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  • R. Maheswar added an answer in Qualnet:
    QualNet or MATLAB which one is better for Wireless sensor networks?

    Wireless sensor networks are used for applications of smart grid environment.

    How can we obtain QualNET. 

    R. Maheswar · Sri Krishna College of Technology

    Qualnet will be the best

  • Carmen Camilleri added an answer in OHSAS 18001:
    How do you define nonconformity?

    Every safety management system needs a process for dealing with OH&S non-conformities and for taking corrective action, but how do you define ‘nonconformity’ in your system?  “The non-fulfillment of a requirement”, as nonconformity is defined OHSAS18001, seems extremely broad and liable to over-burden the best of processes.

    BS OHSAS 18001:2007 says: 3.11 nonconformity = non-fulfilment of a requirement  [ISO 9000:2005, 3.6.2; ISO 14001, 3.15]
    NOTE A nonconformity can be any deviation from:
    • relevant work standards, practices, procedures, legal
    requirements, etc.

    Carmen Camilleri · University of Malta

    Dear Roland,

    In nursing care we refer to the term 'nonconformity' when the patient /client does not agree with the treatment/medication/procedure prescribed to him/her and tends to do whatever s/he wants, even after adequate information and education were given by the doctor and supported by the nurses.


    Carmen Camilleri

  • Marc Tessera added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.


    Why do you think Dehaene declined the invitation to participate to your Nature Online invited conference on consciousness?

  • How different is the vibration analysis of nano beams from macroscopic beams?

    I am doing a vibration modeling of nano beams, where I need to introduce the theory of non local elasticity in order to generate the nonlinear governing equations.

    Amir Mehdi Dehrouyeh-Semnani · University of Tehran

    If you want to derive governing equations of a nano beam and analyze vibration characteristics of it (for both linear or nonlinear models) based on nonlocal theory,  the internal length scale must be comparable with size of the nano beam.  (if the ratio of thickness to length scale is more than 10, the influence of nonlocal terms have no considerable effect on the solutions.)

  • What is the difference between a base learner and meta learner in ensemble learning?

    In weka, when i tried to implement ensemble learning methods, it is asking to choose a base learner. What does the base learner and meta learner do ?

  • Effects of alumina in iron ore
    What are the disadvantages and advantages?
    Himansu Shekhar Mahapatra · JSW Steel Ltd.

    it depends. can u specify the area where u want to directly use the specified iron ore .

  • What are the advantages and disadvantages of high silica in iron ore?

    If the ore is of less Alumina and High Silica what is the effect of it in the iron making?

    Himansu Shekhar Mahapatra · JSW Steel Ltd.

    Hi- Silica Iron ore fines are very useful for sinter making, as they are used to dilute lower silica iron ore during blending and resulting to the desired sinter chemistry.

  • Martin Laporte added an answer in Molecular Ecology:
    Using Structure: is it correct to test K values which exceed the specified number of sampling locations for admixture-locprior model?

    Using admixture model as is, we have enough strong signal for some individuals from each locality and weak signal for others. And we want to use admixture-locprior algorithm to test may these individuals belong to known populations, too, or they may originate from additional populations located outside of the all locations in studied area.
    Thank you.

    Martin Laporte · Laval University

    You can always try K= higher than the number of group. However, I will also suggest to run your data without prior information on your location.

  • What is the influence of the day care centres on the parental involvement during the early childhood?

    There are different types of day care centres formal and informal, but of which all require parents to be involved in their children upbringing. But how does this influence the parents/ caregivers' involvement from ages of 0-5 years?

    Carmen Camilleri · University of Malta

    Dear Mahlalele,

    I think that from 0-5 it is essential to have good bonding with the parents and so day care centres need to look at the aspect of involving parents as it is essential for the child's development.


    Carmen Camilleri

  • Victor Cojocaru added an answer in Microemulsions:
    Should the transparent gel-like structures obtained for water-oil-(surfactant+cosurfactant) systems be considered microemulsions?

    For microemulsions formulated using alcohols with the hydrocarbonate chain of medium length (i.e. 1-hexanol, 1-heptanol, 1-octanol), at a certain point (i.e. certain water concentration), the system viscosity has a sharp increase and a transparent, clear gel is formed. Can this be considered a microemulsion? Do you have any idea if it is birefringent or not? By any chance, are there articles on the subject of ternary phase diagrams for systems containing these alcohols as cosurfactants? Thank you.

    Victor Cojocaru · Carol Davila University of Medicine and Pharmacy

  • Tarik Ömer Oğurtani added an answer in Cells:
    Will lattice constants be different in the case of supercell of any unit cell ?

    If somebody is working on supercell and wants to report lattice constants. Do they need to report lattice constants of supercell or unit cell. For example supercell of 3*2*1, if the lattice constants a, b, c are  divided by 3, 2, 1 respectively then it will be equivalent to lattice constants of pure unit cell. Should the lattice constants from unit cell and its supercell  be same or different?

    Tarik Ömer Oğurtani · Middle East Technical University

    Dear Gert  probably i am looking to this problem from the eyes of physical a physical metallurgist while he is dealing with the order- disorder transitions and their products. Take CuZn ordered structure where Cu occupies cube corners and Zn occupies cube centers therefore the structure has CsCl Bravais lattice that means it is simple cubic lattice/ Therefore one observes the  complete set of spectral  of lines  belong to SC . On the other hand in the case of complete disordered systems cube  corners and body centers are occupied randomly by Cu and Zn atoms therefore now we are facing the BCC Bravais lattice where   h and  k unmixed and  sum over h,k, l  even are observable reflections the rest are not.  The extra observed lines between these two spectrum  are called superlattice lines,  which are indications of the existence of the ordered structure.

    In other words  h and k mixed and  h + k + l  Odd  are superlattice lines for the present case.  Their intensities  increase with  difference between fCu and f Zn atomic scattering factors/  The extend of the ordered columns of  CuZn\ which are in reality constitute  regions \ which are  separated by domain walls or by antidomain walls  from their  neighbors/   The sharp superlattice line observed as long as order persist over lattice region of about  1 micron, large enough to give coherent x=ray reflection/ When long range order is not complete the superlattice lines becomes broadened, that gives us the opportunity to obtained domain size/

    Therefore according to my opinion  if the supercell is defined by the extend of the ordered chain of  the highest symmetry producing Bravais unit cell /CsCl / as such that coherency is satisfied then it  may be OKAY.   But  still it is an  obscure quantity. 

    I think what you guys are calling supercell we call them domains in ordered structures/  Like the magnetic domains etc/  

  • Amr Al-Haidari added an answer in Tumors:
    Can anyone advise me about RIP-Chip with anti-miR in tumor cells?

    Hi All..

    I was wondering if you have an antimiR that has an effect on its correspoding miR.. would it be obvious to see this effect also in AGO2 complex in RIP-Chip? I got some enrichment of my miR in the treated cells with anti.miR!! is it supposed to be decreased in the AGO2-IP?

    replies are appreciated

    Amr Al-Haidari · Lund University

    thanks Pinchas.. 

    im using antagomiR yes. but there was an enrichment of miR. really getting me confused!

  • Azuama Onyedikachi asked a question in Emergence:
    Why did MERS emerge at this time and are their other coronaviruses waiting to emerge?

    Hi everyone i am writing about coronaviruses and are the questions i keep asking

  • Mahnaz Shahzamani asked a question in LaTeX:
    How can I lower the pH value of a commercial polymer latex?

    I would like to lower the pH value of a preformed latex and keep it constant at this value during the reaction.How it can be buffered?

  • Yue Li asked a question in MAXENT:
    When using MaxEnt, how can I test multicollinearity of environmental variable?

    Hi colleagues,

    I plan to use MaxEnt to estimate the potential distribution of a species.

    I downloaded 19 current bioclimatic variables of a regional grid from WorldClim and I have a set of occurrence data of this species (about 50 localities).  I think it had better exclude some correlated bioclimatic variables.

    Can anyone guide me how to test multicollinearity of environment variables?


  • Ravi Kant Upadhyay added an answer in Scale-up:
    What are the limitations in scaling up biotechnological processes in environment monitoring and Pollution Abatement?

    The several well established and novel biotechnologies are available to deal with environment control. Several aspects of their performance are still to be tested. 

    Ravi Kant Upadhyay · Deen Dayal Upadhyaya Gorakhpur University

    There are so many limitations of these technologies. First one can not find any data of pollutants and its effect in deep waters, black waters, wet land, bottom garbages/pollutants in sedimentary or particulate pollutants. Similarly, in space biotechnological approaches are failed to recollect and enumerate the horizontal and transverse mixing of pollutants. There is a limitation of altered environmental or eco-climatic conditions.   Effects of pollutants on physical and chemical environment is very hard to enumerate because many more modifications and expertise will be needed to find ESA. 

  • Nayera Abdelhafez added an answer in Building Codes:
    What is a good methodology for evaluating the impact of building code changes?

    For example, I'd like to see window sizes restricted to 40% of total wall area in temperate climates for commercial and multi unit residential buildings.  How would I measure its direct impact on energy consumption and be able to isolate it from other factors like more efficient appliances in new builds, smaller units, etc? 

    Nayera Abdelhafez · Egypt-Japan University of Science and Technology

    Simulation programs is the best  way for your case to fix all other factors and focus on window to wall ratio. you can use Design Builder or TRNSYS . both are good in calculating energy consumption. However, TRNSYS is more detailed in mechanics.  

  • How can I synchronize multiple voltage sources on single transmission line?

    Working on assignment to have one converter in which solar and wind turbine are connected as input source want to utilize both sources to have sufficient amount of voltage to utilize them on utility grid, how can I match the frequencies generations of both sources and mat with the frequency of utility grid?

    Krishnarayalu Movva · Velagapudi Ramakrishna Siddhartha Engineering College

    solar energy is converted to DC voltage. hence invert this into 50/60 Hz sinusoidal voltage. Then synchronize to the grid. Similarly wind energy also will not give pure sinusoidal voltages .Also induction generators work above synchronous speed.  so convert the wind generator output to DC then invert to AC. next synchronize with grid. 

  • Mustafa Kutlu added an answer in References:
    Any good references for predictive control?

    I am looking for reference about the theory and applications.

    Thank you!

    Mustafa Kutlu · University of Southampton

    Hi Suleiman,

    I believe Prof Jan Maciejowski is one of the best researchers in predictive control area-please find attached link.

    I hope it helps.


  • Arshad Khan added an answer in Fluorophore:
    Why the fluorophore has a larger dipole moment in the excited state?

    Can anyone tell me

    Arshad Khan · Southeast University (China)

    Thanks Fraooq 

  • David Bearg asked a question in Ventilation:
    How do find the best way to quantify displacement ventilation ?

    Performing tracer decay testing in non-well mixed spaces.

  • Mamdouh Alsayed Eissa asked a question in Halophytes:
    How the halophyte plant reduce water loss during the heat?

    I made a study to investigate the ionic contents and nutritive value of big saltbush (A. lentiformis) and old man saltbush (A. nummularia) during the different seasons of the year.

    I found some results needed to explanations:

    1- during high temperature conditions the plants tend to increase the Na, K and Cl in leaves, while under low temperature conditions they tend to minimize the concentration of that ions.

    2- during the high temperature conditions the phosphorus concentrations and water content were declined.

    3- the crude protein in the tested plants increased in low temperature and decreased in high temperature.

    I suggest that these plants increase their Na , K and Cl in heat condition and minimize water content to make osmotic adjustment to minimize the water loss during high temperature condition.

    If that correct can any one help me with some literature references?

  • Muhammad Ali asked a question in Infinity:
    Convergence of double series.?

    Can anyone recommend some book that discusses the convergence of double series?

    Is that following relation holds under certain conditions?


  • Melinda Moyo asked a question in Variability:
    What do we call a design that has one independent variable and two dependent variables?

    with regards to experimental designs

  • Björn L.D.M. Brücher added an answer in Dogs:
    Should we remember in the History of Gastric Surgery the following achievements?

    Today, 124 years ago, 1st successful distal gastrectomy by Theodor Billroth

    29th Jan 1881: Christian Albert Theodor Billroth Billroth (* 26. Apr 1829 in Bergen, Island of Rügen, Germany; † 6. Feb 1894 in Abbazia, Istria) performed the 1st successful distal gastric cancer resection, known as the Billroth-I-operation (B-I operation) in the 43y female patient Therese Heller, a mother of 8 children [Billroth 1881]. It was the 3rd reported try performing a distal gastric resection but the first successful one, these days known as the Billroth-I-operation. Therese Heller died 4 months later due to metastatic spread into the liver.

    Earlier, in 1879, the french surgeon Jules Émile Péan alias "The Pean" (* 29. Nov 1830 in Châteaudun; † 30. Jan 1898 in Paris) performed the 1st known and reported distal gastric cancer resection, but the patient died at the 4th postoperative day [Pean 1879].

    And in 1880, Nov 16th, the polish surgeon Ludwik Rydygier (* 1850 in Graudenz [= today Grudziądz]; † 25. Jun 1920 in Lemberg / Ukraine) had performed the 2nd but not successful distal gastric resection on a 63-year-old man named Julius Mickotajewicz who was known to have a duodenal ulcer, the patient died 12 hours later [RYDYGIER 1882]. A 2nd try at 21st Nov 1881 in a gastric ulcer patient was successful.

    The achievements above had been possible – despite of course due to the experimental work of Billroth’s pupil’s Czerny, von Mikulicz-Radecki, Woelfler and von Hacker - due to the detailed report of a medical student from Giessen, Germany, Daniel Karl Theordor Merrem [* 1790 in Duisburg, Germany; † 1859], who demonstrated the operation in three dogs, and two survived, in a dog.

    I would assume, we can learn a lot fom historic achievements not only in regard to technical surgical perspectives,

    Did you know that already these days, fast track - one of the newer hype man-made therapies in patient treatment was performed? Therese Heller received sour milk, starting "1 hour" after the operation, so maybe some surgeons start smiling as they recognize that the hype “fast track” had been already in use long time ago.

    However, Billroth performed 41 gastric resections until 1890 and only 19 had been successful, meaning less than 50%.

    Other achievements of Billroth had been:

    1870 1st successfull esophagectomy ina a dog
    1873 1st successfull laryngectomy in a human
    1874 discovery of the streptococcus

    PEAN, J. E. (1879), Gaz. Hop. (Paris), 52, 473.
    RYDYGIER, L. VON (1882), Berlin. klin. Wschr., 19, 39 and RYDYGIER, L. VON (1882), Zbl. Chir., 9, I98.
    BILLROTH T (1881), Ibid., 31, 162.
    BILLROTH T (1881): Offenes Schreiben an Herrn Dr. Wittelshofer. Wien Med Wochenschr;31:162-5.

    Björn L.D.M. Brücher · Theodor Billroth Academy

    Thanks Frederic

    ad 1 & 2 completely agree. It is always funny in a retrospective manner, that some declare ‘there wont be any progress’ or ‘this or that will be “solution” ….’. History teach us, that there are always different views and that we can learn from such

    ad 3: unfortunately that is true. Many achievements of the Eastern World even had not been published and by this it is nearly impossible receiving the correct information. And you are right: it is easier with Western Achievements.

    Did you know that William Stewart Halsted got the book of education written by Theodor Billroth after his traveling through Europe and by this transferred Billroth’s ideas into education at John Hopkins? Of course during the decades they had been tried attributing to Halsted, but originary had been Theodor Billroth’s ones. This may be one example how reality changes, if originary literature is not cited anymore.

  • What is the significance of serum starvation when studying molecular signalling pathways especially Insulin signalling?

    why do researchers serum starve the cells before studying the molecular event in a cell line. I am planning to look at the Insulin signalling events in skeletal muscle cell lines, should I serum starve them before stimulation with insulin?

  • How do you determine standard deviations for linewidth and integrals using NMR line shape analysis ?


    I am trying to estimate the standard deviation/error of the linewidth and the integral from a single spectrum. I would generally expect any fitting procedure to give me such estimates on fitted paramters. However, MestreNvoa, the program I am using, does not support this feature.



    Eike-Christian Wamhoff · Max Planck Institute of Colloids and Interfaces

    I have quite long experimental times per spectrum that's the reason I am tied to n =1. Yeah, you are right, I will probably miss random/systematic errors due to processing or experimental setup. So I thought I should at least account for the random errors due to the SNR in the spectrum.

    I am performing a lineshape analysis to obtain koff for a protein-ligand system.

    In the end, I exported the processed spectra to Origin and used a lorentzian lineshape fit. Works pretty well and the errors I obtain errors from the fitting procedure are definietly helpful to judge whether deviations in the lineshape analysis/affinity determination can be explained by the SNR.