Recycling slideware

In my years at HP I have produced a very large corpus of slideware. The sad part of this is that unlike papers, slides are ephemeral artifacts discarded after a single use. I write sad, because a lot of effort goes into the production of a slide deck, especially in industry, where there are strict design rules and everything has to be "high-concept".

In the past I was posting my formal external presentations in my publications web page, as a link in each conference paper reference. This was useful for people finding my publications using a search engine, but now people use more specialized search tools and then find my publications in the digital libraries of various learned societies in whose conferences the work was presented. These digital libraries do not contain slides because they are informal.

There is a service that allows you to recycle your slides. It is called slideshare and allows you to upload your slides for conversion in to Flash objects that can be embedded. Probably the most logical place to embed your slides is your LinkedIn profile, were people in your social network can discover them, download them, and reuse them.

You can also embed the slides in your blog, like here a presentation I gave in September:

Cognitive Aspects of Color

View SlideShare presentation or Upload your own. (tags: color_names color_dictionary)

As you can see, you can quickly browse the slide deck right here in the blog. If you want to reuse some or all of it, you can click on the title above the slide. This takes you to the slideshare page, from where you can download the presentation.

As you may note, some functionality gets lost in the conversion from PDF to Flash, like the navigation labels in the slide headers. However this is a minor detail. Because the slides are on slideshare's site, you can embed as many slide decks as you want in a post, without burdening your blog platform.

For example, here is my trusty old slide deck on Understanding Color:

Understanding Color

View SlideShare presentation or Upload your own. (tags: color_science short_course)

As you see here, the QuickTime movies are not embedded, but the link on the slides is more convenient anyway, because you can prepare the movies in QuickTime players and show them from there.

Of course, a simple slide deck like this one on MPEG-21 carries over as is:

Introduction to MPEG21

View SlideShare presentation or Upload your own. (tags: mpeg mpeg21)

By the way, each of these slide decks was produced with a different authoring tool. The color cognition deck was produced using the fancy Beamer document class in LaTeX, the introduction to color in the antiquated but robust FrameMaker document preparation system, and the MPEG-21 deck was written in PowerPoint.

The future of electronic paper

The Web site "The Future of Things" has an interesting page on the future of electronic paper. It has interviews with Nick Sheridon of Xerox PARC resp. Gyricon and Till Moor from Siemens. Many photographs show prototypes developed in the laboratories of various companies active in this field. The link is http://thefutureofthings.com/articles/1000/the-future-of-electronic-paper.html.

Pigeons missing in action

It used to be that when traveling you had to bring to your hosts presents from your place of origin. This custom is known in many cultures and words like souvernir or おみやげ (omiyage) have been absorbed in many other languages.

Today this is no longer meaningful, because the concept of exotic has disappeared. This is due to the science of logistics, which has made the transportation of goods so efficient that now you can buy everything everywhere and at the same price.

Despite the miracles of modern logistics, it has a point of failure: the operators follow the instructions of computers, and even if goods are tracked at every step, they can disappear when an unanticipated event occurs.

For example, on September 17 I gave a presentation on color cognition and promised to send a printed copy of Nathan Moroney's color thesaurus and the presentation handout for the asking. When I returned home, I ordered the prints from MagCloud and mailed them to the interested parties.

Unfortunately, the envelopes never arrived. Because the recipients where in different countries, I can be certain that the snafu must have happened before the mail was sorted, i.e., between the mail stop near my cubicle and the United States Postal Service Processing and Distribution Center in San Francisco.

I did stamp the envelopes as air mail. Maybe a confused logistics operator strapped the envelopes on carrier pigeons… Were the carrier pigeon then hijacked in the San Francisco Bay and kidnapped to Eyl?

In fact, most of the time logistics operators do not know what they are doing. They are just trained to blindly and efficiently follow the procedures dictated by the logistics computer. This is one of the tenets of the anorexic company — there are no provisions for the unanticipated or even for incertitude. Immediate action must be taken, regardless of whether it makes sense.

Maybe two countries are a little better off: Japan and Switzerland, where workers are expected to always use their brains when they work (possibly with an exception here in Martigny, where many a brain has become yogurt from boozing Fendant). This is achieved through the concept of the apprenticeship, where future workers are employed as trainees in their future profession while also attending vocational school to develop a theoretical understanding of their chosen profession.

At the Federal Institute of Technology in Lausanne (EPFL) the DUAL-T project in the field of computer-supported collaborative learning has recently delivered to the Centre Professionel du Nord Vaudois (CPNV) this system to train logistics apprentices:

Some smart young people indeed! Should I have carried the envelopes to Martigny and mailed them from here? Not necessarily, because the logistics at SFO or LAX could have lost my suitcases there.

So, if you come across some lost carrier pigeons with a color thesaurus, please energize them and send them along their way…

Social Signal Processing

From Eats Shoots & Leaves by Lynne Tuss we know the importance of punctuation and that occasionally it can be a matter of life and death. However, in some cases punctuation cannot come to our rescue.

Such is the case for social signal processing or SSP. We all know what signal processing is, namely the analysis, interpretation, and manipulation of signals. (Incidentally, in our case the signals of interest are color images.) So is social signal processing a European form of socialized processing of images, like social medicine?

In social signal processing the adjective is not social but social signal — it is about the processing of social signals. What makes this confusing is that many of the researchers in this area are signal processing experts. In view of this, the alternate name of social signals understanding is maybe more appropriate.

SSP is concerned with the machine analysis of social behavior. It is a branch of interactive multimodal information management and studies non-verbal behavioral cues and social behavior. Recently SSPNET, a new Network of Excellence funded under work programme topic ICT-2007.2.2 of the European Commission's Seventh Framework Programme, has been funded.

Just imagine yourself one day sitting in front of a financial advisor to talk about your retirement savings and consulting an application on your smart-phone that can assess if you are talking to a snake in a suit…

Publishing in the cloud

In research the old principle of publishing or perishing has long been replaced by the more quantitative performance metric of publishing in journals with a high impact factor. For example, in the case of the last paper on which I am a coauthor (today papers rarely have a single author, you could not keep up with ranking and funding if you would do that), we did not look which journal is the best fit for our paper.

Instead, we compiled a list of journals that would potentially publish our paper given its subject matter and the importance of its contribution to the advancement of science. Then we sorted the list by impact factor and submitted the manuscript to the New Journal of Physics, with impact factor 3.264. We are obviously very objective and our manuscript will go through a second round after revision, so we picked the correct journal.

Being at the end of my tour of duty as associate editor for a journal with impact factor 0.757, I am very aware of the current bad trend of shopping one's manuscript. In this trend a manuscript is submitted to a top tier journal like Nature (28.751) or Science (26.372) and then submitted again and again to journals with lower impact factor until it is no longer rejected.

Not only does this tax the system by requiring many unnecessary reviews (handling a rejected paper costs about $500, which are not offset by page charges and download fees), but it backfires when a reviewer gets the same manuscript though a different journal. In fact, a good associate editor will seek reviewers that are most familiar with the research described in the paper, so two different associate editors from two different journals will draw on the same small set of potential reviewers. The manuscript then gets rejected as a resubmission of an old manuscript.

It is important to understand that the impact factor is a relative quantity. For example, the Cancer Journal for Clinicians has an impact factor of 69.026, but this does not mean that at 0.757 my journal sucks. On the contrary, compared to other journals in the field it performs quite well. For example its sister journal from the same publisher has an impact factor of 0.455 and that of an other society comes out at 0.220. These journals tend not to publish many survey papers, which inflate the impact factor.

Message 1: use the impact factor with a grain of salt.

As my wife says, even if you win the rat race, you are still just a rat. In reality, today you do not need an impact factor to make an impact. While we can dream of publishing in Science and winning the Nobel Prize (or the Judd Award for us color scientists), today we can shower our incremental knowledge onto humanity with publishing media like personal web sites and blogs. You are reading this post, proving it works!

Granted, it is very informal, but there are some easy steps up. The traditional better medium is the technical report, which can be freely downloaded from the institution's web site, like HPL-2008-109 in the case of my most recent collaboration with co-blogger Nathan Moroney.

For those who want to publish something more glossy, HP Labs is incubating MagCloud, which will satisfy all your vanity requirements. From this link your can order the same technical report, but this time printed on heavy glossy stock and laid out nicely in InDesign instead of LaTeX.

There is even a cloud service to publish the slides of your public presentations. For example, we wrote the above report in the Beamer class, which lays out the same content in a format suitable for overhead projectors (called beamers in German). You can then make available your slides on Slide Share, or even embed them in your blog, like so: http://www.slideshare.net/berettag/cognitive-aspects-of-color-presentation

Finally, since in these difficult economic times everybody is jumping on LinkedIn, you can use a LinkedIn application to post your slides directly on your profile page.

Message 2: use informal media to give impact to your research.

Pushing needles

In my last post Now you see it, now you don't, I passed on the editor's summary of an experiment to research how the brain can combine different views of an object into a single object representation. The researchers inserted needles in the inferior temporal cortex of two monkeys and recorded neurons while the monkeys saccaded to an extra-foveal symbol while the symbol was changed during the saccade.

Reading it like that, pushing needles into the cortex sounds pretty scary, but in reality it is not. Thirty years ago a friend of mine was working for his postdoc with a troglodyte to find the pathway from the visual cortex to the arm's motoric control when a banana was presented. The troglodyte was not in discomfort and actually happily outlived Dr. Gisin, who died at a young age from a brain tumor.

Although Dr. Gisin's team developed a relation with their subject, the problem with such experiments is that we cannot really know what the monkey is thinking. At that time, it would not have been ethically possible to use humans for the experiments. However, in the 30 years since, the medical technology has progressed so much that needles are used clinically to excite neurons in patients with acute forms of diseases like Parkinson's and epilepsy.

Compared to exciting neurons, just recording from them is a minor invasion. Thus data from experiments piggy-backing on clinical procedures are starting to become available. The quantum leap with human subjects is that they can describe what they are thinking.

In Internally Generated Reactivation of Single Neurons in Human Hippocampus During Free Recall, published in Science 3 October 2008: Vol. 322. no. 5898, pp. 96 - 101, a team from UCLA and the Weizman Institute report on recordings from epileptic patients during clinical procedures. In short, they were able to determine that in the hippocampus the neurons are reactivated in the same pattern when a person sees a scene and when the person recalls the scene.

Thus, when we reason on the model of what is happening in the world outside our body, we are in the same state as when we actively scan and analyze the outside world. We cannot immediately discriminate between what we see and what we recall. This is the basis for such effects as memory color.

This is why in general, preferred color reproduction yields more pleasing images than colorimetric color reproduction. And this is also one of the things that makes color science such a challenging discipline.

Here is the Science editor's summary of the report:

The neural correlates of remembering can only be studied with complete confidence in humans, because the subjects can verbally report their internal experience. Brain surgery in which therapeutic electrodes are implanted in the brain of patients with intractable epilepsy provides an opportunity for doing such studies. Gelbard-Sagiv et al. report that neurons in and near the hippocampus of these patients showed specific patterns of activation for each episode of the television show The Simpsons. Later, when these same episodes were brought to mind by free recollection, the same pattern of neural activity was seen, demonstrating that, at least in the hippocampus, recall of a stimulus is accompanied by activation of the same neurons that were activated during the initial experience.

Now you see it, now you don't

Each object can cast many different images on the eye. How can the brain combine different views of an object into a single object representation? Neurons at the inferior temporal cortex (brain area IT), the top processing level of the visual system, signal the presence of individual objects even if those objects appear in different positions.

Nuo Li and James J. DiCarlo in a report in Science Vol. 321, pp.1502-1507 recorded neuronal responses in area IT of two monkeys to different objects presented at the central position and 3 degrees above or below. By systematically swapping object identity between two objects whenever the monkey made a fast eye movement (saccade) to one particular position in the visual field, the response of the IT neuron became less selective to the objects at the swap position or even inverted its selectivity. Thus, object representations in area IT can change in a short period of time.

Have scanner, will travel

Recently, our reader Dan B. from Google sent a link to an article about Prof. Kent A. Kiehl he read in Science magazine Vol. 321 pp. 1284-1286 (also available here). Prof. Kiehl did his graduate work with Prof. Robert Hare at the University of British Columbia in Vancouver, whom you know from his book Snakes in Suits I reviewed over a year ago.

Actually, in that post I displayed this image, which is from Prof. Kiehl's work.

In that post I wrote jokingly that we color scientists have an advantage over the general population because in case of a suspicious colleague we could use a modified version of the color naming experiment to unmask them, or we could walk down the hall to a colleague with an fMRI machine and collaborate on an experiment.

The Science magazine article describes how Prof. Kiehl is actually doing just that. With a custom-built mobile functional magnetic resonance imaging (fMRI) scanner — roughly $2.3 million of equipment packed into a 15-meter-long trailer — and permission from the New Mexico governor to work in all 12 state prisons, Kiehl aims to scan 1000 inmates a year.

Kiehl's research is funded by four R01 grants from the National Institutes of Health, which pay about $900,000 a year in direct costs; the Mind Research Network (MRN) at the University of New Mexico in Albuquerque paid for the scanner.

The reason for recruiting the subjects in the state prisons is that these are places where it is easy to find them. However, if Prof. Kiehl would start his research project today, he might have chosen a different venue and population. In fact, In Snakes in Suits Prof. Hare and Dr. Bobiak describe in detail the evolution to the transitioning organization and present the concept of entrepreneurial pretenders.

The book cited several instances of such entrepreneurial pretenders in the saving & loans crisis and Enron. If one follows the news, one might suspect Manhattan is a biotope where Prof. Kiehl might find an abundance of subjects to study.

Speaking about the news from Manhattan, in an earlier post I blogged about how the end of communism and the cold war made the concept of outbraining the communists obsolete and started the demise of scientific think tanks. If one believes the news, one might think we are currently witnessing the end of capitalism, with the widespread nationalization of financial institutions.

This might bring a new era where it is no longer about being number one, but just about working and making a contribution to society. And this might not require think tanks, in the view of our leaders. In fact, the latest issue of Science magazine has a news item by Laura Margottini on Italy Restricts Academic Hires, in which it is reported that academic hiring is being severely cut back and institutions should look for private sponsors. Apparently it will not be the western hemisphere who will dig world economics out of the current hole with new science and technology. We will have to look elsewhere.

Experiments supporting the concept of a g(2)-camera

Last weekend, as like an astronaut in a Mercury capsule I sat strapped in a small seat in a metal tube being flung across the Atlantic and Canada's Northern Territories, I was reading the day's press from both sides of the Atlantic to catch up with the last two weeks of news and get an appreciation of the reality field's distortions.

On both sides of the Atlantic, physicists made first page news, but for very different reasons, as you would expect in a Riemannian reality field. In the US newspaper, a journalist had been chasing so-called financial geniuses in New York and London to get the rap on $700 billion of toxic financial papers. In the European newspapers the story was on page four, with the question of why the US Government was talking about $700 billion when the actual amount of toxic paper was $3,500 billion, or $3,500,000,000,000.00.

Anyway, that is what you get with reality distortion, but it was not what caught my attention. The journalists were not able to get any financial genius to speak on the record, so they reported remarks from both sides of the Atlantic stating that the financial instruments were so complex that there was no way they (the geniuses) could understand them, that is why they hired quantum mechanics physicists to cook up risk models.

So, there it was written black on white: the quantum mechanics physicists are to blame for the $3,500 billion toxic papers. Hmm, and I thought the only toxic paper quantum physicists handle is that in the litter box of Schrödinger's cat. And they can even not known if the cat is dead or alive.

The story about the quantum physicists would have been more believable, if they had written the $3,500 billion disappeared in a black hole when the Large Hadron Collider (LHC) was turned on in Geneva (see this article on page 1291 of Science magazine of 5 September 2008).

That is what I read in the US newspapers. In the European newspapers physicists made the first page for completely different reasons. The first reason was the LHC. There had been some apprehension about black holes, but the operation start on 10 September was a full success. Unfortunately, over a week later, a possible faulty electrical connection between two of the accelerator’s magnets caused a large helium leak into sector 3-4, moving the start of the experiments to March 2009.

What the newspapers explained in some detail, was how beneficial the $8 billions spent on the LHC was for European industry, because it spurred a large amount of new technology in fields like superconductors and low-temperature materials. While I was reading this, I thought, wow, $8 << $3,500 billion. We could have had our own supercollider in Texas for only the bonuses of one bank in one year!?

The second front page news related to physics in European newspapers was Zhai Zhigang's space walk and the impact the development of the Shenzhou 7 capsule and its launching technology had on Chinese industry, leading it to develop more advanced technologies.

As a whole, from a European perspective, quantum physics and rocket science are not as bad as it is believed to be on this side of the Atlantic. From an international point of view, that had already been decided in the Nüremberg trials, which lets me continue with the meat of this post without shame.

It did not make the newspapers, but last week our paper on experiments supporting the concept of a g(2)-camera was published. If your institution does not subscribe to SPIE's Digital Library, you can buy it for only $18.00 (those are plain dollars, not billions).

Recent experiments have reported the Bose-Einstein condensation (BEC) phase transition for exciton-polariton systems in a semiconductor microcavity. The macroscopic quantum degeneracy is typically detected by probing the statistical properties of light emitted from a microcavity, under the presumption that the statistics of the exciton polaritons are faithfully transferred to the emanating photons.

The macroscopic quantum degeneracy can be established by measuring the correlations viz., first-order in the electric fields:

and seconds-order in the electric fields:

Moreover, it has been assumed that observation of the interference fringes similar to those in Michelson or Young interferometers is sufficient to establish the fact of macroscopic coherence in exciton-polariton systems. Two points on the wave front separated by a distance x₁₂ produce an intensity pattern

such that the fringe visibility measures the magnitude of the first-order correlation function g⁽¹⁾(x₁₂, τ). But simply measuring this quantity alone is ambiguous because a coherent light source (e.g., a photon laser or decaying polariton BEC) can exhibit the same first-order correlations as a chaotic (or thermal) light source (e.g. Hg-Ar discharge lamp). The table below shows that proper disambiguation of a coherent state also requires measurement of the second-order correlation function

associated with intensity noise correlations. Here, I_1,2(t) is the light intensity at a point ±½ x₁₂ and time t.

Maximal values of respective correlation functions for incoherent, coherent and thermal light states

correlation function	photon states
	incoherent	coherent	chaotic
g(1)(x, 0)	0	1	1
g(2)(x, 0)	1	1	2
∆g(2)(x, 0)	0	0	1

The minimal condition to confirm the BEC phase transition in a polariton system then becomes

Our imager detects the spatial correlation excess shown as ∆g⁽²⁾ ≡ g⁽²⁾(x, 0) – 1 in the third row of the table above.

In our paper, we present a novel g⁽²⁾-imager built with conventional CMOS technology, which is capable of measuring second-order spatio-temporal correlated photons and thereby offers an important means for verifying the existence of a BEC state of cavity exciton polaritons.

One potential limitation when imaging BECs with our device is the requirement that ∆g⁽²⁾ = 0, which corresponds to a null measurement. For BEC detection, however, we anticipate that a more practical device could combine conventional g⁽¹⁾-imaging with g⁽²⁾-imaging, either as the same camera operated in two distinct modes or as two distinct cameras working together.

Future work will include the development of larger arrays of SPADs, the integration of on-chip data processing based on equation

and the extension to other g⁽²⁾-imaging applications.

A surprising feature of the g⁽²⁾-camera is that the parallelism of the sensor stemming from using N detectors does not scale linearly but binomially. For example with a 4 x 4 SPAD array all 16 detectors have separate parallel outputs so that (¹⁶₂) = 120 simultaneous pairwise measurements are possible.

You can get the full paper from this link: http://spie.org/x648.xml?product_id=795166.

That branch of Lake Como, which turns south

The airport in Frankfurt is an enclosed space where everybody comes from at least a thousand kilometers from the next person and speaks a radically different language. The planners made it all work by abstracting the semiotic common ground of humanity. The operators make it all work with a perfectly executed clockwork.

What a different experience getting off the airplane in Malpensa. Everybody looks the same and speaks the same language with the same accent. And while an hour earlier in Frankfurt it was silent like in a mausoleum, in Malpensa it is busy and loud like in a bazar.

Everybody seems to have two cell phones, one ringing and the other being used to exchange trivialities with remote people. And people keep talking to everybody around them. Sure, unlike the people in Frankfurt, these people can. But strangers keep asking me when their suitcase will come out, how long it will take, where they will have to go next…

I place myself under the carousel's display, where I can just rise my finger and point to the display. What do I know? Later, driving to the hotel, my host Prof. Rizzi explains me that I witnessed the Italian version of the GPS: you just constantly ask the people around you for directions. I guess that works in a society where most people walk.

The autostrada takes some getting used to, when one normally cruises on 101 or 280. But then, everybody is watching — no spaced out people juggling a coffee mug in one hand and a cell phone in the other. And there is not the heavy metal protection of an SUV.

We arrive at the hotel for the invited keynote speakers. I am surprised. The Comaschi, the people from Como, especially the business people, are known for having short arms (meaning they cannot easily reach in their pockets to take out their bill-fold). Yet, here they put us up in the best hotel in town.

Not only, they put us in the best rooms in the best best hotel in town. What a view! As you see in the pictures, in front of us is that branch of Como Lake, which turns south, between two uninterrupted mountain chains, all peninsulas and bays, depending on their sticking out or caving in, becomes, all the sudden, constricted, and becoming like a river…

Quel ramo del lago di Como, che volge a mezzogiorno, tra due catene non interrotte di monti, tutto a seni e a golfi, a seconda dello sporgere e del rientrare di quelli, vien, quasi a un tratto, a ristringersi, e a prender corso e figura di fiume, tra un promontorio a destra, e un'ampia costiera dall'altra parte; e il ponte, che ivi congiunge le due rive, par che renda ancor più sensibile all'occhio questa trasformazione, e segni il punto in cui il lago cessa, e l'Adda rincomincia, per ripigliar poi nome di lago dove le rive, allontanandosi di nuovo, lascian l'acqua distendersi e rallentarsi in nuovi golfi e in nuovi seni.

What a suffering it was in middle school, and what a gorgeous sight it is now.

When we arrive at the conference venue, we find a mixture of preoccupation, panic, and emergency. The proceedings did not arrive, and nobody knows who is in charge. Only the badges for people at the beginning and end of the alphabet are here, the others are missing. There is no wireless, where is IT? The janitor does not know. Short rapid conversations.

Then everybody pulls out their two cell phones. Is it high noon? No, every person in the hallways is communicating simultaneously on each of ten channels: the first cell phone in one hand talking to one person, the other cell phone in the other hand talking to a second person, both phones announcing the arrival of an SMS after another, talking to several people in the room, and orchestrating the hole gesticulating with the hands. What a cacophony!

Suddenly people start showing up. "Good afternoon, I am the one for the coffee." "Good afternoon, I am the IT manager." And so on. Everybody is proposing a contribution. What is amazing to somebody accustomed to the American way of doing business is that there are no negotiations, no power games, no delays to talk things over with the boss.

Everybody only makes positive proposals. Everybody has personal authority to make decisions. Numbering systems and spreadsheets are set up so there is full accountability on everything. After less than two hours the whole conference has been organized on the spot and everybody is satisfied that it is better than they had anticipated. It is time to part because it will be a long evening and night to get everything done to perfection.

It comes to my mind that everybody here in middle school has learned Nicolò Macchiavelli's Prince and knows how to manage well. In fact, here the whole Prince is summarized in the few lines of a vernacular haiku:

fin che ga né…

viva el re…

Quand ghe né pü…

crepa l'asan e quel che gh'é sù.

Mr. Bill Hewlett would have added "and we do not need any stinking Voice of the Workforce surveys."