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  • Andreas Leineweber added an answer in Energy:
    Why does stacking of fault energy increase with temperature in F.C.C crystals and decrease with temperature in H.C.P crystals?

    Why does stacking fault energy increase with temperature in F.C.C crystals and decrease with temperature in H.C.P crystals?

    Andreas Leineweber · Technische Universität Bergakademie Freiberg

    Can you give a source for this observation?

  • Abbas Rahdar asked a question in Doping:
    What is difference between interstitial doping and substitutional doping? for example ?

    what is difference between interstitial doping and substitutional doping? for example ?

  • Ahmad Deel added an answer in CST Microwave Studio:
    How can I design a monopole antenna in cst?

    Hi everyone,

    I initiated to design a monopole antenna for particular frequency. what are the design considerations of a monopole antenna and what are the available feeding methods to the element. The available software tool for me is CST Microwave Studio Suite.please help me in this regard and i would very thankful to you.

    thank you.

    Ahmad Deel · Shiraz University

    If you mean simple wire monopole antenna; its easy;

    Draw a vertical wire with radius a and height slightly smaller than (lambda / 4).

    Draw a ground plane (circular plane is a good choice) larger than lambda.

    Place the Wire (g mm) above ground; g is a gap between antenna and ground plane and is in the order of (lambda / 100).

    Excite the antenna with the defining the point source from the center of ground to center of wire antenna

  • Wasiff Syed asked a question in Internet of Things:
    What is the impact of internet of things in supply chain ?

    i need information 

  • Kimmo Korhonen added an answer in RTP:
    Can anyone explain why Reduction to pole(RTP) value of total magnetic field deviates after a certain limit of total magnetic field?

    Can anyone explain why Reduction to pole(RTP) value of total magnetic field deviates after a certain limit of total magnetic field(very high magnetic anomaly) ..that is calculated from magnetic field calculator for determining inclination and declination which is used for RTP calculation ? RTP  basically reduces the anomalies to those that would be observed at Magnetic north pole with a vertical remnant magnetization direction?? Explain the reasons in detail??

    Kimmo Korhonen · Geological Survey of Finland

    Maybe it is a problem with numerics?

    Are your values measured near the equator?

    You could also experiment with synthetic data to see whether your algorithm is working correctly.

  • How can I troubleshoot no PCR product (nuclear DNA and microsatellites) problem in outgroups within the same genus and within the same family?

    I am trying to amplify seven SSR loci, that I used to genotype my study species individuals, in 2 out-group species (within same genus and within same family). I am getting amplification for 2 loci in individuals belonging to the same family using the same protocol that I optimize before but other 5 loci are not amplifying. Also, no loci amplified in individuals belonging to the same genus. DNA concentration for out-group individuals within the same genus = 5ng/ul and within same family = 3 ng/ul. I would appreciate it if anyone could suggest anything about this problem.

    Note: I have already tried touchdown PCR annealing temperature variable


    Elena Yu. Filinova · Advanced Biomedical Research Laboratory, RF; Vidipharm Gmbh, Austria

    SNIP regions or repeat might appear inside variable zones of gene of new individual if primer arrangement was not tested with enough cases before. Maybe primers design-arrangement should be checked again if your controls amplify normally.

  • Sedat Kula added an answer in Social Research:
    When using secondary data in social research, can we compare the two countries' data collected in different years?

    One country data collected in 2008, other country data collected in 2010.

    Sedat Kula · Turkish National Police

    Thanks a lot for your response

  • John R Tracy added an answer in Empowerment:
    What is the difference between Empowerment and Self-Regulation Learning?
    EMPOWERMENT can be thought of as a process by which individuals gain control over their lives (Perkins & Zimmerman, 1995). Empowered individuals often exhibit various self-regulatory qualities such as high self-efficacy perceptions and a sense of agency or personal control.
    (Cleary, T. J., & Zimmerman, B. J. (2004). Self-regulation empowerment program: A school-based program to enhance self-regulated and self-motivated cycles of student learning. Psychology in the Schools, 41(5), 537–550. doi:10.1002/pits.10177)

    SELF REGULATION LEARNING is the degree to which students are metacognitively, motivationally and behaviorally active participants in their own learning process (Zimmerman,1986). This definition focused on students’ proactive use of specific processes or responses to improve their academic achievement.
    (Zimmerman, B. J. “Investigating Self-Regulation and Motivation: Historical Background, Methodological Developments, and Future Prospects.” American Educational Research Journal 45, no. 1 (March 1, 2008): 166–183.)
    John R Tracy · Spanish Peaks Behavioral Health Centers, Pueblo, CO


    You tread upon a very important issue that is difficult to navigate due to multiple factors including Western Rational Thinking at it's perceptual framework. As Douglas pointed out, Freire addressed this in his way, but he has been mostly marginalized by mainstream academia due not just language issues,, but also societal-cultural issues and differences. 

    I add to your thoughts and questions by bringing up a framework I have developed that lends some insight into the matter. This is what I call my Actualization Diagnostic Construct (you may find it in more detail in my dissertation  available on my site in Research Gate). 

    Essentially, I differentiate the issues and definitions related to empowerment and self-regulation or actualization. I see actualization as n ongoing process in which there is no hierarchy or Pyramid as in Maslow's Hierarchy. I see that learning linked with insight or maturation is developmental and a matter of holding enough openness and seeking to know that the opportunity is there to gain new insight. It is also vital to know that insight is at best momentary and always changing and that it cannot be treated as Truth beyond the moment. Love, for example, must be rediscovered and again and again and it is different each time it is discovered. never the same. It is only int the position of Open and Seeking that we have the hope of learning at the level of wisdom. The rest is simply information gathering

    Take care,

    John White Eagle Tracy.

  • Sujata Banerjee asked a question in Articles:
    Is there any research artcles on foreign directors in indian context?

    is there any articles highlighiting on the usefullness of  foreign directors in the indian context?

  • How can South-South health cooperation be improved?

    What are your thoughts on improving regional knowledge sharing in East, Central and Southern Africa? http://bit.ly/1xF80tb

    Norbert Boruett · Masinde Muliro University of Science and Technology

    Already here in East Africa and think in the south there are  a number of initiative most of the inter governmental, i am sure of the names i know there is serious organisation at Arusha, some with nepad? what i am saying, lets not reinvent the wheel, but employ synergy

  • Does “spin” imply physical rotation?

    The “spin” of an electron or other fundamental particle is often described as “intrinsic angular momentum”. This terminology is required because a point particle or Planck length vibrating string cannot possess ½ ħ of angular momentum. Larger objects such as molecules or electrons in atomic orbitals possess quantized angular momentum which can be demonstrated to involve physical rotation. For example, a carbon monoxide molecule in a vacuum can only rotate at integer multiples of 115 GHz which is integer multiples of ½ ħ. Therefore, do you believe that fundamental particles have a physical angular momentum that is currently not understood? Alternatively, is "intrinsic angular momentum" an accurate description of spin because it is a quantum mechanical property that does not involve physical rotation?

    Anatolij K. Prykarpatski · AGH University of Science and Technology in Kraków

    To @Kimmo Rouvari

    You wrote: Kind of funny that you keep on talking about Einstein's nonlocal hidden variables... after all, Einstein himself was against such an idea" - yet, you know well that it menas  nothing - as it is well known that Einstein many times was changing his mind about diverse important physical entities, - as, for instance,  about  ether, about light quanta and so on... Any human can fall into fake thinking, it is not so dangerous as there exist alot other sound thinking people who will correct a not properly  chosen  way and  science will prosper ahead...

    Keep well -   Happy New Year and  Merry  Season's Holidays to all!



  • Krishna Kumar Yadav added an answer in Drought:
    What is the relation of climate change affecting rainfall and drought in a particular place?

    Climate change is a major role played in the excess of rainfall and drought. If we are observing one place then how can the two occur. I wonder how climate change can be responsible for drought and rainfall? Are they opposite to each other?

    Krishna Kumar Yadav · Bundelkhand University Jhansi, India

    Thanks to all for your valuable suggestions

  • How can we find the sensitivity of parameters in Artificial Neural networks?

    In an artificial neural network I have 20 different input parameters and 4 output parameters. I want to train the feed forward network but first predict which parameter is more sensitive and which is less sensitive.

    Instead of PCA you could calculate cross-covariance matrix and then calculate its SVD (sort of canonical correlation analysis) and find which variables have high correlation.

  • Irena Pawlak added an answer in Pancreatic Cancer:
    What is a recent, modern and advanced treatment of pancreatic cancer?

    Surgical management.

    Irena Pawlak · Keiser University


  • What is the experimental basis of the first Maxwell equation in ELECTRODYNAMICS (div D=ro)?

    As we know this equation in electrostatics is based on Coulomb experiments, but this is not obvious in electrodynamics. 

    Nagendra Singh · University of Alabama in Huntsville

    Dear Mohammad,

        As I had pointed out earlier, the charge conservation from electrodynamic equations follows only after adding the displacement current in the Ampere's law, a dicovery by Maxwell.

       Which other form you are referring to? The differential and integral forms are the ways of writing Maxwell equations. The both forms are equivalent; in the integral form the time derivative of the total displacement current threading an appropriate closed surface enters the equation while in the differential form it is the time derivative of the displacement current density at a point. The Kirchoff's current law represents the integral form. Thus the Kirchoff's current law applied to any time-varying circuit containing charge-storage devices (like a capacitor) could be an experimantal verification of the modified Ampere's law.

    Happy new year

  • Do you know of any MRI image database?

    I would like to do research on MRI images. Can you please suggest some websites from where MRI images can be downloaded. Thanking you. Gautam Talukdar. 

    Ersin Yavas · University of Leicester

    Dear Talukdar,

    You can check the websites;

    - Basics of MRI: http://www.cis.rit.edu/htbooks/mri/

    - Revise MRI: http://www.revisemri.com/questions/basicphysics/

    - Questions and Answers in MRI: http://mri-q.com/index.html

  • Mohamed El Naschie added an answer in Fuzzy:
    Could you use the theory attached for the same problem?

    From Highly Structured E-Infinity Rings and Transfinite Maximally Symmetric Manifolds to the Dark Energy Density of the Cosmos
    DownloadDownload as PDF (Size:2562KB) HTML XML PP. 641-648
    DOI: 10.4236/apm.2014.412073 191 Downloads 240 Views
    Author(s) Leave a comment Mohamed S. El Naschie1*
    1Department of Physics, University of Alexandria, Alexandria, Egypt.
    Starting from well established results in pure mathematics, mainly transfinite set theory, E-infinity algebra over operads, fuzzy manifolds and fuzzy Lie symmetry groups, we construct an exact Weyl scaling for the highly structured E-infinity rings corresponding to E-infinity theory of high energy physics. The final result is an exact expression for the energy density of the cosmos which agrees with previous analysis as well as accurate cosmological measurements and observations, such as COBE, WMAP and Planck. The paper is partially intended as a vivid demonstration of the power of pure mathematics in physics and cosmology.
    Highly Structured Rings, E-Infinity, Loop Spaces, High Energy Physics, Dark Energy, Einstein Relativity, Fractal-Cantorian Spacetime, Nonlinear Dynamics, Quantum Chaos
    Cite this paper
    Naschie, M. (2014) From Highly Structured E-Infinity Rings and Transfinite Maximally Symmetric Manifolds to the Dark Energy Density of the Cosmos. Advances in Pure Mathematics, 4, 641-648. doi: 10.4236/apm.2014.412073.

    Mohamed El Naschie · Alexandria University

    thank you for your replay. of course science is such that  I and the majority of researchers  could well be wrong .however I do not agree with your arguments .Remember Moscow school of mathematics

  • Ahmad Deel added an answer in Patch Antenna:
    What do I do for defining waveguide ports to design a patch antenna in cstmws with cpw structure?

    In cstmws it is mentioned that we have to use pick points on outward conductor but it shows error. How exactly do you feed this type of antenna structure?

    Ahmad Deel · Shiraz University

    I think both could work.

    But remember when you try to define wave port; you want to model waves around Microstrip line and substrate. So, the height of wave port must be bigger than substrate height (i think it should be 5 times the Substrate Height).

    And the width of port must be bigger than microstrip line width because the field is actually extended a little bit further than the Height and Width of micro-strip line.

  • Adam B Shapiro added an answer in DNA Polymerase:
    How to extract and purify cloned DNA polymerase enzyme?

    Is there any protocol to extract and purify cloned DNA polymerase enzymes from bacteria? 

    Adam B Shapiro · AstraZeneca

    Here's another reference, one of my own:


  • How can iIresolve convergence problems of thin wall shell element ?

    I am modeling a thin wall shell element column under temperature and I have 2step<first is heat and second step  is displacement control method 0.3mm/min:during of submit I have this error "too many attempted made for this incrument"in second step, first incrument :::because unstable system                          now I can't resolve convergence problems of this unstable system. Do yow know how to do it? Thanks.

    Alireza Afaghi Darabi · Babol Noshirvani University of Technology

    Hi Ms Jafarzade.

    this error is because of highly non-linearity  in analysis.means that when abaqus initiate to solve equation, the increment is large,so the software reduce the increment to be able  to solve that equation.it may be occur when you have mistake in modeling or in boundary condition.

  • Mohammed Kamel Ayasrah added an answer in Gaussian:
    Can I make segmentation of fractional Gaussian noise series to do some calculations that are related to estimate some parameters?

    Can I make segmentation of  fractional Gaussian noise series  in order to do some calculations that are related to estimate some parameters? Or  I need a reference that do it?

    Mohammed Kamel Ayasrah · Universiti Utara Malaysia

    Thanks Dr. Paul R. Yarnold for your concern . now I want to explain more about my question : I working now on stochastic volitility model and I have to estimate all parameters in this model . To do this,first  I did discritization of the model to convert it from continuous to discrete . Second : to get the estimations of the parameters I used maximum likeihood fumction but the covariance matrix is not easy to compute so as altrenative I use innovation algorithm .

    my problem : many of my calculations depend on fractional Gaussian noise process and I have to apply my program on size of 100,200,300,400 and 500 for 100 replications. This take very very long time. For that reason I thinking in dividing the fractional Gaussian noise into equal subprocesses. Then apply my program on each subprocess to get the estimations of the parameters. Finally, I will compute the average of the estimations of each parameter. This idea take too shorter time .

  • Sadagopan Parthasarathy asked a question in Heuristics:
    Is there any specific software or model to decide the routes during large religious congregations?

    In large religious congregations involving millions through narrow roads, the routes are decided by heuristic methods. This leads to more confusion. If there are established models or procedures or software to decide in a more scientific way, it will be useful.

  • Covariance matrix of the mm estimator?

    How to find the covariance matrix of the mm estimator from the estimated parameters?

    Subrata Chakraborty · Dibrugarh University

    if method of moments asymptotic cov matrix from information matrix!

  • Jan Winter added an answer in Laser Diodes:
    Why the threshold current is increased by increasing the temperature of laser diode?

    By increasing the temperature of laser diode, power is decreased.

    The reason is increasing in the threshold current of laser.

    I want to know that why the threshold current is increased by increasing the temperature of laser diode? 

    Jan Winter · Munich University of Applied Sciences

    yes, sure...

  • How can I analyze blood parameters such as hemoglobin, which is categorized as low, normal, and high?

    Medical researchers sometimes need to categorize the investigated parameters such as hemoglobin, TSH levels, BMI etc., as low, normal and high. What statistical tests do you recommend?

    Subrata Chakraborty · Dibrugarh University

    Multinomial Regression analysis

  • How to calculate sample size for survery research?

    what is the simplest formula for calculating the sample size in survey research?

    Subrata Chakraborty · Dibrugarh University

    very informative answers from Dr. Knaub

  • Nikolai I. Kobasko added an answer in Hot Forging:
    Is there someone who does have experience with AISI 51XX steels (low-alloy chromium steels)?

    I'm looking for some information on AISI 51XX steels, especially their mechanical properties after various heat treatments and/or mechanical processing (hot forging especially). I would really appreciate it if anyone would help me with this matter.

    Nikolai I. Kobasko · IQ Technologies Inc., Akron, USA and Intensive Technologies Ltd, Kyiv, Ukraine

    AISI 51XX steel with 0.80% - 1.05% chromium usually is quenched in oil to prevent crack formation. Quenching in oil doesn't provide high mechanical properties of steel. It can be quenched intensively in water flow to increase mechanical properties of material, decrease amount of cromium . Speed of water depends on size of steel component. According to our experience, chemical composition of chromium steels should be optimized and intensively quenched to increase significantly service life of steel components and decrease omount of chromium in steel.

  • Jasim Ahmed added an answer in Heat Capacity:
    Can anyone please help me find the heat capacity from my DSC results?

    I am attaching here DSC results of my powder sample. The following are the details of the sample.

    1.the sample mass (13.190mg)

    2. heating rate (10deg/min)

    3. range (-100 to 500c)

    output files contain temperature (deg. Cel.), time (min) , DSC(mW/mg) & sensitivity (uV/mW),

    From this, how can I calculate the flow rate and heat capacity & mass %

    Thanks in advance for your answers

    Jasim Ahmed · Kuwait Institute for Scientific Research

    If you are using a DSC (TA, Perkin Elmar) with software; these values you can get directly from software. You have two options either you can choose heat flow vs temperature or heat capacity vs temperature. If you do not have option for heat capacity you just calculate by proper conversion factor.