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  • Does anyone know a free plagiarism detection software I can use for a PhD thesis?
    see above
    Bahram Kazemian · Islamic Azad University Tabriz Branch

    I usually use the following one. It is free and searches all available articles, books in Google, and represents duplicate sentences and paragraphs.

  • How can I reconstruct a clear image plane digital hologram?

    As far as I know, the angular spectrum method is a good idea, but I cannot get a clear reconstructed image. Could you give me some advice?

    Tatiana Latychevskaia · University of Zurich

    Thank you, Mingquing, for uploading the two images.

    I think the problem is the quality of the hologram, it is very noisy and the interference pattern is buried under the noise. In the left top corner you have a small object, whose hologram looks about right to be reconstructed by ASM. But, I think you are interested in the large object in the center, whose hologram does not exhibit any fringe pattern (or is just problem of bmp format?). I would suggest you to get a better signal-to-noise ratio hologram and improve the visibility of (1) interference pattern given by superposition with the reference wave, and (2) interference pattern given by the object wave alone. You can check that under Fourier transform of an off-axis hologram, one should see two sidebands for +1 and -1 orders. At the moment, Fourier transform of your hologram gives only two faint spots at the currying frequencies.

  • Which gain configuration (resistor values) to choose for an inverting op-amp amplifier for the same gain?

    Hi all,

    The gain of an inverting op-amp amplifier is given as -Rf/R1. However, there can be many possible configurations depending on these resistor values, all providing the same gain. For eg: a) Rf=100M, R1=10M b) Rf=100K, R1=10K c) Rf=100, R1=10. All gives gain=10. So which one is the best? And what are all the reasons for choosing it?



    Paolo Stefano Crovetti · Politecnico di Torino

    Generally speaking, the choice of absolute resistors values for the feedback network of an opamp should be traded off considering different aspects: low resistance values give rise to improved performance in terms of DC accuracy (expecially when input bias currents are not negligible), lower noise, reduced impact of parasitics (e.g. the impact of 1pF parasitic capacitance in parallel to a 100Ohm resistor is negligible up to more than 1GHz, while the impact of the same 1pF parasitic in parallel to a 1MOhm resistor could be relevant at less than 200kHz), and hence better high-frequency behavior. Moreover in integrated designs, low resistance values also mean reduced area occupancy.

    On the other hand, a reduced resistance values mean an increased power consumption and additional loading effect on the output (as a matter of fact, the feedback network is connected in parallel of the actual "load" and wastes part of the opamp output stage driving capability). Unless there are valid motivations to do otherwise, it is recommended that the current flowing through the feedback network is negligible (say less than 5%) with respect to the current flowing through the intended load.

    The above considerations apply to any opamp-based circuit in any resistive feedback configuration.

    Considering the specific case of the "inverting opamp" circuit, a more critical point needs to be observed. The "inverting amplifier", unlike the "non-inverting" opamp-based amplifier is not a "true" voltage amplifier, since its input impedance is not (ideally) infinite, but is given by R1. As a consequence, the value that you choose for R1 is also the input impedance of the amplifier! If you expect that the cicuit behaves like an "inverting voltage amplifier", this input impedance needs to be significantly larger than the internal resistance of the source providing the input signal. Otherwise, input loading effect could be relevant.

  • Mohamed Hanafy added an answer in Wound Healing:
    Are there reliable biochemical markers of wound healing?

    Are there reliable laboratory markers of wound healing, that can be used to assess to what extent healing process occurs at different situation

    Mohamed Hanafy · Najran University

    Thanks Juthaporn for your comment, You mean that Inflammatory cytokines can be used as a marker for assessment of inflammatory phase of wound healing. & Growth factors for proliferative phase but  the question still remaining : which one of the mentioned biomarkers is more practically reliable for each phase ???

  • Farhan Ahmad added an answer in M2M:
    Can anyone provide me with a case study about the impact of the number of M2M device on the load of an LTE eNodeB ?

    The problems of overloading the network operator may occur and cause a decrease in performance for traditional EU network.

    Among the causes of overload and congestion due to M2M include:

    • From M2M applications transmitting repeatedly and synchronized data, precise time intervals (eg, each time)

    • A request for release from an M2M server requesting a large number of M2M devices to attach and establish a PDP context all simultaneously, eg, large number of counters becoming active at the same time after a power outage.

    • A large number of sensors transmit their data simultaneously following an incident, eg, monitoring threshold reached (level of rainfall magnitude of an earthquake, temperature level, etc.).

    • A malfunction at the M2M server can lead M2M devices that transmit their data to continue to transmit as long as they have not received acknowledgment of the M2M server. Similarly, if the M2M device that has a bad behavior, it may be necessary to continually send the same traffic.

    • A very large number of M2M devices lose network coverage due to a problem on a base station; these devices will simultaneously change all network must support a large number of requests simultaneously attachment and can also be establishing PDP contexts. Indeed, if the M2M network operator has roaming agreements with operators in the country where the client is, the M2M device can attach to any mobile operator depending on the signals received.

    The main causes of congestion above allow us to identify the risk of network congestion are mainly in the access control LTE network.

    I am seeking to characterize the impact of the number of M2M device on the load of one or more LTE eNodeB in different case studies such as those proposed above.

    Farhan Ahmad · University of Derby

    Please have a look on my publications: 

    1) https://files.nyu.edu/yz48/public/Final_LDIC_Farhan.pdf

    2) https://files.nyu.edu/yz48/public/Farhan_WTC.pdf

  • Can someone help me regarding association rule mining from XML data?

    I want XML dataset(Supermarket data are more preferable) which can directly be given as input to algorithm for association rule mining.

    Pooja Jardosh · Charotar University of Science and Technology

    i do have Tab separated file,And i want it to convert in XML file...I didn't find Clementine as a good option because this conversion is a small part of my project.

    Look at the file i have attached and provide me solution if you are aware about.


  • Abdul Raheem added an answer in Chemical Analysis:
    How do you calculate fixed carbon in biomass?
    How do you calculate fixed carbon in biomass?
    Abdul Raheem · Putra University, Malaysia

    Thermogravimetric analyzer could me better way to determine FC.

  • How does one recognize volcanic ash beds in Palaeozoic sedimentary sequences?

    Explosive volcanic eruptions occurred throughout Palaeozoic time.  Under the right set of circumastances they can be preserved in the sedimentary record.

    Paul C. Lyons · United States Geological Survey

    David, thank you for all the references.  My personal preference is electron microprobe microanalyis of glass inclusions because it gives you the pre-eruptive chemistry of the magma. Best wisihes, Paul.

  • Do you think that older people may benefit from phototherapy?

    Older people are often more exposed to artificial light because of mobility problems perhaps influencing mental states. For instance, lack of exposure to natural light might impact mental state.

    Do you think that older people may benefit from light treatment simulating expose to natural light conditions?

    Marcel M. Lambrechts · Centre d'Ecologie Fonctionnelle et Evolutive, Montpellier, France

    Phototherapy/Light therapy might be more important at higher latitudes during winter periods (short-day periods), but what if older people are forced to permanently stay indoors because of mobility problems?

    The assumption is that indoor light does not have the same quality and impact than natural light?

  • Has the role of values in architectural heritage conservation interventions been studied?

    I'm ready to cooperate and exchange information in this regard, I am working on
    a case study in the World Heritage TAKHT-E SOLEYMAN.

    Carlo Navato · Goldsmiths, University of London

    You might find this useful:


    In in general the English Heritage site is a fantastic resource for UK based heritage issues

  • Pravin kumar Patchaiappan asked a question in Annova:
    After one way annova tukeys or dunnet’t’ test which best?

    What is the correct post-hoc test (after one-way ANOVA) to test the effect of my drug in toxicity and efficacy study . which test i have do tukey or dunnet’t’ test

  • Veerendra K Rai asked a question in Exergy:
    The concept of exergy has been used in design of engineering systems? Has this concept ever been used in the design of socio-economic systems?

    Exergy is defined as the useful work available from an energy source. In other words exergy is energy available for use. This concept has been used in design of rocket systems. Can this concept of exergy be used in design and analysis of socio-economic systems? What are the possible equivalents of energy source in social systems?

  • Hakimeh Emamgholi added an answer in Asreml:
    What are the advantages and disadvantages between ASReml and DMU in animal breeding?

    At least I know DMU is free for use, but no more details I know about them. I only have experience in ASReml. Thank you so much.

    Hakimeh Emamgholi · Aarhus University

    You could find good examples of DMU following link: :http://www.vuzv.cz/sites/File/nabidka_publikace/pro_pdf_metodika_pribyl_2014_final.pdf

  • Navaneet Chaturvedi added an answer in Viral Genes:
    Can someone help me in designing a peptide which can be used as a candidate vaccine from a set of aligned sequences of human viral gene?

    I want to design peptide from group  a group of aligned sequences targeting a specific viral region of human. What will be my approach, I need step by step guide so that in each step I can overcome the hurdles through in silico approach. Further these candidate will be synthesized and will be tested in vivo in animal models.

    Thanking you.

    Navaneet Chaturvedi · Tel Aviv University

    Use Pymol or Coot for peptide design. Use builder tool in pymol to design peptides of your interest.

  • Behnaz Herbst asked a question in Metacognition:
    What kind of interventions or modifications can improve metacognitive calibration (judgment accuracy) in mathematics?

    I am researching high school math students' judgments of confidence JOCs of their capabilities, competence and preparedness. How can their calibration be accurately, and validly be measured?

  • Samaneh Karbalaei asked a question in Fish Toxicity:
    Why fish toxicity researchers use juvenile( immature) fish to measure toxic compounds?

    what is the relation of measure toxic compounds in fish before maturity?

  • Alfredo Pereira Junior added an answer in Qualia:
    How to define human consciousness?

    After many years of discussion of the concept of human consciousness, I arrived to the following definition:

    “Conscious processes are qualitative experiences that contain at least four kinds of ingredient:

    a) Sensations and feelings (such as hunger, thirst, happiness, sadness, fear, pain, pleasure);

    b) Perceptual qualities or ‘qualia’ (such as colors, sounds, smells, tastes, etc.);

    c) Cognitive processes grounded on feelings and ‘qualia’, such as attention, thinking, memory formation and recall, etc. and

    d) A spatiotemporal structure, composed of an egocentric spatial framework (according to the work of Arnold Trehub) and a temporal duration of (conscious) episodes of 100 milliseconds to 3 seconds (according to the work of Ernst Poppel)”.

    This definition does not include the controversial concepts of “Self” and “Free Will”.

    I basically agree with David Hume and Thomas Metzinger that the concept of Self is a product of conscious activity, not a metaphysical soul to be considered as a pre-requisite for the definition of consciousness. What is implied by the above definition is the existence of a body that is the bearer of experiences, and also is affected by them. In this sense, the definition is close to the phenomenology of Maurice Merleau-Ponty.

    The feeling of will is relevant for conscious activity, but the possibility - raised by Immanuel Kant - of initiating a totally new causal chain in the world, besides probably being an illusion, is not an essential ingredient of the concept of consciousness.

    The effect of conscious activity on the body (and vice-versa) cannot be explained in terms of Aristotelian “efficient causation” (since it violates the “causal closure” of the world, as pointed by Jaegwon Kim – see link below), but can be understood in terms of “formal causation”, in the sense that the form of body activity can affect the form of conscious activity, and the form of conscious activity can affect the form of body activity.

    Alfredo Pereira Junior · São Paulo State University

    Dear Claus, in your paper you state that consciousness is present in every physical interaction. This statement implies an assumption that any signal exchange between physical entities involves a degree of consciousness. Please justify how you derived this assumption from human conscious experiences. We do not have any conscious experiences of most signal exchanges that occur in our own bodies; e.g. we do not feel our DNA signaling to RNA and proteins; we do not feel the action of proteins in metabolism; not even the neuron action potentials that transmit information to our central nervous system or within this system; or the flow of blood in our arteries and veins, etc...In my tentative definition of consciousness based on phenomenology, I include only phenomena we are conscious of. I am not inclined to accept concepts of consciousness that include phenomena we are not conscious of. For instance, proponents of single cell consciousness state that every neuron has its own consciousness, but we are not conscious of them all.

  • Seyed Yahya Moradi added an answer in fMRI:
    What is the basic papers/data sets in Brain Function Analysis?

    Hi, I wanna start a new research for developing machine learning methods for Brain Function Analysis, especially for analyzing the cortex of Human Vision. Would you please help me to find some significant papers and fMRI data sets, which are related to mentioned subject? 

    Seyed Yahya Moradi · University of Isfahan


    Dear friend, 

    See This links. I hope be useful for you.

    Best Regard

  • Ángeles Pereira asked a question in Competitiveness:
    Is there any research on services to agriculture?

    I am interested in theoretical frameworks to understand why services to agriculture are increasing and what role services play in improving the competitiveness of small farmers.

    I look to different types of services: operational services (machinery,..) and also knowledge-based services (advice, extension...).

  • Petri Lankoski added an answer in Morris Water Maze:
    Can someone suggest easy tools to create a 3D computer environment for behavioural experiments?

    I am interested in implementing a virtual Morris water maze task for humans in our lab during intracranial recordings. Therefore, I would need a software that allows me to create 3D levels or environments and an output of the virtual position during spatial navigation. Is there any research oriented package for this purpose? 

    Important note: I am not interested in Oculus Rift kind of virtual reality, but simple 3D First Person Shooter like programs.

    Petri Lankoski · Södertörn University

    Modding existing games with modding tools

    - Valve Hammer Editor 

    - Unreal Engine 3 Editor 

  • Does anyone have advice or want to collaborate on PhD-research involving the soil-less growing of food crops?

    My own expertise lies in textile-technology, mainly technical knit structures. I started my PhD this autumn (2014) at the London College of Fashion.

    The first part of the research focuses on water-vapour-harvesting utilizing textiles as substrate.

    For the second part, the growing of food crops in a soil-less aeroponic/wicken micro-environment, we would need the support from an expert in the field of plant-biology and/or agriculture.

    Kaladharan Edavilakathil Ponnan · Central Marine Fisheries Research Institute

    Hi Rockel, Culture of PUFA rich microalgae can be included in your research programme.  If your  Institution is  close to sea, mariculture of   macro algae  is another option.

  • Djamel Teguig added an answer in Spectrum Sensing:
    How do I calculate complexity of cyclosationary detection method for spectrum sensing in Cognitive Radio?

    Hi experts,

    Does any one know how to calculate complexity of cyclosationary detection method for spectrum sensing in Cognitive Radio?

    Djamel Teguig · Royal Military Academy

    Dear sir

    The complexity can be represented by the overall operation to be performed to implement cyclosationary detection (FFT size and matrix multiplication windowing....).

    Best regards

  • Somayeh Jamali added an answer in Cherry:
    Does somebody know what I need to do FRET?

    I already have the plasmids (GFP and Cherry are the reported genes) but I do not know how I am going to measure the signal and what kind of microscope I really need.

    It would be great if you guys could provide me some information.

    Thanks everybody for the help and suport.


    Somayeh Jamali · Technische Universität Kaiserslautern

    Hi Arturo,

    we do FRET measure with confocal microscope and TILL Photonics fluorescence microscope.

  • Mahfuz Judeh added an answer in Trust:
    Do you trust people easily?
    Are you too trustworthy?
    Mahfuz Judeh · Applied Science Private University

    This is my nature. I easily and innocently trust all people, and I assume good intention in others.

  • Siham Elimam asked a question in Organic Farming:
    What is the benifits of adding charcool to the compost ?

    organic farming

  • Mohammed Alaoui asked a question in Matrix:
    How to overcome the matrix effects by standard addition method ?

    One of ways to overcome matrix effects is standard, My question how to use this method for evaluate the matix effects 

  • Raji Sudha asked a question in Fullprof:
    How to use fullprof suit tool bar application for xrd study?javascript:

    for xrd study i have downloaded the fullprof tool bar. but i could not use it. because i have files in uxd extension. how to convert it to dat or exe extension. If there is any other software used for xrd please send me the details.

  • Kamesh Natarajan added an answer in Biofertilizers:
    Is water hyacinth a good bioresource?

    Water hyacinth...biofertilizer

    Kamesh Natarajan · Bannari Amman Institute of Technology

    Of course, Water Hyacinth has well known bioresource. It have an capability for storing chromium ions in ponds.