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  • Pål Næverlid Sævik added an answer in Comsol:
    Does anyone know how to import a continuous variable (numerical function) from MATLAB to COMSOL without using txt file and interpolation?

    I am trying to solve a set of PDEs using a combination of MATLAB (to run the loop) and COMSOL. Then I use the output of COMSOL and after small process the output of COMSOL which is loaded in MATLAB should be imported again into COMSOL model to update first variables. It is easy to import data from COMSOL to MATLAB but it is difficult to do the reverse. I am looking for straight way to import data from MATLAB to COMSOL. I should mention it is possible to write the data in txt file and then import it by interpolation but I don’t need interpolation on the data and this seems to increase the total running time drastically. Does anybody have any suggestions?

    Thank you

    Pål Næverlid Sævik · University of Bergen

    There are several ways of combining Comsol with external software. In my experience, the best way of communication is through the Java interface. Calling Comsol from Matlab is also easy. It's possible to call Matlab functions from withing Comsol as well, but this is a hazzle.. 

    In my experience, using txt files and import by interpolation is the best way to go. But it depends on your problem. It would help with a more detailed explanation. What kind of data are you trying to import?

  • Sunil Prasad Lohani asked a question in Microbials:
    Biomass Mass Balance?

    If we use Monod Model as in Equation 1 to find process kinetics,

    rg = (u_max*S /(Ks+S))*X–kd*X ...................................................(1)

    rg = net rate of biomass production, gVSS/m3.d
    Ks: Substrate concentration at one half the maximum specific substrate utilization rate, g/m3
    Kd: microbial decay rate, gVSS/gVSS .d

    Where we know except, Ks and Kd, Now, How can we calculate Ks and Kd. Do you have any idea?

  • Firdos Jahan added an answer in Chitosan:
    What are the alternating horizontal lines in my my pure chitosan SEM image?

    Please help me out. I am unable to understand this image. I have prepared pure chitosan by adding 5g chitosan powder into 500mL acetic acid

    Firdos Jahan · Gulbarga University

    i want to remove dat film from petridish easily...how can i remove dis easily? what will be the best method?

  • Vivek Morya added an answer in ImageJ:
    How to quantify the protein band at SDS PAGE ?

    any one familiar with   imagej program to quantify the protein band?

    Vivek Morya · Inha University

    I used Alphaimager Gel Doc system for the same, following links will help you ...





  • Ouerdachi Lahbassi added an answer in MODFLOW:
    Which software is more appropriate to use for groundwater and contaminant transport simulation, ArcGIS or Visual MODFLOW Classic Interface?

    Dear all,

    I am doing my final year undergraduate degree project based on "Assessment of groundwater vulnerability to contamination in the vicinity of a landfill in Mauritius".  I am planning to develop numerical model for groundwater flow and contaminant transport in order to carry out predictive simulations for advective-dispersive transport of leachate within the subsurface.

    Can you advise me on which software is suitable between ArcGIS and Visual MODFLOW Classic for this purpose?

    Also, the landfill is characterised by a double liner system made of clay and geosynthetics.  From technical journals, it has been acknowledged that these liners deteriorate with time.  Is it worthwhile to carry out this groundwater vulnerability assessment?  Can you provide me with your views on this type of assessment?

    Thank you.

    Ouerdachi Lahbassi · Badji Mokhtar - Annaba University

    For a subsurface dam study, we combined Arcgis, MODFLOW and COMSOL. Attached: Article link


  • Joachim Pimiskern added an answer in Mathematics:
    What is number? Why and how does it come, how does it exist, how many number forms do we have so far?

    No mathematics without numbers; so, we have many different kinds of number forms in our mathematics to cognize all kinds of things in universe.

  • Nils Goerke added an answer in Patterns:
    How can we make clusters and compare for attributes with unequal samples?

    If we make clusters for patterns but each pattern was not equal in numbers of position in playground because the time for each one is different so sometimes. we have 200 position in coordinates x and y and some others we have only 150

    Sport neural network

    Nils Goerke · University of Bonn

    Dear Amr Abdulfattah Hassan

    in case your data is not uniform, you can try to "fill in " the missing data using assumptions acquired from experience, theory or by statistical methods (see answer from  Ashish Dutt)

    Another method is to extract features from the original data sets and perform the clustering using these features. Typically these features are chosen, or constructed in such a way, that they are invariant with respect to some aspects. e.g. rotational invariance, or scaling invariance or ...

    For your specific case it would be necessary to choose features that are invariant with respect to the number of values in each pattern.

    Sínce i do not know the application you have in mind, and thus i do not know what these patterns are representing, it is a bit difficult to propose features.

    See the method of Bag Of Words , or Bag of Visual Words.

    A nice introduction can be found:

  • How does the seeding mechanism in single crystal formation works?

    An explanation is sought from the view of interatomic forces and interactions between seed crystal and the molten target material.

  • Can you any body suggest, which electrode is suitable to remove fluoride from water from elelctrochemical method ?

    One of the major challenges facing mankind today is to provide clean water to a vast majority of the population around the world. Development of cost effective and simple technology is very much essential to purify water obtained from natural sources.

    Prakash Kariyajjanavar · Gulbarga University

    Thank you for your suggestion  Dr. Julio Cesar Bastos Fernandes

  • Sachin Kumar Sengar asked a question in ENVI:
    What is the procedure of applying PCA on SAR images using ENVI 4.8 software?

    how to apply principal component analysis on synthetic aperture radar images?

  • What are the ways to hold the prestress in the reinforcement in ABAQUS?

    I am modeling a prestressed concrete beam using the Concrete Damaged plasticity model. I am using the values from the verification manual. For the reinforcement i used the wire element and use the embedded region constraint to define the bond. I introduced the prestressing using the predefined field. I am able to run the model but failed to capture the initial load-deflection behavior of the prestressed beam. I guess it has something to do with the initial rebar stress. I am using a 2D model. Can anyone suggest a method/step to analyse a prestressed beam (2D or 3D) using ABAQUS? Example would be highly appreciated. Thanks!

    Nancy Debora · Karunya University

    how to use the initial condition and prestress hold option in abaqus

  • Abhay Mishra added an answer in Phytochemistry:
    Can anyone suggest how I can crystallize the compounds from pet. ether fractions collected by CC?
    I run a column of pet. ether extract and collected 25 fractions from pet.ether: ethyl acetate (80:20) mobile phase. One fraction showed single spot on TLC in same solvent system but difficult to get it as in crystal form. when i concentrate it in reduced pressure it forms green color sticky mass. Can anyone suggest how I can separate it as pure and crystallize form?
    Abhay Mishra · Hemwati Nandan Bahuguna Garhwal University

    Respected Jacobus Nicolaas Eloff Sir, I applied your suggestion to crystallize compound from pet ether fraction. When i add warm sol. of Acetone to the fraction, get turbid solution then keep it to cool. After 48 hrs i saw the fraction then i found there is white color precipitate with some impurities at the bottom of the soln. Can you suggest me again what i do next? Is that precipitate may be a compound. Could i do any test for confirming that.????? 

  • How do I assess nitrogen availability in dryland soils?

    In wet, northern hemispheric soils, there is a strong body of work which suggests that the quantification of soluble N in pore water (or soil solution) is the most appropriate method of assessing point-in-time N availability via lysimeters, rhizon samplers, or centrifugal extraction. More recently, Erich Inselbacher's microdialysis methods also looks promising.

    However, in dry soils (such as those covering Australia, my study area, for much of the time) extraction of pore water is impossible. Traditional salt extracts (KCl / K2SO4) probably don't give that accurate a picture of what was actually plant/microbe available, and significant changes in analyte chemistry have been observed over the duration of a water extract. Also, extracts totally lose any effect of soil structure on what is extracted.

    So, are there any other methods that may be more analogous to pore water extraction than KCl extracts, but are suitable for dry soils?

    Selva Selvarajah · Enviroknowledge Ltd, New Zealand

    Whether wet or dry zone I think that the hunt for a suitable method to assess available N is still ongoing. Monitoring mineral-N in pore water may not necessarily indicate the extent of N availability in wet areas. Sometimes assessing potentially available N (or mineralisable-N) by incubation may be helpful (e.g. 7 day anaerobically mineralisable-N @400C). Please see my publication (Technical Report: An evaluation of some laboratory methods of assessing availability of nitrogen in agricultural soils) on this area.

  • Rana Zareef asked a question in Urine:
    Does bacteria normally present in urine?

    does the urine of healthy person normally present bacteria?

    and what is the normal average of bacteria in urine?

  • Michael Moecker asked a question in Papers:
    Is there empirical support for assuming constant absolute risk aversion (CARA)?

    At the moment I am trying to judge the validity of a model assuming a CARA-Utility-Function. And I vaguely remember that experimental results usually suggest decreasing absolute risk aversion.

    Unfortunately I cannot find any literature on estimations of risk-aversion and its behavior when stakes get higher at all.

    Are there papers like this?

    Thanks for your help!


  • Chetan Arya added an answer in Shoulder:
    Excited my protein at 383nm and got emission at 450nm. What information/s can I get from there?

    My protein has color of brown but in UV_Vis spectroscopy no distinct band after 280nm. At high conc. of protein I can observe at shoulder at 383nm so I excited my protein sample at 383nm and took emission spectra where I got the 450nm emission. I dont know what causing color to my protein and also dont know the interpretation of fluorescence spectra. Can any expert help me?

    Chetan Arya · Indian Institute of Technology Kanpur

    Cant do the native as acrylamide is one of the substrate but sds-page give clean bands after gel-purification.

  • Md Samsuzzaman Sobuz asked a question in HFSS:
    Is there any one who have done CPW antenna in HFSS . I need to know about port and radiation box size?

    Is there any one who have done CPW antenna in HFSS . I need to know about port and radiation box size?

  • Which is best book on behavioral psychology ( all parameters included) of females.?

    Any person with Psychological and Sociological background with specialization on Gender and Behavioral study

  • Firdos Jahan added an answer in Chitosan:
    What are the alternate horizontal lines from my pure chitosan SEM image I am getting instead of a plane image?

    plz help me out i am unable to understand this image..i have preparedpure chitosan by adding 5gm chitosan powder into 500ml acetic acid

    Firdos Jahan · Gulbarga University

    dear crowly and vladimir thnq for ur vlubl sugstn...i vl go for higher magnification and lower voltage frst and den i vl see it..how it came.

  • Muhammad Sarwar asked a question in Crop Physiology:
    H202,salicylic acid and hydrogen peroxide and potassium, zinc boron helps to reduce ethylene production?

    Botany, plant and crop physiology, soil science, agronomy

  • Chetan Arya added an answer in Plasmids:
    Which plasmid can I use for plasmidic DNA damage in the presence of metallic complexes ?

    Hello everyone, I'll have make some tests of DNA degradation (plasmid DNA)  with some metal complex. In several articles, I read that this kind of test was done with a plasmid call pUC19. I wanted to know, can I use an other plasmids (for example the pET plasmid ) or I have to use this to force ??

    Thanks a lot


    Chetan Arya · Indian Institute of Technology Kanpur

    You can try pBR322 and pET21/19/28 for the studies. these plasmids varies in length but gives a clean result of experiments. also these are easy-to-get.

  • Nancy Treneman added an answer in Estuaries:
    Does anyone have any information on this bryozoan?

    I found a bryozoan on wooden docks at Ilwaco, Washington State, USA, which is rather unusual. It has bilaminar erect, flexible fronds. There is no gymnocyst, the cryptocyst is smooth, and the mural rim has fine serrations. There are 2-3 mural pores. and sieve plates between the zooids. It is a rather beige brown color, looking a bit like snake skin.   It was very abundant, looking like a pile of leaves. We have a tentative identification of Membranipora lingdingensis, a species from coastal estuaries in China. Does anyone have any knowledge of this species, and know what vectors might have brought it to the Pacific Coast of North America? 

    Nancy Treneman · University of Oregon

    Hello Et al:

    Here are some amazing SEM's of this specimen taken by Matthew H. Dick at Hokkaido University. Hopefully they will answer some of your questions and help with determining its identity.  Several people have looked over these photos, and suggested it is similar to Membranipora chesapeakensis, (Conopeum). 


  • How can we draw hydrogen bond in material stdio?

    i am blending two polymer and in that hydrogen bonding interaction is there. i am unable to make it in material stdio so what should i do.

    Ali Ibrahim Al-Mosawi · Free Consultation



  • Tayebwa Dickson asked a question in Beef Cattle:
    What is the standard biomaker for stress in beef cattle?

    i want to know what biomakers of stress have a direct influence on the quality of beef produced

  • Prakash Kariyajjanavar asked a question in Fluoride:
    Can any one suggest me... that Is there any possible to remove fluoride from water using carbon as an electrode...?

    I want use Carbon as an electrode to remove fluoride from water ... I have little confusion with this .....

  • How do you teach meaning in foreign/second language acquisition?

    Some teachers of English,and me too, follow the Modern Language Association Report of 2007 which promotes teaching meaning by the use of various methods and disciplines of knowledge.

    harikrishna rao Sampatarao · GMR Institute of Technology

    Dear colleagues,

    It is my opinion that the meaning of a word should be explained in context(as Mr. Klaus suggested) or with collocations rather than directly giving the other equivalent word or a translation. sometimes it may be effective that asking the learner to guess the meaning of the new word in relation to the rest of the words in the sentence or providing another sequel sentence with the same word. A mind mapping technique often solves the problem if these methods wont work out, the recourse is providing a mother-tongue equivalent.

  • Does anyone have experience on identification of fisheries sensitive watersheds for prioritization?

    Suggest approaches, techniques, indices, etc. and available research and publications/online resources to help characterize watersheds based on fisheries interests vis-a-vis watershed features for conservation and development.

    Muruganandam Muthiah · Indian Council of Agricultural Research

    Training of prospective youth from the region to get basic know how on principles and practices of integrated fish farming would help mobilize farmers towards adoption of improved fish farming and conservation of fisheries resources in areas where people's participation seems to be poor.

    We may organize people and explain them the benefits and positive impacts of fish, fish farming and aquatic ecosystems to environmental rehabilitation, food production and livelihoods. Importance of water resources for food production including fish foods with finer details need to be passed on to the villagers for their analysis and interpretation.

    Also, get interested individual farmers into confidence and give them complete support of inputs and fish farming techniques towards assured production at their instances. Upon seeing the success of such innovative farmers, others may come forward to use potential community water resources or structures that are lying unused for fish farming.

    Invariably, the thrusts for watershed-based fisheries development would include all these activities.

  • What is the difference between intermetallics and solid solution alloys?

    What is the difference between intermetallics and solid solution alloys?

    Sornadurai Dharmadoss · Indira Gandhi Centre for Atomic Research

    Dear Cláudio Geraldo Schön

    The question is not about the phase transition or order of phase transition, it is only about the difference between the solid solution and intermetallic compounds. 

    Please understand the question and answer it. 

    Any how  I could understand that you are familiar with  order of phase transition..

  • Muhammad Sarwar asked a question in Agronomy:
    H202,salicylic acid and hydrogen peroxide, these three could be called as growth regulators and in ASA foliar spray why CAT, SOD less produce?

    Botany, crop and plant physiology, Agronomy