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  • Michael P. Weinstein added an answer in Species Distribution Modeling:
    How can I predict the impact of salinity on fish habitat?

    I want to analyse the climate change impact on sea level rise and salinity intrusion of a river. After that I want to predict the impact of salinity on fish habitat. I have read many papers on which species distribution models are mentioned. Kindly suggest me some other techniques through which I can analyse the impact of salinity on fish habitat.

    Michael P. Weinstein

    Here's a couple more papers and citations therein.!

    + 1 more attachment

  • Jorge Morales Pedraza added an answer in Applied Mathematics:
    What means Dataset?

    I see information says "your peers X added a dataset", when I explore the content I find an article. Please what means dataset??

    Jorge Morales Pedraza

    Dataset is a collection of similar and related data for processing by computer. However,there are other definitions of dataset. In the field of Mahtematics, dataset provide an efficient and logical collection of data that can be easily accessed using AutoMate expressions. Using the Loop Dataset action makes traversing a dataset simple, while the use of expressions with specific column numbers makes accessing any row of a dataset a snap. 

    Another definition is dataset is a collection of data.

  • Hamidur Rahman added an answer in Hyperspectral Imaging:
    Is there any useful link where we can get Hyperspectral Image classification programs using Hyperspy?

    All Academicians,Scientists,Research Scholars...

    Hamidur Rahman

    Hopefully the following links can help you:

    About HyperSpy:


    other helpful links :




  • F. Leyvraz added an answer in Gravity:
    Can we design the orbit of a satellite with Einstein’s curved space?
    I think that the most successful theory of gravity is that the orbit of planet can be explained with this theory and the orbit of satellite was designed with this theory. To design an orbit of a satellite, the three of the factors of the orbit: 1) The radius, 2) The inclination angle, 3) The eccentricity, must be calculated. And, the Newtonian theory of gravity is the only theory that can calculate the three factors. In another words, if there was not the Newtonian theory of gravity, the orbit of the satellite could not be designed. It was known that, from Einstein’s field equation, the orbit of planet can be deduced. And it was used to explain the advance of the Mercury perihelion. But, I cannot find the method to calculate the three factors with Einstein’s field equation.
    F. Leyvraz

    ``It's not relevant who found that, but the flux explanation is valid in 95% of sciences (except perhaps in some weird theories). Gauss' flux is doing excellent work.''

    About 95 % of sciences I shall say nothing. No doubt the heat equation is excellent in describing heat propagation, and Laplace's equation is important there. But as far as ``explaining'' gravitation is concerned, I am not aware of any serious work providing an explicit link between Laplace's equation and the 1/r form of the gravitational potential. It is, of course, clear that 1/r *is* a solution of Laplace's equation, but I am not aware of anyone claiming a physical relationship between the two.

    Again, the first explanatory connection I am aware of is given by the low-speed limit of Einstein's equations: these then lead to motion in a potential which solves the Laplace equation with the density as a source term. Next order corrections lead to the 1/r^3 term, which is also essentially exact for geodesics in a Schwarzschild metric.

  • Carlos Araújo Queiroz added an answer in Thin Layers:
    How can I clean plexi-glass from PEO solidified thin layer?

    I used 0.5% PEO (Mv=300, 000) solution over a plexi-glass surface. On cooling it got stuck to the surface and is extremely difficult to remove. Can anyone suggest, how to clean the surface from the polymer.


    Carlos Araújo Queiroz

    A few solvents for PMMA ― therefore to be avoided while cleaning it ― can be found at: https://www.researchgate.net/post/With_PMMA_which_solvent_to_use

    About solvents for PEO you may want to check: https://www.researchgate.net/post/What_is_the_best_solvent_of_PEO

  • Akram Abdulameer Abbood Al-Khazzar added an answer in Photovoltaic Systems:
    PV vs CSP solar technologies?

    The energy demand has increased exponentially during the last decade and should reach 50 TWh in 2050. It is admitted that in the future, renewable energy sources should replace fossil fuels and reduce GHGs emissions which are responsible of climate change. The huge solar potential  is pushing investments toward CSP and PV technologies [1]. The two technologies are now in an open competition but PV is still leading with a comfortable ranking as a third source of Renewable energy. CSP technology still needs technical and economical improvement although it’s thermodynamically consistent.

    Akram Abdulameer Abbood Al-Khazzar


    here is my paper about auto cover the PV module at night time.

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: In spite of many advantages behind the dependence on the photovoltaic (PV) systems butthe efficiency level of the PV module still not satisfying. The fuel of the PV modules is the amount of sun light absorbedby the module and that depends on many factors such as front surface reflectivity, solar beam incidence angle and the most important is the transmissivity of the front surface. Soiling and dust accumulation reduce the transmissivity. This article presents a review for the studies about the impact of dust accumulation on solar PV module performance and a discussion for some solutions or cleaning techniques implemented in the previous studies. Also in this work, a new method is introduced to reduce the soiling. The method can briefly described as a moving cover with a cotton cloth attached firmly to the backside of the cover. At sunset, the module should be covered and the cloth wipes down part of the dust and the opposite happens at the sunrise. The results showed that a 9.22% gain in power produced by covered module than the uncovered module. Also, the covered module output was very close to the module after it was cleaned.
      Full-text · Article · Dec 2015
  • Peter Sjöblom added an answer in Fuzzy Control:
    control stepper motor rotation by time vs. step size?

    I would like to control the rotation of steeper motor versus time. First, I want to rotate the stepper motor (ccw) certain rotations versus time until reach certain step within certain time( each step has to complete within certain time). After that I want to rotate it to the start position (cw). Second,  stop it for certain time and then  repeat the first step, keep repeating first and second steps until certain time. finally,  rotate the stepper motor one complete rotation, and repeat this process. What kind of control is the best to use here? Could I use Fuzzy control? 

    Peter Sjöblom


    I agree with the above answers. The motion you describe is easily controlled by a stepper motor driver. A constant speed forward and then another constant speed backwards. Micro switches could be added to tell the controller when a position is reached if you want to add more security to your system. Also, a closed loop if a precise rotation over time is needed as a stepper motor could loose a step here and there if the load is to heavy.

    The motor and the driver of that motor you are looking for depends on the system you want to drive. A heavy system requires a big motor. If you are new to stepper motors I would like to suggest that you buy a Raspberry Pi and a stepper motor driver to it. There are several to choose between. One of them comes from Adafruit. With this inexpensive system you could build a prototype mimicing your final system.


  • Haroon Rashid added an answer in Dental Implants:
    Cements for dental implant crowns ?

    Dear fellows,

    What do you think is a better cement for crown cementation over implant abutments ? Is there anything ideal ? 

    Haroon Rashid

    Dear Roberto thanks. I agree that cad cam are precise but u actually cannot fully rely on retention and resistance form. I think zinc phosphates are quite strong for implants and ive felt that retrieval has been difficult. Thanks for your point of view

  • Bj Odusami asked a question in Forms:
    How can I prevent a standard stirred reactor from getting clogged at the bottom?

    The clogs are results of byproducts that form inside the reactor itself so they were never introduced at the influent but are often present at the effleunt.

  • Esa Säkkinen added an answer in Particle Physics:
    Graviton has not been observed sofar.but how does it have spin 2?

    According to Yukawa theory, long range force carrier particle have zero mass.but how does it have spin 2?

    Esa Säkkinen

    Anton: The "fermions" are the fields (=matter), the bosons make the "force".

    You think the mass indicates no matter?

    I think the matter field is the same as the gravity field and the fermion-like vacuum energy, maybe the same basis as behind the neutrinos, seems to be quite a good candidate to form that field.

    Besides, the gravity is no force.

  • Laura Elizabeth Pinto added an answer in Learning:
    What is the value / purpose of education without knowledge in the human life?

    Why some students and teachers get involved in malpractices?

    Laura Elizabeth Pinto

    Have you explored the literature on Holistic Learning? That might offer you a direction.

    Also, I'd strongly suggest reading Freire's work (especially Pedagogy of the Oppressed). 

  • Sunit Mitra asked a question in Ericaceae:
    Can any one may provide me the monographs on the genus Rhododendron of the family Ericaceae?

    Rhododendrons are one of the most beautiful flower producing genus of the family Ericaceae in India there are about 84 species of Rhododendron.  I want a recent taxonomic key and a detailed distribution of the members of this genus.

  • Laura Elizabeth Pinto added an answer in Collaborative Writing:
    What collaborative tools work best for small group work online?

    I am interested in research and experience about collaborative writing tools, research tools, tools that facilitate online teamwork, tools that enable students to do things like create a video together at a distance.  

    Laura Elizabeth Pinto

    For animated videos, PowToon's free interface is quite good. Also, YouTube has some video editing features that look useful, but I haven't tried them yet.

  • Sabeur Aridhi added an answer in Big Data:
    What is best tool for machine learning in big data?

    i want know what is best tool for machine learning in big data, i used MLLIB API in spark framework and i want test another tool.

    Sabeur Aridhi

    May be you can use Mahout.



  • Rafael Arcos-Ramos added an answer in Chalcones:
    Could anyone kindly let me know the regioselectivity in chalcone synthesis?

    I've synthesised chalcone from 2,4-dihydroxyacetophenone and p-anisic aldehyde in base condition (KOH/methanol). There are many problems,

    first, the products are cis-trans isomer, with ratio 2:1. What factors lead to regioselectivity in this reaction?

    second, the yields are less than 50%. How to increase the yield?

    and last, if i using montmorillonite (heterogen catalyst), does it impact on regioselectivity and impurity?

  • David Eugene Booth added an answer in SAS Programming:
    How do Combining ability and heterosis analysis of 4 males, 14 females and 56 crosses grown at 4 locations with two replications in RCBD design?

    Which program will be better for analysis of this data. I need help to analyse this data in SAS program or any other program. If any friend provide my example for data preparation and running in SAS program. 

    David Eugene Booth

    I would suggest looking at John Lawson, Design and Analysis of Experiments with R, CRC press pp 114ff. This includes examples with code. There is also a SAS version of this book. Best wishes

  • Peter McNamara added an answer in EMI:
    What methods and strategies are used today in dealing with the lack of sufficient English skills among teachers and students in EMI in universities?

    English Medium Instruction in Higher Education

    I am interested in situations when teachers and students are not native speakers of English

    Peter McNamara

    Hi Roman, This is a great question and one that is being actively addressed by management education researchers. The Management Education and Development (MED) division of the Academy of Management had a cacus about this topic last year, lead by Professor Dirk Moosmayer, University of Nottingham Business School. He might be a good person to ask this question to. Another suggestion is to send this question to all MED members via the Academy of Management MED listserv.

    Here is a list to the MED website, where the listserv amongst other resources can be found.

    I think you ought to get a good few relevant answers from that listserv (if you are an AOM member, then just access via the AOM listserv lists - you might also be able to do this as a non-member). Best of luck in getting answers to this question - it is one of the key ones for educators and students at this time. 

  • Aiman Shamim added an answer in Nanoparticle Synthesis:
    Why use reducing agents in nanoparticles synthesis?

    In nanoparticles synthesis, reducing agents change metal into its zero oxidation state,which form cluster with other atoms and then coated with capping agent, why necessary to change metal into zero oxidation states, which force responsible to form clusters?

    Aiman Shamim

    In case of carbon nano dots or carbon nanoparticles , there is no reducing agent snd there is no stabilizing agent ? how nanoparticles form there and how are these stabilized with out capping agent?

  • Vahid Hajiloo asked a question in Gene Bank:
    Hello there .... can any one report plant gene banks all over the world?

    i'm looking for Hyssopus officinalis ecotype.


  • Claus Tieber added an answer in Corruption:
    Was Serpico (1973) the first film that took the public denunciation of police corruption for its subject?

    While many films prior to the 1970s raised the issue of pervasive police corruption (The Big Heat, Touch of Evil…), I tend to think that Serpico was the first film that dealt with cops denouncing police corruption. Is there any film prior to Serpico that would talk about the exact same thing?

    Claus Tieber

    in the modern sense of film about "internal affairs" Serpico is one of the first, yes. Magnum Force came out the same year. In general corrupt cops can be seen in silent cinema and in the films of the first wave of ganster films in the early 1930s.

  • Laura Elizabeth Pinto added an answer in Critical Discourse Analysis:
    What are the teachers' perceptions of the magnitude of clerical/official workload assigned to them compared to their in-class teaching assignments?

    I need to write a research paper that employs Critical Discourse Analysis of tertiary level teachers' perceptions of the magnitude of official workload assigned to them rather than real classroom teaching assignments. I also need to get this data from online teachers' forums so that I may integrate efficacy of Web 2.0 in the research methodology.
    Any ideas ?

    Laura Elizabeth Pinto

    I would urge you to look at the literature on intensification of teachers' work, as well as some of the critical literature.

    A great start would be http://www.tandfonline.com/doi/abs/10.1080/0268093022000043065#.VrjnHfkrLIU

    Also, look at Ball, Maguire & Braun's (2012) book which explores UK teachers and policy. 

    Hope that helps!

  • Bernd Schmeikal added an answer in Operator Algebras:
    What is the relationship between lowering (raising) operators for identical particles from different sources?

    The principle of the Hanbury-Brown and Twiss experiment (see picture) says that the joint amplitude of probability that a particle from the source A be detected in the detector 1 and a particle from the source B in the detector 2, undergoes superposition with the joint amplitude of probability that a particle from A be detected in 2, and a particle from B in 1.

    I am not sure on a couple of things when we do operatorial treatment. 

    Let âA1 , âB1 , âA2 and âB2 , represent the raising operators that create a particle of type A at the position of the detector 1, a particle of type B at the position of the detector 1, and so on.

    If I construct the two-particle field operator (see picture)

    (1) Ȃ = |pA1> âA1  |pB2> âB2 + |pB1> âB1 |pA2> âA2 

    and calculate <Ȃ Ȃ>, one of the terms will be

    (2) <pB2|<pA1| x |pB1>|pA2> <âB2 âA1 âB1 âA2> .

    where by  x  I denoted direct product.

    From here on I feel confused. Which operator commutes with which? I suppose that âB1 should commute with âB2 because they act at different places. However, if the two sources are identical, âA1 and âB1 should not commute. And though, what I saw in some article is that the index of the detector is ignored, and the relation (1) is written as

    (1') Ȃ = |pA1> âA  |pB2> âB + |pB1> âB |pA2> âA

    Then the term in (2) becomes

    (2') <pB2|<pA1| x |pB1>|pA2> <âB âA âB âA> .

    Does somebody understand this?

  • Abdelhafid Nani added an answer in Free Radical Scavengers:
    How to calculate IC50 value of DPPH radical scavenging assay?

    If I follow this protocol: The antioxidant activity of the extracts was  tested using DPPH as previously described with some modifications (Zhang et al., 2011). Briefly, the DPPH free radical scavenging activity of grain extracts was determined using a 2 × 10−4 M DPPH solution. Each sample (0.5 ml) was mixed with 4 ml 2 × 10−4 M DPPH in ethanol. The mixture was shaken, and then left to stand for 60 min in the dark. The absorbance was measured at 517 nm in a spectrophotometer. The absorbance of the control was obtained by replacing the sample with 80% methanol. The DPPH radical scavenging activity of the sample was calculated as follows:

    % scavenged= [1- abs of sample/abs of control]x 100

    Abdelhafid Nani

    Dear Roy,

    For me, I use Origine software to determine IC50, by ploting, of variuos concentrations in a way the smallest should exeret an scavenging capacity less than 10%, and the highest more than 90 %. It is also easy and accurate.   

    Best regards! 

  • Lilliana Ramos-Collado added an answer in Visual Culture:
    Is public art "public"? Is it art? Who's its owner/its public? What does it mean? We need it? Who will preserve it? Can any such artwork be universal?

    With respect to “public art,” an examination of the state of the question points to at least two ways in which that concept may be defined, two “circles” within which it may fall: It may be related either to the space the art object is to occupy (which might be called a “public space”) or to the art object itself (which might then be called “public art”). Here, we might pose several questions that seem either to make it easier to understand the public art/ public space duality, or to make such an understanding impossible. We might, for example, ask questions about:

    Legitimacy (Is the work an art object?)  

    The constitution of the cultural imaginary with respect to what a “public space” is and what “public art” is (Does the work reflect my identity?)

    Ownership of the space and the work (Who owns what?)

    Authorship (Is the work created by an individual with personal title to it, or is it created on behalf of a collectivity?)

    Decency and decorum (Is the art appropriate to the space it occupies or will occupy, and is it suitable for being seen by men, women, and children?)

    Preservation and conservation (Who shall assume the ownership of the patrimonial work and be responsible for its explanation and esteem, defense, custody, maintenance, restoration, and permanence?)

    Each of these issues raises a debate, implicit in the very existence of the public-art object, and each debate may be different. And each potential controversy suggests its own “public,” in the sense of audience or interest group, each with its own defining expectations. Below a polemical article I wrote about a country-wide public art project:


    What is left of the project's website: http://www.artepublicopr.com/html_espanol/ambitos/1492_1898/portacoeli/fase3.htm#

    Lilliana Ramos-Collado

    Dear Juana María, I discuss graffiti in the article I posted underneath the question. If you have time, take a look at it. I am also very concerned about graffiti vis a vis public art, and the consequences of accepting or not accepting it as such. You have added a very important element: when the people decides by itself what it considers is "public art", graffiti being an excellent example. Thank you!!!!!

    Best regards, Lilliana

  • Ruchi Patel asked a question in Restriction Enzyme:
    I am doing DNA restriction enzyme digest on 7 kbp plasmid and I am trying to concentration of 0.32 mg/ml of 3618 bp?

    I do not know how much I can scale up the reaction volume. I tried with 9 ul of NdeI and 18 ul DNA in 300 ul and I got concentration of 0.15 ug/ul. How can I get my desired concentration?

    I need 300 ul of 0.32 mg/ml concentration

  • Salim salim Hamieh added an answer in Turbulence Modeling:
    Do we need to check the y+ values for SST K W turbulence model during post processing and if yes, should the y+ value be `1’ everywhere on the wall?

    In SST k omega model the flow is resolved up to the wall. For this the y+ =1. However, in some cases where the solution is converged and showing fairly good results, the y+ values are different. 

    Can this be treated as an acceptable solution?

    Salim salim Hamieh

    Yes for sure , as Franco mentioned the dimensionless wall Dis should be 1 and refine your mesh to about 500 to get higher data accuracy .

    Your simulating ?


  • Enrique Bernárdez added an answer in Interlinguistics:
    What languages share the same characteristics with Basque in case of numerals and nouns?

    In Basque when you say "five euros" you do not add the plural morpheme to the noun which follows the number, thus you say "bost euroØ" (i.e. five euro). In questions when you are asking the quantity, you do not need any plural marking either, e.g. "Zenbat etxeØ dago?" (i.e. "How many apple?"). I would like to know what languages share the same characteristics with Basque.

    Enrique Bernárdez

    Many languages do not use a plural form in nouns (or verbs etc) if there is a numeral present. An example is Quechua.

  • Jackson Achankunju added an answer in Photobioreactors:
    Any tips on how to harvest microalgae biomass from a small scale open pond?

    Hello researchers :)

    I am struggling with harvesting algae from a 150L open pond. I used to utilize a centrifuge for harvesting biomass when I cultured algae in 1L photobioreactors.

    Any advice how to harvest from small scale ponds?


    Jackson Achankunju

    Dear Zinedine,

    The harvesting method to be adopted  depends primarily on the type of algae(size  in particular).Three common techniques for harvesting algae are centrifugation, flocculation and  filtration.However we used a nylon cloth (of pore size around 30µm ) fitted in a  wooden frame for harvesting during our Spirulina - pilot project. 

    A couple of references :

    1. Harvesting marine algae for biodiesel feedstock,Dinh Trinh Thanh Xuan

    2. Algal biomass harvesting from the integrated algal ponding system (IAPS) for horticultural nutrient enrichment,M.P. Horan, S.J. Horan And P.D. Rose

    Good luck!

  • David L Morgan added an answer in SPSS:
    Is there a way to perform a partial correlation with nonparametric data and continuous variables in SPSS?

    Is there a way to perform a partial correlation with nonparametric data and continuous variables in SPSS?

    David L Morgan

    If the variable that is not normally distributed is skewed, you can try a logarithmic transformation to produce something closer to a normal distribution.

  • Sepehr Yousefdoost asked a question in Nanoencapsulation:
    Nanoencapsulation with alginate?

    Does anybody know an exact protocol to encapsulate of silymarin extract  with alginate?