Q&A

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  • Rita De Vuyst added an answer in De-Broglie Bohm Theory:
    99+
    How do you see the non-locality of the wave-function and why it can't be used for the faster than light signaling?

    The wave-function describes a form of quantum energy called the quantum potential which propagates throughout space. Disturbing the quantum potential in one location instantly modifies it throughout the whole space. How you see this aspect related to the velocity of light?

    Rita De Vuyst

    It's a fact that the whole literature is difficult to analyse, each author is a universe on its own, perfect to see what consciousness is about. But at the side of causal thinking there is no logic in it and most of all it is put aside together with other illusions, as I heard  in a lecture in Afkikker last week by a philosopher. Witches, homeopathy, god and literature belong to the sphere of illusions. At the end they come to the conclusion that illusions may be useful.

    It is possible that we already have a split in mankind and that 2 groups we call human are already developed, and never can meet each other but be doomed to live in a cold war. The fact that there is war happening   in the world in the year 2016, must have its roots in the brain of those who take the power. Power is the negation of consciousness.

  • François Xavier Nshimiyimana asked a question in Soil Contamination:
    New
    How calculate health risk, from soil contamination (by heavy metals or pesticides) according to US EPA Method, ?

    Can you help me, please. I want to make the assessment risks in soil. with the documents support, if you have. thank you

  • Luis Miguel Constantino added an answer in Project Proposals:
    1
    Can anyone guide me where can i put the Project for Conservation of house sparrow?

    I want to start working on house sparrow i need guidance where can i put project proposal.

    Luis Miguel Constantino

    Hi Palak:

    You can contact The U.S. North American Bird Conservation Initiative (NABCI) Committee is a forum of government agencies, private organizations, and bird initiatives helping partners across the continent meet their common bird conservation objectives.  See more in the following link

    http://www.nabci-us.org/main2.html

  • Masoud Ovissi added an answer in Ternary Diagram:
    1
    Crustal amphiboles or Mantle amphiboles?

    Recently I read a review paper written in Chinese in 1980s talking about composition of Calcic Amphiboles and its petrology significance.The Si-Ti-Al ternary diagram, Al-Si diagram, TiO2-Al2O3 diagram et al. are used to distinguish the amphibole derivations(Mantle one or crustal one?).

    My question is these criteria is right(suitable) or not today.

    Thank you very much!

    Masoud Ovissi

    Dear Shu,

    The "Mantle Amphibole" statement is mentioned in these papers. As you see the publication date is more recent than chinese one. But I couldn't find any paper in which the "Crustal Amphibole" is mentioned.

    Popp, Robert K., Heather A. Hibbert, and William M. Lamb. "Oxy-amphibole equilibria in Ti-bearing calcic amphiboles: Experimental investigation and petrologic implications for mantle-derived amphiboles." American Mineralogist 91.1 (2006): 54-66.

    Frezzotti, Maria Luce, et al. "Chlorine-rich metasomatic H 2 O–CO 2 fluids in amphibole-bearing peridotites from Injibara (Lake Tana region, Ethiopian plateau): nature and evolution of volatiles in the mantle of a region of continental flood basalts." Geochimica et Cosmochimica Acta 74.10 (2010): 3023-3039.

    Powell, William, et al. "Mantle amphibole trace-element and isotopic signatures trace multiple metasomatic episodes in lithospheric mantle, western Victoria, Australia." Lithos 75.1 (2004): 141-171.

    Li, Jianping, and Sheng Zhang. "Redox state of amphibole-bearing mantle peridotite from Nüshan, Anhui Province in eastern China and its implications." Science in China Series D: Earth Sciences 45.4 (2002): 348-357.

    Kheirkhah, M., et al. "Mantle amphibole control on arc and within-plate chemical signatures: Quaternary lavas from Kurdistan Province, Iran." EGU General Assembly Conference Abstracts. Vol. 14. 2012.

    Popp, R., W. Lamb, and H. Hibbert. "Mantle H2O-Activity Estimated From Amphibole Equilibria." AGU Fall Meeting Abstracts. Vol. 1. 2004.

    Rosatelli, Gianluigi. The petrogenesis of carbonitic rocks and their relation to mantle amphibole and carbonate as exemplified in contrasting volcanoes from Vulture, Italy and Rangwa, East Africa. Diss. University College London (University of London), 2002.

    GENTILI, SILVIA. "MINERALOGICAL AND PETROLOGICAL STUDY OF MANTLE XENOLITHS FROM VICTORIA LAND (ANTARCTICA): INSIGHT OF THE ROLE OF THE AMPHIBOLE IN METASOMATIC PROCESSES."

    Also you can find the Hawthorne, Frank C., et al. "Nomenclature of the amphibole supergroup." American Mineralogist 97.11-12 (2012): 2031-2048. in attachment.

    Truly Yours,

    Masoud Ovissi

  • Vladimir Dvoryanchikov added an answer in Schoenlein-Henoch Purpura:
    5
    Do you consider Extra digestive Helicobacter pylori skin mafestations, EdHpSm as maker to gastric disease condition?

    Helicobacter pylori are gram-negative; microaerophilic spiral rod-shaped bacteria and they lead to gastritis, duodenal or gastric ulcer and even in rare cases to gastric carcinoma or Mucosa Associated Lymphoid Tissue (MALT) lymphoma. Based on a number of reports, a possible relationship of H. pylori infection to a variety of different dermatosis has been suggested, including urticaria, rosacea, acnerosacea, atopic dermatitis, alopecia areata, Sjögren’s syndrome, Schönlein-Henoch purpura, and Sweet’s syndrome.

    Vladimir Dvoryanchikov

    You too!

  • David Glyn Roberts added an answer in Empirical Research:
    7
    Is it even theoretically possible that we infer that a set of conditions are sufficient, using empirical methods?

    I am not in the Medical field myself, but I really admire it. However, as a person who uses stats in my job, it boggles my mind how we keep hearing that the folks doing medical studies have discovered "the gene responsible for X" or the "cause of Y". I really wonder how causation inference work in medical studies. Here is how I think about it:

    It is safe to say that we can observe sets of conditions that frequently occur along with a phenomenon (correlation), and let's now focus on preconditions only (greatly simplifying the problem). I think that for a set of conditions to cause the phenomenon, they must each be necessary for the phenomenon and, together, they must be sufficient. Now, let's see if we can infer necessity and sufficiency. Necessity means that there is not a single observation of the phenomenon where the condition was missing. So, arguably we can infer necessity, albeit being a tough job and the result must be labelled by the infamous "to the best of our knowledge". Sufficiency is the one I am struggling with. Is it even theoretically possible that we infer that a set of conditions are sufficient, using empirical methods?

    David Glyn Roberts

    I hesitated to respond because I don't want to put people off QCA or comparative case studies.  I am an advocate for Mill’s comparative case analysis and the method of difference. Comparative case studies and QCA look at phenomena post hoc and try to identify features common to different results, or at least present in several similar results. It is often the most appropriate way to collect evidence about complex situations where there are often multiple unknown variables and experimental methods are not suitable.

    Causal inferences

    That said, I disagree with the assertion that the method of difference does not attempt to draw causal inferences.  Why use them at all if you are not trying to draw causal inferences? 

    Mill wrote of the method of agreement,

    If two or more instances of the phenomenon under investigation have only one circumstance in common, the circumstance in which alone all the instances agree is the cause (or effect) of the given phenomenon” (Mill 1967, p. 390).

    He also wrote of the method of difference

    "If an instance in which the phenomenon under investigation occurs, and an instance in which it does not occur, have every circumstance in common save one, that one occurring only in the former; the circumstance in which alone the two instances differ, is the effect, or the cause, or an indispensable part of the cause, of the phenomenon. (Mill 1967, p. 391)

    Quite what Mill meant by ‘cause’ is debatable. As a philosopher Mill must have read Aristotle on cause. Aristotle recognised four different causes: 

    ·       The material cause: “that out of which”, e.g., the bronze of a statue.

    ·       “The formal cause: “the form”, “the account of what-it-is-to-be”, e.g., the shape of a statue.

    ·       “The efficient cause: “the primary source of the change or rest”, e.g., the artisan, the art of bronze-casting the statue, the man who gives advice, the father of the child.

    ·       “The final cause: “the end, that for the sake of which a thing is done”, e.g., health is the end of walking, losing weight, purging, drugs, and surgical tools.” (Stanford Encyclopedia of Philosophy)

    Mill may have meant some or all of such ‘causes’ but the use of the word ‘effect’ suggests that he probably thought of cause pretty much as ‘efficient cause’ and probably very similar to current research ideas about cause, which is defined in the Oxford Dictionary as

    that which produces an effect , or gives rise to an action, phenomenon or condition.’ (Oxford Dictionary)

    I understood Dr Theim to follow Mill and assumed he meant that necessary and sufficient conditions are associated with causality. I may have misunderstood him but I am surprised that he now argues that they are not associated. It is difficult to see why one would bother if one did not intend to imply a causal relationship.  Indeed Dr Theim says as much when he wrote:

    Two methods that can draw causal inferences on the basis of necessary and sufficient conditions are …”

    and

    QCA implements a theory of causality that assumes causal structures to be representable in Boolean expressions.”

    Difference between co-occurrence and conditions

    I accept the argument that Boolean logic, in and of itself, describes co-occurrence and says nothing about any possible relationship between phenomena, nor does it imply temporality between the events. 

    However, when one starts talking about necessary and sufficient conditions, or ‘causes’ in Mill’s case, then one is describing a relationship.  Indeed it is a well-established principle in formal logic that a necessary or a sufficient condition describes a relationship between the two phenomena. It implies more than co-occurrence of the two phenomena. 

    The characteristics of Boolean logic do not define the method of difference or the method of agreement (or their use in QCA).  Boolean logic is a tool used by QCA and the characteristics of QCA derive from the method of difference and the method of agreement, not from Boolean logic.

    I won’t write more on ‘conditions’ here, except that Dr Theim was correct when he pointed out that I omitted to mention that there are conditions that are both necessary and sufficient. N can only occur if S has also occurred (S is both a necessary and sufficient condition for N). 

    My comment that “If you have a sufficient condition, there are no necessary conditions.” was poorly worded.  I meant of course that if one has a sufficient condition, then the change will occur without any separate necessary conditions.

    Other causes

    The problem I have is that observation post hoc does not allow one to identify whether a condition is ‘necessary’, or ‘sufficient’, or ‘necessary and sufficient’. 

    What if,

    N can occur even when S does not occur

    But we have not observed such an instance

    Post hoc observation of complex, uncontrolled events cannot exclude the last possibility.  Co-occurrence may be totally unrelated or be the result of some unobserved, underlying causal factor.

    Both Mill and Ragin recognise the alternative cause argument. Mill made an extended and cogent argument that “the method of difference is inapplicable in social science.” Schlosser et al reiterated the argument that such methods

    “ … may not prove (stress in original) any causal relationship, because it is most often impossible (in social science at least) to test a clear and complete (preconceived) model of such links and to sufficiently “control” for other factors. They constitute, however, a valuable step toward eliminating irrelevant factors and approximating causal conditions in the “real” world." (Schlosser, Meur, Rihoux and Ragin 2008)

    In other words the value of QCA is to test and falsify hypotheses.  It does not prove the relationship but it can invalidate the hypothesis. It can be used to identify evidence to test a theory.  It should not be used inductively to develop theory (see Sekhon 2004, Perspectives on Politics, 2 (2): 281).

    I suspect that the difficulties of applying the methods of difference and agreement led some proponents of QCA to argue that necessary and sufficient conditions are not causal.   Such arguments reveal an inherent contradiction.

    Such arguments that QCA or the method of differences I acausal go against the fundamental premises of the method of difference and the method of agreement, which are causality.  To go back to the first two quotes in this post, Mill asserted that where an observed circumstance (or condition) is the only difference between phenomena (or is the only common factor) then it is the cause of the difference (or the common cause of the phenomena).  Ragin does not quite say this (though he does quote Mill on this point). However, the logic of the method of difference and the method of agreement (even in QCA) appears to lead inexorably to causal inferences. Lieberson (1991, Social Forces, 70 (2): 307)) argued that such methods should not be used without “more rigorous justification of heroic assumptions and a guard against possible distortions.” (p.307) 

  • İhsan Basaran added an answer in PLA:
    1
    What is a reliable source on compressive properties of PLA?

    Hello all,

    there is very few work published on compression testing of polymers such as PLA and a lot on tensile testing. I am looking for a reliable source on the strength and modulus of PLA under compression testing. Can anyone recommend one?

    Thanks in advance.

    İhsan Basaran

    That is an interesting deficiency in the literature. That is extremely attractive. I guess the absence of compressive test for PLA can be related to PLA's end-use's. Researchers could think that it is unnecessary. I am following this question, thank you for coming up with this curiosity Christiane.

  • Govind Pandey added an answer in Fish Diseases:
    3
    Is Penicillin useful in the cure of fish diseases?

    Penicillin is an antibiotic and useful in many diseases.

    Govind Pandey

    Thank you very much for this important citation.

  • Aiman Shamim added an answer in Magnetic Materials and Magnetism:
    10
    What is superparamagnetics?

    Magnetic nanoparticles exhibit superparamagnetism how it is different from paramagnetism?

    Aiman Shamim

    How could define, localized surface plasmon resonance of metal nanoparticles ? how it is different from molecules having conjugation in them?

  • Kenneth M Towe added an answer in Clay Minerals:
    1
    How to know the distance between oxygen/Hydroxyl on clay mineral surface?

    Hello everyone! I am currently studying about clay minerals and I dont have enough background about it since I am new to this topic.

    I have learned that clay mineral surfaces has a negative charge and mostly containing hydrohyl groups or oxygen which can be attached to cations in soil in order to adsorb it on clay mineral surface. 

    Now I am interested on how to measure the distance between one O/OH to another O/OH on the surface of clay. ex. O-O distance and also in the case of ferric hydr/oxides, Id like to know the distance between O-Fe-O

    I hope somebody could help me in this since this will help build my foundation in studying adsorption by clay minerals. I am looking forward to your valuable opinions and knowledge about this matter. 

    Have a nice day all!

    -Sarah

  • Govind Pandey asked a question in Carcinogens:
    New
    Which heavy metal is the most dangerous carcinogen of fish and why?

    Certain heavy metals are known to be carcinogen in fish.

  • Mohan Chandra Pradhan added an answer in Aluminium:
    1
    What is the feature of clean aluminium melt in a Prefil-Footprinter test?

    What is the curve feature of clean aluminium melt in a Prefil-Footprinter test?

    Mohan Chandra Pradhan

    Dear Dr Mostafaei

    please check the attachments if it is helpful for you.

    thank you

    + 1 more attachment

  • Mohan Chandra Pradhan added an answer in MATLAB:
    1
    Raster plot representation for neural spikes ?

    I am analysing some neural spike data. It is in an array, with each value being the time at which a spike event occurred, I want to be able to display an x-axis of times,and draw a raster plot when a spike occurred Does anyone know how I might achieve this using  MATLAB? Thanks in advance

    Mohan Chandra Pradhan

    Dear Dr Ghandour

    please check the attachments if it is helpful for you.

    thank you

    + 1 more attachment

  • Marko Popovic added an answer in General Relativity:
    99+
    Universe is static!!! Yes or no?

    Space of Universe is static! Yes or no?

    Question: Are there any observations that do not fit into the model static space of Universe, are there any theoretical obstacles to the existence of such a model?

    I assume that the Universe is eternal, infinite and static, it is not expanded and not curved, it is possible to construct a preferred inertial frame of reference in which the CMBR is most isotropic. The matter in this space evolves, but the average density of matter and energy (in large enough volumes) fluctuate within a rather broad range.
    The light in this model is "tired", the speed of light depends on the optical density intergalactic medium. Gravity is also "tired" t.i. weakens a little faster R2. The energy of destroying matter goes into the surrounding vacuum. The excess energy from the vacuum give rise to new particles of matter.

    I state that all the observed cosmological effects can be explained in such a Static Model of the Universe.
    See attached "Basic_Cosmological_Formula_1_En.pdf"

    Dear colleagues, I do not ask, what are the problems faced by other theories (though I would be interested in your opinion on that. The General theory of relativity is not applicable to the entire space of the Universe).

    Marko Popovic

    Dear professor Brändas

    Relativistic mass! if universe accelerates then....? It actually accelerate isn't it!

  • Roya M. Dayam asked a question in Neutrophils:
    New
    Does anyone have the experience of RAC1 pulldown in neutrophils?

    after isolating the neutrophils, I need to pretreat my cells for 30 min with a drug and then add fmlp (2uM, 1min). during that 30 min incubation I leave my cells in Ca free PBS at 37 0C. 

    I have tried different media like DMEM, HBSS, and Ca free PBS, but still my resting cells have the same level of RAC1-GTP as fmlp treated cells. any suggestions? 

  • Stephen Crothers added an answer in Foundations of Physics:
    99+
    Do you agree with Stephen Hawking's recent conclusion that black holes don't exist?
    Black holes don't exist. I published this many years ago. Cantor's Universe doesn't allow the concept.

    Stephen Hawking now came up with the same conclusion. Read: http://www.spektrum.de/news/es-gibt-keine-schwarzen-loecher/1222059

    In my opinion he is right this time. What is your opinion? Was he right then or is he correct now?
    Stephen Crothers

    Despite what the "present scientific knowledge" alleges, the black hole does not exist, and never existed. The black hole is a product entire of impossible physical attributes and violations of the rules of pure mathematics, and so the theory of black holes is false. Hawking has not disavowed the theory of black holes.

    http://www.principia-scientific.org/hawking-s-latest-incantations-on-black-holes.html

  • Sajid Khan added an answer in Raman Scattering:
    17
    Can anyone help with Raman spectroscopy of graphene and graphene oxide?
    What ranges of D and G peaks will suggest that Graphene and Graphene Oxide is synthesised as in the literature there are alot of variations like
    D peak ranges from 1320 to 1365
    G Peak ranges from 1560to 1595
    So help me in the correct peaks of G and D should lies in between given above?
    Sajid Khan

    dear Anis,

     there are various defects due to which the D peak arises. it does not occur due to single particular defect. so you may go on further characterization using TEM, XPS etc to get to know well. 

  • Govind Pandey added an answer in GSH:
    4
    How to determine the pKa of Glutathione (GSH) bound to proteins?

    https://www.ncbi.nlm.nih.gov/pubmed/2742854

    I am following the method of Graminski in the paper above. Whether GSH is protonated or not may be followed with absorbance spectroscopy at 239 nm. To determine the pKa of GSH, I follow the protonation or deprotanation of GSH over the pH range of 5-11.  I then repeated the experiment in the presence of certain proteins to see what effect they have.

    Calculating the pKa of GSH free in solution was no problem. The problem comes when I have to repeat the experiment in the presence of proteins. I am supposed to correct the Spectra for the absorbance that would otherwise be caused by just the protein or free GSH in solution. This however is impossible as in my case, the absorbance of free GSH is higher than my readings for protein+GSH together. 

    Have I misunderstood something?

    Govind Pandey

    Thanks.

  • Julie Bendix added an answer in Cluster:
    4
    Interpretation of negative loadings in discriminant analysis?

    Hi all

    We are using different independent variables to understand the intention to use and usage of mobile payment solutions. Dependent variable is intention to use.

    We have three discriminant functions loading according to the following:

    1) Result demonstrability (0,62), Compatibility (0,55), Perceived usefulness (0,54), Perceived ease of use (0,48), Risk (-0,44), intention to use (0,34)

    2) Trust (-0,60), Image (0,54), Enjoyment (0,43)

    3) Subjective norm (0,83)

    Our four clusters have the following group centroids:

    Cluster 1: F1= -0,97, F2= -0,28, F3= 0,38

    Cluster 2: F1= -3,6, F2= 0,76, F3= -0,23

    Cluster 3: F1= 1,98, F2= 0, 15, F3= -0,21

    Cluster 4: F1= -1,70, F2= -1,10, F3= -0,26

    We are a bit unsure of how to interpret the above. Especially with regard to the risk and trust constructs which both have negative loadings on functions.

    Can anyone help up interpret this?

    Your input is highly appreciated.

    All the best,

    Julie

    Julie Bendix

    Great, thanks Alexander!

    It's a little confusing with the risk-trust relationships and the negative loadings, but I think we are beginning to understand them correctly. We have already profiled the clusters by these variables, which confim the findings of the first function. However, the picture is a little more blurred on the second function, which is a little confusing.

    As a last question, we are also a little confused about the "which discriminant function is best at discriminating between the variables*. Is this important in the interpretation, or do you interpret by the group centroids (the mean values on the discriminant functions)?

    Thank you so much - and have a nice Sunday!

    Best,

    Julie

  • Vinod Kumar Rajput added an answer in Hummer's Method:
    2
    Whta does peak at 26 degree for Grahene oxide mean synthesized by modified hummers method?

    GO preparation

    Vinod Kumar Rajput

    peak at 26 degrees shows it is pure graphite, the peak for graphene oxide will raise on in between 10 to 12 degrees.

  • Harshvardhan Singh added an answer in Positive Psychology:
    3
    Do you suggest any books for psychology, abnormalities, and positive psychology?

    Do you suggest any books for psychotherapy, abnormalities, and positive psychology?

    Harshvardhan Singh

    Dear  Mustafa,

    Please see the attached link for 'Positive psychology' books. I hope you will find it useful.

    Regards

  • Stefano Quattrini added an answer in Gravitational Field:
    99+
    Is the clock rate of free falling clocks the same?

    In a gravitational field of a homogeneous spherical mass M, a sufficiently small mass B, compared to M,  is left free in the gravitational field of M at a certain distance H from the center of mass, outside his surface. B gains speed, relative to the center of mass M, because of gravitational attraction. Many small objects like B free fall from different heights or from the same height at different instants.

    Every object has an atomic clock on board. Would these clocks have the same clock-rates during the free fall?

    A reference, master clock has to be adopted, otherwise the problem is ill posed. Clock-rates are refererred to an atomic clock on the surface of M for example (negligible M  rotation speed).

    The time elapsed for each body to go from the same starting and ending point counted by the atomic clocks on board is certainly the same (UFF).

    Their clock rate should be different, in general, unless they start from the same position and instant. Not because  light takes less time to reach the closest, since they are in different positions, but  because there exists a  relation between the very small object and the massive object.

    I would like your opinion regarding this problem.

    Stefano Quattrini

    Eric,

    "In principle, you are right. Essentially what you are saying is that the weight of the components that constitute the mechanism of a clock could distort them so as to significantly change the rate of the clock. That’s imaginable, if the clock were extremely large and the gravitational field extremely intense. Do you really believe that your watch, for example could be measurably affected in that way?"

    Come on, I thought you considered me smarter than that. To Consider such infinitesimal effect is unthinkable , no way to measure them now, maybe in 2500 AD.

    "Consider a cesium atom in the Earth’s gravitational field, which can be described in terms of a gravitational potential. Consider the potential difference between the top and the bottom of an atom! Quite obviously that is utterly negligible (do the calculation!)"

    this is obvious and nobody would argue about the negligible effects of weak gravitation compared to the electromagnetic interaction.

    "How can one think that the atom is distorted sufficiently to change its transition frequencies - and to change them in such a way as to account precisely for the “gravitational red shift” when two such atoms are at different heights? That just doesn't make sense."

    I know that for you the view point of OKUN is unacceptable, because in principle it gives an alternative view. His argument is the only one which can explain why in a static situation there can be a difference in the final counting of two twin oscillators according to the rate (1+gh/c2), there is no other.

    "The point is that none of this kind of thinking is necessary: “proper time” as defined in GR accounts for “time dilation” (in particular the gravitational red shift) very simply and clearly in terms of ideal identical clocks ticking at the same rate, without any such bizarre imaginings!"

    yes and this would coherently imply that in a gravitational potential any clock would be in sync. The only way to make two twin clocks to be out of sync after having been in sync at first, is to change something. What is changed is the relative energy per unit mass in the kinetic time dilation, the one which has more kinetic energy per unit mass delays. 

  • Vinod Kumar Rajput asked a question in Hummer's Method:
    New
    How Does the silicon content effects the Graphene oxide properties?

    I am undergraduate student. I've produced Graphene Oxide using Modified hummer's method. In SEM/EDS results it shows some quantity of silicon in final product... ?where does it come from!  

  • Tahir Shafeeq asked a question in Enzyme Activity Assay:
    New
    Can we say that expression level of phenoloxidase (PO) is equal/ directly proportional to Prophenoloxidase (PPO)?

    Kindly guide that can we say that expression level of phenoloxidase (PO) is equal/ directly proportional to Prophenoloxidase (PPO)? as PPO is inactive form of PO.

  • Mohan Chandra Pradhan added an answer in Physical Compiler:
    1
    What is the advantages of using Synopsys Physical Compiler over Design compiler in Logic Synthesis?

    Can any one tell is the Synopsys physical compiler tool is available to the University customers? What are the advantages of using Physical Compiler over Design compiler in logic synthesis phase?

    Mohan Chandra Pradhan

    Dear Dr Sivanantham,

    the advantages may be as follows

    -Advanced optimizations deliver 10% faster timing QoR
    -Physical guidance to IC Compiler tightens correlation of timing, area and power to within 5% and speeds placement by 1.5X
    -Accurate pre- and post-synthesis congestion prediction and congestion-driven optimization eases routing
    -Gate-to-gate optimization for smaller area on new or legacy designs while maintaining timing Quality of Results (QoR)
    -Cross-probing between RTL, and design views such as schematic, timing reports and physical views for faster debugging
    -Early physical visualization and debugging identifies layout issues prior to physical implementation
    -Floorplan exploration for faster design convergence to an optimal floorplan
    -2X faster runtime on quad-core compute servers
    -Concurrent multi-corner, multi-mode (MCMM) synthesis.

    i am attaching a book also.it might help you.

    thank you

    + 1 more attachment

  • Mohabattul Zaman Bukhari asked a question in Graphene Nanoribbon:
    New
    Future of electronics will soon depend on graphene nanoribbons. Anyone know how to control the ribbons growth and their alignment?

    Graphene nano-ribbons can be grown directly on the surface of a semiconductor, but it's hard to control the ribbons growth, and at the same time, aligning them all in the same direction.

  • Malur Srinivasan added an answer in Cast Iron:
    2
    Basic micro structure analysis and explains for ductile cast iron?

    i need explain for the micro structure of ductile cast iron ( after casting ,annealing,quenching and tempering )

    thanks 

    Malur Srinivasan

    Attached are microstructures of as-cast, normalized and quenched and tempered. As-cast shows nodules in ferrite/pearlite matrix, normalized shows nodules in ferrite/pearlite matrix with pearlite being finer than in the as-cast specimen, quenched and tempered shows nodules in tempered martensitic matrix.

    + 2 more attachments

  • Lotfollah Emadali asked a question in GeoStudio:
    New
    Dear all; I have a question about Geostudio software module SIGMA/w?

    my email: bemead1390@ut.ac.ir

                     b_emad_1379@yahoo.com

  • Radha Krishnan asked a question in Gold Nanoparticles:
    New
    Gold nanoparticles is used in bio-sensor for removal of heavymetals,Why?Explain ?

    Gold nanoparticles is used in bio-sensor for removal of heavymetals,Why?Explain ?

  • Sravan Kumar asked a question in PLS:
    New
    How to define a crack front in this case and contour integrals. ??

    Pls give ur suggestions on this

    Is there any chance that u give field and history output requests for strain energy and u dont find it in results after running a job?????

    + 2 more attachments