The Mechanical-vs-Metallurgy “Branch-Jumping” Issue—Part III: A Couple of Stunning Papers

0. The earlier posts in this series may be found here [^] and here [^].

In this post, I am going to talk about two stunning papers.

1. The First Paper:

Before coming to the paper itself, let me discuss its background a bit.

The paper has a topical relevance to the current news; its subject matter in a way refers to those most unfortunate accidents on the Mumbai-Pune Expressway.

In the recent times, there has been a spate of one particular kind of accidents on the Expressway: a tire of a car (or of a tempo or even a container truck) suddenly bursts open, the car gets out of control, crosses over the median and lands in a lane on the opposite side of the traffic, and ends up having a head-on collision.

People have been discussing the matters, building awareness campaigns, trying to analyze causes. For instance, things like: over-speeding as the cause of the tires bursting open; the absence of a tall enough separating wall on either sides; and human factors such as loss of concentration, drunk-driving, etc.

It’s a fact that on the Expressway most every car exceeds the speed limit (of 80 km/hr). You can see many amateur YouTube videos of passenger buses and ordinary passenger cars registering 120–140 km/hr as a routine. BTW, while watching these videos, notice that in India we drive on the left-hand side, and so, the fastest traffic is (usually!) to be found in the rightmost lane.

When a car unfortunately develops a burst tire and lands up on the other side of the road, not only is it the fastest moving car in the forward direction but also the cars in whose path it lands up after crossing over the median, also happen to be the fastest moving ones on the opposite side. Thus, collisions can possibly occur at, say, 100 + 120 = 220 km/hr (even after discounting the reduction in speed during the crossover, say, from 140 to 100 km/hr), making the situation far more grave. Contrast this situation with that of a car moving at 80 km/hr in the left-most lane. Even if the driver loses control and the car veers on the left-hand side, it still collides on to the protective railing (having quite a bit of capacity to absorb the impact energy) at only, say, 60–70 km/hr. The difference of speeds in a head-on collision is, thus, three times over. Little wonder the percentage of fatalities in this kind of accidents has been so high.

Then, there are issues like the lights of the cars on the opposite side shining directly in your eyes, because there are no shades, no dividing walls that are high enough.

Though I am not at all an expert here, another issue I am toying with is the development of a peculiarly wavy kind of surface due to the combined effects of rolling and vibrations,  especially as caused by heavy weight container trucks travelling on a road. A similar effect can be seen also on the railway tracks, where a wavy profile gets developed. However, in the case of the rails, due to the homogeneity of the material, it becomes a somewhat simpler problem to analyse within a mechanics framework. Even then, let me tell you, it’s a very complex problem to analyse. IIT Kanpur, for instance, has been conducing research sponsored by railways on this problem for many years, and one could say that they are still in a somewhat early modelling stage. Now, when it comes to a steel-reinforced cement-concrete road, it becomes, from the applied mechanics viewpoint, a much more complex problem to model. When the road is made of concrete, I am guessing, the peaks of the wavy profile could perhaps be a bit a too sharp, thereby introducing enhanced high frequency components in the car-road interactions, vibrations and what effectively are small-scale but high-speed impacts. Now, if the tires are worn out and are conventional (i.e. if they carry tubes and are not of the tubeless variety), and if a driver has been over-speeding for a long time thereby overheating them, especially on this kind of a more sharply wavy surface, there could be increased chances of the tube of the tire bursting open. (The tubeless tires have a tendency to more gracefully handle an event of a similar kind; the running out of the air or nitrogen is less intense and not so catastrophic.)

So, people have been talking of things like that, and, as you can see, I too have joined them, wondering aloud about what possibly could be the causes of such accidents.

Against this backdrop, here is a paper I found in a recent Web search:

N. P. Dharmadhikari, D. C. Meshram, S. D. Kulkarni, S. M. Hambarde, A. P. Rao, S. S. Pimplikar, A. G. Kharat, and P. T. Patil (2010) “Geopathic stress: a study to understand its nature using Light Interference Technique,” Current Science, vol. 98, no. 5, pp. 695–697

I must say that the paper is simply stunning.

Check it for yourself, and if you think otherwise, do drop me a line. I am sure, though, that you, too, would find it simply stunning. Especially noticeable is the level of rigor in both experimentation and the kind of data that have been gathered therein. Do have a look.

I gather that “Current Science” is “the [sic] leading interdisciplinary science journal from India […] started in 1932 by the then stalwarts of Indian science such as CV Raman, Birbal Sahni, Meghnad Saha, Martin Foster and S.S. Bhatnagar.” I also gather that it is indexed in “Web of Science, Current Contents, Geobase, Chemical Abstracts, IndMed and Scopus” [^].

BTW, the fact that the journal is indexed by so many services, esp. Scopus, goes to satisfy the requirements clarified by Professor Dr. T. P. Singh (Director, Symbiosis Institute of Technology). Recently, in an informal chat, he had mentioned to me that he cannot hire me because I do not have two journal papers already published, and so, I cannot become a PhD guide at Symbiosis from day 1. He then added that it is now his requirement to hire only those people as Full Professors who have two papers published in Scopus/similar indexed journals already, so that they can become PhD guides right from day 1 (his emphasis) and then, he continued in the same conversation, that during the last semester (when I too had applied at Symbiosis) he had hired two people as Full Professors but without PhD degrees so they cannot act as PhD guides from day 1 (here, the emphasis is mine). BTW, at the time that he hired those two people, I, too, had applied for the same post (having PhD already in hand), but was not called for interview at all. … Yes, sometimes Prof. Singh somehow has a charming way of reminding me of the late Jaspal Bhatti, an engineer.

Anyway, coming back to this paper, please note, engineering college professors from JSPM, MIT and Sinhagad have participated in it. There are as many as 7 authors to this paper. (Isn’t this fact stunning by itself?) They all, I suppose, have been approved by the UGC committees for recruitment of professors. In fact, this research began with a PhD granted by the University of Pune, in the first place.

BTW, if you are interested, here is another article which carries more or less the same level of rigor but it is definitely much more readable: [^].

2. The Second Paper:

Another paper, too, has a bit of a topical importance, at least as far as this blog is concerned, in the light of the recent discussion on the Fourier theory and all.

The paper in question is this:

G. K. Kharate, V. H. Patil and N. L. Bhale (2007) “Selection of mother wavelet for image compression on basis of nature of image,” Journal of Multimedia, vol. 2, no. 6, pp. 44–51

This paper, too, is stunning.

Why do I find it stunning?

In this paper, the authors experimentally study the extent to which different types of images can be compressed, using wavelets transforms. In particular, the extent of compression that is possible for a natural image (a woman’s portrait) is compared and contrasted with certain artificial images consisting of simple regular patterns such as horizontal/vertical/oblique lines. The conclusions reached by the authors consist of the following:

“The results demonstrate that for line-based image percentage of zeros is more for db1 as compared to other wavelets and more energy is retained. It shows that the loss of information is less hence the quality is better. Also for natural image percentage of zeros is more for db4 as compared to other wavelets that indicates more compression and the loss of information is less.

If the import of the conclusion is not immediately clear, here are a few passages from the main text of the paper that may help you in ascertaining the nature of the paper:

“It is observed that for periodic functions, Fourier analysis is ideal. However, wavelet transforms are not restricted to only the periodic function, but for any function, provided it is admissible.”

I was left wondering: How about the computational complexity of FFT vis-a-vis wavelets—particularly because the paper deals with compression efficiency? Reading further on, I then saw this:

“We suggest the minimum two steps for the wavelet decomposition. In first step, decompose the image by using any mother wavelet. On the basis of energy content of approximation and detail coefficients, the image is [first] classified as line image or natural image. Then select the proper mother wavelet for further decompositions as mentioned above.” [Emphasis in bold is mine.]

How about entropy? Well, this aspect is not as clearly indicated.

The Journal of Multimedia is, of course, an international journal published from the USA; it is indexed in many services, including Scopus [^].

Anyway, the first author is the current Dean of the Faculty of Engineering at the University of Pune. I mean to say: he was first awarded a doctorate in engineering by the University of Pune (under the guidance of A. A. Ghatol); he was selected by a UGC committee for a Full Professor’s position; he was also democratically elected by the professors coming from all the engineering colleges affiliated to the university of Pune; he now sits on the UGC interview committees that decide whether someone (e.g. me) is to be at all interviewed or not.

Do note that it’s not his the then PhD student (i.e. V. H. Patil), but Kharate himself who is the first author of this paper. Not so stunning. Not any more.

But, yes, the paper, overall, is stunning. Its conclusion simply has a way to force you to do a double take. Its very appearance is against what you expect intuitively—you never expect a paper of this kind to appear in a typical journal covering topics such as multimedia, image or signal processing, or wavelets analysis.

As you might know, the wavelets transform is similar to the Fourier transform though it has a categorically less computational cost involved with it as compared to FFT. Also, take a moment to think about what kind of connections could at all be possible between computational complexity, information entropy and the compression efficiency.

Now, reconsider the cited text and the conclusion of this paper.

Hopefully, now you can see why I say that you must read this journal paper, too.

* * * * *    * * * * *   * * * * *   

BTW, I have finally been rejected in the interviewing process at the JPBTI Phaneesh Murthy’s company, iGATE. The reason communicated to me (over the phone) by Asad Kadri this late evening had to do with the fact that I don’t have documentary evidence for having actually done jobs at three places: (i) Mukand (in 1983), and (ii) Thermax (in 1983–84); at both these places I was a trainee engineer; and then, (iii) QueriSoft (in 1995–96 i.e. about 15+ years ago), a company which is closed by now. BTW, I had arranged for a former colleague to informally verify the fact of my having worked with Querisoft, and anyway did have a xerox copy of the appointment letter for it. However, iGATE apparently thinks that their end-client, Rio Tinto, would find it unacceptable that all of my employment cannot be verified. In any case, they didn’t reply back to that email written by that past colleague of mine (who later on worked as a director in a large American MNC, and has now taken voluntary retirement from the IT field).

On my part, I find both Rio Tinto and iGATE to be very funny companies—tinted, as if they were, with a very dogged and out-of-the-world sort of a sense of humour. (They took three months, two interviews with the VP, three interviews with HR, and many telephonic calls and emails exchanges, in order to reach the conclusion that they cannot appoint me because I do not carry experience certificates for companies where I worked two decades ago and more.)

So, my job search continues, and something on the academia side might materialize—something that allows me at least, say, survival. I will keep you posted.

… But, don’t forget only to see those two papers, na!

* * * * *    * * * * *   * * * * *  

A Song I Like:
[For the above-mentioned reasons, the inclusion this time round of this section is, once again, purely on the whim.]

(Hindi) “machalti hui hawaa main chham chham…” (“hamare sang sang chalein Ganga ki leheren”)
Singers: Kishore Kumar [an unlikely choice, esp. given early ’60s], and Lata Mangeshkar
Music: Chitragupt
Lyrics: Majrooh Sultanpuri [?]

[E&OE]

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The Mechanical-vs-Metallurgy “Branch-Jumping” Issue—Part II: Not Attending Inter-/Multi-/Trans-Disciplinary Conferences

0. To know the context and the primary intended readership of this post, please see my earlier post in this series, here: [^]. Of course, as mentioned earlier, everyone else is welcome to read this series, too.

1. The 57th (annual) Congress of the Indian Society of Theoretical and Applied Mechanics (An International Meet) was held at Pune this week, from 17th through 20th December, 2012 [^]. The venue was the Defence Institute of Advanced Technology (now a deemed university) [^]. (Caveat: Their Web site is often down, and with the PDF documents almost always missing. For example, try to download their faculty recruitment form.) I attended it, but this time round, without presenting any paper.

2. The conference was inaugurated by Dr. V. K. Saraswat [^], himself a PhD in combustion engineering. [Yes, the stupid primary intended readership [see part I to know exactly who all], this too is a topic common to both metallurgy and mechanical engineering.] The inaugural and valedictory functions were presided over by Dr. Prahlada [^], the vice-chancellor of the host institute (DIAT).

3. Some 180 papers were presented in the parallel sessions, many of them of multi-/trans-/inter-disciplinary nature, and with their authors coming from almost all departments of science and engineering. Even including electronics engineering, and mining engineering, apart from, of course, the usual ones: applied mechanics, mechanical engg., aerospace engg., civil engg., metallurgical/materials engg., mathematics, physics and astrophysics.

4. Even going just by my personal informal observations, people came to this conference from a lot of places: Guwahati, Kharagpur, Coimbatore, Kanpur, Chennai, Bangalore, Visakhapattanam, Hyderabad, Gulbarga, Surat, Mumbai, etc.

The foreign participation was somewhat limited this time round, with just a couple of Americans (both of Indian origin, both well-honored HoDs of mechanical or mechanics departments), and, off-hand, I suppose, one or two leading researchers or professors each from Canada, Germany, Israel, Japan, Taiwan, etc.

But, come, they did.

In contrast, the IIT Bombay QIP PhD D. W. Pande (of mechanical engineering branch from Aurangabad, now lording over at COEP); the meteorology (?) PhD degree holder G. B. Pant (sitting on the board of governors of COEP [a new addition to the stupid intended readership that should have been effected right the last time, and I will explain the reason for his inclusion the next time]); the Dean of the Faculty of Engineering of the University of Pune, PhD degree holder Gajanan Kharate (from Amaravati, now lording over at Pune, and per government, perhaps an OBC); his PhD guide the IIT Bombay QIP PhD Ashok A. Ghatol (formerly, Director, COEP, per government, certainly an OBC) did not come. Neither any of the others of their ilk.

Not even if they all are employed, and even if the places of their employment are all in or around Pune, and the conference was held right in Pune. [And that being academics, they would get discounts for the conference registration fees, and being government/university employed etc., they would get the conference fee refunded back anyway. Unlike me, who borrowed Rs. 3,500/- to attend it. Despite all that discount and its refunds, these characters still did not attend.]

And, of course, they didn’t send a single student of theirs to attend this conference either. Forget for paper presentation, not even for plain attendance.

The acceptance rate this time round was a bit higher, at about 60%. In the earlier ISTAMs which I attended, it has been 50% and lower; in fact, perhaps as low as 33% (if not 25%, but I don’t remember it too well, so let’s say, 33%). Pretty decent. Better than many reputed international journals. Even then, they still didn’t send a single student. [And, I am sure, this evil + stupid primary intended readership, while evaluating my employment application, would immediately pounce on the fact that I have no journal paper to my credit, only conference papers—if they could get past this metallurgy-to-mechanical “branch-jump” issue.]

These stupid idiots (and possibly evil characters—remember, free will as the basis of morality) with government-assured jobs and pensions and prestige, perhaps realized that if they attended the ISTAM conference, they might run into inter-/multi-/trans-disciplinary researches in mechanics and mechanical engineering. They perhaps also further realized that such a fact might then run counter to the one specific belief they fondly cuddle, cherish, openly advocate, defend and profess, and unhesitatingly act on: namely, that metallurgical graduates with PhD in mechanical cannot teach in or be hired by mechanical departments.

5. As to the research presented in the conference, much of it was not related to my current interests. But still, getting to know about the topics that other people are working on, the ideas they are pursuing, is always intellectually invigorating. I would like to write about the research part separately. Research, in fact any productive work, is such a noble thing. In contrast, for this post, I would not like to dilute the intensity of the focus on my joblessness due to the downright stupidity/evil of these above-mentioned professors/directors/government’s son in laws, etc.

However, I guess I could still mention just a couple of things in the passing.

5.1 One was the mention of the infinite speed of propagation of heat flux in conduction, during the invited lecture by Prof. I. Chung Liu of the National Chi Nan University, Taiwan. (I involuntarily sat up straight from my habitual slump while sitting in that cozy main auditorium at DIAT.) The approach Prof. Liu began with, was already known to me from my arXiv browsing. [No, the stupid intended readership of Mechanical Engineering Professors, Deans and Directors etc., arXiv usually does not have mechanical engineering related articles. So, you need not bother with this research any further, going by your government-funded and -enforced “logic.”] This approach consists of having a hyperbolic equation (the telegrapher’s equation) in place of the usual parabolic one. These days, a fairly neat Wiki page also exists to explain this approach; see here [^]. After his talk, I walked up to him and tried to explain how a particles-based approach makes it possible to remove the instantaneous action at a distance (IAD). However, Prof. Liu was not very well conversant with the Brownian movement/Weiner processes, and so, I could not pursue the conversation further. I just passingly mentioned my own research on diffusion equation to him. [The stupid primary intended readership of government-funded Mechanical Engineering Professors, University Deans and Directors etc., wouldn’t be able to make out why the IAD at all is an issue in the first place. They wouldn’t be able to make out even after being explicitly told twice.] Anyway, even if very brief, this discussion with Prof. Liu did help bring up some of my own thoughts. There is a certain paper on diffusion equation by a Berkeley professor which I had discovered after publishing my paper, and I would like to discuss it. Guess I will write a post at iMechanica (and, naturally, also here) about it, before sending a revised paper on this topic to a journal.

5.2 The second thing was this idea that had struck me while teaching a course on FEM to the COEP undergraduates in Spring 2009. [Yes, stupid/evil intended readership, I did teach the students of the mechanical branch as well, but only as a visiting faculty, and only for one semester. I was not repeated, despite very good student feedback [which Prof. Anil Sahasrabudhe, Director, COEP, didn’t quite share with me, unlike with his practice with other professors, but I do surmise with some pretty good basis—the direct feedback of students to me–that even my official student evaluation/feedback must have been pretty good.]] The idea is concerning finding a physical interpretation for the method of weighted residuals (MWR)—or, at the least, connecting some more mathematical context to MWR, anyway. My idea being too premature, I had not shared it with these undergraduate students back then. However, since the MTech-level students are a bit more mature, I did briefly hint at it while teaching the course on FEM at Symbiosis this year.

SPOILER ALERT: I may write a paper on this idea.

The idea is this: It first struck me that there was some kind of an analog between fitting a straight line to a scatter plot (say, the least-squares fit), and the method of weighted residuals. Sure, the first is an algebraic system and the second one involves differential equations. (Even if the ansatz is algebraic (a polynomial), before getting to the residuals, you still have to differentiate it, thereby changing the nature of the game.) The algebraic vs the infinitesimal is a big difference, and it is there. Yet, the idea of a residual (and setting it to zero) is common.

Then, I recalled that it was basically the same guy who had thought of both of these ideas, at least in their seed form: C. F. Gauss. (Ok, off-hand, I think that the least squares had already been used by someone else, before Gauss, but Gauss reinvented it independently, anyway. (Turns out, that earlier guy was Legendre [^])). The fact that the same mind had invented both the techniques helped gain more confidence in this idea of treating something like the least squares as an analog of the MWR.

In this conference, I got a chance to sound out this idea to two senior professors of mathematics: Prof. Kaloni of University of Windsor, and Prof. Rathish Kumar of IIT Kanpur. Specifically, I asked them if someone had already worked out something following, say, a function spaces-based approach.

Here, I was trying very hard to recall my earlier general reading decades ago concerning topological interpretation of the differentiation operation and all, and its recent mention by Prof. Tim Poston in a brief communication that I had with him. (It was a point which I had not at all understood at all.) Now at this conference, while talking in the hallways and all, I was trying to recollect those words. But somehow, in the hustle and bustle of the conference and the very short time available for those lounge/hall discussions, I could not recall any of such words. So, I tossed the first word I could catch hold of: function spaces.

Prof. Kaloni thought that someone must have worked on it already. In contrast, Prof. Rathish Kumar raised an entirely different point: where is convergence on the algebraic side of it, he asked. According to him, MWR was not limited to just getting to the residual and setting its domain integral to zero. The essence of MWR also had to include the idea of convergence—of a (possibly infinite) sequence of steps, of a systematic process of reducing the discretization error. In contrast, on the algebraic side of it, he observed, it’s just a one-time affair: you just take the fit, and that’s it. There is nothing more to be done; there is no second step; there is no sequence; the idea of convergence doesn’t apply.

In the busy-ness of such sideways discussions, there was no time to explain that I could get (i.e. I already was thinking of) an algebraic system that can still involve the ideas of convergence. In fact, I thought about it and got at an example right on the fly. But I was sure I couldn’t have explained it in the right words—the idea just flashed right during the conversation. So, not to waste his time, I asked him what would he think of it if I could get such a system (a multi-step, converging but algebraic system), and try to establish an analog with the differential equations-involving MWR. He then said that perhaps such a thing has not been done before, and that it would be nice to have a connection like that formally worked out. [I will repeat this part in a separate post, also at iMechanica, but in the meanwhile, if you know that someone has already worked out something along these lines, please drop me a line; thanks in advance.]

So there. The stupid/evil primary intended readership, these discussions, per your government-funded and government-enforced “logic,” had nothing to do with mechanical engineering. After all, both the professors were from the department of mathematics. So, you the stupid/evil primary intended readership (consisting of folks like G. K. Kharate, A. A. Ghatol, D. W. Pande, G. B. Pant, their friends, etc.), you all sit cozy and quiet and keep on drawing your respective 6th-pay commission-enhanced salaries, allowances, refunds, etc. Keep faithfully doing that, you stupids/idiots/evils.

[I remain jobless; the “A Song I Like” section is once again being dropped.]

[E&OE]