Unruled Notebook

Entries from October 2007

Identify from its title, the music review of SVK

October 26, 2007 · 2 Comments

…and earn my respects for your uncanny nose for smelling out muddle from its altered spellings.All you need to do is take a look at the screen-shot of this week’s Friday review column from the Hindu and answer the question at the top of the picture below (answer at the end for the uninitiated)

svk_title_muddle.png

And before you reach for the answer, in our regular re-review of SVK review section, sample these pearls from the pen of Shri. SVK.He describes the talented veteran and respected Carnatic music vocalist Suguna Purushothaman thus

Her roots in the past helped her to introduce a rare break of old-worldliness turning her back on the denser commercial climate today. Her technique was directed to present different levels of depth and appeal. She sought to draw inspiration from consecrated principles, not to yield to spasmodic vague sentiments.

Notice the brilliant “roots in the past” usage. Weren’t we always into thinking that roots are usually spread into the present or the future?

And it gave him the revelation that “helped her to introduce a rare break of old-worldliness”. Only the “her” he describes is already crossing sixty. How else, if not introducing “old worldiness”, do one expect her to sing? What an obvious observation from a reviewer who, with his music knowledge, could have written more productively about the actual music nuances of the concert.

The next sentence gets even better. Her technique – god bless her, she had one that SVK could recognize – it seems, presented “different levels of depth and appeal”. Now, “different levels of depth” means from very shallow as in a level surface to very deep as in an abyss. And “different levels of appeal” means from very appealing to very unappealing. All this is possible because of her “directing her technique” as written in the first part of the sentence.

I rest my case. I don’t even want to ponder about the last sentence in that paragraph.

Anyway, the accompanist in that concert is not spared of the special SVK treatment, while the reader is left in the lurch whether he (SVK) is taking a pot shot at the artist or not with this one

M.A.Krishnaswamy on the violin was the alter ego of the vocalist and though on the same wave length he tightly framed the phrases with great lucidity.

Firstly, let us give the benefit of doubt to SVK, given his eminence in Dickensian English polemics, that his usage of alter ego means more “a trusted friend” rather the other meaning of it “the opposite side of a personality”.

So, the “violin was the alter ego of the vocalist” makes one think that the violinist followed and supported the vocalist very well – which is the job of him in a concert. All is well, we think, until we read the subsequent part of the sentence where the violinist “though on the same wave length he tightly framed the phrases with great lucidity.”

The violinist “though on the same wavelength“ even when taken literally means that he is in sync and pitch with the vocalist, although that is not what SVK means obviously. But even if this is so, the violinist manages to get out his “tightly framed phrases with great lucidity”, suggesting (to us by SVK) that the vocalist didn’t. So, now the reader wonders as usual: is SVK praises or curses, that too, is it directed at the violinist or at the vocalist?

My humble obeisance to the extremely talented lady artist of the day Mrs. Suguna Purushothaman (sample this: while singing a song, she can put correctly two different talams – meters – for that song, in either of her hands simultaneously!) for having to be picked as the protagonist of Shri. SVK’s review.

My condolences to our great treasure of Carnatic music for being relegated in this kaliyuga to get (non)explained by such pompous verbiage.

And the answer to the question at the start is of course,

“Bhairavi on a broad canvas” with a gist that reads “Good voice control lent distinctive charm to the picture.”.

Notice how both of these sentences describe music as a painting – substituting one art form to give the illusion of explaining the other, while actually doing nothing! That is the special talent of Shri. SVK.

[Although G. Swaminathan with his title Raga delineation carefully etched makes a valiant attempt to reach out to SVK, he fails miserably by his pathetically clear gist that reads "Sankarabharanam and Saveri were given equal importance at the memorial concert by Seetha Narayanan."]

Related Essays

Categories: Carnatic Music · Muse
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Notes on the Volume averaged Energy Equation for Porous Medium Flows

October 26, 2007 · 4 Comments

Porous medium by definition is made of at least two materials, one solid and stationary with respect to a reference frame and the other a fluid that could move (flow). Fluid flow in such a configuration has been discussed earlier and is governed by the momentum conservation statement also known as the Darcy Law or one of its extensions.

How to formulate an energy conservation statement that governs the temperature distribution under such porous medium convection situation?

The concept of volume averaging [briefly discussed here] is invoked in writing this energy equation. This equation is nothing but the first law of thermodynamics, applied on an open system where mass and energy are allowed to “cross” the boundaries that separate the system from its surroundings. [see also [[this note|First Law and Fourier Law]] on how the energy equation for a heat conduction situation is simply the application of First Law for a closed system]

In the following figure, the sample parallel plate bounded porous medium convection configuration is modeled as a homogeneous one dimensional heat and flow configuration as pictured. The Darcy Law in its global and differential form (text inside the green box in the figure) is taken to govern the momentum conservation in this particular case. The surface porosity is invariant in the x direction and hence equal to the volumetric Porosity?.

pm_energy_eq_2.png

[click on image for bigger picture] Figure 1: Schematic of the porous medium convection configuration considered for formulating the energy conservation equation

As one can expect, two energy conservation equations, one for the solid part and one for the fluid part could be written for this convection configuration as follows.

Solid side

(\rho c_{P})_{s} \left(\frac{\partial T}{\partial t} \right) = k_{s} \frac{\partial ^2 T}{\partial x^2} + q^{,,,} \cdots (1)

Fluid Side

(\rho c_{P})_{f} \left(\frac{\partial T}{\partial t} + u \frac{\partial T}{\partial x} \right) = k_{f} \frac{\partial ^2 T}{\partial x^2} + \frac{\mu}{K} v^2 \cdots (2)

Observe that the volumetric internal heat generation is present only in the solid side (the last term in Eq. (1)) and the viscous dissipation term is present only in the fluid side (the last term in Eq. (2)). Also, the viscous dissipation is modeled as the power required for the fluid to “extrude” (as used in reference [1]) itself over the porous solid structure. This is equivalent to the pressure drop in the Darcy form of the momentum conservation times the seepage speed, resulting in an expression of the form given as the last term in Eq. (2).

The concept of a Representative Elemental Volume (REV) [briefly discussed here] is the basic step for performing a volume averaging in a porous medium. If one were to solve these equations separately, an interfacial closure term involving a local convection heat transfer coefficient is required that account for the local heat transfer between the solid and the fluid flow. Obviously, this term is neglected in the above two equations. This is possible with an important but pertinent assumption that the temperature of the solid and the fluid inside an REV is identical. In other words, local thermal equilibrium between the solid and the fluid is assumed while writing the above two equations. Hence the temperature T that is present in both the equations (1) and (2) is neither the temperature of the solid nor that of the fluid but is that of the porous medium.

From the figure above it is obvious that the one-dimensional porous medium convection configuration is a “parallel” arrangement at the REV level. Invoking the volume averaging concept and combining the above two equations to obtain a single energy equation for the porous medium results in

(\rho c_{P})_{f} \left( \sigma \frac{\partial T}{\partial t} + u \frac{\partial T}{\partial x} \right) = k_{e} \frac{\partial ^2 T}{\partial x^2} + q^{,,,} + \frac{\mu}{K} v^2 \cdots (3)

Generalizing the above one-dimension equation for three-dimensions using vector notations, it would look like

(\rho c_{P})_{f}\left( \sigma \frac{\partial T}{\partial t} + V \cdot \nabla T\right) = k_{e} \nabla ^2 T + q^{,,,} + \frac{\mu}{K} V^2 \cdots (4)

Many simplifications are consciously swept under the rug in arriving at the above equation but let me explain the important ones alone and await discussion on any specific points that arise. First, a note on the effective properties viz. ke, and sigma . Owing to the parallel arrangement of the solid and the fluid flow in the REV level, the effective conductivity can be defined as

k_{e} = \phi k_{f} + (1 - \phi) k_{s} \cdots (5)

Other combinations of k_s, k_f, phi are possible depending on the modeling of the REV but that warrants a separate essay. Proceeding to the sigma, we note that it is the porosity weighted ratio of the (density times heat capacity) of the solid and the fluid.

It can be expressed for the parallel model of homogenization of the porous medium considered in Figure 1 as

\sigma = \frac {\phi (\rho c_P)_f + (1 - \phi)(\rho c_P)_s}{(\rho c_P)_f} \cdots (5b)

In the absence of heat generation within the porous medium and for negligible viscous dissipation effects, the above equation simplifies to

(\rho c_{P})_{f}\left( \sigma \frac{\partial T}{\partial t} + V \cdot \nabla T\right) = k_{e} \nabla ^2 T \cdots (6)

Which further simplifies for steady state to

V \cdot \nabla T = \alpha_{e} \nabla ^2 T \cdots (7)

where alpha_e is the effective thermal diffusivity of the porous medium ( = k_e/\rho c_P of fluid).

Some of the major assumptions in writing all of the above volume averaged energy conservation statements are as follows

  1. homogeneous porous medium
  2. local thermal equilibrium between the solid and the fluid of the porous medium exists in the REV level itself.
  3. effective properties used in the volume averaged energy equation are accurate in predicting the effects in the REV level.
  4. the rest of the primitive variables, u, P and T are volume averaged quantities defined on a porous continuum.

Reference

Categories: Lecture Notes · Porous Medium · Research Notes · Thermal Sciences
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What kind of writing pays best?

October 25, 2007 · 1 Comment

Ransom notes

—– Elmore Leonard

[and his ten rules for writing]

Categories: Books

How Useful is the Web

October 25, 2007 · Comments Off

Is the web (internet) useful for me and my scientific work at all? In what way and how it could be improved? Now that I am used to having a stable high speed internet connection inside my home-office ivory tower, instead of cribbing about the perennial ills of my third world corner, let me ponder on the answers in an unavoidably self-centered take.

I reiterate that I am interested only about the scientific uses of the web pertaining to my work as an academic. Also, the ubiquitous Google search, perhaps the first thing anyone with internet access uses nowadays, is excluded from the discussion. Google search is easy to use but the information it brings is not always reliable.

So, What actually is easily accessible for me?

My website. Rudimentary information about a professor and/or researcher from their generic academic website is easily accessible for me. Most of them are however not updated for various reasons, rendering them to be of little more use than their office door signs. Some researchers do maintain latest information about their research work, which I find useful.

Another thing that is of easy access are the published research literature in journals and science magazines. That is, when my institution has paid for the subscription access or when the journal releases information in the public domain. This caveat makes it not totally easy – see discussion below. Also, searching and buying a technical book using my credit card in online shops like Amazon is easy. But shipping the book to my third world corner can still be a major hassle.

What else? I do experiments for my research. Some of the product and equipment information and some thermo-physical property data of common materials are easily accessible on the web.

On the other hand, there is easy, free, “knowledge” available – such as in the Wikipedia, but more than a sizable percentage of them is unverified. I would double check with my peer-reviewed library resources before using such unverified knowledge.

There are also things that are required by me but are difficult to access in the web

All things listed under the earlier “easy access” can at times become very difficult to obtain. Online archiving of all journal literature is not yet complete. What is available in the engineering sciences is only knowledge from the past two decades.

Scientific information – at least most of it – still reside in formal peer-reviewed publications. Even as I write this note, I am frustrated in not finding some crucial piece of information for modifying constructively some of my research papers that require minor but pertinent revisions before acceptance. The information I seek lies with papers that are published between 1920 and 1980, most of which – or the relevant information they carry – I am unable to obtain online. Not because they are behind a subscription wall but because they are not available there yet. The frustration is amplified because my library also doesn’t have them as hard copies.

This state is afflicted by lack of funding in third world countries, rendering even their top tier academic institute libraries not to have access to all the quality journals in a particular domain of science. For instance, our institute has subscription for Nature but does not have for Science. Although my situation is better than, say, a decade back, I hope soon all such available knowledge in journals in all fields come out on the web for free access.

Some of the web-obtained product or property information are obsolete. It requires reliable and established knowledge from technical books, access to which are still difficult to obtain online.

Both the non-availability of books and journals is also chiefly due to the violation of publisher copyright issues rather of the authors’. Given my academic job position, as an author, I would encourage my research and technical knowledge to reach as many people as possible. A web-based business model that is profitable for the publisher and the author, also allowing easy access for researchers and informed citizens to pertinent knowledge is the need of the hour.

Open access [1], as in free availability of human knowledge online, is a distant reality [2].

Now for some of the web-based tools I use to share my research stuff with other scientists.

I maintain a professional website with brief information about most of research topics and this website with other notes and essays I write. This in principle can include even images and presentations talking about my research. I also write here about my research and related science extensively.

On the other hand, I don’t keep my published papers (as pdf etc.) online. I like to receive emails asking for my papers. It gives me a chance to know who is interested in my research and why.

Do I use the web in my collaboration with other researchers and colleagues ?

Yes. Let me discount email for the moment, to cite other web based applications that I use to collaborate. There are online storage repositories accessible through ftp, for sharing the entire project file folders. Such storage exists for me both in my institutional servers as well in paid outside ones.

I was using Google Docs and Zoho to share and discuss documents. Sometimes I also share experimental data in spreadsheets this way. I don’t use them now.

One major restriction with such online facilities are the lack of a smooth integration of mathematical fonts and symbols for typing equations that are part of any of my research document. I am yet to find an online solution that is satisfactory.

When the idea we work on as a team matures, different parts of the required research to polish the idea gets assigned to each of us collaborators and use of such online tools reduce. The final drafts are exchanged over emails.

I also attempted to use the intra-institutional document repositories and software for scheduling meetings with notifications through email. I also managed a PmWiki installation, accessible within my research group. A rudimentary e-print archive hosted in my research server can also be included in such web services that are useful for my scientific work. But all such web based facilities fell into disuse after a while. They don’t actually help save one’s time.

Are there any current favorite science-related websites and web applications for me?

Most of my online science related reading is through research journal or science magazine articles. This makes websites with search facilities for such content [3], my often used websites. Other specific sites include arXiv.org e-Print archive and a few magazine websites [3].

All such links can be accessed through this site [3], making it one of my favorite websites.

I follow some science related blogs and news feeds nowadays, using Google Reader and Bloglines (their beta version is great), making them my current favorite web applications.

A few areas where I would like to see improvement at the earliest so that it is useful for my scientific activities.

I would like to share my research and academic manuscripts fully online. For this I require a software or group of software seamlessly integrated that handles all my writing needs on an offline computer and should tranfer the written notes into many forms (pdf, html, other media formats). The software should also handle math, data and image manipulation. Google Docs or Zoho is a start but requires lot of suitable plugin integration and feature implementation before this could be achieved. Scribus is a promising venture in this front, which I am yet to explore to comment on.

I would like to have most of the already available and reliable online knowledge to be accessible from one place. Google Custom Search or Lijit that does the dirty work of searching all the sites I require it to, are promising starts in this direction. I have a custom Google search [Entropy Redux] looking at about 110 sites of my interest (thermal sciences) and have an account in Lijit, although haven’t used it extensively yet.

References

1. http://unrulednotebook.wordpress.com/2008/02/20/open-access-publishing/

2. http://unrulednotebook.wordpress.com/2008/06/14/myths-of-and-urgency-for-open-access-journals/

3. http://unrulednotebook.wordpress.com/links

Categories: Academics

What a waste of intellect and ink

October 19, 2007 · 1 Comment

For this Friday’s re-review of Shri. SVK’s review, we first focus our attention on the similarities of the muddle in two of his reviews, appearing in the same day’s newspaper.The first of his review on Lakshmi Rangarajan begins thus

How well with ease her felicitous and appealing voice carried her musical mind marked the concert of Lakshmi Rangarajan in the T.T.Devasthanam’s Navaratri series. Soothing calmness reflected her refined vision in raga alapanas and rendering of songs. There was a caressing content in her sleek presentation.

Now in a second review on vainika Revathy Krishna he begins

The excellence of Revathy Krishna’s performing style rested on how with ease her fingers on the frets and her melodic meettu subserved the subtleties of veena. Her technique in this respect lay in the way she reflected her perceived aesthetic expressions on the instrument.

Her play stood for gentle, persuasive, soothing calmness, her refined vision echoing through alapanas and rendering of kirtanas. This factor contributed in her recital at the Krishna Gana Sabha Gokulashtami series to delineation of the poetic sensitivity couched in sleek presentation.

A short note on the similarities on the above two beginning paragraphs:

1) identical starting sentences (“how well…”) with only the sentence constructions trying to differentiate one review from the other.

2) Use of the ridiculous “soothing calmness”. I have lamented earlier about this trademark of Shri. SVK, the use of inappropriate juxtaposition of double adjectives. For instance, soothing means “to bring peace, composure, or quietude” and calmness means “free from agitation, excitement, or disturbance”. So what is conveyed by a “soothing calmness”?

3) Use of “sleek presentation” – while Lakshmi had a caressing content in it, Revathi couched a “poetic sensitivity” in it.

4) Notice one more thing here: the use of “poetic sensitivity” while praising (describing?) a veena – a string instrument – concert. Like you, I am curious to know what sort of babel fish Shri. SVK had swallowed to discern the music from a stringed instrument to contain (or not) the elusive component of “poetic sensitivity”.

I strongly suspect Shri. SVK has a few templates of English paragraphs that he has honed over the years, stashed in the mixed jolna bag that he carries along with him to every concert. Upon coming out of a concert – attended in full or in parts – he shuffles randomly these pre-laid paragraphs of verbose review content, promptly inserting the songs, concert performers and sabha names appropriate to that day and shoots of one or many review(s) next day to the Hindu.

One of these days, I am sure he could submit (and successfully defend) a dissertation to the London School of Music titled, “An Algorithmic Approach to Carnatic Music Review in Victorian English” – of course, second in style only to that of Thiruvalar Vairamuthu, as noted by Mahadevan Ramesh, father of all Internet Indian Student Humor.

Let me proceed with the second paragraph of the Lakshmi Rangarajan concert review

Exceptionally feminine in measuring the lyrical dimensions of ragas, the delineations revealed the essential difference between skill and flamboyance.

I don’t know about you, but I need a support to steady my nerves to comprehend what that single sentence could mean, leave alone what it actually does. For instance, how is one to measure the “lyrical dimension” of a raga? Agreed, a raga may not be made of one or two or three dimensions. Agreed it could not even get defined on a Lobochaveskian space-time continuum or on the n-dimensional hyperspace conceived by over imaginative arm chair mathematicians, like those lurking in the Matscience or the Raman Research Institute. But to measure the raga using a “lyrical dimension”? Only Lakshmi Rangarajan can do it, in the imagination of Shri. SVK.

Further, she not only measures the raga in lyrical dimensions, she does it in an unique way. An “exceptionally feminine” way – as it is normal of others to measure the raga in a lyrical dimension through a mediocre feminine way, or, say, a poor, botched-up eunuch way.

Now, having read the first part of that sentence, one would be temped to assume from that muddle that Shri. SVK is vaguely praising Lakshmi Rangarajan. But lo! There lies the devious deception and delectable cunning of the verbiage of SVK.

The next part of the sentence is a “revealed the essential difference between skill and flamboyance.” One is always stumped of such a remarkably well directed googly of a sentence as having read that sentence in full, one is now left to wonder whether the singing of Lakshmi Rangarajan is skill-full or flamboyant or both or neither and whether all these are essential while giving a Carnatic music concert.

I can go on, but I shall stop.

Before I end,  if you are a music fan reading my re-reviews of the reviews of SVK (God save you), you might even be tempted to collar me and ask “What else do you think one should write in music reviews?”

To make one of my points let me stop this re-review of Lakshmi Rangarajan’s review and take sample paragraphs from the other Revathy Krishna review by Shri. SVK.

Revathy Krishna’s temperament in the alapana of Thodi and following ragamalika tanam served to project herself as a vainika dedicated to give distinction and respectful dignity to veena.

She achieved this role with effectiveness and aesthetics moving hand-in-hand. Here, the contact between manodharma and reposefulness was intact – an image of one with a superior faculty to perceive sukham in music.

The kirtana she played was ‘Vaaridi Neeku’ from Prahlada Bhakta Vijayam in Tillaisthanam patantharam.

Although one is tempted to take the usual dig at the “respectful dignity” in the first paragraph, let me refrain from doing it. Notice the last paragraph.

Shri. SVK mentions a “Tillaisthanam patantharam”. His discerning ear could observe this subtlety in the kirthana delivery from a Veena. I for one – an average carnatic music listener – is now curious to know what is this “Tillaisthanam patantharam”. Isn’t it the duty of an educated and trained reviewer (who is paid to do his reviews for a national newspaper) of the stature of Shri. SVK to explain it to me in his review space?

Instead of all the disproportionate, often misplaced grandiloquence and polysyllabic muddle that is his review (notice the middle paragraph in the above quote), why can’t this knowledgeable gentleman concentrate on educating the audience on the important objective, to be appreciated, aspects of Carnatic music – our sacred and remarkable heritage?

What a waste of intellect and ink.

Categories: Carnatic Music · Muse
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