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  • H.-P. Schulze added an answer in Electrical Discharge Machining:
    Which different methods are used for parametric optimization of EDM?

    Which different methods are used for parametric optimization of EDM? Which is the best suited?

    What is the advantages, limitations and difference between different methods of optimization of EDM like taguchi, regression analysis, genetic algorithm, gauss elimination, ANOVA etc...

    H.-P. Schulze

    This paper is unfortunately only in German.
    Computer-aided optimization of electro-erosive sinking process (EDM)
    by KH Laurent, M. Kunert and H.-P. Schulze
    Elektrie, Berlin 36 (1984) 6, page 205-209.
    see Publications Dr. H.-P. Schulze in RG.

  • David Mathuva added an answer in common accounting language:
    What is the necessity to have a common accounting language?

    Why was it so important to introduce the Ias/Ifrs princples? What are the reasons? Do you have some articles or any other help?

    David Mathuva

    ..Accounting is viewed as an art as well as a science. It is guided by standards with the aim of producing information that is relevant and comparable (being the FUNDAMENTAL qualitative characteristics of useful information). To achieve such objectives, we have to communicate using a standard way. Accounting permeates all nations, societies and the world over. To be able to compare a similar reporting entity in Sicily and Bermuda, we need to use a standard approach. You can imagine how the world would be like if every nation/society/polity/jurisdiction developed their own set of accounting standards. Nations have even realised the need to and harmonise the standards (except the U.S. and a few other nations who have lagged). This realisation is because, we are all speaking the same language: for every DEBIT, there has to be a corresponding CREDIT! So, sticking to your own standards with claims of 'superiority' of some set of GAAPs is a façade that may not stand the test of time. 

  • Elhaj A. Elsiddig added an answer in Multiple Regression Analysis:
    How do I minimize multicollinearity in multiple regression analysis?

    I conducted multiple regression analysis but I found multicollinearity which leaded to results against my literature. I advised to centering the variable ( X- Mean(X)) but unfortionately regression can not be conducted becuz all variables became constants

    Elhaj A. Elsiddig

    thanks all for your participations in question

  • Debashis Panda added an answer in Refrigeration & Air Conditioning:
    How do I mix nanoparticles directly with refrigerants in a vapour compression refrigeration system (I do not want through the lubricating oil)?

    I know the procedure mixing the nano particles with the refrigerants through the lubricating oil. I want to know the procedure to mix the nano particles directly with the refrigerants.

    Debashis Panda

    Dear Nithyanandhadhass, Mixing of nano particle always depends upon the the solvent density , what you used and size of the nano particle.

    So higher is the solvent density, better is the nano particle dispersion and smaller is the particle size of nano particle, decrease the effect of dispersion.

    So its depends upon the density of the refrigerant. best method is non-contact cavitation method for mixing.

  • Mark Han added an answer in Metamaterials:
    What are the most representative "practically useful" results from the research on acoustic meta materials?

    I have not seen a result from this research which can be practically useful. Those are all re-confirmation of the more hundred year old principle... Is there any rebuttal?

    Mark Han

    That is why I always feel embarrassed when people ask me what I can do with acousitc metamaterials. Perhaps we need do something to change this situation.

  • Amir Javad Ahmadian Hosseini added an answer in Turbulence:
    Which turbulence model is best to predict reattachment length of flow over a step?

    I have few questions if any one can add to it:

    1. I want to run a simulation with experiments done in free surface water tunnel. Which model you think can predict good reattachment length.

    2. I am using turbulent length scale 6mm and turbulent intensity of 5%. If the reattachment length is not close which parameter should i adjust.

    3. I am using 0 pressure gauge as outlet boundary condition. However experiment was conducted in close recirculating water tunnel. Is it correct? or should i use outflow as boundary conditions.


    Looking forward to hear from you soon.

    Amir Javad Ahmadian Hosseini

    Dear Hassan

    standard K Epsilon and standard K Omega models could help you to get good results. although Reynolds stress model (RSM) is a perfect one but it would increase your solution time. I attached you an ANSYS tutorial for simulating turbulence flow over an step. I hope it would help you.

    Good Luck

  • Anthony Nash asked a question in Zinc:
    How to generate a new starting structure in Gaussian?

    Hi all,

    Rather a simple request here. If I have a large molecule, say 55 to 70 atoms big, it is bound to have several energy minima. One example being, if this were a derivative of a sugar like glucose, there would be typically around two unique energy minima associated with a different orientation of the hydroxyl group. 

    I would like to collect as many converged minima as possible. Is there anyway to perturb the structure so it drives down to the nearest minimum? 

    A reason for doing this would be to collect as large a set of interatomic distances between certain atom e.g., if this were a zinc binding ligand, I would want to measure the distance between the zinc atom and the nitrogen atom at different rotations of a histidine which each are in an energy minima. This rotation may be the effect of a neighbour ligand (a further histidine). 


  • Abul KALAM Azad added an answer in Polymers & Microfluidics:
    Is it possible to convert pellets into granule form, granules into resin or powder form in polymeric materials?

    Is it possible to convert pellets into granule form, granules into resin or powder form in polymeric materials?

    if we convert the appearance of the polymeric material from one form into another form like pellets into granues, will it change any properties?

    Abul KALAM Azad

    Thank you samy,

    if u have any files, then send me to understand better.

  • Oleg B. Gadzhiev added an answer in Lanthanide Complexes:
    How to optimize a structure of a lanthanide complex by DFT (Gaussian09)?

    I am trying to optimize a Eu3+ complex by DFT using gaussian09. I am currently using Ub3lyp and Gen (with 6-31g for common atoms and MWB28 for Eu). The calculations has been running for a week and I still haven't completed the first cycle (only 70 iterations done...). Does anyone have a better optimization sequence?

  • Jasim Ahmed added an answer in Dehydration:
    I am trying to study and characterise calcium in milk. Some instruments need the samples to be in solid form. How do i dehydrate milk in low Temp?

    I tried dehydrating in oven at 100 Celcius (BP of H2O) but it darkens, with bad odours and get spoilt. 

    Jasim Ahmed

    Freeze dry the sample.

  • Yogesh Chaudhari asked a question in Cellulase:
    Which yeast expression system should I use for the expression of cellulase gene..?

    I have a cellulase gene of 376aa size. I want to express it into yeast expression system. Which expression system or technology should i use..??

  • Jasim Ahmed added an answer in Glass Transition:
    What is the Tg (Glass transition Temperature) of Triphenylamine?

    Organic Materials

    Jasim Ahmed

    Just run the sample in a DSC and find it. If you do not have one send me the sample I will help you.

  • David Mathuva asked a question in Kenya:
    What is a good measure of credit union (savings and credit cooperative - SACCO) efficiency?

    Any suggestions of good measures of credit union (SACCO) efficiency? If you would also like to collaborate on such a study, let me know. I intend to pursue a study on credit union efficiency in Kenya, a developing country with a vibrant credit union sector. Please share your thoughts...

  • Hidayat Marwat asked a question in Public Sector:
    Can anyone recommend literature on "Impact of globalization on public personnel recruitment"?

    I'm interested in exploring the relationship of globalization and public sector recruitment in the case of developing countries.

  • Jérôme Juilleret added an answer in Desert Ecology:
    Are wadi sediments in an arid desert considered a kind of soil?

    Sediments of these wadi are composed mainly of sand 

    Jérôme Juilleret

    Dear Yehia,

    every organic or mineral material at the earth surface is a soil in a broader sense.

    So wadi sediment is also a soil even if made of pure sand.

    In a restricted sense, soil  (better to say solum) is the material under influence of pedogenesis mainly characterized by new colour and structure development (compare to the rock structure of the sediment) under influence of biota and physical processes, translocation of clay, accumulation of organic compounds and salt  etc...

    In a arid system, your wadi sediment will not evolved in a thick solum but can show some signs of pedogeneses mainly  salt and carbonate precipitation.

    For mapping and scientific communication  purpose, soil scientist use 2 world wide system, the Soil Taxonomy (USA origin) and the World Reference Base (WRB).

    Both are classification system and you have to follow a key to see what soil do you have.

    By experience, as I am use with WRB if your wady soil is made of pure sand on more than 1 meter, your soil will be classified as Arenosol, if the texture is not only sand or if you have too much pebbles it will be classified as Fluvisol (because your sediment is of fluvial origin).

    Best regards

  • Adam L Vanwert added an answer in Molecular Biology:
    Any suggestions for establishing a Tetracycline inducible mammalian cell line using the TRex system from Invitrogen?
    For the last couple of months I have been trying to establish an inducible HaCaT cell line using the TRex system from Invitrogen. I am following the standard protocol (first transfect with pCDNA6/TR, select positive clones using Zeocin, then transfect with pCDNA4/TO, select positive clones using blasticidin and screen single clones). However I have not been able to get good expression of my protein upon addition of tetracycline. All the clones are either not inducible at all or leaky (protein is expressed even in the absence of tetracycline) and the difference between Tet- and Tet+ is not high enough. Am I missing something here? Is it possible to get good inducibility using this system?
    Adam L Vanwert

    It is supposed to be hygromycin for the TO plasmid,  basic udine for the TR plasmid,  and Zeocin only prior to the TO/pcDNA5/gene of interest/FRT plasmid.  Zeocin should not be used after the final transfection unless you want to kill the cells for verification as a control. 

  • Sumedh Ramachandra asked a question in Malaria Elimination:
    Operationally, how can genotyping assist malaria elimination efforts?

    We know that malaria genotyping is being increasingly performed across the board, albeit for research purposes. What questions does genotyping help answer and how can this be used by malaria programs?

  • Jaime Moreno-García added an answer in Penicillium chrysogenum:
    Anyone expert in Penicillium chrysogenum, how can I count total cells and measure viability?

    Anyone expert in Penicillium chrysogenum, how can I count total cells and measure viability? Thanks

    Jaime Moreno-García

    Thank you very much Cássio, the paper was helpful

  • Kevin C Chen asked a question in Recording:
    How to place stimulating & recording electrodes for in vivo hippocampal fEPSP recordings?

    I want to do fEPSP recordings on the Shaffer-CA1 pathway in vivo in the middle part of hippocampus in rat. I checked the literature and found conflicting results.

    For example, in the work of Doyle et al. (J Neurosci, 1996,  vol 16, 418-424) and their later works, the recording electrode was placed closer to the Bregma than the stimulating electrode was (recording electrode: AP -3.0, ML 2.0; stimulating electrode: AP -4, ML 3). 

    However, in some other works, e.g., Bliss et al. (J Physiol, 1983, 341, pp617-26), it is the stimulating electrode that is closer to the Bregma  (stimulating: AP -3.4, ML 3.2; recording: -4.4, ML 3.0). Both claimed that they were stimulating and recording the CA3-to-CA1 pathway. How could they had the exact opposite way of placing the stimulating and recording electrodes when both claimed to stimulate & recording the same pathway? These  are just some examples. I found more reports with  conflicting coordinates.

    I am wondering if anyone has a clearer answer on that, and can tell me the accurate way to place the electrodes on CA1 pathway in rat hippocampus.

  • Riaan F Rifkin added an answer in Arthropod Vectors:
    Where can I obtain DNA Primer Sets (CO1 and YCF1) for Canis lupus familiaris, Bos taurus, Zea mays and Sorghum bicolor?

    These are to be used as controls for archaeological sites predating their introduction to South Africa after 2000 years ago. I am also interested in Primer Sets for arthropod disease vectors (fleas, mites, ticks and lice) and indigenous southern African games animals (specifically antelope species).

    Riaan F Rifkin

    Thank you Revil and Jerome! 

  • Sunny Zafar asked a question in Boron Carbide:
    How to cut sintered silicon carbide (SiC) and boron carbide (B4C) plates?

    I have 4 x 4 inch, 8 mm thick silicon carbide (SiC) and boron carbide (B4C) sintered plates. How to cut these plates to prepare specimens?


  • Imtiyaz Bhat asked a question in Pyrimidines:
    Can any one help in How to do the controlled and selective protonation of amines?

    Actually I have synthesised a tetrahedral  coordination cage out of Pt based acceptor and pyrimidine appended triphenylamine based donor ligand .Now I want to selectively protonate the  central Nitrogen of the triphenyamine without causing any demage to the cage or Pt-Pyrimidine bond...

  • Sunwoo Kang added an answer in Theoretical Chemistry:
    How do I use QST2 in Gaussian to find Transition State?

    I'm trying to re-create the results from (Theoretical Chemistry Accounts 125(3): 269-278) where the authors determined the transition state and activation energies for DNA-nucleobase alkylation by sulfur mustard/ mustard gas.

    When I try and run these calculations, I get a termination error (/export/software/GaussianNew//g09/l101.exe). I was wondering if anyone could offer insight or try and recreate the results from this paper and maybe give a walk through of how this is done. Admittedly, I am not a computational chemist - I try and stick to synthesis but am working on an independent proposal for my PhD program and wanted to learn more about this field.

    Thanks in advance for your help!


    Eric Z

    Sunwoo Kang

    QST3 method show better performance and results than QST2 but there still has problem. You should insert initial geometry of transtion state but sometimes it appears siginifcant error during calculations due to bad initial geometry. I recommend that  you designed initial geometry of transition state then calculate with TS keyword. The end of this calculation, you may get much better TS geometry. Using of this geometry, you can perform QST3 calculation. It probably give less error during calculation.

    Hope this help

  • Khelassi Abdeldjalil added an answer in Learning:
    We use the CBR for learning new attacks, what are the attributes and values that we can have to construct a base case

    Thank you in advance

    Khelassi Abdeldjalil

    I think that the similarity exist in the attacker model (socio-psychological ...) also the behavior before the attacks.

  • Mahesh Samant added an answer in Earth:
    Has anyone worked on how extremophiles process information?

    Extremophiles -bacteria and archaea- are fundamental for the understanding of life on Earth - and most probably beyond the Earth. The knowledge about higher or superior living forms surpasses, by and large, the knowledge we have about extremophiles.

    To be sure, one salient feature of life is that living beings do process information. Whereas much research has been carried out regarding mammals and plants, very little or nothing has been said in respecto to the various extremophiles (acidophilus, etc.).

    I am trying to do some research on this issue. Could you please help me? Thank you very much.

    Mahesh Samant

    thanks arthur, even i would refer joanna papers on RG. since i had future plan of working on it....thanks carlos sir for your input too....

  • Jianrong Feng added an answer in Simvastatin:
    Is Simvastatin the best Statin to be combined with Colchicine?

    According to one of Garin Sahip's studies, Rheumatology International 28(3):289-91 · January 2008, the safest combination of Colchicine is with Simvastatin.

    My question is: does anybody have any life-experience to confirm this?

    Jianrong Feng

    Thanks for your reply, Stanton. I can't agree with you more. Regular monitoring and checkups is the best way to detect the interaction or side-effects if any and take timely measures, regardless which statin is being co-administered together with colchicine.

    I just wonder if the patient already on colchicine has to start taking statin, isn't it wise to start from Simvastatin first, instead of other statins, and closely monitor the co-administration outcome as it seems statistically there is more evidence Simvastatin interacts with colchicine less dangerously than other statins do.

    Your opinion?

  • Chandrakala .V asked a question in Nanorods:
    Is there any possiblity of quantum confinement in tio2 nanorods synthesized by hydrothermal method

    The band gap of the synthesized nanorods( 3.5 ev) are found to be greater than the bulk after dye sensitization. so is there any correlation between the increased band gap value and quantum confinement( decresing particle size)

  • Truong-Xuan Do added an answer in eHealth:
    Can you suggest an innovative Doctoral research topic in Computer Science, close to Internet of Things and e-Technologies?

    Research in Computer Science and ICT spans over a huge area. However, I would like get suggestions on the innovative topics related to e-Technologies. This obviously includes areas like Internet of Things, eHealth and eLearning. 
    However, any innovative doctoral research concept somehow twined to Computer Science is welcome.

    Truong-Xuan Do

    Researches for IoT on the IP-based network platform are quite popular, I suggest that you can research about IoT on Content-centric network which is a new paradigm for Internet architecture

  • Bernd Schmeikal 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.

  • Khaled Mohammed-Geba added an answer in DNA Barcoding:
    What are the best journals for DNA barcoding of Invasive crustacea?

    We could identify a crustacean invader to Egyptian waters by DNA barcoding (using COI gene). The invader is a parasite for fishes. What are the best journals I can  submit this kind of work on (other than Biological Invasions?)? It is the first time to appear in Egypt..

    Khaled Mohammed-Geba

    Thank you both Alexandra and Thierry. I agree in that an original work with direct aim and clear results should be published more easily and widely so as to be readily accessible to the interested investigators and authorities. This, I think, opens doors for more investigation and better understanding for the organism and the problems it causes, which are not easy at all. I respect your suggestions, they are really good . I tried Marine Biology Special Issue but they preferred more wide-range work..Then, I submitted it less than a week ago in ¨Journal of Fish Diseases¨ where I found some similar reports for this crustacean parasitic group. So, in case of other rejection, I would go to these three ones according to your kind suggestions: Cahiers de Biologie Marine, Crustaceana, & Turkish Journal of Zoology, in order..

    Thank you very much again. It was a real pleasure and honor for me to recieve your ideas and suggestions

    All the best