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- How to make a microcracks on polymer materials surface? I am focus on the seal-healing materials. I need to generate microcracks on the surface of polymer materials. Which method can be used to fabricate microcracks? I hope the width of microcracks can be constrained to between 100-500 nm.
Depending on how the final result should be the different techniques may be used.
Among them, the surface treatment by the heavy xenon ions irradiation at different angles
Or surface treatment by an ultrashort pulse of laser lightFollowing
- How do I set maximum and minimum velocity value in a PSO algorithm?
I am using PSO algorithm to search optimum value for parameters within range. I have 5 parameters such as: x0, x1, x2, x3, x4, and x5. Each parameter has own range.
x0 = [10,320]
x2= [1, 16]
x5 = [150,230]
In program, I am setting the lower and upper position as:
X0-min = 10;
Similar for the other parameters (x1,x2.....).
As, in PSO the particle position is changing based on velocity. I am confused on configuring a value for the velocity. How I can control velocity of a particle. I mean how to set limits of the velocity for each parameter? Should I use similar value for v0-min and v0-max as I used for the x0-min and x0-max?
A simple rule of thumb is to set initially the maximum velocity for each Design Variable at a value equal to 10% of Xmax-Xmin and make some preliminary runs. Keep track of the time histories reporting the velocity of the particles and a) increase by a small amount the maximum velocity for speedier convergence if the maximum velocity is reached often or b) decrease otherwise.
The "optimum" value is also problem depedent. If you have a vague idea about the shape of the objective function then a) choose a small maximum velocity in the case of non-smooth objectives to avoid overshooting and b) choose a confortably large value otherwise.
Please bear in mind that in literature values up to 20% or even 40% of the Xmax-Xmin are reported for different problems.Following
- Can the “non-standard analysis” related theory solve those defects disclosed by the suspended infinitesimal paradox family?
Theoretically and operationally, the theory of “non-standard analysis” is exactly the same as those of “standard analysis” in nature; it never solves those defects disclosed by the suspended infinitesimal paradox family at all and it is impossible for “non-standard analysis” to become the future mathematical analysis.
1, it is just because nonstandard structures is constructed within the confines of present infinite related theory system that make it have “deep structural equivalence” with “standard analysis”. So, in infinitesimal related mathematical area, it is unable to solve any problems and defects disclosed by the suspended infinitesimal paradox family at all and it is impossible for “non-standard analysis” to become the future mathematical analysis.
2, although it is for sure that nonstandard structures can do nothing in solving any problems and defects disclosed by the members of suspended infinitesimal paradox family (such as Harmonious Series Paradox), we still have another trouble: how does nonstandard structures solve problems and defects of “infinite-big” in present infinite related theory system?
Is the nonstandard structures just purposely constructed for the infinitesimal related "tyranny of epsilons and deltas" formal language only?
- Does anyone has the manual for the OPHIR pyroelectric sensor PE10-S?
The product is discontinued and I can't find my manual. Thanks.
Take a look at the attached file...let me knowFollowing
- How do you conduct desert soil reclamation?
Does anyone know about the mulching options for desert soil (arid to semiarid condition soils as well)? Also, have any researches done reclamation in a desert soil? Any good practices?
Thank you so much.
For semiarid soils you can use legumes of short cicles (using irrigation systems or rainy season) as green fertilizers. Incorporated in soil. It will help with time. If you use joinly with vermicompost the process will be fast.Following
- How can we measure the porosity of a material after its fabrication?
I want to measure the porosity of an alloy after powder-metallurgy, by variation in the compaction pressure. Please suggest different method.
The most effective and popular method to get the porosity by calculate the theoretical density of the material and then measure the actual density by any method such as Archimedes method the you can get the porosity from calculate the difference in the densities values divided by the value of the theoretical densityFollowing
- What's the probability of getting spontaneous mutations in chloroplast genome that'd confer resistance against both spectinomycin and streptomycin?
While performing chloroplast transformations, I've got plants which do not carry the antibiotic resistance marker (that should have been the case with the true transformants but are growing happily in spectinomycin, even in the presence of both spectinomycin and streptomycin.
Resistance could be due to spontaneous mutation that occurred in two different regions of the chloroplast rrn 16 gene, which codes for 16S rRNA. Plants whose antibiotic resistance is due to spontaneous generation are phenotypically indistinguishable from transgenic plants. Thus it should be noted that mutant plants may arise during generation of transplastomic plants and that additional molecular analysis is necessary for their identification and elimination [Filipenko et al. (2011) Spontaneous spectinomycin resistance mutation of the chloroplast rrn 16 gene in Daucus carota Callus lines. Russian Journal of Genetics, 47(1): 35-40].
Wishing you success in your reserach.Following
- How might forest and farm producers best be represented in the myriad multi-sectoral platforms that decide things on their behalf?
The Forest Farm Facility is strengthening forest farm producer organisations - in part to help them engage in decision-making (see attached report) - but what experience do you have about which platforms it is best to engage and how (Food Security, REDD+, FLEGT, landscapes etc) ?
Have you looked at using Bourdieu to help theoretically. Check out the article by Raedeke et. al.Following
- Can anyone share materials on "Feminism and Penis"?
How have or do [African] feminist scholars conceptualize penis?
- Can anyone suggest a research paper on sociology of sinkhole disaster?
It seems sinkholes related disaster sociology is very limited.
Alamdar, F., Kalantari, M., & Rajabifard, A. (2014). An evaluation of integrating multisourced sensors for disaster management. International Journal of Digital Earth, (ahead-of-print), 1-23.
Tierney, H. (2014, July). The New Sociology of Disaster: Inequality, Vulnerability, and Resilience. In XVIII ISA World Congress of Sociology (July 13-19, 2014). Isaconf.
Vollmer, H. (2013). The sociology of disruption, disaster and social change: Punctuated cooperation. Cambridge University Press.Following
- What do you think will be the importance of emotions on context-awareness and IoT in the near future?
Applications, in particular mobile applications, try to provide the most suitable information for users and to react accordingly to user's needs. In this sense, emotions are a relevant aspect to establish the best way to interact with a user and IoT could help in providing that assessment. In this context, what is your vision on the importance of emotional assessment for the near future in mobile applications?
One of my current projects is in the field on behaviour change technology, a field within HCI. The use of emotion to persuade people is more powerful than logic. Targeting peoples emotions brings up many ethical issues in this field. There are new sensors on the market that are able to detect how people are feeling (http://vandrico.com/device/interaxon-muse). Using these sensors, it would not be too difficult to develop apps that respond to how people are feeling. The potential for these devices are enormous.Following
- Does anyone know how to reproduction of Vaccinium artostaphylos L. (worthberry) with tissue culture method?
Does anyone know how to reproduction of Vaccinium artostaphylos L. (worthberry) with tissue culture method?
What is the best media fore reproduction of worthberry?Following
- How to diagnose the uterine septum in a noninvasive way?
Does anyone knows MRI and ultrasound in the evaluation of uterine septum or bicornuate uterus?
Dear Artur thank you for your kind submission. I'll look at it. I wish Merry Christmas again and a Happy New Year. FrancescoFollowing
- How do nanoparticles enter into bacterial and animal cells?
What are the various routes they take to enter cells?
Like they may enter through ion channels or by some other physical ways
Have a look at this review paper, it describes pathways of cellular uptake which are relevant to nanoparticles.Following
- What is the best composition of microorganisms (acidogenic and methanogenic) in a biodigester?
What is the best composition of microorganisms (acidogenic and methanogenic) in a biodigester?
Hi, this is a tricky question and in my opinion there is no straight answer.
In my research I have done metagenome analysis of sludge from several biogas reactors and generally the proportion of identified bacteria / methanogens is around 90-95% bacteria and 10-5% methanogens. However, in some metatranscriptome analysis we have seen that even though methanogens are less abundant they are extremely active, representing around 25-30% of the active community.
In my opinion it is not so important the proportion of bacteria/methanogens you have and what is important is that you operate the digester at the best optimal conditions for you specific inocula and substrate, and as Juan and Iulina point out depending on your goal you should adapt your community accordingly.
I hope this helps.Following
- When and where do we use the term drought and water deficit stress?
Quite often it is said that if we write studies to understand the drought tolerance of coconut or some other crop it is not correct. Please clarify this.
Both are synonyms although Water deficit is more commonly applied in scientific literature where it relates to water availability below field capacity and it is used especially in relation to crop cultivation. On the other hand drought is generally related to low precipitation over a period of timeFollowing
- We have tried coating Nickel film on glass and it turned out black. Why?
In our lab we have tried coating a nickel thin film on glass using DC magnetron sputtering in Argon plasma environment. But it turned out to be a black layer. What might be the reason? We have even tried coating on stell substrate.Even then the layer was black in color.Why?
Another explanation is contamination with tin or zinc.Following
- I'm looking for a server to validate the 3D-structure modeling of my protein. Do you have any suggestions?
My protein sequence has been modeled by swiss-model server. How can I validate the result?
All the computational method only tells you how your modelled structured not violating some kind of metric. You cannot say the structure is valid because they look good in the validation servers. As structure modelling bases on the sets of criteria, they will look good those validation methods anyhow. You need experimental evidences.Following
- How graph union has more effect if there is a change in smaller graph? Could any one explain it with set theory example?
Please Relate the set theory to graph theory.
If the subgraph is induced (all edges of original graph with both ends in the subgraph are included) then the same problem cannot be simpler for the whole graph than for the subgraph. Otherwise, there is no relation; all graphs are subgraphs of complete graphs..Following
- Any suggestions regarding Vitamin E hydroquinone carbonate polymers (i.e. synthesis or structure information such as MS, NMR, etc.)? I am trying to identify an impurity that I think is the carbonate polymer of alpha-tocopheryl hydroquinone based on NMR and MS data. I would like to confirm my proposed structure with leading references by an alternate safe reaction. However, I am not able to find any reliable synthesis or structure data.
- Can anyone provide me with a recently developed observation checklist for communicative classrooms?
I'm working on developing an observation checklist for junior high school English classes. I'm looking for new checklists developed elsewhere to see how I can fit the items to my own context. Nearly all the research papers I can find have based their works on COLT observation scheme but I could not found other checklists adapted or developed for local use.Following
- How can I prepare a chitosan emulsion formulation?
I am currently using chitosan powder and acetic acid. Chitosan powder is of 70% and 90% deacetylation.
I am getting problems in 10% solution preparation it is not dissolved properly. Kindly suggest me additives to increase solubility.
- Is there any procedure or method to rear cecidomyiidae under lab or net house conditions?
Hi, I am working on midge fly, cecidomyiidae. Can anyone provide me a procedure or method for rearing cecidomyiidae under lab or net house conditions?
- Is it possible to have an adsorption system that does not follow Langmuir or Freundlich isotherm models?
I'm fitting my isotherm data to linearized langmuir and freundlich isotherm models. But they didn't have a good fit with these models. But data showed a good fit with dubinin-radushkevich and Temkin isotherm models is it possible?
I will also say "Yes" sure! But, could you give some idea about your adsorbent/ adsorbate system? This may ease the selection.Following
- Is Integrin Peptide available as a topical medication for age-related muscular degeneration? Integrin peptide is under evaluation as a intravitreal injection.
- Is there a useful method to measure the contribution of marketing mix for a product in different markets?
I would like to find some similar studies, about this topic.
Dear Miss Golami,
Please find a copy here enclosed.
- How much maximum amino acid can we couple without using any aggregation technique in Solid Phase Peptide Synthesis?
In Solid Phase Peptide Synthesis, maximum how much length are we able to perform? Somebody have did up to 32 residue without using any special technique. Can anyone make this clear to me?
you may seeFollowing
- Which one is the best ref electrode between Ag/AgCl and Cu/CuSO4 for laboratory measurement?
I want to do a laboratory project for measuring thermoelectric potential. So, which one is the best reference electrode between Ag/AgCl and Cu/CuSO4 for measuring thermoelectric potential? Why?Following
- How to ensure consistency condition (determine active slip systems) when implementing gradient crystal plasticity theory?
I am currently implementing gradient crystal plasticity theory for my research. As shown in literature, slip should be treated as nodal degree of freedom in order to compute its gradient. In that case, unlike conventional plasticity, where slip is treated as state variable and computed at each integration point, slip is solved globally.
My questions is: in conventional plasticity, we have return mapping algorithm to determine the active slip systems. In gradient theory, how do we determine active slip systems, since slip is treated as nodal dof ? How can we make sure slip is zero when that slip system is inactive ?
Thank you very much.
Thank you both very much for the reply. I still have some follow-up questions:
For Dr. Karthic R. Narayanan :
I am using my own code but it is similar to a UEL. Could you please be more specific on how people use UMAT to implement gradient theory? As my understanding, UMAT could only take care of local state variables (i.e slip in the current integration point), while in gradient theory there is the need to know some non-local state variables in order to compute the gradient (of slip).
For Dr. Hojjat Badnava:
I've gone through the paper and it is very helpful. However it involves some manipulation in the element stiffness matrix when the integration point is in the elastic regime, mainly by placing some artificial value to the hardening modulus. I am wondering if there is any other method because I am using crystal plasticity, so manipulation with element stiffness matrix would be much more complicated.
Thank you very much.Following
- How can I remove SUMO-0.21.0 in Ubuntu 12.04?
I want to install SUMO-0.12.3 in order to use MOVE. As I execute command as sudo apt-get remove sumo error comes as unable to locate package sumo.
I have already tried the command sudo apt-get update. I have attached the file below.If anyone can help with it.
First, try sudo apt-get purge sumo sumo-doc sumo-tools. Then, try synaptic package manager.Following