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  • Pooya Ghaderi asked a question in Vibration:
    Random vibration book?


    Can anyone introduce a good random vibration book?


  • Pooya Ghaderi asked a question in Vibration:
    Random vibration book?


    Can anyone introduce a good random vibration book?


  • Do you know any masterpieces of art which are devoted to anti-war themes?

    One of the main tasks is to cultivate peacemakers. Anti-war arts (painting, sculpture, literature, music, photo) can be helpful in upbringing future generation. Cultivating a culture of peace through awareness of genius message (implicit and explicit) is important in schooling. We are going to research the sources, organize the conference and stage one of the creative works. We will be thankful for every contribution.    

    David Charles Wright-Carr · Universidad de Guanajuato

    In a similar vein, Bob Dylan performs his protest song in 1962; the lyrics are on the YouTube page, clicking on "Show more":


  • What's the interpretation of single photon interference in a double slit experiment?

    I want to know what are the reasons of this interference.

    How does quantum mechanics look for this interference? Does the photon interfere with itself or are the waves accompanied with it interfering with each other?

    What's the relation of wave particle duality with this experiment?

    What are the most acceptable interpretations of this experiment?

    Harry ten Brink · Energy Research Centre of the Netherlands


    You mentioned in another question in ResearchGate that you understood anti-bunching; apparently you do not have the slightest idea and refuse to read the even popularised literature on the item. I cannot take you seriously with your falling back on Huygens' pinholes

  • Ranjith Pathirana asked a question in Subculturing:
    How to maintain the embryogenic potential of a cell culture long-term?

    Why does my embryogenic cell culture losing its embryogenic potential after several subcultures? I try to maintain it growing fast by frequent subculture, selecting more dispersed cells, maintaining the same media composition, yet after several subcultures it doesn't produce as much embryos as it used to.

  • What are the methods for face detection in unsuitable lighting conditions?

    The methods for face detection that work well in unsuitable lighting condition.

    Mohammed El-dosuky · Mansoura University

    Dear Alireza Rahmani

    Why not considering 3D Face Recognition?

    Please read the rationale here 


  • M.T. Boudjiet added an answer in LCR Meters:
    What are possible reasons of change in LCR measurements ?

    We are using IET 7600 Plus Precision LCR meter in our lab for LCR measurements of different nanostructures (in pallet form). When we perform any measurement and repeat it within minutes, we get results with some changes. Is it due to some polarization which is induced in the sample when we apply electric field and it takes some time to be vanished after which we may get same results? Can any body please suggest me some reasons of this change ? Why can't we get same results? 

    M.T. Boudjiet · University of Bordeaux

    because they are nanostructures thay are very sensitive to the variation of temperature and humidity. You can avoid these phenomena if you put for example your samples in isothermal box or in vaccum

  • Pooya Ghaderi added an answer in Vibration:
    Can anyone Define the terms “vibration” and “wave” precisely?

    can anyone Define the terms “vibration” and “wave” precisely?

    Pooya Ghaderi · Rice University

    Wave is a vibration or disturbance that travels in the media.

  • Praveen S added an answer in Glass Substrate:
    Is a difference of 1 degree on XRD results between sputtered target and thin film significant?

    I sputtered a Ni-5.5Al (at%) target onto a glass substrate, suing DC magnetron. The thin film thickness is about 275nm.

    The XRD on both sputtering target (bulk) and the thin film suggest that the grain orientation consists of AlNi (110) and Ni (200). However, I noticed that:

    a) AlNi peak on the bulk is at 44.48°

    b) AlNI peak on the thin film is at 43.38°

    Attached is the XRD spectrum image.

    Is the 1° different siginificant? Based on Bragg's law, this will show a difference in the lattice parameter. However, I am wondering if the result I am getting is negligible and if I only need to take note on bigger difference (e.g. more than 5°)?

    Praveen S · Indian Institute of Technology Madras

    This shift could also be because of sample displacement error. Ensure it's not because of sample displacement error, then you can relate this shift to difference in the lattice parameter. Strain will cause a shift only if it's along one direction if it's random it will only broaden the peak. 

    Easy way to check if the shift is because of sample displacement error or lattice parameter change is to see how much the high angle peaks are shifted. Because sample displacement error is a function of Cos theta, and lattice parameter shift is a function of Sin theta. 

    By the way, One degree shift is significant. 

  • Chekkar Abdelghani added an answer in Engineering:
    Can you give guidance to be a supplier of Oil Refineries for Mechanical components like Valve, Flanges etc. what is the road map?

      I want to know what kind of test we need to clear for validate my products.

    Chekkar Abdelghani · Sonelgaz Spa

    en algerie l'industrie du gaz rt du petrol est en plein expenssion , il vous faut qu'elqu'un afin de mieux faire une approche avec ce marché . je peut vous accompagner . chekkar abdelghani

  • Eduardo Borba Neves added an answer in T-Test:
    How carry out the t test two independent sample controlled by a co-variable in SPSS?

    Is it possible? Carry out the t test two independent sample controlled by a co-variable in SPSS?

    Eduardo Borba Neves · Federal Technological University of Parana

    My Friends,

    Thanks for the answers!

    best wishes,


  • Pooya Ghaderi added an answer in Gaussian:
    Is vibrational frequency (other than due to anharmonicity) temperature dependent?

    How to calculate vibrational frequencies at different temperaturs? This can not be done on Gaussian.

    Pooya Ghaderi · Rice University


    You mean natural frequencies? If in a material stiffness is temperature dependent, then the natural frequencies will depend on stiffness.

  • Is there any evidence m_neutrino is not 0.09161 eV/c^2?
    My attempt at theory indicates m_neutrino ~ 0.09161 eV/c^2 - for all three neutrinos. The relevant result is (m_neutrino)*(m_tauon) ~ {(m_electron)^2}*{(alpha)^(3/2)}. Here, alpha is the fine-structure constant.
    I believe the result is consistent with S. Thomas, et. al., http://arxiv.org/abs/0911.5291 and roughly consistent with page 46 of J. Beringer, et. al., http://pdg.lbl.gov/2012/reviews/rpp2012-rev-neutrino-mixing.pdf .
    Perhaps people know of more data - favorable or unfavorable to the above result - regarding neutrino masses?
    (The attachment provides more information about the theory. See, especially, page 6, Table 2, items (12) and (14).)
    Thomas J. Buckholtz · University of California, Berkeley

    Permit me to post a follow-up note. And, again, thanks to people who participated regarding this question.

    I think I have sharpened my attempted research, in part to include possibly of being able to anticipate the extent to which neutrinos are Direct or Majorana fermions. The Dirac-and/or-Majorana result comes from math that seems to correlate with numbers of instances of elementary particles.

    Here is a summary of some findings.

    We predict masses {or mass-math eigenvalues} for neutrinos, of which 2 would be Majorana fermions (~0.125 eV/(c^2) and ~0.058 eV/(c^2)) and 1 would be a Dirac fermion (~0.058 eV/(c^2)).

    I am unable to determine uncertainty ranges for the masses. So, for example, a previous estimate of ~0.092 eV/(c^2) for 1 mass could be as good as the current ~0.125 eV/(c^2) for the same mass. And, the ~0.092 eV/(c^2) value might correlate with a sum of masses that is less than the astrophysics-based observations suggesting an upper limit of ~0.23 on the sum of the masses.

    I attach information related to this work.

    Again, thanks.

  • Satyabrata Sarangi added an answer in Calibration:
    What are the constraints in coming up with an accurate continuous and non-invasive glucose monitoring device?

    Though many research groups are active in making this device from so many years, why nobody has come up yet with a great accuracy? I know calibration is one of the toughest parts.

    Satyabrata Sarangi · University of California, Davis

    Thanks a lot Prof. Rababah for sharing this resource. It's a good article.

  • Does anybody know an ISI journal with quick process in the area of natural computing, artificial immune systems, biologically inspired algorithm?

    I'll appreciate if somebody introduces me a good ISI journal with quick process time. My paper is in the field of artificial immune system, biologically inspired algorithm, natural computing, and pattern recognition.

    Thanks in advanced 

    Mohammed El-dosuky · Mansoura University

    Dear Sajjad Fouladvand

    You can consider IEEE transactions.

    There are pay journals (response in 6 weeks) and free-of-charge journals that takes about 6 months.

    Applying your work in a domain (such as medical applications) may increases the possibility of publishing your work in other journals 

    If you build a software package, I recommend JMLR (Google it)

  • Douglas Glenn Chang added an answer in Orthopaedic Sports Medicine:
    What do you think about the MR-artrography of the hip?
    The injection of intra-articular contrast could be beneficial for the study of intra-articular pathologies of the hip, such as loose bodies, osteochondral lesions, articular cartilage or acetabular labrum with emphasis on femoroacetabular impingement.
  • Do you think whether it is proper to connect gravity exclusively with the speed of light?

    Since the beginning of the twentieth century the speed of light is thought to be fundamental to gravitation and its transmission effectiveness. Mathematical physics seeks whether this idea is sufficient for explanation of all phenomena related to mass attraction. Is a change of position needed? What is your opinion?

    Arno Gorgels · Principia Naturae

    Kindly, define what you consider to be a universe, dear Marwan? I appreciate your opinion.

  • Can someone tell me the diseases that the receipients of embryos must be free from?

    For bovine embryo transfer program Which diseases the Donors & receipients must be free from?

    Firas M.A Al-Rshoud · Hashemite University

    I do agree with Erma, as the maternal health should be opitimized before planing for pregnancy,as any pre-exicting condition my impair implantation and will increase miscarriage rates if implanted.

  • Can anyone suggest the endochitinase enzyme activity assay from paenibacillus strain?

    I have zone of clearance on Collidal chintin plate but I am not getting enzyme activity when inoculated from broth. I am using DMAB method. Is there different assay methods to differentiate between endochitinase and exochitinase. should I use different method or any other analytical method. Please suggest?

    Vikas Sharma · The Energy and Resources Institute

    Dear Micheal and Lorenzo...Thanks for your suggestion

    @Micheal: We are putting Chitin in the broth...minimal media with yeast extract....standard protocol

    @Lorenzo...We didn't observe the outermost parameter....I will definately have a closer look..Thanks

    However unfortunately we are not getting the production also....we are not able to see any sugar production in supernatant also...we are using DMAB method for estimation

  • How to build a truth table and combinatorial circuits about a sudoku puzzle?

    Hello everyone, I'm currently researching on building a truth table and combinatorial circuits for the sudoku puzzle. Recently, I'm reading some of the books in discrete mathematics but can anyone help me on how to get started in this research? Any tips about the proofs and logic of this puzzle? A little help shall be much appreciated :)

    Daniel Lichtblau · Wolfram Research

    To make specific what @Armin Fügenschuh has noted, it can be cast in terms of 9^3 0-1 variables. Each of the 9^2 positions has nine variables, all but one must be zero, and that last records the value of that position (e.g. if x[1,1,4]=1 then the (1,1) position contains a 4). So the exclusions come from the constraint that the "position sum" be 1. Then there are constraints from rows, columns, 3x3 subsquares; each of these giving 9^2 equations Those values that are given then reduce the system and your ILP solver does the rest.

    One can instead use 9^2 variables, each from 1 through 9. But this formulation does necessitate using some method for maintaining the needed exclusivities. Disjunctions are not the way to go. One should instead work with new variables, one for each pair involved in an unequal constraint; there is a standard way to go about this. But my (perhaps limited) experience is that the 0-1 formulation gives results faster for sudoku-type problems.

  • Kai Zhao asked a question in Lammps:
    Is there a free software to prepare LAMMPS input file?

    I know LAMMPSfe, but it is a little expensive for a student. MedeA and MAPS are more expensive.

  • Mihai Prunescu added an answer in Articulation:
    Can somebody give me some examples of phonemic variations in a language and the probable reasons for such variations?

    In Ghana, I have observed that the phoneme /j/ is realized as /dz/; /y/ or /Ʒ/ in speeches by individuals. I have also noticed that the difference in the realizations depends on either the absence or the presence of the target phoneme in the learners’ speech (i.e. transfer errors). Where it is present but the realizations are not the same, the learner tries to articulate the phoneme as a phoneme he/ she already knows. Where the target phoneme does not exist in the already known languages of the learner, he or she tries to make a substitution with another phoneme that exists in his or her linguistic repertoire. Can someone share with me some example of phonemic variations that he or she has noticed in their students’ speeches? Are the reasons for the variations different from what I have stated?

    Mihai Prunescu · Institute of Mathematics of the Romanian Academy

    Someone such variations are determined by areas of speakers. The romanian word "pe" (on) is spoken around Bucharest like " pă". There are towsends of such area dependent prononciations in many languages. In German, the past perfect particle "ge" is spoken in the Berlin area like "ie" (written je). The expression "Hast du jedient" ("Have you served in the army?") instead of "Hast du gedient?" is classical.

  • How can I identify mouse movements patterns ?

    Fallowing data available for mining and pattern recognition

    X coordination of the cursor with system time
    y coordination of the cursor with system time
    ( System time for every 100 ms )

    Each and every user's mouse movements data available for 30 min.

    How  identify mouse movements patters if exits among these user ?

    Mohammed El-dosuky · Mansoura University

    Dear Sachith Malinda

    I suggest considering signal processing. A good start may be the use of window functions http://en.wikipedia.org/wiki/Window_function 

  • Stefania Squadrone added an answer in Articles:
    Can somebody help me with article about Aspirgilliosis, its mechanism and so on??????

    Hi everyone!!! I want to know about Aspergilius fumigatus. Who can help me?

    Stefania Squadrone · The Veterinary Medical Research Institute for Piedmont, Liguria and the Aosta Valley

    There is a very interesting paper on PLOS Patogens (open access)

    A. Fumigatus-What makes the species a ubiquitous human fungal pathogen? By Kwon-Chung and Sugui, December 2013, you can start from this one....

    Best regards


  • Jenkins Macedo added an answer in ANOVA:
    Would you conduct the Least Significance Difference Test after results from ANOVA indicates that mean yield among treatments were highly significant?

    The analysis of variance (ANOVA) shows that mean yield among treatments used in an experimental trial were highly significant. However, the result did not show which of five the treatments yield were significant. Thus, to figure that out I conducted the Fisher's LSD pairwise comparison and the results revealed interesting trends and now we are able to tell (apart from just yield data at face value) were the statistical significance lies within and between treatment groups and replications. Do you think there would be another analysis that we need to compute that could provide additional value and meaning to the data?

    Jenkins Macedo · Clark University

    Bye the way, I sincerely appreciate the discussions, because it gets me thinking. However, hope things don't get too spice up. Thanks for the insights!

  • A. Soroudi added an answer in Scheduling Algorithms:
    Does anybody know of a method to further optimise the result of the greedy scheduling algorithm?

    After a result using greedy schooling approach has been calculated I would like to further optimise it (if necessary). Any ideas?

  • Which is more hydrophilic, respectively? Glucose, starch, ascorbic acid, chitosan or polyvinil alcohol?

    I want to coat this material on magnetic nanoparticles to stablize them. Which one is better or can you say there is a better option?

    Magdalena Zdanowicz · West Pomeranian University of Technology, Szczecin

    Starch derivatives are used to cover magnetic nanoparticles. Glucose and ascorbic acid are small molecules, so I am not sure, that they are suitable for coating http://www.google.pl/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&ved=0CEIQFjAF&url=http%3A%2F%2Fwww.ichp.pl%2Fattach.php%3Fid%3D264&ei=FPpwVKjfBsGiyAPtxYKACg&usg=AFQjCNFF8SawyV8c4nEaWqGRojScuDzeOw&bvm=bv.80185997,d.bGQ. Hydrophilic properties of chitosan depends on deacetylation degree and You schould take into consideration, that chitosan is water soluble in low pH (presence of acids can affect nanoparticles properties).


  • Adam B Shapiro added an answer in Molecular Biology:
    What is the possibility of expression of protein, which is naturally produced intracellularly to be produced extracellularly, and some examples?

    I am planning to work on production of a vitamin that is naturally produced intracellularly to be produced extracellularly. Is it possible as a hypothesis to be done? Was any experience on that? what are the main factors that would affect the success of the transport process?

    #Molecular biology #Genetics #Biochemistry #Microbiology  

    Adam B Shapiro · AstraZeneca

    Focusing on the extracellular protein expression part of the question, two important considerations are (1) getting the protein that is not normally exported through the export machinery successfully and with high yield and (2) keeping the protein reduced, as it would be in the cytoplasm, rather than oxidized, as it will become in the extracellular medium.

    It is not necessarily easier to prepare the protein when it is produced extracellularly than intracellularly. For normally soluble, intracellular bacterial proteins at least, if you can overexpress the protein in soluble form intracellularly in E. coli, purification is often achievable and convenient.

  • Otman Jai asked a question in Comsol:

    can COMSOL solves NEUTRONIC EQUATION. An example