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  • Nirmal Kumar Mahapatra added an answer in MATLAB:
    Have you any information about good books to know MATLAB theory and practice. PL cooperate ?

    I need information about good books to know MATLAB theory and practice. PL cooperate with me. Are there any internet links that may also useful ?

    Nirmal Kumar Mahapatra

    many many thanks to you, dear friend Salim.

  • Prasad Joshi asked a question in PSIM:
    How to design feedback control loop for intreleaved fly-back converter in PSIM ???

    Respected researchers,

    I'm implementing interleaved fly-back converter to boost DC voltage of microgrid, wherein it is desired to have fixed output voltage for any value of input DC voltage.

    I'm trying to implement the same in PSIM software.

    Please suggest the relevant solution/method.

    Thanks a lot.

  • Mohamed El Naschie asked a question:
    In simplistic terms Banach tarski theorem means we can get something from nothing ,is it not?

    if true then nothing is  a source not only of Einstein equations but also for every thing. This is in perfect agreement with set thory

  • Jochen Wilhelm added an answer in Z-Test:
    T-test or Z-test? I have two sets of data each over 100 cases. What is the right tool to test whether there is significant difference between the two?

    The size is over 30, but I am not comparing a sample and a population. Thank you.

    Jochen Wilhelm

    Two sets, each with n>100 -> at least 200-2 = 198 degrees of freedom.

    (1-0.05/2)-quantile of the z-distribution: 1.959964
    (1-0.05/2)-quantile of the t-distribution: 1.972017 (198 d.f.)

    The CI based on the t-distribution would thus be 0.6% larger. I still think that this is absolutely negligible.

    Explanation: Assuming that you know the SD does not add much relevant information if there is enough data for a good estimate of the SD from the data.

  • Edgar Owiti asked a question in Metamaterials:
    How do you obtain a slab metamaterial after calculating the required parameters from the unit cell?

    In many papers, after the required permeability and permittivity have been calculated from the unit cell the metamaterial structure is developed as a patterned structure of the unit cell, mainly guided by the TO. However patterning unit cells may not be possible or easy for all designs, so,  is it possible to obtain a slab with the same permeability and permittivity values that will probably make fabrication process less complex?

  • James R Knaub added an answer in Regression:
    In order to estimate the parameters of regression line (Bo, B1) for example, do we minimize sum square of residuals or sum square of errors and why?

    sum of e or   sum of u2. I mean e for sample and u for population. 

    James R Knaub

    I did look at your attachment before answering, and that was.the best I could make of it. 

    Also, note that n came up in both derivations, not N the first time, and n the next.  That seems to indictate the second derivation is the way to go.  But I have to say that I am not very good with notation, but I still think you want the "sample" approach notation here. 

  • Olatunji Oladimeji Ojo added an answer in Sheet Metal:
    What are the available techniques of removing cladding materials from metal sheet' surfaces?

    Apart from machining technique, is there any other method through which cladding material can be removed from the surface of metal sheets?

    Olatunji Oladimeji Ojo

    Thanks for your suggestions

  • Vijay Kumar Sarabu asked a question in CSR:
    Can any one provide me recent data on Corporate Sector Responsibility in India?

    Provide me Recent data on CSR in India?

  • Arnab Paul added an answer in Pulmonary Embolism:
    What is the most reliable marker in the differential diagnosis of pulmonary embolism and community-acquired pneumonia?

    Because of similar clinical manifestations and laboratory findings, differential diagnosis of pulmonary embolism and community-acquired pneumonia (CAP) is generally difficult. 

    Arnab Paul

    D- dimer, CT Angiography, Clinical Findings

  • Barbara Sawicka added an answer in Rice:
    What’s all the hype about “Gluten Free” foods? Sorting through the false claims.

    Just as fat was derided in the 1990s (saturated fat still is, depending which “authority” you speak to), and certain carbs were then rejected more recently ― today’s scornful attention seems to be directed towards gluten, a protein found in wheat, barley and rye. To be proclaimed “gluten-free” seems to be the new nutritional seal of approval.
    Not that there isn’t a place for “gluten-free” foods, but that place usually resides with people who have celiac disease ― an autoimmune condition in which gluten can cause potentially severe intestinal damage, or people who have gluten sensitivity. If celiac disease is suspected there is a blood test to check for antibodies associated with this ailment. In the event that this blood test is positive, a tissue biopsy of the small intestine is taken by endoscopy. Otherwise, gluten sensitivity or celiac disease can also be mistaken for other conditions, such as irritable bowel syndrome.
    Yet according to the National Foundation for Celiac Awareness, only an estimated 1 in 133 Americans, or about 1% of the population, has celiac disease ― although gluten- sensitivity may affect 6% to 7% of that same population overall.
    Nevertheless, the majority of consumers that follow a gluten-free diet are certain that it will improve their physical or mental health and gluten has been blamed for everything from joint pain to weight gain to forgetfulness. For these precarious reasons, approximately a third of consumers look for gluten-free products or try to avoid anything resembling gluten in others. They claim that with these products they have better digestion and gastrointestinal function, increased energy………that it lowers cholesterol and their immune system benefits. They also claim that going gluten-free even leads to healthful weight loss.
    But there is limited research to support any of these sentiments and by and large, with the exception of those who have celiac disease or gluten sensitivity, there is no clear medical reason to eliminate foods with important nutritional value such as rye, barley and wheat from your diet. In fact gluten might be good for you, as there is some evidence that it has beneficial effects on both triglycerides and maintaining a healthful blood pressure.
    Gluten-free foods can be quite bland, so while eliminating glutens from certain foods manufacturers add other ingredients, many of which only increase the calories, fat and sodium into your diet ― for which you pay approximately twice the price. Keep in mind as well, that a recent European Journal of Clinical Nutrition study found that around 5% of foods certified gluten-free didn’t even meet FDA standards for being truly gluten-free.
    Although approximately a quarter of the population perceives that gluten-free foods have more minerals and vitamins, some dietitians warn that the opposite is true ― that if you go completely gluten-free without nutritional guidance that you can develop nutritional deficiencies quickly. For example, whereas many gluten-free foods lack supplemental folic acid and iron ― products with wheat have them as additives. Moreover rice or rice flour is often substituted for the wheat, barley and rye in gluten-free foods and if the outer hull of the rice is removed this can lead to a deficiency in Vitamin B1, the progenitor for the disease Beri-Beri (Thiamine deficiency). As if this was not enough, a little known fact is that many of the kinds of rice or rice powder which replace gluten have been found to contain various degrees of arsenic in them. This is not to say that you cannot obtain gluten-free products without rice, but the majority of them have rice.
    Gluten-free foods actually seem to have a tendency to increase calories and the very risk of being overweight or obese that a third of their purchasers believe they are going to lose weight with. There is no evidence that stopping gluten gets rid of a belly – so if there is weight loss with a gluten-free diet, its most likely due to added motivation on the part of those pursuing such a diet, cutting starchy foods, or perhaps eating less and substituting fruits and vegetables for gluten containing products.
    So, in conclusion, there is much to think about before joining what is currently the largest and hottest trend in the food world ― going gluten-free.

  • Sujoy Sarkar added an answer in 2D & 3D:
    A sample composed of a film homogeneously mineralized with HAp, what type of nanomaterial could be considered? as a 0D, 2D or 3D ?

    I'm reading about mineralization with SBF in different kind of films, but i'm not sure if the resulting material ( an homogeneously HAp mineralized film) could be a 0D, 1, 2 or 3 dimension material. Thank you!

    Sujoy Sarkar

    Check the attached image.

  • Prasad Joshi added an answer in Electrical Power Engineering:
    Can someone suggest research topics for me in Electrical Power Engineering?

    I am considering starting a PHD program but my problem is getting a suitable topic. I need suggestions so that i can easily make my decision. Many thanks

    Prasad Joshi

    Interconnection of microgrids and utility grid at distribution level, implementing bi-directional power flow

  • Medhat Maaty added an answer in Fingers:
    From the orthopedic view does anyone know what are the causes of pain in fingers after wearing rings ?

    patients presented with severe pain in their fingers after wearing rings of different metals for along period .the pain increased with movement . no allergy from metals. the joint movement is restricted slightly.

    Medhat Maaty

    thank you Dr,Dietrich Klueber 

  • Gregorius Harvianto added an answer in Aspen Plus:
    Does anyone know the suitable parameters that need to regress in Aspen Plus? And what is the different?

    Regarding the Aspen Data Regression in Aspen Plus for LLE and VLE, we have two main binary interaction parameters aij and bij (referred to as elements number 1 and 2).

    We would like to know the different between those two parameters, since from the published literature we found that several researchers only regress to get bij, and others regress the experimental data to get both aij and bij parameters.

    Thank you.

    Gregorius Harvianto

    Thank you for your answer Mr. Sajad. 

    I understand it well.
    Furthermore, I just curious why some researcher only regress bij and the aij was set to zero, and others regress the both aij-bij parameters. Is there any special reason for this?

    As well as, I found in Aspen Plus. Aspen Plus also regress and provide the binary parameters for LLE and VLE in term of only bij or both aij-bij parameters.

  • Lakhvir Singh added an answer in Knowledge Representation:
    Do you have an experience in working with Knowledge Representation Tools?

    What is your opinion on applying Knowledge Representation tool to manage large documents and display them to user on request. Is there any tool which has this functionlaity with inbuilt reasoning algorithm/function?

    I am looking for a tool to manage large documents with a built-in reasoning functionality. It should be able to read office documents e.g. word, powerpoint etc from database and display them to the user.

    Lakhvir Singh

    @Hind, Thanks for your answer. IsTerreGov  an open source system or is it restricted for project partners?

  • Mahdi Safarpour added an answer in Conjoint Analysis:
    Is there any manual available for doing conjoint analysis through SPSS?

    Any material will be great help.

    Mahdi Safarpour

    Please check the attached files. They might be helpful to find your answers.

    + 1 more attachment

  • Vijay Kumar Sarabu asked a question in CSR:
    Can any one provide me recent data on Corporate Sector Responsibility in India?

    Recent data on CSR in India

  • Alireza Nik Sejel added an answer in Cognitive Science and Artificial Thinking:
    How i can modify weight of each input indicator and bias in ANN?

    hi guys i'm here with another question about ANN!! hope so to receive some cool answer from you...

    as we know, in ANN we can modify the amount of weights and bias. you will bless me if tell me how i can do this from advanced script.

    thank you

    Alireza Nik Sejel

    thank you dear Ebenezer

    i will try them.

  • Baazouzi Messaoud added an answer in Masonry:
    How can I calculate normal and shear stiffness of an interface element for mortar interface and internal brick interface?

    To define mortar interface and brick crack interface during modeling of masonry, i need normal and shear stiffness (Kn and Kt). I found relationship to calculate these values attached here for mortar interface. But in my case Eu < Ej. So how can i calculate? And how can we estimate clay brick normal and shear stiffness to define brick crack at middle of the brick?  I am using DIANA for it. Please suggest me.

    Baazouzi Messaoud

    dear sir

    Kn=Ks=max(K+(4/3)G)/ Z min)

    best regards

  • Sabin Basi added an answer in Rice:
    Could you please send list of references of rice work in Nepal for rice compendium in Nepal?

    Dilla Ram Bhadari, Program Director, Crop Development Directorate has initiated to develop a rice compendium of Nepal. On behalf of the Program Director, I would like to request you all to send list of references (full citation) that you or your colleagues have published. References should be related to rice works in Nepal as well as rice germplasm from Nepal. We are looking for any types of publications that say something about rice in Nepal. Also include references that you know even if you have not authored. We are also expecting abstract/ summary if possible of each publication. It is also requested to circulate it to others. These list of references will be made available to the team members of this venture which help greatly in developing rice compendium of Nepal.

    Send at joshibalak@yahoo.com or cddnepal2013@gmail.com

    Sabin Basi

    Please check one of our article on rice of Nepal if that is relevant for you.


    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: The present study was conducted to understand the effects of different doses of radiations by gamma rays of Co60 on cytogenetics of indica rice, Radha-4 at the Central Lab, Institute of Agriculture and Animal Science, Rampur, Nepal. The immature PMC of M1 generation plants were analyzed performing the usual smearing and squashing technique. Radiation had a significant effect causing different types of cytogenetic aberrations, such as univalent and multivalent association of chromosomes, chromatin-bridges, laggards, fragments, stickiness, and multinucleated cells. An increasing number of aberrant cells with increasing dose of radiation was identified. The greatest share of aberration was identified due to multivalent association as a result of translocation followed by bridges and laggards, and the least effect for the stickiness of the chromosomes. Finally, 35 KR doses of gamma rays was the most potent dose inducing cytogenetic aberrations in meiotic pollen mother cell of rice compared to other dose spectrum.
  • Ali Rahmani asked a question in Mixers:
    How I can calculate mixing index in micro mixers-experimentally and numerically through simulation-?

    how I can calculate mixing index in micro mixers(experimentally and numerically through simulation)?

  • Stam Nicolis added an answer in Gravitational Field:
    Is the non locality of the gravitational field energy a serious problem for General Relativity (GRT)?



    "Although there is no room for such a thing in the energy–

    momentum tensor T, it is clear that there are situations where a ‘disembodied’

    gravitational energy is actually playing a physical role.

    Imagine  two massive bodies (planets, say). If they are close together (and we can

    suppose that they are instantaneously at rest relative to each other), then

    there will be a (negative) gravitational potential energy contribution which

    makes the total energy, and therefore the total mass, smaller than it would

    be if they are far apart.  Ignoring much tinier energy effects,

    such as distortions of each body’s shape due to the gravitational tidal field

    of the other, we see that the total contributions from the actual energy–

    momentum tensor T will be the same whether the two bodies are close

    together or far apart. Yet, the total mass/energy will differ in the two cases,

    and this difference would be attributed to the energy in the gravitational

    field itself (in fact a negative contribution, that is more sizeable when the

    bodies are close than when they are far apart)." 


    The same problem was also rised by Thirring, Kalman and Feynman in the FGT theory, they inserted the gravitational energy in the tensor equations...

    It is a problem of paramount importance which prevents the General relativity theory from describing any motion in which the hamiltonian is time dependent or rather in case of non isolated systems, or in case of non stationary interactions between different bodies.

    The attempt to model a free falling body in a gravitational field for GRT seems impossible.

    GRT has been tested  only for static or stationary systems where there is not a net exchange of energy (excluding gravitational radiation)

    Don't we need another GRAVITATIONAL THEORY which includes the results give by GRT in order to explain with a better accuracy the simple phenomenon like the free falling of a mass in a gravitational field?

    Stam Nicolis

    Two systems are inertial if and only if they can be related by a Galilean transformation in Newtonian mechanics, by a Lorentz transformation in relativistic mechanics-the terms are synonymous. The only quantities that can be compared are the invariants of the transformations. In Galilean mechanics the time coordinate is such an invariant, spatial coordinates are not; in relativistic mechanics no coordinate is an invariant. (It doesn't make sense to ``exchange'' the position coordinate between two systems in Newtonian mechanics-it's not invariant under Galilean transformations. ) However there do exist other invariants. These are the only quantities that can be ``exchanged'', to check that the systems are equivalent, or not. And invariants that are consistent with interactions do exist-in Newtonian mechanics and relativistic mechanics, for example certain combinations of the total energy and the total momentum. So it doesn't matter how the coordinates are set up-if the invariants, computed locally,  are the same the two systems are equivalent, if not, they're not. That the invariants do have the same values is the statement that means ``the coordinates have been set up equivalently''. And there are  infinitely *many* choices that lead to the same invariants, not one.  However it doesn't make sense to compare quantities that are not invariant, since the coincidence that they take the same values isn't physical, else they would have been invariants.

    The content is that there exist invariant quantities and non-invariant quantities under such transformations. Much of the popular accounts stress the non-invariant quantities. That's wrong and confuses many people.

  • Kenneth M Towe added an answer in Global Change:
    Are there good quantitative parameters that characterize the degree of instability of climate or weather?

    There is a lot of attention to the trends of changing climate. Instability is also an important thing.

    Key words: global change, man-made impact, climate change, global warming, environment,

  • Duncan Cromarty asked a question in Plasma:
    When reporting drug accumulation and subsequent elimination in different organs, what are the correct terms to be used? Cannot be Cmax, Tmax and AUC?

    The Cmax, Tmax, elimination rate constant and area under the curve are PK parameters essentially reserved for describing the plasma or central compartment concentration changes, so how would the drug or metabolite accumulation and subsequent elimination which often follows the same trend as the plasma but at different concentrations and time lines be reported? 

  • Kazuharu Ohashi added an answer in Pollination Biology:
    What's the standard level of % seed set for self-incompatible, animal-pollinated flowers in natural conditions?

    I am looking for information on how much % seed set is the “standard” level for self-incompatible plants in natural conditions. Does anyone know useful references or compiled data sets etc. from which I can derive a quick answer to this?

    Kazuharu Ohashi

    Thanks Renate!

  • Shafagat Mahmudova added an answer in MATLAB:
    Can anybody know Matlab codes for optimal placement of DG ?

     I am one of new Matlab user . My Objective Function is to reduce the reactive power loss(refer to attachment ) .

    I got a code for simple objective function val = (x - 15)^2 + (y - 20)^2 , I run this and observe the results  and now i am quite familiar with PSO working on matlab . But 

    My objective is quite complex so please share program for reactive power loss minimization if any one have. Similar program will also help me in this regards 

    Shafagat Mahmudova

    Dear Syed Arif Rizvi,

    look the link. May be useful.


    Regards, Shafagat

  • Hessam Pakravan asked a question in Joint Instability:
    Would anybody brief me who else working in Numerical plate buckling?

    Would anybody brief me who else working in Numerical plate buckling?

  • Finn Årup Nielsen added an answer in Zero:
    Do you know how i can get inverse of a matrix that its determinant is zero or very near to zero?

    i model a shell in fortran code,and i calculate normal vector and deformation gradiant for it,but somewhere in the solution the z-direction of normal vector become so small and it cuase the determinant of defo-gradiant become so small and near zero and for inverse of it the element become so big and cause a problem,i want a way to avoid this

    Finn Årup Nielsen

    Pseudoinverse or singular value decomposition. I am not familiar with Fortran or LAPACK to recommend a specific function.

  • Arman Rezayati asked a question in Modeling:
    Does anyone know any good reference that comparisons data-driven and non-data modeling?

    Does anyone know any good reference that comparisons data-driven and non-data modeling?

  • Dudekula Gireesh asked a question in Adaptive Filtering:
    What are the causes of impulsive noise in a system ? What are the consequences ?

    I am implementing adaptive filter to remove impulsive noise in industrial plants.