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  • Abdelwahab Fawzy asked a question in Genetic Algorithm:
    Use of Genetic Algorithm in WSN routing?

    * can any one help me in employing of genetic algorithm in WSN routing
    either in detection of optimum (CH) cluster heads or location of CH even the optimum propability of CH selection in LEACH protocol ..........etc

    *Can anyone help me get a source code of  any routing protocol dealing with GA.

  • Ouassim Rahmouni added an answer in Slope Stability:
    Is there any new method for determination of slope stability problems?

    is any new method for determination of slope stability problems ?

  • Emeka W. Dumbili added an answer in Publications:
    Where is the option of sharing publication, in new format of RG?

    In new design of RG, I am unable to get the option of sharing publications. Please help me.

    Thanks in advance.

    Emeka W. Dumbili · Brunel University London

    I am not resistant to change, but I preferred the previous format.

  • John F. Wilhite added an answer in Humanities:
    BA & BS are 3 years in UK, Germany etc while 4 years in USA & many other countries, which one is better ?

    What are the pros & cons of 3 years undergraduate (as in UK) versus 4 years undergraduate (as in USA) ? Just only courses related to major or additionally general courses as humanities etc ? Which one would you prefer if you were the student with these two alternatives ?  

    John F. Wilhite · University of Tennessee

    When it comes to education more is always better than less.  But number of years doesn't solve the problem that many graduates today are not as well educated and qualified for employment as in the recent past (in the US, I don't know about other countries.

  • Catherine M G C Renard added an answer in Postharvest:
    Any body with any suggestions on low cost and simple (non-sophisticated) techniques for preserving tropical fruits?

    The postharvest losses of fruits in the tropics is very high and there are continuous efforts being exerted to overcome this challenge. I just wanted to here some research findings and/or success stories of simple and affordable technologies applied in other areas.

    Catherine M G C Renard · French National Institute for Agricultural Research

    Cooling and O2 decrease are the first basic actions to decrease metabolism. The difficulty lies in the energy for cooling. I remember seeing a presentation of solar-powered containers for fruit shipping once, that might be a good start.

  • Alshaimaa Mustafa asked a question in SLA:
    Are there any real data of cloud?

    I need a data to do my experiment results on the SLA parameters of cloud providers such as Availability, Reliabiltiy, Reputation.

  • Ahmed S. Moharram added an answer in CMC:
    What is the best method to determine Critical Micelle concentration (CMC) of a polymer ?

    I want to determine CMC of a new polymeric catalyst experimentally. Is there a way of obtaining it using UV-vis Spectroscopy ?

    Ahmed S. Moharram · Assiut University

    This paper explains how to determine CMC using UV-vis Spectroscopy in details

  • Akram Mahoodi added an answer in Inductor:
    What is an inductor? How do inductors behave?

    What is an inductor? How do inductors behave?

    Akram Mahoodi · Khorasan Institute of Higher Education

    Inductor or Reactor or Choke is a coil with air core or magnetic core. Inductance is measured in henries. Rise of current is delayed due to inductor. Chokes are used for many purposes. Current limiting chokes, filter chokes, chokes for harmonic suppression etc. Choke or Inductors are used in AC/DC Drives, Invertors, Power System, lighting circuits, Furnaces. Frequency, voltage and inductance depend upon use.

  • Akram Mahoodi added an answer in Transformers:
    What is the inductance of a transformer?

    What is the inductance of a transformer?

    Akram Mahoodi · Khorasan Institute of Higher Education

    Winding of transformer associated with electromagnetism will have Resistance, Inductance and Impedance. These parameters depend upon various factors such as frequency, physical dimensions, operating flux density.

  • Akram Mahoodi added an answer in Transformers:
    Can I connect a single-phase transformer to a three-phase source?

    Can I connect a single-phase transformer to a three-phase source?

    Akram Mahoodi · Khorasan Institute of Higher Education

    No you cannot connect single phase transformer to three phase circuit without confirming circuit configuration. Transformer primary designed for line to line voltage can be connected across two phases. Transformer designed for phase to neutral voltage can be connected across phase and neutral.

  • Akram Mahoodi added an answer in Transformers:
    What is an isolating transformer?

    What is an isolating transformer?

    Akram Mahoodi · Khorasan Institute of Higher Education

    Isolation transformer means any transformers where two winding are isolated from each other electrically.

  • Masoud Darbasi added an answer in Edible Films:
    Which material is better to use for making antimicrobial and antioxidant edible film for food?

    Hello to everyone

    I want to make an antimicrobial and antioxidant edible film for food products but I want to use a material that is inexpensive and highly available for food industry and its construction and other properties is well known for modifications.

    thanks

    Masoud Darbasi · University of Tehran

    Thanks a lot for you

  • Akram Mahoodi added an answer in Transformers:
    Why is the transformer case hot?

    Why is the transformer case hot?

    Akram Mahoodi · Khorasan Institute of Higher Education


    Resistance of transformer winding is responsible for generating watt loss. Similarly transformer core also contributes to watt loss in magnetic circuit. There are other types of losses such as Eddy Current loss, Stray loss etc. All these losses generate heat and temperature of winding, core, enclosure increases.
    Humming noise is created by electromagnetic circuit and core. Wherever it is required and essential it can be minimized by dampening pads (for small transformers).

  • Jonathan Edwards added an answer in Qualia:
    A thought experiment inspired by Chalmers' “Fading Qualia”. What manipulations to the neural circuitry demolishes consciousness?

    Instead of gradually replacing biological neurons with silicon neurons as in Chalmers' Fading Qualia, I attempt to gradually replace dividable functions of biological neurons with silicon emulation.

    The question is, at which manipulation stage does our brain lose consciousness (qualia)?

    1)   Replacement of axonal spike propagation with an external artificial mechanism that uses radio transmission (e.g. WiFi): Causality between presynaptic neuronal firings and postsynaptic PSPs is preserved, but now neurons are physically isolated.

    2)   Further replacement of postsynaptic PSP integration with an external artificial mechanism: Causality between presynaptic neuronal firings and postsynaptic somatic membrane potential is preserved, but now without sophisticated dendritic-somatic computation.

    3)   Further replacement of transformation from postsynaptic somatic membrane potential to postsynaptic firing (Hodgkin-Huxley Eq. mechanisms) with an external artificial mechanism that integrates presynaptic firings and activates postsynaptic neurons by current injection accordingly: Causality between presynaptic neuronal firings and postsynaptic neuronal firings is preserved, but now without an intact internal variable, the membrane potential.

    4)   Mere replay of spatio-temporal neuronal firing patterns by external current injection: Zero causal interactions among neurons.

    Jonathan Edwards · University College London

    Masataka,

    Spreading to network dynamics is non-local, as I have said. Physics does not allow it. There is no point in having interpretation in a series of events because at each new event you have to interpret again. Interpretation is not carried over in the world. You have the infinite regress of the homunculus. All networks can do is turn one set of signals into another set of similar signals - nothing achieved.

    The only solution is Descartes's solution - the 'interpretation' comes free with the immediate local relation of input. There is no reason to suggest otherwise (since as indicated above it achieves nothing) and there is no need to violate what we already have in physics since physics leaves 'interpretation' to the observing event.

  • Akram Mahoodi added an answer in Transformers:
    Can transformers be used in parallel?

    Can transformers be used in parallel?

    Akram Mahoodi · Khorasan Institute of Higher Education

    Transformers are frequently use in parallel in power system but voltage ratio has to be equal. The load sharing between two transformers depend upon their impedance.

  • Akram Mahoodi added an answer in Transformers:
    What is an transformer electronic?

    What is an transformer electronic?

    Akram Mahoodi · Khorasan Institute of Higher Education

    There is no Electronic Transformer as such. But transformers are required in Electronic Equipment for various purposes such as step down transformer, auto transformer, isolation transformer, transformers for rectifier circuits etc. The operating frequency ranges from 50/60HZ to many Kilo Hz or Mega HZ

  • Akram Mahoodi added an answer in Transformers:
    Why did my transformer blow the moment it was installed?

    Why did my transformer blow the moment it was installed?

    Akram Mahoodi · Khorasan Institute of Higher Education

    1) connected to higher voltage than it was designed for.
    2) There was a short circuit on load side.
    3) There was a fault in the transformer.

  • Muhammad Sohaib asked a question in Server:
    Is there any free server available for MD simulations of protein ?

    Hi Everyone

    Can anyone suggest me any free server available for MD Simulations of protein and ligand-protein?

    Regards!

  • Alexander Hektorsson asked a question in Interpretative Phenomenological Analysis:
    When devising a semi-structured interview schedule in IPA, is it a problem if a question is likely to generate a superordinate theme?

    Semi structured interview schedule (Interpretative Phenomenological Analysis)

    Hello, I am preparing an interview schedule for a qualitative study on the experiences of GP’s loving feelings for their patients. The aim of the study would aim at understanding the meaning of those feelings, which effect they have on practitioners and how they manage those feelings. Smith’s IPA book suggest to prepare questions for each area that we want to investigate. Now in IPA it is paramount not to lead the participant and let them freely talk about their experiences. However if I want to investigate how GP’s manage those feelings, would it be leading to ask the question “How did you work through those feelings”?, particularly as it is likely that the question will generate a superordinate theme….It sounds as if asking questions on a particular sub area is likely to generate a superordinate theme. Is that a problem in IPA? Any help on this would be highly appreciated. Many thanks in advance!

  • Francisco José Cuadrado Méndez added an answer in Music:
    Can anyone recommend some research or journals on the positive effect of familiarity in music listening?

    I am going to write a report on exposure effect and music preference. Can anyone recommend some literatures about this topic?

    Francisco José Cuadrado Méndez · Universidad Loyola Andalucía

    Here I leave you the link to the full document: http://www.laphil.com/sites/default/files/media/pdfs/shared/education/yola/susan-hallam-music-development_research.pdf

    And the link to the journal "Psychology of Music": http://pom.sagepub.com/

    If you need more specific works don't hesitate to ask me about. I may find some research studies that may help you.

  • Akram Mahoodi added an answer in Transformers:
    Can transformers be operated at various frequencies?

    Can transformers be operated at various frequencies?

    Akram Mahoodi · Khorasan Institute of Higher Education

    Transformers are designed for a particular frequency as required by use. Transformer designed for higher frequency cannot be used at lower frequency. But a transformer designed for lower frequency can be used for higher frequency subject to many considerations and limits on performance.

  • Jack Silver added an answer in Camellia sinensis:
    What is this compound from Camellia sinensis (green tea) at ~548 Da?

    I'm purifying compounds from a RediSep Rf Strong Cation Exchange column on a Teledyne Isco EZ Prep system with a PurIon mass spectrometer system.

    I dissolved methanolic extract of green tea in methanol containing acetic acid, and loaded it on the SCX column, washed the column with methanol, and ran the column according to the attached PDF. The first gradient (using water/ 5% acetic acid) washed off the xanthine alkaloids; I could see caffeine and theophylline in the mass spectrum.

    The second gradient uses 5% ammonium hydroxide in water, and washes off stronger bases. During this second gradient, I recovered the sharp peak at ~47.4 column volumes (CV). The mass spectrum shows a peak at 549, suggesting possible masses of 548, 526 (if I'm looking at a [M+Na]+ at 549), or 516 (if my mass peak is an adduct of [M+MeOH+H]+ ). I'm using methanol as a carrier solvent.

    It isn't a flavanoid or other phenolic compound since I'm using a cation exchange column. I haven't found a hit yet in the ACS journals, nor yet on http://www.ebi.ac.uk/chebi/

    Any ideas what this could be? I guessing either an alkaloid or some small peptide?

    Thanks in advance.

    Jack Silver · Teledyne ISCO, Inc

    @ Dr. Coulerie- interesting, I'll keep this in mind. Would you expect it to elute from an SCX (strong cation exchange) column? They appear acidic to me.

    Another possibility is some sort of compound related to chlorophyll.

  • Hong-su Park added an answer in 293T:
    Why do transduced 293T cells die before selection?

    I just transduced 293T cells with lentiviruses for MLKL knockdown.

    Even without puromycin, many of them look round and eventually die, while mock-transduced cells are ok.

    Is this knockdown lethal for these cells?

    Actually, MLKL knockdown is known to inhibit necroptosis, so it would not lead to cell death at least, I thought. And others successfully knocked down the gene in another human cell line, HT-29.

    Any suggestions?

    Hong-su Park

    Hello, Jill.

    It's been okay with other lentiviruses. And the cells looked well when transfected with transfer plasmid plus envelope and packaging plasmids. I could confirm the knockdown from the cells transfected. So I'm just trying to use the transfected cells for further steps, not establishing a stable cell line.

  • Mostafa Mashmoul added an answer in Transformers:
    What is an Isolation Transformer?

    What is an Isolation Transformer?

    Mostafa Mashmoul · Khorasan Institute of Higher Education

    It is a transformer that insulates the primary circuit from the secondary circuit. Also referred to as a two-winding or insulating transformer.

  • Nina Jährling added an answer in Zebrafish:
    What is the latest understanding about the coronary vessel development in Zebrafish?

    please suggest me some recent mostly cited review articles about coronary vessel development in zebrafish and scientists working this emerging area. Please suggest also the protocols and techniques widely followed in the zebrafish research.

    Nina Jährling · Vienna University of Technology

    Did anybody tried light sheet microscopy and lectin staining?

  • Mostafa Mashmoul added an answer in Abbreviations:
    What is the abbreviation NEC?

    What is the abbreviation NEC?

    Mostafa Mashmoul · Khorasan Institute of Higher Education

    National Electric Code

  • Nina Jährling added an answer in Light Sheet Microscopy:
    How is THE ultramicroscope (UM) in the research world defined?

    Is the definition correct?:

    A  LS-setup, which generates the light-sheet (LS) passing a slit aperture and a cylindrical lens?

    I would like to enjoy this discussion with researchers, who work with light-sheet microscopy in the field of optics.

    Best wishes from Vienna,

    Nina Jährling 

    Nina Jährling · Vienna University of Technology

    One idea:

    Ultramicroscopy (UM):

    Standard system (UM): Slit aperture+ Cylindrical lens => Thin Laser Lightsheet & Transparent Specimen=>3D reconstruction

    Please discuss with me  ;-)

    Best wishes,
    Nina

  • Mostafa Mashmoul added an answer in Abbreviations:
    What is the abbreviation NEMA?

    What is the abbreviation NEMA?

    Mostafa Mashmoul · Khorasan Institute of Higher Education

    National Electrical Manufacturers Association.