى اتابع ما تحصلون عليه من معلومات حول هذا الموضوع
  • asked a question related to Failure
Question
4 answers
Recently, I need to culture the cell lines of MCF-7 and MCF-10A to transinfect the reconstitude plasmid DNA,but I have never culture these kinds of cell lines. I urgently need to know the relevant background knowledge to avoid the failure of experimental results. Terribly, I can't search the relevent protocols and papers.so I hope I can find the answers from the website.thanks!
Relevant answer
Answer
Hi,
One of the best ways to do this is to search for cell line names on the ATCC website (https://www.atcc.org), which provides you complete information. For example, you can get information about the organism, cell type, tissue, disease, applications, and so on. Also other important information such as growth properties, cell culture and subculturing procedure, type of media, doubling time, and other required information. For your two specific cell lines, see the links below, especially the Characteristics and Handling information sections.
  • asked a question related to Failure
Question
3 answers
hello, i am modelling a RC slab in Abaqus, the slab is supposed to fail in punching shear which is a sudden failure. i defined the nonlinear behaviour of concrete using concrete damage plasticity model, but i can't reach the desired results as the failure is not sudden (load-deflection curve shows that the load is decreasing gradually after reaching its max value, an it's supposed to be a rapid degradation not a gradual one). as well as, i know that whenever i there is a localization of cracks somewhere in the model (which is the case in my model), using concrete damage placticity model may make the results mesh-dependant. so what should i do? should i use GFI? or do i need to use concrete smeared crack model to simulate the nonlinear behaviour of concrete instead of using concrete damage placticity model?
thank you in advance.
Relevant answer
Answer
That is a good question.
  • asked a question related to Failure
Question
5 answers
these days the are so many algorithms to predict future events such as failure of machines or electrical components degradation.
which method is your favorite and why?
can you also provide a source code if there are any available online?
Relevant answer
Answer
Dear Sajad Saraygord Afshari,
Several Machine/Deep Learning algorithms are available in the literature. The selection of the best ML algorithm for a particular problem depends on many factors such as the availability of data for training, types of system/environment, availability of hardware for processing, etc. However, for prediction and decision-making problems Reinforcement learning algorithms are best (according to my observations).
For more detail, you can check
You can check the links for source code in Matlab
In Matlab Simulink Deep reinforcement learning toolbox is inbuilt. You can check the following link
  • asked a question related to Failure
Question
7 answers
Mass (kg) X acceleration = Inertia which is the same as the intersection of the base. The product of inertia if we multiply it by the height we find the overturning moment of the column. If we have a wall that has a double lever arm (except for the lever arm of height and that of width) then the product of the tipping moment is divided by the width of the wall and this will be the tipping moment of the wall. If the wall is anchored at its base, a reaction will be created to the overturning torque of the lever, which multiplies (as we have seen) the overturning forces, since, as the height increases, its overturning force also multiplies. If the anchor is at the bottom of the wall, the critical failure area will also appear there and the anchor point is also the lever of the wall. Question If the anchoring of the wall is not at its lower ends, but is at its upper ends. That is, if we place this wall on a machine - press and apply pressure to it, it will remain a lever arm or its mechanical condition will change; 1) Will we have a multiplication of the tipping forces as it happens when the anchor is applied to its lower extremities? 2) Will a critical area of ​​failure of right forces N (compression and tension) be created as it happens when the anchorage is applied to its lower extremities? In short, we know that the walls drop high torques at the base since that is where the reaction of any substandard anchorage is. If the anchoring is done on the roof (ie if pre-tensioning is applied between the upper ends of the sides of the wall and the foundation ground) it will lower torques at the base and will create or not a critical failure area;
Relevant answer
Answer
  • asked a question related to Failure
Question
5 answers
Recently we found in a mineral processing mine that column was damaged due to corrosion to a significant level. In this it seems base plate was also corroded. This requires almost entire replacement. Do we have any alternate way of repairing the same.
In some case the lower portion of columns was encased in concrete to prevent this type of failure, whether making lower portion as a composite column is advisable as this will change the entire behaviour.
Relevant answer
Answer
The interesting part in this is that this is bidirectional corner column supporting two platforms above. Inspite of so much damages in foundation the structure is still working and suggest the very high factor of safeties in mining structures.
  • asked a question related to Failure
Question
1 answer
Has anyone modeled aortic valve calcium plaque crack/failure/fracture? What crack model works the best? Can you also guide me to a good resource where I can find reliable fracture parameters? TIA
Note: I am looking into the 'concrete smeared cracking model', 'concrete damaged plasticity model', and also ductile fracture models. The issue is I have not found any reliable source clearly stating the material property/ a range of property (since calcium deposit material property can vary based on age and some other hemodynamic factors). So I am unable to test out those models.
  • asked a question related to Failure
Question
6 answers
I am obtaining very high resistance in a solar(pv) system.
Instead of getting around 1 M ohm, i have it around 20 M ohm.
The plant is around 500 kw and recently had been cleared of a lot of moss on the rooftop(but nothing was on solar modules). I want to know what are the probable reasons for the errors in insulation.
Relevant answer
Answer
Dear colleague you also could benefit from this practical research about your topic " What happens when… insulation fails?" in PV Magazine at:
  • asked a question related to Failure
Question
5 answers
I am obtaining very high resistance in a solar(pv) system.
Instead of getting around 1 M ohm, i have it around 20 M ohm.
The plant is around 500 kw and recently had been cleared of a lot of moss on the rooftop(but nothing was on solar modules). I want to know what are the probable reasons for the errors in insulation.
Relevant answer
Answer
If the degradation occurs inside the solar panels, the main cause is the potential induced degradation in the insulation layers between the solar cells and the terminals of the module. For this type of degradation please refer to the the link:https://www.lgenergy.com.au/faq/commercial-solar/what-is-pid-potential-induced-degradation
AS for the the other type of failure mechanism the insulators subjected to environments can be covered by dust and moisture. This causes leakage across the surfaces of the insulators that may cause the failure of the transmission system.
One have to keep such surfaces of the insulators clean of dust and other contaminations. It may also due to improper sizing of the insulators.
Best wishes
  • asked a question related to Failure
Question
4 answers
Also i want to know how to simulate the failure pattern(how will they break) for both material.
Relevant answer
Answer
Dear Anuj:
With regards to your question, the damage in the concrete can be simulated using the concrete-damaged plasticity model available in the ABAQUS and the Hashin's damage criteria can be used for simulating non linear behavior of the FRPs. Failure of the concrete or cfrp or reinforcements usually depends upon various parameters including: loading type, boundary conditions, strength of the materials, geometry, and slenderness limit. To know the failure criteria, you should first study the mechanism of above mentioned models.
Best regards,
S M Anas
  • asked a question related to Failure
Question
7 answers
Hello everyone,
I am trying to model a DCB (mode-1) test for a carbon-fiber composite sample on Ansys. However, I am very new to modelling and finite element analysis and I am a bit struggling.
As far as I know, it is possible to see the failure types based on some failure criteria. So, is it possible to get the time of the failure (fiber breaking, matrix cracking etc.) ? For example, could we know when the first fiber breakage occurs ?
Any help would be appreciated. Thank you very much.
Relevant answer
Answer
Dear sir
Please read, may be useful to you
  1. https://forum.ansys.com/discussion/1373/i-want-to-see-the-failure
in this various stresses are given with respect to time, we should assume that the failure occur at maximum stress, so the time required to reach the max stress, is the time of failure
  1. https://estudomec.info/files/ME_Learning-ANSYS.pdf
  2. 194_Sample-Chapter.pdf
  • asked a question related to Failure
Question
8 answers
Greetings! Looking for an advice on possible technical literature about specific subject: Influence of an acoustic waves on electronics and it's failure mechanics. If anyone is familiar with respectable source of information, please let me know. Thanks in advance!
Relevant answer
Answer
Thomas Cuff , of course I am at liberty. But this is more general, than you think. For example, ballistic calculator in rifles upon shooting.
  • asked a question related to Failure
Question
14 answers
Bearings are one of the critical components in rotary machines such as motors, wind turbines, helicopters, automobiles, and gearboxes. Most of these machine failures are caused by bearing faults. Thus, being able to detect bearing faults and predict remaining useful life (RUL) can help to provide advance failure warnings, plan the maintenance schedule, and avoid catastrophic failures. What are the most common technologies for bearing fault detection and RUL prediction?
Relevant answer
Answer
Eliseo Galli The bearings in big plants.
  • asked a question related to Failure
Question
5 answers
Bearings are one of the critical components in rotary machines such as motors, wind turbines, helicopters, automobiles, and gearboxes. Most of these machine failures are caused by bearing faults. Thus, being able to detect bearing faults and predict remaining useful life (RUL) can help to provide advance failure warnings, plan the maintenance schedule, and avoid catastrophic failures. Based on this, what are the most prevalent methods for bearing degradation detection and remaining useful life prediction?
Relevant answer
Answer
I THINK THE BELOW ATTACHMENT HELP YOU
  • asked a question related to Failure
Question
4 answers
I need to use a module to stabilize the three phase voltage on three phase three wire (delta) distribution line of an isolated micro grid system. To overcome any voltage sag or swell on the three phase three wire lines. Which is the best solution to be used ? I want device with low chance of failure for long time. Options like DVR or UPQC have lot of components so chance of failure becomes high requiring maintenance. I need to use it at a remote location where access is difficult from maintenance angle. So, what is opinion about using thyristor based regulator for each line? The power is around 15kW to be handled. Better options or any thoughts on the topic would be appreciated.
Relevant answer
Answer
Voltage regulation could be controlled by not allowing neutral point to shift by monitoring the load balance, as poor regulation would be of heavily loaded phase…
  • asked a question related to Failure
Question
3 answers
Hello advisors. I am glad to be here in this Community. If you allow me, I would ask if anyone of the members here know about Databases of cutting tools. Nowadays, I am working on a project and the main goal is to research about lifetime of cutting tools using the Cox proportional hazards model. At the moment, I just have one Database that contains cutting speed, feed rate, tool failure time and depth of cut. My research question is: Which of these variables are the most representative that give us the time of failure? Any kind of help, comments and questions are welcome.
Relevant answer
Answer
The attached paper solves a problem similar to yours. I would suggest that you get a copy of Jared Lander, R for everyone available from the z-library. If you need programs,
or have questions, please contact me. Best wishes, David Booth
  • asked a question related to Failure
Question
5 answers
The success (osseointegration) for the dental implant can be checked by opening flap after 2-6 months, but some times the implnat may be failed to do bone ingrowth into a metal implant; if we can check the success (or failure) earlier than 2 month with out surgical exposure, this will be much better to the patient than waiting months and then we tell him sorry the implant was failed.
For your opnion, please?
Relevant answer
Answer
Use the Implant stability quotient (ISQ) with the Osstell
  • asked a question related to Failure
Question
1 answer
HelIo everyone
I want to analyze a slope failure by Anura3D, but to use GID software, I need to get a password.
Can anyone help me to get it free?
or any suggestions for me to use another software without GID to simulate my problem.
Thank you
RAOUF ARIF
Relevant answer
Answer
Hi Arif Raouf ! You can request up to 3 months for free in this link.
If you need more than 3 months, you can contact gid@cimne.upc.edu
Javi Gárate
  • asked a question related to Failure
Question
6 answers
I am modeling a 3D voided slab on Diana FEA and I have a problem in defining load steps as I didn't find clear explanation for how can we set them. Can anyone please explain how are these load steps in Diana are defined? the expected failure load is 350 kN
Relevant answer
Answer
if the applied load is 350
the steps means the multiple factor 0.1(10) = 1
and the load will be as applied
  • asked a question related to Failure
Question
3 answers
I am doing bachelors in social sciences. I have already asked this before but need more opinions on this.
and If not so pls suggest few topics related to middle-eastern countries.
Relevant answer
Answer
Please go-ahead to gain your time.
  • asked a question related to Failure
Question
3 answers
I am trying to use VUMAT to damage a layer of composite. I have tried Hashin/Puck mixed criteria to simulate failure of unidirectional fiber reinforced composite. i found a code online that I have attached. I had to do some modifications but I am not sure how to pass the Variable that defines failure. I have defined the properties in "User Materials" and in "Devpar" I have pointed out the number of state variables I need along with the variable number that indicates element failure. I am for some reason still getting distorted elements error as the elements that are supposed to fail are not getting deleted.
Relevant answer
Answer
the reason for your error is something different...this VUMAT in itself is erroneous...this is done intentionally as it cannot be used without the knowledge... like for example nDmg = nDmk + lDmg is updating the damage however lDmg is not defined in entire script. instead lfail is defined. there are any issues like that....you can watch the video here
  • asked a question related to Failure
Question
3 answers
Is Not More Than 15 minutes disintegration time a hard and fast limit for immediate release tablets? does it depend on release mechanics, BCS class of drug, in vivo mimicking? If an immediate release tablet goes beyond 15 minutes disintegration, is it an absolute failure or it can otherwise be justified?
Relevant answer
Answer
One of the landmark criteria for dissolution is NMT 15 min (other are 30 min, 45 min) might be responsible for disintegration limit as well.
For rapidly dissolving products containing highly soluble drugs throughout the physiological pH range (pH 1.2 to 6.8), dissolution limit is > 85% in 15 min at pH 1.2, 4.0 and 6.8. Means considering dissolution at 15 min could be one of the criteria which can be linked to disintegration. As we aware the step of dissolution i.e. Tablet --> (disintegration) --> Granules --> (disintegration) --> Fine particles --> solubilization.
  • asked a question related to Failure
Question
6 answers
Archimedes was a Greek mathematician and the first to understand the operation of the lever arm mechanism. He had said the familiar phrase to show the power of the lever arm (It was said by Archimedes (287-212 BC) and it means "Give me a place to stand and I will move the earth" And we come to the current state of construction, where the load-bearing structure of reinforced concrete consists of columns, walls and beams, extending in height and width, ie by huge lever mechanisms that multiply the great forces of the earthquake. These huge levers of height (columns) and width (beams) join at the nodes creating a galaxy of opposite moments raised by seismic displacements and multiplied by the mechanisms of the levers. These torque forces are called to pick up the cross sections of reinforced concrete around the joints. Of course it is impossible to ignore these stresses concentrated at one point of the cross section (the one that fails first, critical failure area) and civil engineers have devised some techniques to trick the cross section failure at this point of the shear failure. One of these tricks is called elasticity. When the displacement of the structure is small, within the limits of the elasticity of the columns and beams the construction does not present failures. That is, they design the construction so that it works like a spring which stores and releases energy in the opposite direction. But when the earthquake is big and the displacements increase and the elasticity of the elements is not enough, they start to show leaks (small cracks) Here begins the second trick used by civil engineers to trick the great failure of cross sections and is called plasticity. Basically what they want to avoid is the creation of a large crack, which predisposes the collapse of the structure. They prefer to create many but much smaller cracks so that the construction does not collapse. They achieve this by placing dense transverse reinforcement (hoops) placed near the ends of the elements where they frame the node. If the earthquake is very large and the elasticity and plasticity are not enough then they use another trick which is called satisfactory design. Basically what they do is design the columns and the walls to be stronger than the beams. So the first thing that fails is the beam. And they do this because when the beam fails it releases seismic energy without falling because it hangs on the steel reinforcement, while if the pillar fails first with an oblique / form of failure it takes it all and leaves. These are the three defenses of construction today (elasticity, ductility, good design) that do nothing but try to overflow the displacement so that it is greater than the displacement of the earthquake.
Relevant answer
Answer
Stimulating topic
  • asked a question related to Failure
Question
4 answers
All civil engineers know that inertial stresses create deformations that cause failures and collapse of structures. Deformation can be caused by three different factors 1) The greatest deformation is created by the overturning moment of the wall and by the bending of its trunk 2) The second deformation is created by the torsional buckling that is observed in asymmetric, in high-rise constructions and in metal constructions. 3) The third deformation is created by the inhomogeneous subsidence of the ground (with or without earthquake), which deforms the nodes of the structure. THE SOLUTION 1) The walls under the imposition of compressive stresses on their cross sections through prestressing, do not create a bending deformation capable of creating shear failures. Conclusion Pre-tensioning must be applied to the walls. However, the prestressing increases the already great rigidity of the wall, and this has the effect of lowering (like a strong lever that it is) large torques at the base and at the nodes where it is connected to the beams, causing them to break. That is, as rigid, the wall is easily overturned and creates large moments at the base and at the nodes where it is connected to the beams, resulting in their breaking. Conclusion In order not to overturn the wall, we must connect it with the ground 2) Proper dimensioning of wall sections as well as the imposition of compression on their sections reduce torsional buckling 3) We must improve the quality of the soil by compacting its material, if we do not want subsidence The patent applies anchoring to the ground, compacts it, applies compression to the wall cross-sections and stops wall overturning, wall bending, torsional buckling and ground subsidence. What else do you want the patent to do, other than control the deformation that causes failures?
Relevant answer
  • asked a question related to Failure
Question
2 answers
I'm looking for any references that include failure reports for the Inova Endopore implant platform.
Relevant answer
Answer
Thank you for your response. This article reports successful results. What I’m trying to find is an article reporting negative results (high % of implant failure) and I have not been able to do so. If you know of any negative reports, I would appreciate the reference(s).
  • asked a question related to Failure
Question
4 answers
Hello! can someone help me please?
I'm simulating a tensile test with flat specimen in Abaqus explicit using JC plasticity and JC failure criterion. I need the strainxstress curve, a need the total strain not only the plastic strain, but in the "creat xy data --> ODB field output" doesn't appear the E. But I have selected it in the "Field Output Request"
Relevant answer
Answer
Hi Juliana, you should settle down Logarithmic Strain (LE) in field output and consider (LE) results after completed running
  • asked a question related to Failure
Question
9 answers
Hello
I have a question regarding the damage mechanics and strength prediction. Could anybody explain me the exact difference between damage mechanics and the failure criteria? For instance, there is a method called ply discount I exactly do not know whether it is used for the prediction of the failure or progressive damage?
Thanks
Relevant answer
Answer
Failure criteria, e.g. Maximum Stress alluded to earlier, require the tensile and compressive strengths of the lamina in each normal direction, i.e. 1, 2, 3, and shear directions, 12, 13, 23 (for plane stress, often assumed for laminate analysis, the coordinates 1, 2, 12 will suffice). These strengths be determined by straightforward tensile, compressive and shear experiments or from micromechanics (i.e. calculated based on strengths/properties of fibres and matrix and their associated volume fractions). If determining the lamina strengths by experiment we do not need to know the individual constituent strengths - we treat the material as homogeneous at the lamina level.
When analysing damage at the micro-level you will need to know the properties of the individual constituents.
  • asked a question related to Failure
Question
9 answers
The inelastic behavior of structures is not a choice of seismic design today, but it is an inevitable fact that they are unable to control in large earthquakes. I can control the behavior of the structure because I introduce into the structure an external force coming from the ground (without the presence of a mass that increases the intensities) in response to seismic shifts. I deflect all the axial forces that develop on the wall into the ground, while today they send them on the cross-sections of the beams and after being deformed excessively, they fail. Another very serious thing is that I control the bending, increase the ability to receive the cutting at the base by 50% and improve the foundation ground. I also eliminate the shear failure of the concrete that appears on the concrete and steel interface due to the tensile strength of the steel which turns the failure into a shear shape that is extremely brittle, and is the result of the concrete cooperation mechanism with the relevance.
Relevant answer
Answer
I agree with Dr Ioannis . It is an excellent idea. Thank you Dr Ioannis.
  • asked a question related to Failure
Question
2 answers
Used in Abaqus for displacement at failure.
Relevant answer
Answer
Dear @Abdullah
Below-mentioned literature link may be useful:
  • asked a question related to Failure
Question
3 answers
The MA-HFACS framework helps to distinguish active failures and latent failures involving
in the existing accident reports.
Relevant answer
Answer
Dear Eslam, thanks for asking this interesting question. Although I'm not an expert in this field, I think that the following relevant references could be helpful for your analysis. Please have a look at these interesting papers:
A Human Factors Analysis Method for Maritime Accident Evolution Using HFACS-EI Model
The Role of the Human Factor in Marine Accident
Both papers have been posted as public full texts on RG. Thus they can be freely downloaded as pdf files.
Also please see:
Offshore Transport Accident Analysis Using HFACS
As you can see, it pays off to search the "Publications" section of RG for helpful articles.
Good luck with your qoek and please stay safe and healthy!
  • asked a question related to Failure
Question
9 answers
As all know, in successful pre clinical cancer experimental studies, only 8% could be successful as well in human studies and clinical trials.
Can you reverse the previous statement, expecting successful data in clinical trials although of failure in pre clinical studies?
Relevant answer
Answer
Yes, now I understand what you actually meant Khaled M.E Elawdan . I fully agree with Tomasz Grabowski especially the paragraph below.
Another difficulty is the complex nature of the disease. The more complex target disease in its etiopathogenesis in humans, the more difficult it is to verify a drug candidate in the preclinical phase. Moreover, the etiology of many diseases is not exactly known, therefore many drugs are only symptomatic drugs. The symptoms-effects observed in the models may not be properly selected in the preclinical phase and generate an error. After all, there are many examples of drugs discovered by accident or drugs which, depending on the dose level, have different mechanisms of action. All of this can lead to the situation you are writing about.
Tomasz Grabowski as you mentioned it is going to be risky.
Thank you Khaled M.E Elawdan for a good question.
Best Wishes.