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  • Ebrahim Ahamadi asked a question in Vibration Testing:
    Wath is Block Vibration Test (BVT) and how can i get some information about BVT?

    This test is conducted in Geotechnical in-situe tests as an indicator of dynamic properties of soil.

  • Marius Murariu added an answer in Fiber:
    What is the basis for characterizing fiber to be 'short fiber' in composite materials?

    I am looking for fiber size range that qualifies to be called as short fiber (away from being particle on one end and long fiber on the other) in composite materials. Since the glass-fiber reinforced ABS component being thin in size (about 3 mm) I would like to limit the fiber size.

    Marius Murariu

    Dear Srinivasa,

    If your question is remaining in actuality, just I saw the information about "The Long and Short of It: VLF (Very Long Fiber)" webinar — available following RTP Company site:


    To have access, you need to give some general information about your interest.

    With my best regards,


    PS: See you also




    + 1 more attachment

  • Bamidele Segun Donald Odeyemi added an answer in Mathematics Education:
    Are there any examples of incentives for upper secondary students to study mathematics?


    In Ireland, students are awarded bonus points for achieving a passing grade or better in the Higher Level mathematics Leaving Certificate examinations (upper secondary final exams taken at age 17-18). These bonus points can help them gain access to their desired university course. I'm looking at the effects of the introduction of this measure and wondered whether any other countries have similar incentives.  Any examples broadly related would be welcome, thank you.

    Bamidele Segun Donald Odeyemi

    The best incentive i think a child needs for a good academic performance is in the conduciveness of the child's learning environment, the child's ambition and most importantly developing a goal achievement that can enhance the child's performance; the goal achievement is centered around what a child intends to achieve in life academically, there is mastery orientation goal and performance orientation goal, all geared towards better performance in mathematics when a child has identified his goal orientation according to Nichole, 1984.

  • Yulia B. Peeva added an answer in Orthodontics:
    Anyone familiar with motivation and awareness in orthodontics?

    I should discuss basic health strategies for promotion and awareness of children and parents in orthodontic treatment. I'll be very thankful for your attention.

    Yulia B. Peeva


    This article is very contemporary to me because the author try to evaluate motivation and awareness (as subjective factors) with objective method - Q - methodology. I used these ideas and cite them in my PhD

  • Faris Alshubiri asked a question in Financial Economics:
    If any one help me how to measure the social responsibility as quantitative financial or economic methods?

    I need if any one provide me  about the measures of financial and economic quantitative methods (ratios) or (factors) to measure the social responsibility or the social behavior  

  • Gilberto L. B. Aquino added an answer in Chalcones:
    Problem in chalcone synthesis.
    In a part of my research, I am synthesizing a chalcone from 2-4-dihydroxy acetophenone and various benzaldehyde derivatives. I am following your procedure published in article but I could not get the success in the reactions so please help me.
    Gilberto L. B. Aquino

    In this case is better use acid conditions as tionylchloride in methanol!

  • Victor Christianto asked a question in NASA:
    Is there a viable warp drive technology in horizon?

    According to recent news, NASa's test with emDrive technology seems to be unsuccessful, but hope is still there. Do you know a realistic and viable warp drive technology in horizon, which possible can be put to test within ten years or so?

    your comments are welcome

  • Tobias Pehrsson asked a question in Theory of the Firm:
    Is appropriability regime essentially related to the theory of the firm?

    Or, put differently, is the theory of the firm essential for the appropriability regime?

  • Mazhar Dhankot asked a question in SAP2000:
    I am looking for modelling of a confined masonry structure is SAP2000. Can anyone suggest a method to connect the RC tie member with brick masonry?

    Joint between RC tie member and birck masonry is very critical in brick masonry structure. The toothing which is provided in confined masonry structure imparts part fixity with Brick wall. How to simulate that condition in SAP2000?

  • K. Prakash Kumar added an answer in Electrical Power Systems:
    Why, as we increase the switching frequency, must the power rating be sacrificed?

    How we can relate switching frequency and power rating of power semiconducting devices? i know its inverse. As we increase the switching frequency power rating must be sacrificed. But i want to know why??

    K. Prakash Kumar

    dear Kamaraju,

    Though electronics is not my area, let me explain simply.

    Making and breaking a current of milli amps may be done at a very faster rate. But imagine the same with a few hundreds of amps. For each making and breaking, it requires some time for the other parameters like heat dissipation etc to recover. Right? And that puts a capping on the frequency. 

  • Godfrey Omare Mauti asked a question in Weevils:
    Which bioassay methods are suitable in determining pesticide repellency test on weevils?

    Explain more on Garcia et al (1990) method of using glass tubings.

    Talk also about the Y-tube olfactometer

  • Bhattacharya Chanu added an answer in Aggression:
    Is anyone aware of aggression management and aggression prevention protocol in psychiatric nursing care area?

    Violence prevention and restraining patient is one of the management  area but restraining has an issue of ethics , human rights and law..Aggression prevention need lots of communication protocols ,gestures etc .Environment,process of work doing by health professionals sometime creates aggression .Human resources must be expert to prevent aggression.  

    Bhattacharya Chanu

    Is it the effect of mail hormones?

  • Victor Christianto asked a question in Nevada:
    Could Tesla's gigafactory be obsolete before it even opens?

    In January, Fuji Pigment Co. Ltd. (not affiliated with Fujifilm) announced that it had made a significant breakthrough in aluminum-air battery technology. According to a report, this innovation could possibly make obsolete Tesla's giga battery factory in Nevada.

    What do you think?

  • Sandeep K Nainappagari added an answer in Smart Grid:
    Is there any architecture existing which employs cloud computing for smart grid?

    Hi every one!

    I intend to workout in the domain of smart grid and interested in architectural model based on cloud computing for smart grid, I have searched over internet but not find any such architecture.

    Can some one guide me in this regards, i.e what are the existing architectures for smart grid, is any architecture based on cloud??

    Thank you in advance 

    Sandeep K Nainappagari

    The smart resource selector once again brings the data interaction in the grid. I have gone through this ieee publication http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5622089&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D5622089. I will also recommend you on Virtual power plant based cloud architecture because it's the growing trend in the industry. Resource allocation, optimized energy loss utilization are other important factors. And Fyi the virual power plants have localized generation as a part of it and utilization of energy in the local geographical area itself brings the intelligence in the grid and your so called optimized source of energy is broought in to the picture. 

  • Ken Alexander Penaso Bautro asked a question in Resistant Starch:
    Can you help me out with this article on RESISTANT STARCH published in ScienceDirect?

    I am currently studying on RESISTANT STARCH.
    I don't have access to that article, entitled:

    Resistant starch—a review of the physical properties and biological impact of RS3

    S.G Haralampu


  • Agnes Mbonyiryivuze added an answer in Skill Acquisition:
    What are important skills for PhD students ( or candidates) to facilitate their success in research?

    This question applies to any person having any idea to help PhD student as well as masters students who are willing to do their PhD in future. Some important skills are imperative to be able get a PhD and continue in research field succesfuly. I would like you to assist me in providing the most important  skills for PhD student especially the one in Sciences (Physics). 

    Agnes Mbonyiryivuze

    Dear Prof. Ivo Carneiro de Sousa, 

    Thank you very much for your support. I was really wondering many question as I am now at the beginning of my PhD. I am very happy as all provided answers to my question are so motivational, helpful and informative. 

    I am going to read all these document you provided for me and I am sure it will help me a lot. Thank you very much again.

  • Béatrice Marianne Ewalds-Kvist added an answer in Regression Analysis:
    Can we compare betas of two different regression analyses ?

    Dear All,

    Is there any method/creteria to standardize regression coefficients coming from different regressions.


    We want to compare regression beta's coming from two  different regressions.

    Béatrice Marianne Ewalds-Kvist

    If you look at my mouse papers  you see that we draw regressions lines side by side and calculated manually the difference between them. 

  • Neeraj Sethiya added an answer in Thin Layer Chromatography :
    How to extract Jasmonic acid from plant leaves for High Performance Thin Layer Chromatography (HPTLC) isolation and quantification?

    I am doing a research on the effect of priming to the levels of jasmonic acid produced by a plant. I will be using the leaves, and to quantify it, I will beusing HPTLC.

    Neeraj Sethiya

    May these links help you.

    + 1 more attachment

  • Sandeep K Nainappagari asked a question in Grid:
    How a simplified equivalent Gas Turbine power plant can be represented in matlab?

    I am currently working on a production forecast simulation in matlab. Where I have renewable with future weather forecast as input and my model says how much is the total day ahead energy production forecast. Also, it shows up the periods where the intermittent grid production leads to grid uncertainity. Later, my ISO or the so called Smart Grid Management from my model will know when to turn on the Gas Turbine. I am working on Matlab at the moment. So if someone suggests me an idea to implement a GT eqt model with gain parameters, it would be great. 

    Thank you for your time.


  • Ksh. Newton Singh added an answer in Big Bang:
    Are particles created from the energy released during the Big Bang? During expansion, does the energy continuous converted into matters?

    We have learnt from the big bang cosmology that all the particles was created after the big bang explosion. My question is that whether these particles was created from the energy released due to the big bang? If yes, the energy density must be decreases during the course of expansion as it is continuously converting into masses or matters. Again if it happens so, the mass of universe must be increasing with time or expansion.

    Please some give some light on it. I'm working on a solution of Einstein's field equations and I got an expanding solution with an initial singularity. As the time increase to future, its mass and radius increases. So I need to explain the increase in mass with time.

    Ksh. Newton Singh

    @ Andrew

     You are right. Now let me try to incorporate a least the cosmological constant. For others like primordial BH i have poor idea about how they influence on evolution of universe. 

  • Simon N Waddington added an answer in Transfection:
    How to transfect primary murine NK cells?

    Does anybody have experience with the transfection of primary murine NK cells? I would like to take my mRNA experiments to a new level and verify my findings, but as far as I read it is not so easy to transfect them. Since this is an important part of my Master project I would be very thankful for any advice.

    Simon N Waddington

    Dear Hela,

    Indeed, I don't think it's easy. Although the reference below doesn't refer directly to NK cells, it might send you along the right track

    Amirache F, Levy C, Costa C, Mangeot PE, Torbett BE, Wang CX, Negre D, Cosset FL, and Verhoeyen E. (2014) Mystery solved: VSV-G-LVs do not allow efficient gene transfer into unstimulated T cells, B cells, and HSCs because they lack the LDL receptor. Blood 123, 1422-1424

    BW, Simon

  • Sudha Balagopalan added an answer in Low Power:
    In an open circuit test, current is drawn at low power factor?

    In case of transformer why in open circuit test, current is drawn at low power factor? and in case of short ckt test why current is not drawn at high power factor? Please explain.

    Sudha Balagopalan

    Dear Anurag, Any open circuit test on any electric machine is designed to test one of the two major materials, which is iron,  used in the machine make-up. ( The no-load test on rotating machines is an equivalent of this test) This test can be interpreted as being conducted to see how effective the transformation of magnetic energy to motive power or transformation to another voltage level ( in transformers) is. 

    Hence only magnetic energy is put in when we open circuit the secondary of the transformer and no demand is made by the secondary coils for supplying the load from the source, as reflected current. Hence only magnetism is at work but due to the cyclic nature of the magnetic current hysteresis  and eddy current losses are manifested as power loss or heat. But such losses are designed to be very low since these losses contribute to all day losses. Thus the current drawn from the source, when the transformer is open circuited ( or the machine is on no load) has to subscribe mostly to creating the magnetic field and very little to the losses due to hysteresis and eddy current flow based loss. Clearly this current is lagging with respect to the applied voltage almost 90 degrees. This means a low power factor operation.

    At full load or short circuit operation conducted at low voltages, this magnetism related losses are very low. The current drawn from the source is almost fully for supplying the short circuit ( which in the controlled load- only rated current) and hence the power taken from the input is almost fully spent in the copper/ Al. conductors of the machine and the shorting conductors with a very small magnetic component. Hence the current drawn is very much in phase with the applied voltage. Thus almost upf operation is made possible.

    Hope the detailing helps!

  • Md Irfanul Haque Siddiqui added an answer in FLUENT:
    What is ANSYS FLUENT’s volume of fluid (VOF) multiphase modeling?

    can any body explain the VOF model. what is the significance of this model. when it is used.

    Md Irfanul Haque Siddiqui

    VOF model will be more useful if the study is focused on interface tracking. Otherwise mixing study can be modelled using mixture model of Fluent.

  • Kai Zhao asked a question in Kinetic Monte Carlo:
    How to simulate the diffusion of impurities (i.e., H, He,...) in metals by kinetic monte carlo (kMC)?

    Hi everyone,

    I want to simulate the diffusion of impurities (i.e., H, He,...) in metals by kinetic monte carlo (kMC). Can you recommand a kMC code that is suitable for the simulation?

  • Marcel M. Lambrechts added an answer in Science Education:
    What ways have you found to be effective to deal with students' misconceptions in science?

    My students learn biology and other sciences in English. Recently they had the Mid-semester test. Two of my 90 students had an F grade. When I checked their answers I found they had many misconceptions. Even simple questions like formation of a dipeptide; simple structure of a nucleotide were wrongly answered. The students admitted that they studied at the last minute.

    Any suggestions how to help such students with their misconceptions/confusions? I I believe it is related to their lack of motivation.  They take life easy; so different from the time when I was a student.  All my class mates worked hard to achieve, for the sake of our families.  Besides that, we found that science was interesting, and this fueled our curiosity.

    Marcel M. Lambrechts

    Thus, my answer to the initial question: I give children/students/people the time to learn, each at their own individual-specific rhythm (Learning must remain a pleasure)!

  • Faris Alshubiri asked a question in Financial Economics:
    Can any one provide me financial and economic quantitative methods (ratios )or (factors ) to measure the entrepreneurship i?

    I need to help me if there are financial and economic quantitative methods (ratios )or (factors ) to measure the entrepreneurship ?

  • Jeremy Ham added an answer in Social Media in Education:
    Which types of Social Media Social Networks do you use for your teaching in a university/college classroom?

    If you are interested we are also running a survey. If you want to participate drop me a message

    Jeremy Ham

    We started using Ning.com- which has a great interface and operates 'outside' of the students FB networks- but they started charging, so we went to FB. Check the diagrams in the attached paper outlining the various ways students engage in SN in relation to design studio education...https://www.researchgate.net/publication/275823340_The_Social_Network_Learning_Cloud_Architectural_Education_for_the_21_st_Century

    The big question is What SN are you using, and Why do you use them

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: In less than a decade, architectural education has completely changed. The advent of computation has not so much triggered the change, but Social Networks (SN) have ignited a novel way of learning, interaction and knowledge construction. SN enable learners to engage with friends, tutors, professionals and peers, form the base for learning resources, allow students to make their voices heard, to listen to other views and much more. They offer a more authentic, inter-professional and integrated problem based, Just-in-Time (JIT), Just-in-Place (JIP) learning. Online SN work in close association with offline SN to form a blended social learning realm – the Social Network Learning Cloud (SNLC) – that greatly enables and enhances students' learning in a far more influential way than any other learning means, resources or methods do. This paper presents a SNLC for architectural education that provides opportunities for linking the academic Learning Management Systems (LMS) with private or professional SN such that it enhances the learning experience and deepens the knowledge of the students. The paper proposes ways of utilising SNLC in other learning and teaching areas of the curriculum and concludes with directions of how SNLC then may be employed in professional settings.
      International Journal of Architectural Computing 09/2014; 12(2):225-242. DOI:10.1260/1478-0771.12.3.225
  • Chen Gafni added an answer in Praat:
    How do I calculate the Breathiness Index?

    I am trying to calculate the Breathiness Index, suggested by Fukazawa et al. (1988), as a measure for breathy voice. The paper indicates a range of 8.3 to 75.7 for values of BRI, but my calculations yield values at an order of 1015.

    I refer to the definition of BRI as the ratio between the energy of the second derivative of a signal and the energy of the non-derived signal.

    I performed the analysis in Praat. The original sound was converted to a matrix, then I applied a formula ((self [col+1] - self [col]) / dx) twice, to obtain the second derivative, and cast the matrix to a sound. Energy was calculated using the Get energy command (which calculates the integral of the squared signal between two time points).

    Any idea what I am missing here?

    Alternatively, can anyone suggest another measure for spectral tilt that does not require an arbitrary cut-off frequency between low and high frequencies?

    Chen Gafni

    On second thought, I expect the discrete calculation to give similar results to the continuous calculation (with some error, of course). The results I received are many orders of magnitude far from what I have seen in the Fukazawa paper (see link). So either, I misread their results (I'm referring to the first paragraph of their results), or didn't get the procedure right.

  • Morteza Amjadi added an answer in PDMS:
    Can I deposit ITO (Indium tin Oxide) on cured PDMS using E-Beam evaporator and anneal it after that? to what annealing temperature does PDMS hold ?

    I am trying to deposit ITO on PDMS, will i be facing a problem in adhesion or annealing or any other problems ?

    Morteza Amjadi

    PET is much stiffer that PDMS film and its easy to handle ITO over PET.

  • Benji Bryan Silva asked a question in Salicylic Acid:
    How can I quantify salicylic acid from plant leaves using spectrophotometry?

    I am trying to establish the effect of priming (using a fungus) to a plant.I want to determine the level of and changes in the amount of salicylic acid as time progresses. 

    I was not allowed to use liquid nitrogen for extraction due to some technical reasons, so I am hoping for a method which will allow me to extract  salicylic acid without liquid nitrogen and quantify it using spectrophotometry.