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  • Andrew Johnson added an answer in Plagiarism Detection:
    Does anyone know a free plagiarism detection software I can use for a PhD thesis?
    see above
    Andrew Johnson

    @Atifi This service checks PDF's, PPT, .doc/.docx https://www.writemypaper.net/free-plagiarism-checker-for-students-online/

  • Aqib Javed asked a question in C#:
    Why we need c# programming what is purpoose of creating a new language what it new in it?

    we  have also object oriented programming and java then why we create a c sharp programming.

  • R. Abo-zeid added an answer in Difference Equations:
    Which are you preferring to do : Qualitative studies for a difference equation without getting the exact solution or getting the exact solution ?

    Which are you preferring to do : Qualitative studies for a difference equation without get the exact solution or getting the exact solution and then doing the analysis ?

  • Andrew Johnson added an answer in Plagiarism Detection:
    Is there any free plagiarism detection software?

    I am searching a plagiarism software for my students. The software named ithenticate/grammarly is excellent to detect plagiarism. However,  those are too expensive to afford to students.

    Any suggestion is appreciated on this issue?



    Andrew Johnson

    I agree with Artur. I've used Viper as well as some others. The best one I have found is https://www.writemypaper.net/free-plagiarism-checker-for-students-online/

    Let me back up and explain why I shared this link -- this is free for unlimited plagiarism checks. I haven't found anything similar -- does anyone know of software that offers unlimited free checks? I'd love to test them out.

  • Alfredo Pereira Junior added an answer in Glial Biology:
    What are the main results relating astrocyte functions with conscious activity?

    Several lines of evidence have related astroglial function with conscious processes. I make a brief summary of the most interesting studies, many of them discussed in my previous publications (Pereira Jr. and Furlan, 2009; 2010; Pereira Jr, 2013; 2014). These results come from several independent respected laboratories. Schummers et al (2009), in a work carried on the M. Sur Lab in MIT, found that astrocytes in the visual cortex are more sensitive to external stimuli than neurons. Thrane et al. (2012) from the M.Nedergaard Lab in Rochester-USA found that astrocytes are more sensitive to three commonly used general anesthetics than neurons. Sfera et al. (2015) argue that conscious delirium derives from a combination of cholinergic inflammatory processes and astroglialfunction failure. A conference summary of empirical results indicating the involvement of glial cells in mental activities appeared in Douglas Fields et al. (2014).

    By means of the feedback on neurons, astrocyte information processing can have an effect on learning, memory and behavior (for a recent review, see Robertson, 2013).Takata et al. (2011) found that astrocytes mediate cholinergic neuromodulation into cortical plasticity.  Han et al. (2013) inserted human astrocytes in the mouse forebrain and found an improvement of cognitive performance. In this regard, Lee et al.(2014), from the T.Sejnowski Lab in the Salk Institute found that toxic deactivation of astroglial functions impairs recognition memory, a task that involves conscious recall and processing of novelty.

    Astrocytes also seem to be involved in the instantiation of emotional feelings and psychosomatic responses, as in the case of chronic pain (see Chen et al., 2012; 2014; Ji et al., 2013). As the mediation between neurons and blood is made by astrocytes through the blood-brain barrier, astrocytes constitute the effector part of the hypothalamus (Panatier et al., 2006; Gordon et al., 2009) and nucleus accumbens (Bull et al, 2014), controlling the release of neuropeptides and their effects on conscious mood and feelings(e.g. hunger.; see Yang et al., 2015; Wang et al., 2015)and their related somatic responses, as the up-regulation of stress-related proteins (Zhao et al., 2008). More recently,Orstroff et al. (2014) from the J. LeDoux Lab in New York University discovered that astroglial processes retract from synapses with neurons that mediate fear signaling in the amygdala, and Will et al. (2015) related the number of astrocytes in the hypothalamus with the experience-learned ability to reach male orgasm.


    Bull C, Freitas K, Zou S, Poland RS, Syed WA et al. (2014 Rat Nucleus Accumbens Core Astrocytes Modulate Reward and the Motivation to Self-Administer Ethanol after Abstinence. Neuropsychopharmacology (2014) 39: 2835–2845.

    Chen MJ, Kress B, Han X, Moll K, Peng W, Ji RR,Nedergaard M. Astrocytic CX43  hemichannels and gap junctions play a crucial role in development of chronic neuropathic pain following spinal cord injury. Glia60(11):1660-70.

    Chen G, Park CK, Xie RG, Berta T, Nedergaard M, Ji RR. (2014) Connexin-43 induces chemokine release from spinal cord astrocytes to maintain late-phase neuropathic  pain in mice. Brain137(Pt 8):2193-209.

    Douglas Fields R, Araque A, Johansen-Berg H, Lim S, Lynch G, Nave K,Nedergaard M, Perez R, Sejnowski T, Wake H. (2014) Glial Biology in Learning and Cognition. Neuroscientist. 20(5): 426–431.

    Fellin T, Pascual O, Gobbo S, Pozzan T, Haydon PG and Carmignoto G.
    (2004) Neuronal Synchrony Mediated by Astrocytic Glutamate Through
    Activation of Extrasynaptic NMDA Receptors. Neuron 43(5): 729-43.

    Gordon, G.R., Iremonger, K.J., Kantevari, S., Ellis-Davies, G.C., MacVicar, B.A., Bains, J.S. (2009) Astrocyte-mediated distributed plasticity at hypothalamic glutamate synapses. Neuron 64: 391–403.

    Han X, Chen M, Wang F, Windrem M, Wang S, Shanz S. et al. (2013) Forebrain engraftment by human glial progenitor cells enhances synaptic plasticity and learning in adult mice. Cell Stem Cell 12:342–53.

    Ji RR, Berta T, Nedergaard M. (2013) Glia and pain: is chronic pain a gliopathy? Pain 154 Suppl 1:S10-28.

    Lee HS, Ghetti A, Pinto-Duarte A, Wang X, Dziewczapolski G, Galimi F, Huitron-Resendiz S, Piña-Crespo JC, Roberts AJ, Verma IM, Sejnowski TJ, HeinemannSF (2014) Astrocytes contribute to gamma oscillations and recognition memory. ProcNatlAcadSci U S A111(32):E3343-52.

    Ostroff LE, Manzur MK, Cain CK, Ledoux JE. (2014) Synapses lacking astrocyte appear in the amygdala during consolidation of Pavlovian threat conditioning. J Comp Neurol. 522(9):2152-63.

    Panatier, A. (2009) Glial cells:indispensable partners of hypothalamic magnocellularneurones.J.Neuroendocrinol. 21:665–672.

    Pereira Jr. A (2013) Triple-Aspect Monism: A Conceptual Framework for the Science of Human Consciousness. In A. Pereira Jr. & D. Lehmann (Eds.)The Unity of Mind, Brain and World: Current Perspectives on a Science of Consciousness (pp. 299-337). Cambridge, UK: Cambridge University Press.

    Pereira Jr. A (2014) Triple-Aspect Monism: Physiological, mental unconscious and conscious aspects of brain activity. Jnl. Integr.Neurosci., 13(2), 201-227.

    Pereira, A. Jr., &Furlan, F.A. (2009) On the role of synchrony for neuron-astrocyte interactionsand perceptual conscious processing. J. Biol. Phys.35 , 465– 481.

    Pereira, A. Jr., &Furlan, F.A. (2010) Astrocytes and human cognition: Modeling informationintegration and modulation of neuronal activity. Prog.Neurobiol. , 92 , 405– 420.

    Pereira, A. Jr., Barros, R.F. & Santos, R.P. (2013) The calcium wave model of the perception-action cycle: Evidence from semantic relevance in memory experiments. Front. Psychol. 4: 1–-4.

    Robertson JM. (2013) Astrocyte domains and the three-dimensional and seamless expression of consciousness and explicit memories. Med Hypotheses 81(6):1017-24.

    Schummers,J,Yu, H and Sur, M (2008) Tuned responses of astrocytes and their influence on hemodynamic signals in the visual cortex. Science 320: 1638–1643.

    Sfera, A, Osorio, C, Price, AI, Gradini, R and Cummings, M (2015) Delirium from the gliocentric perspective. Frontiers in Cellular Neuroscience 9: 171.

    Takata, N., Mishima, T., Hisatsune, C., Nagai, T., Ebisui, E., Mikoshiba, K., Hirase, H. (2011) Astrocyte calcium signaling transforms cholinergic modulation to cortical plasticity in vivo.J. Neurosci. 31(49), 18155–18165.

    Thrane, AS, Thrane VR, Zeppenfeld D, Lou N, Xu Q, Nagelhus EA & Nedergaard, M. (2012) General anesthesia selectively disrupts astrocyte calcium signaling in the awakemouse cortex. Proc. Natl. Acad. Sci. USA, 109, 18974–18979.

    Wang, F. Smith, N.A., Xu, Q., Fujita, T., Baba, A., Matsuda, T., Takano, T., Bekar, L. &Nedergaard, M. (2012) Astrocytes modulate neural network activity by Ca2+-dependent uptake of extracellular K+. Sci Signal., 5, 26.

    Wang Y, Hsuchou H, He Y, Kastin AJ, Pan W (2015) Role of Astrocytes in Leptin Signaling.J MolNeurosci. [Epub ahead of print]

    Will RG, Nutsch VL, Turner JM, Hattori T, Tobiansky DJ, DominguezJM(2015).Astrocytes in the medial preoptic area modulate ejaculation latency in an experience-dependent fashion.BehavNeurosci. 129(1):68-73.

    Yang L, Qi Y and Yang Y (2015).Astrocytes Control Food Intake by Inhibiting AGRP Neuron Activity via Adenosine A1 Receptors.Cell Rep. 11(5):798-807.

    Zhao Y, Xiao J, Ueda M, Wang Y, Hines M, Nowak TS Jr, LeDoux MS. (2008) Glial elements contribute to stress-induced torsinA expression in the CNS and peripheral nervous system. Neuroscience 155(2):439-53.

    Alfredo Pereira Junior

    Dear Brigitte, many thanks for your constructive comments! 

    You wrote: 

    "James Oschman writes about the spacing of collagen fribrils building a "crystal-like lattice which has the same right-handedness in both eyes and is thus bilaterally asymmetrical." (p.2 of the article). ...enabling both eyes to "accomodate to light moving vortically in the same right-handed path".... I believe that astrocytes are made up to a large degreee of collagen-like fibrils, aren't they? Therefore one of the main characteristics that would relate astrocyte functions with conscious activity must be the semiconducting structure of collagen with its hydration shell."

    Alfredo: I tend to agree with you. My friend Vera Maura Fernandes de Lima is an expert on the retina; we recently wrote a paper together (submitted). Please take a look at her RG page to find some of her publications. She is the person who told me about Pollack's theories of structured water. I am trying to figure out how the relation between polarized water (resulting in a kind of collagen, gel or crystalline arrangement - I am not sure what is the best term), calcium ions and proteins could be. For instance, Pollack's "exclusion zone" must have an effect on calcium concentrations in astrocytes. Hydrophilic and hydrophobic sites of proteins too. The complex interactions of ions, water and proteins is probably the central mechanism that makes life and consciousness possible. 

  • Dejenie A. Lakew added an answer in Cultural Studies:
    Writing a book on other cultures - what is the biggest challenge? How to overcome it?

    There are many approaches on how to write about other cultures and times. What is your experience on the biggest mistakes you saw? What would you recommend to avoid them?

    Is there some implication for nowadays cultural Exchange and reception of migrants?

    Dejenie A. Lakew

    Dear all,

    Culture is a long standing common social behavior of a particular society with apparent and hidden dimensions. To write a book about a culture of societies, it requires  to have either passion or authentic reason to know about that culture. Then if one has either passion or reason, then learn to speak at least the language and be able to acquaint self with the society to feel and read the essence of the culture from different strata (for knowing hidden and apparent or visible dimensions) which leads to do authentic research of depth about it. Then on the final writing process, truthfulness and honesty are vital where readers of the book demand. It is similar to writing a scientific paper on a topic. 

  • Robert James McClelland added an answer in Likert Scale:
    How can I make a correlation (Pearson) using a Likert Scale?

    Is it possible to make a correlation (Pearson) using a Likert Scale in a questionnaire with answers such:

    • Strongly agree
    • Agree
    • Neither agree nor disagree
    • Disagree
    • Strongly disagree
    • That's not apply to may case


    Robert James McClelland

    If the following criteria are met it is quite common to apply correlation testing.

    1. `is/are the agreement questions part of of set of validated scales? Should be yes.

    2. Code the option 'That does not apply to my case' as missing as this option should not contribute to a mean/any calculation. Use a 5 or 7 point validated scale

    3. The scale should be normally distributed, especially if to be used as a dependent variable (in for example regression)

    4. The scale should have an acceptable/reliable cronbach's alpha (>= 0.7)

    5. The variable to be correlated against this should obey the same criteria.

    Note: in a simple bivariate correlation the variables can be interdependent

  • Karissa Sanbonmatsu added an answer in Microarray:
    Any suggestions for long non-coding databases?

    I use Enrichr to investigate the relationships between coding genes from my microarray data. I was wondering whether there is a data base that I can upload my list of lcns and get a similar output. I can only see databases that require one-by-one searching. I have 100 hits so that will be time consuming! Thanks

    Karissa Sanbonmatsu

    lncrnadb.org is a great site. This gives the characteristics of the RNA and related references. 

  • Ola Norrman Eriksson asked a question in Biogas:
    Can anyone explain the definitions of following terms used when measuring methane potential?

    BMP - Biological Methane Potential

    HBT - Hohenheim Biogas yield Test (?)

    Biogas potential:

    Biogas yield:

    Biogas production:

    Specific yield:

    Cumulative yield

    Total yield

    Experimental papers are neither clear nor consistent regarding this!

  • Ramiro restrepo u added an answer in Rationality:
    How do the economists define self-interest and rationality?

    How do the economists define self-interest and rationality so as to make these concepts different from the animal instincts, beast behaviour, and barbarism? What is that which forms and what is that which does not form the self-interest? Moreover, are these the behavioural guides for all individuals? Are these the collective guides for policy making? 

    Given the propensity for free riding in each economic-beast, does not the collective policy results into a collective free riding of those who make policies over those who do not?

    Ramiro restrepo u

    Es claro que la "ciencia económica" tal como está formulada por el principio de "racionalidad ecómica" y la competencia perfecta, está en crisis desde sus fundamentos. La economía dominante no da cuenta de la realidad económica: crisis, mercados imperfectos, participación del Estado, tecnología endógene, desquiibrios, concentración de la riqueza y el ingreso, desempleo involuntario...Es preciso, por lo tanto, tal como lo propone Steve Keen (Debunking Economic) reformular la Economía desde una perspectiva como las clases sociale (como lo hicieron los economistas clásicos) : una macroeconomía que no necesite para nada de microfundamentos.
    It is clear that the "economics" as formulated by the principle of "ecómica rationality" and perfect competition, is in crisis since its foundation. Mainstream economics does not account for the economic reality: crisis, imperfect markets, state participation, endogène technology, desquiibrios, concentration of wealth and income, involuntary unemployment ... It is necessary, therefore, as proposed by Steve Keen (Debunking Economic) reformulate the economy from a perspective as sociale classes (as did the classical economists) do not need a macroeconomy for nothing microfoundations.
    ¿No es correcto?

  • H S Abdulrahman added an answer in Pavement Design:
    What are the factors that can influence the surface deflection of pavement?

    Please kindly help me regarding this issue, especially for flexible pavement. If it is possible, help me also with the references.

    H S Abdulrahman

    Slurry setting time is dependent on the environmental condition. Slow setting time usually it takes longer time to cure and break. Generally for cold weather rapid setting will be encouraged because it takes longer time to cure and break especially at  night.

  • Staffan - Jacobson added an answer in Wear:
    What is the type of wear when we do a wear testing for a cylinder head valve?Is it abrasive wear or fatigue wear? can anyone explain about this?

    there is a lot of types of wear include abrasive wear, catastropic wear, corrosive wear, fatigue wear, cutting wear, impact wear and so on. my experiment is to test a wear on a cylinder head valve but I'm not sure what type of wear it is because there is quite similar between some of them. 

    Staffan - Jacobson

    Dear Syazwan, 

    I am afraid that the wear process is too complicated to be described by a single mechanism. The contact involves high loads at repeated contact, at high temperatures, and without any conventional lubrication. At each closing of the valve there is a relative hard impact plus a limited sliding. The wear can also differ between intake and exhaust valves in the same cylinder. 

    The wear rate depend also on the type of fuel that is used, and the amount of oil (including its additives) that is combusted. It has been shown that microscopic ash particles following flowing through the exhaust valve may become trapped on the sealing surfaces, becoming worked by the operating valve and eventually forming protective tribofilms, a couple of µm thick, or so.

    May I recommend you to read the freely downloadable thesis of Peter Forsberg, If you want to know more on this demanding subject. The thesis also give reference to further papers. Link to download the thesis:

  • Ramin Farajpour added an answer in Fixed Cell:
    Is it possible to reversibly permeabilise nuclear membrane in fixed cells?

    I need to deliver a substance to the fixed cell nuclei and then possibly prevent the substance from escape. I tried so far a bit with Saponin but with no major success.

    Thanks in advance for replies.


    Ramin Farajpour

    Thanks a lot for your good question. I suggest you follow the attached link below to find an appropriate article for your question. 

  • Muhammad Khattab added an answer in UV-Visible Spectroscopy:
    3D excitation, emission and excitation-emission experiments?

    I am wondering what is the importance and how to interpret these experiments. Also, i noticed that i can't have background corrected (No blank subtraction) for these experiments using perkin elmer equipment. How to solve this problem?!!!! Besides, I appreciate if you could send me some resources to read about 3D experiments.

    Thanks in advance, 


    Muhammad Khattab

    Thanks all very much!

  • Rebecca Lloyd added an answer in Mixed Methods:
    What is the magic number for a survey response in a Mixed Methods Triangulation?

    My study has in depth qualitative semi structured rich interviews which I am coding using Phenomenology. I am 'triangulating' with a survey.
    All my research is based in Inner City Limerick, so the sample size is already small and I have a high take up. From the 28 solicitors I have 18 completed surveys. Is this enough? Can anyone point me to a similar study?

    Your guidance is much appreciated to this novice researcher

    Rebecca Lloyd

    Is it though? If you are using different populations?

  • N. Rishiraj added an answer in Anterior Cruciate Ligament:
    Can someone help me? What kind of neuromuscular training is the best way to prevent ACL injuries?

    I have read several articles but it is not clear what kind of training is best for the prevention of ACL injuries. 

    N. Rishiraj

    Thanks for your feedback Dr. Zafiropoulos. What you state is correct these are exercises used by many athletes to prepare for elite competition and as some publications have suggested as part of ACL prevention protocol.

    However, as stated by the  Dr. García, ("... best way to prevent ACL injuries?") do these exercises prevent ACL injuries?  If so, by what mechanism(s)?

  • Priit Võhandu added an answer in Outliers:
    Which is the best method for removing outliers in a data set?

    In statistically analyzing a data set, suppose we have to found some of the outliers, if necessary to remove them which method is appropriate?

    Priit Võhandu

    I assume that you have the method how to detect outliers. For removal a simple and  good approach is to delete them. If you try to replace them with mean, median or something else you can easily create a bias. And if you are into the KDD it is not much use to discover what bias did you create yourself.

    If the data set after deleting outliers still forms a representative sample you can carry out your planned analysis.

  • Andrew David Lyle Nelson added an answer in Endonucleases:
    Could any type of nuclease be biased for 12C-DNA versus 13C-DNA?

    If so, how much bias do you think is possible?

    Andrew David Lyle Nelson

    Hi Nicholas,

    This is an interesting question. I assume by 13C you are talking about the radioactive isotope? If so, I can't imagine that an extra neutron would have any kind of effect on the cleavage of the phosphodiester bonds. But, this sounds like the expertise of a hardcore biochemist would be required. I would say no though (for what it's worth).

  • Francis David Tingley added an answer in Oxytocin:
    Can anyone recommend a reliable ELISA kit for rat neuropetide Y, oxytocin and vasopressin?

    Assay in brain and plasma samples

    Francis David Tingley

    It was a long time ago, I do not recall. It may have been both but at least plasma. Please check out the online protocols for these assays. They will list the viable sample types.

  • Anand Dev Gupta added an answer in Air Pollution Modeling:
    Any tips on traffic air pollution modeling?

    I have much data about traffic air pollution. i want to apply some models in it. can some one suggest about it?

    Model name?


    Software (if necessary)

    any else?

    because i have no clue about it.

    Anand Dev Gupta

    Thank you francesco Pilla sir.

    i will try it.

  • Pedro Moreno Garcia asked a question in Markets:
    Market penetration strategy for a saturated market?

    How do I measure a market to tell it is saturated and if it is, how could I penetrate into the market? Im specifically trying to go into the US Market

  • Parisa Heidarnejad added an answer in Thermodynamic Modeling:
    How can I model a cycle including ethanol amine through EES, while it does not have thermodynamic properties of ethanol amine?

    Mono Ethanol Amine (MEA)

    Parisa Heidarnejad

    I want to to carry out thermodynamic analysis of Carbon Capture and Storage system including amine scrubbing.

  • Robert James McClelland added an answer in Questionnaire Design:
    Writing research proposal for injuries in skaters will be validating the Questionnaire after pilot study. How do I get my Statistical Power?

    Study will be done on inline skaters to be conducted in India. Questionnaire will be validated after pilot study. How do I explain the Statistical Power for the study before and after pilot study?

    Robert James McClelland

    Numerous programs are available for performing power and sample size calculations:

    Webpower is a very useful site for this:


    This site also has many easy to access calculators:


  • Rogier Brussee added an answer in Real Functions:
    Suppose f(x) is negative and increasing whiles g(x) is positive and decreasing. Can we conclude that the product f(x)g(x) is decreasing?

    Let f(x) and g(x) be real functions defined for x>0 such that f is negative and increasing, whiles g is positive and decreasing. Can we conclude that the product f(x)g(x) is decreasing? or What condition(s) will make this product decreasing? Your comments will be appreciated.

    Thank you.

    Rogier Brussee

    The product fg is always increasing,  you don't have to make any assumptions on the regularity of f and g, in particular you don't have to assume that f and g are differentiable

    Suppose x > y then by assumption, f(x) > f(y) and f(x), f(y) < 0, while g(x) < g(y) and g(x), g(y) > 0. Hence

    f(x)g(x)  - f(y)g(y) = f(x)g(x) - f(x)g(y) + f(x)g(y) - f(y)g(y)
                              = f(x)(g(x) - g(y))  + g(y)(f(x) - f(y)) > 0

    because each of the two terms is positive.

  • Mohand Said Kachi added an answer in Concrete:
    What is the shear capacity of reinforced circular concrete section?

    How can I evaluate the shear capacity of reinforced circular concrete sections by hand calculation? Do we have to consider the impact on shear distribution due to presence of rebars?  Thanks

    Mohand Said Kachi

    You can read my paper intitled shear in the medeling of the reinforced concrete.

    "1.        Kachi M S ; Muller P, Bouafia Y, FOURE B. L’effort tranchant dans la modélisation du comportement jusqu’à rupture des poutres armées. Revue européenne de génie civil N° 10/10 Décembre 2006." You found some of idea for calculation of the shear capacity of sections.

  • Zeljko Stojanov added an answer in Grounded Theory:
    What is an analytical framework?

    In qualitative research, particularly in interpretative research tradition, researchers have been paying attention towards developing new analytical frameworks to guide their data generation techniques and its analysis. It seems to me that those who adopt inductive research approach (or mixed of both deductive and inductive) approach need to develop an analytical framework.

    I am expecting some expert opinions/experiences of developing analytical framework for qualitative research. Answers could be framed around the following questions:

    a. Why do qualitative researchers require to have analytical framework?

    b. What are the procedures to develop an analytical framework? (why do not existing frameworks always fit into research?)

    c. In ground-theory approach, to what extent does the influence of deductive approach remain dominant whilst developing a new analytical framework?

    d. Any good source materials?

    Zeljko Stojanov

    Qualitative research is situated in a specific context, which requires a flexible researcher ready to adapt research design to the circumstances. Several prominent researchers suggested to adopt flexible research design, which can lead towards developing specific analytical framework. It is advisable to read about possible approaches, documented in the literature, adopt and play with some of them. However, we always should have in our minds that we must understand what is going on.

    Developing an analytical framework is challenging, especially if you can apply it in few cases to check how it works. And of course, the framework may evolve based on the experience from the field.

    Good luck and enjoy in experimenting.

  • Fatih Yalçın asked a question in Entrepreneurship:
    How can I connect "Strategic HR" and "Entrepreneurship" in a theoretical sense?

    I need a topic to study for my term paper.

  • Cihan Cengiz added an answer in Soil Mechanics:
    How do I calculate shear strains using acceleration-time records at same depth?


    I'm working on equivalent linear analysis in soils and re-write it.

    Now i have some problems with computing the shear strains.

    how could i calculate the shear strains using acceleration-time records in specific depth ?

    I thing in first step must convert acceleration-time to displacement-time, But i don't know what would be the next steps ?

    Could you please explain it to me?

    Thank you.

    Cihan Cengiz

    If you have a finite elements mesh or any other point system where you can quantify the accelerations, you could make integrations to get displacement time data. 

    From there on you could calculate the shear strains by making use of the angular distortions between the points, I guess. 

  • Erini Abdelmessih added an answer in Grounded Theory:
    What is the most appropriate qualitative approach?

    In my qualitative study I will ask ethnic patients regarding their health care preferences and needs so to manage their disease. Then,  I will ask them to validate a proposed patient-centred care model based on their preferences and needs. I read extensively, and not sure whether phenomenology would suit (given that patient perspective is sought) or would it have to be grounded theory given that I am developing a patient centered care model for a certain patient group? Thanks 

    Erini Abdelmessih

    Thank you for that Gordon. 


  • Vidhura Mahendra added an answer in Polyethylene Terephthalates:
    Which one is the best method to recycle the waste polyethylene terephthalate (PET) ? Thermal cracking (pyrolysis) or chemical depolymerisation?

    Pyrolysis is a thermochemical decomposition of organic material at elevated temperatures in the absence of oxygen (or any halogen). It involves the simultaneous change of chemical composition and physical phase, and is irreversible.

    Vidhura Mahendra

    Hi Chung,

    Nitrogen is an inert gas and has the potential to dry the environment in other words to make free of oxygen so the components will not be oxidized during the reaction period.

    Thermal cracking in common is the break down of long chain hydrocarbon molecules to smaller molecular weight. Hydrolysis is breaking down with a reaction of water.

    It really depends which one is cost benefit for your requirement or application :)