Science topic

SPC - Science topic

Explore the latest questions and answers in SPC, and find SPC experts.
Questions related to SPC
  • asked a question related to SPC
Question
12 answers
Question-5: Are Stored-Program-Controlled (SPC) computers (von Neumann, 1946) adequate enough for intelligent software design and implementation? If not, what kind of computers will be needed for the next generation of autonomous computing?
Relevant answer
Answer
It must be clearly understood that all common descriptions of mental processes and the functioning of the mental apparatus have little in common with reality and are not related to objective reality.
In reality, all living beings are subjective systems simply by virtue of being enclosed in shells. For the same reason, they cannot have direct knowledge of the world around them and have to form their behavior, in all its aspects, on the basis of their own subjective representations.
For humans, the processes associated with the formation of behavior go at a speed that is four orders of magnitude higher than the speed of the processes leading to situational awareness of the results of behavior. It is this process of situational awareness that is perceived as thinking since the very process of forming behavior is hidden from perceiving.
In my opinion, only by being in such a position can one understand how the behavior of living beings in general and a person, in particular, is formed.
As for intelligence, remember on what basis you make a conclusion about the presence of the intelligence of the interlocutor and how this is connected with his internal properties. It will be more convincing than reading my explanations.
  • asked a question related to SPC
Question
6 answers
Does this area has the potential for research?
Relevant answer
Answer
I think the main reason is related to their complexity. For example, I tried hard to reach the result of the following paper:
but I was not able. Although better results than conventional monitoring methods may be acquired, Bayesian methods lead to several complexity.
Best regards.
  • asked a question related to SPC
Question
1 answer
I am trying to run simulations of PNIPAM on GROMACS to capture the LCST behavior of the compound. However, I am running into issues. I obtained my topology using the TINKER toolbox for OPLS/AA and I am using SPC/E water along with it. I have attached my topology to this question.
I am seeing some really strange behavior. For a syndiotactic 30-mer, I am seeing a collapse of Rg (radius of gyration) from about 1.6 nm to 1 nm in about 10 ns at 295 K - 315 K, and the system seems to prefer being there. This would be understandable, however, when I bump the temperature up to 330 K, the Rg value does not stabilize around the 1 nm mark but keeps going back up. Simulations at 360 K again show a stabilization around 1 nm for Rg. The polymer is swollen at 280 K and has an Rg of about 1.7 nm.
Does anyone know what could be the reason for such behavior? Would anyone have a working topology (.itp) file that I can compare with? I am running out of things to try.
Relevant answer
Answer
Most molecules can easily be pieced together from existing building blocks; they are generally quite transferable.  There are various tools out there for OPLS, like MKTOP, TopolGen, etc. you can also give a try to gmx x2top tool in gromacs. It will give you a primitive compatible topology to OPLS-AA force field, but try Justin's suggestion first.
Use Topolbuild package in gromacs. It will help you to generate topology of any molecules, and it will create all necessary file to run simulation in gromacs.
  • asked a question related to SPC
Question
2 answers
Hi I simulate the electro-osmotic flow (EOF) by LAMMPS. first, create saltwater 1 molar(NaCl) and add sodium ion and all system charge neutralization with an additional charge on the channel atoms uniformly. In all cases, the system equilibrates for 2 ns, after that at 0.025 volts/Angstrom electric field run10 ns to ensure that a steady-state reach and then an additional 30 ns execute for collecting data and statistical averaging. in my simulation: all pair style  is Lj/Charmm/Coul/long 8 11 time step 1fs water model is SPC/E update neighborhood list every timestep without delay We have not any problems when Na+ ions are low concentration. The problem makes cause when we have more than 60 Na+ ions in solution. In the latter case "lost atom" is observed. changing timestep, increasing simulation box length were not removed the error.
Relevant answer
Answer
I do use LAMMPS for Granular.
I will tell you my experience, might be helpful for you as well.
First, need to find out from where these atoms are getting lost - Crossing any boundary (fix BC cause this)
Second is to check on timestep. As you mentioned changing the timestep didn't make any changes, this may not be the reason.
Also you mentioned - increasing the concentration of particles gave this error. It is highly likely that -- pair potential is not defined well.
In case if you want to ignore lost atom (if it is not high), you can always use thermo_modify lost ignore
  • asked a question related to SPC
Question
1 answer
My current research is about SPC and I'm interested in tuning strategies for these types of predictive control approaches. The cost function is on the photo and the tuning parameters are Np (prediction horizon), Nc (control horizon), Q (weighting matrix for error tracking), and R (weighting matrix for control effort). How can I select these parameters to guarantee a desired closed-loop performance? Do you have a paper to recommend me? Or any idea how to get started?
Relevant answer
Answer
Hi Victor,
You can find Q and R tunning in all optimal control text book. For Predictive contrt, the best reference to start is Wang's book:
Wang L. Model predictive control system design and implementation using MATLAB®. Springer Science & Business Media; 2009 Feb 14.
I hope this would be helpful for you.
Regards
  • asked a question related to SPC
Question
4 answers
Does anybody know references to MD and/or MC studies on the "saturation vapor pressure" of water done with the SPC/E water model? To be specific, I would like see to a benchmarking of the simulation results to the experimentally determined vapor-presure line of water in the temperature region between 273 and 373 K?
Relevant answer
  • asked a question related to SPC
Question
3 answers
Hi,
I am currently working in a project on extracting REE from ionic clay sources and wondered whether SPC can be used to determine the process capability of the extraction. For example, plotting recovery rate of 30 trial runs of extraction and calculating Cpk value?
Relevant answer
Answer
how measure recovery how the different unit of recovery data points spread you need to put recovery data points in a linearity equation, you need to see variation among recovery output (measured units) are statistically significant or not
this verification method called normality checking.
basically i need to understand what is the unit of recovery how you quantity unit of measurement is more important for any application of statistical tools
  • asked a question related to SPC
Question
7 answers
I'm an master student of advanced information systems and my bachelor degree was in industrial engineering. My field of interest in industrial engineering was quality related topics like SQC, SPC, DoE, Six Sigma, etc. Now I'm looking for a proper topic for my master thesis which combines Data Science and Quality related topics.
Relevant answer
Answer
Quite often, QC data can be significantly unbalanced. I had a data set with 20+ variables and 100,000+ subjects from a line of a particular product, and 100-120 of the subjects came back for warranty work. The goal was to find the important variables to help predict which products would come back for warranty work. All the standard statistical methods failed. I didn't.
Maybe you can find a data set that has highly imbalanced data (Like cancer) and find something interesting.
  • asked a question related to SPC
Question
8 answers
Hello,
I am a novice researcher in the field of clustering algorithms. DBSCAN was the one which its mathematical background draw my attention to itself but unfortunately, except biological- and medical-oriented fields, I couldn't imagine any other use cases for the algorithm. I would appreciate if anyone introduce me some useful resources which DBSCAN is used in fields except medical or biological ones. According to my bachelor degree (Industrial Engineering), I'm particularly looking for industrial and manufacturing instances.
Regards.
Relevant answer
Answer
Let’s think in a practical use of DBSCAN. Suppose we have an e-commerce and we want to improve our sales by recommending relevant products to our customers. We don’t know exactly what our customers are looking for but based on a data set we can predict and recommend a relevant product to a specific customer. We can apply the DBSCAN to our data set (based on the e-commerce database) and find clusters based on the products that the users have bought. Using this clusters we can find similarities between customers, for example, the customer A have bought 1 pen, 1 book and 1 scissors and the customer B have bought 1 book and 1 scissors, then we can recommend 1 pen to the customer B. This is just a little example of use of DBSCAN, but it can be used in a lot of applications in several areas.
  • asked a question related to SPC
Question
4 answers
Reduce the effect of autocorrelation when designing control charts
Relevant answer
Answer
Thanks dear Mohad. I really appreciate.
  • asked a question related to SPC
Question
4 answers
I'm analyzing statistical process data (SPC) of pharmaceutical product parameters and found some out of control results.
The type of control chart that I use are X-bar-R, X-bar-S, and X-MR. May you share your formula, because their range of UCL-LCL are so narrow.
Relevant answer
Answer
As you have mentioned that you found some out of control data, it clearly indicates that your problem is to set the control limits for the process. This is called phase-I or the base period. In the base period , when the process shows points beyond control limits, it is required to find whether they are due to assignable causes or not. It requires to remove those points from the analysis. Then one goes into phase-II where the chart will be used to monitor the process.
Also, do not get confused with specification limits and control limits. Because I found some practioners are confused between USL and LSL with UCL and LCL. Please refer to Statistical quality conrol book by DCMontgomery for better understanding.
  • asked a question related to SPC
Question
12 answers
I'm preparing liposomes from SPC and Na cholate & realised that the zeta potential reduced to -10 from -35 by adding a protein solution. Is there any way to increase zeta potential? Is zeta potential >+/- 30 needed to stabilise liposomes?
  • asked a question related to SPC
Question
3 answers
I had ran molecular dynamic simulation on apo protein using TIP3P, TIP4P, TIP4PEW and SPC for 25 ns to establish the most suitable solvent model for specific protein. However, none of them gave low RMSD value. The lowest RMSD value is between 3.0 - 3.5 for TIP3P. But when I ran the protein with the ligand, the RMSD value become higher around 3-4. So what other parameter that I need to consider to establish the model?
Relevant answer
Answer
So you start from a crystal structure and also using this for the RMSD? Have you carefully heated up the system? Are you sure your temperature was at reasonable levels at all time. What FF are you using for the Protein.
I do have concerns that the reason for the high RMSD is related to the solvent model. Can we have a PDB?
  • asked a question related to SPC
Question
4 answers
I am simulating water by SPC/E model. I'm using fix_shake command but it is not working. "Unknown fix style shake" is the error message. From the manual I came to know that shake is a part of rigid package. But I am not able to install this package in lammps.
Relevant answer
Answer
You can install packages in Lammps by "make yes-name"
  • asked a question related to SPC
Question
3 answers
I want to know the basics of SPC. Using this how can I map the wafer?
  • asked a question related to SPC
Question
8 answers
There are two methods available for bacterial count.
1. Standard plate count.
2. Analysis by Spectrophotometer.
In both methods SPC is most suitable method because it count only live bacterial cells.
Apart from both, any other method is available which is as best as Standard Plate Count?
Relevant answer
Answer
Determination of cell numbers can be accomplished by a number of direct or indirect methods. The methods include standard plate counts, turbidimetric measurements, visual comparison of turbidity with a known standard, direct microscopic counts, cell mass determination, and measurement of cellular activity.
  • asked a question related to SPC
Question
5 answers
I got the OD value, how can I convert the OD value to percentage?
Relevant answer
I think the practical way is to measure the opical density with subculture to know how many cfu in your tube the continue with same technique like time series and i am sure you get the right number of bacteria.
  • asked a question related to SPC
Question
6 answers
hi,
i want to examine the relationship between more than two dependent variables and with one independent variable: for example , between a SPC implementation factors and their influence on the  management level? the focus is to excess whether management level practices SPC or not. Therefore,besides Canonical correlation what is the best inferential statistical method to use? , or can i use regression with dummy variables?Thank You
Relevant answer
Answer
Juehui, please explain your variables. It is not clear whether you have multiple independent variables and one dependent (management style) or if there are in fact multiple dependent variables (outcomes).
  • asked a question related to SPC
Question
2 answers
Does anybody have any idea on how to test for the signal resistance of a control statistic?
The control statistic is in the attachment.
Theory/lemma on how to achieve this is highly welcome.
Relevant answer
Answer
In statistical process control (SPC), Signal Resistance is a measure of inertia. which can be the measure of the resistance of a control chart to signaling a particular process shift.
Thank you