"Network coding is studied when an adversary controls a subset of nodes in the network of limited quantity but unknown location. This problem is shown to be more difficult than when the adversary controls a given number of edges in the network, in that linear codes are insufficient. To solve the node problem, the class of Polytope Codes is introduced. Polytope Codes are constant composition codes operating over bounded polytopes in integer vector fields. The polytope structure creates additional complexity, but it induces properties on marginal distributions of code vectors so that validities of codewords can be checked by internal nodes of the network. It is shown that Polytope Codes achieve a cut-set bound for a class of planar networks. It is also shown that this cut-set bound is not always tight, and a tighter bound is given for an example network."

"A good visualization conveys key information to those who may have trouble interpreting numbers and/or statistics, which can make your findings accessible to a wider audience (more on this below).  Visualizations also give your audience a break from lexical processing, which is especially useful when you are presenting your findings–people can listen to you and process the findings from a well-designed visual at the same time, but most people have trouble listening while reading your PowerPoint bullet points.  Visualizations also convey key information embedded in massive amounts of data, which can aid your own exploratory analysis of data, no matter how massive."

A community of agents is subject to a stream of messages, which are represented as points on a plane of issues. Messages are sent by media and by agents themselves. Messages from media shape the public opinion. They are unbiased, i.e. positive and negative opinions on a given issue appear with equal frequencies. In our previous work, the only criterion to receive a message by an agent is if the distance between this message and the ones received earlier does not exceed the given value of the tolerance parameter. Here we introduce a possibility to address a message to a given neighbour. We show that this option reduces the unanimity effect, what improves the collective performance.

"This work is devoted to communication approaches, which spread information in robot swarms. These mechanisms are useful for large-scale systems and also for such cases when a limited communication equipment does not allow routing of information packages. We focus on two approaches such as virtual fields and epidemic algorithms, discuss several aspects of hardware implementation and demonstrate experiments performed with microrobots "Jasmine"."

"Distributed data aggregation has been an active field of research in the last decade, and a huge diverse amount of techniques can be found in the literature. For this reasons, this survey intends to be an important time saving instrument, for those that desire to get a quick and comprehensive overview of the state of the art on distributed data aggregation. Moreover, by carefully highlighting the strength and limitations of the more pertinent approaches, this study can provide a useful assistance to help readers choose which technique to apply in specific settings.

Currently, there is no ideal general solution to the distributed computation of an aggregation function, all existing techniques have its pitfalls (some more than others). Therefore, more research in this field will be expected in the next few years. In particular, due to the added value of computing complex aggregates, new algorithms might arise to estimate the statistical distribution of values, as the few existing approaches exhibit some limitations in terms of accuracy and resource consumption. Additional research efforts should be made to improve the support to churn, message loss, and continuous estimation of mutable input values."

"To counter this trend, and to encourage collaboration in the workplace, we built an internal tool called Lunch Roulette that selects random pairs of Fellows to join each other on impromptu lunch dates.…"

We get mistaken for graduate students: I had to field questions along the lines of “so who do you work with?” for at least 10 years after Ph.D. We get interrupted, talked over or ignored in conversation. When we disagree with our male colleagues, especially on administrative matters, we’re presumed to be mistaken until proved otherwise. In collaborations, we’re assumed to be the lesser participants far more often than we’re assumed to be the leaders. In situations that require a compromise, the “reasonable” expectation is for us to meet the other party about 4/5 of the way, if not farther.

"Zipf's law seems to be ubiquitous in human languages and appears to be a universal property of complex communicating systems. Following an early proposal made by Zipf concerning the presence of a tension between the efforts of speaker and hearer in a communication system, we introduce evolution by means of a variational approach to the problem based on Kullback's Minimum Discrimination of Information Principle. Using a formalism fully embedded in the framework of information theory, we demonstrate that Zipf's law is the only expected outcome of an evolving, communicative system under a rigorous definition of the communicative tension described by Zipf."

"Recovery of the sparsity pattern (or support) of a sparse vector from a small number of noisy linear samples is a common problem that arises in signal processing and statistics. In the high dimensional setting, it is known that recovery with a vanishing fraction of errors is impossible if the sampling rate and per-sample signal-to-noise ratio (SNR) are finite constants independent of the length of the vector. In this paper, it is shown that recovery with an arbitrarily small but constant fraction of errors is, however, possible, and that in some cases a computationally simple thresholding estimator is near-optimal.…"

"To our knowledge, the two most prominent aspects of our setting, the presence of asymmetric information and the stationarity requirement (stemming from unknown start times) have not been considered in the literature. For example, the Anderson-Weber strategy for the telephone problem is not stationary — it has a period of n − 1. It would be interesting to see what can be said about the optimal stationary strategies for this and other rendezvous problems. The interested reader is referred to [2,3] and the references therein for more information on rendezvous search games."

"Actually, the snarXiv only gen er ates tan ta liz ing titles and abstracts at the moment, while the arXiv deliv ers match ing papers as well. Details of the implemen ta tion are below.[2] I’m the author, and I don’t remem ber exactly why I decided to do this. I did already have the frame work lying around from a pre vi ous project, and I swear I spent more time doing research last week end than imple ment ing snarXiv.org."

"With some modifications, the proof movie can be used as the data structure underlying an encyclopedia that we envisage containing formal proofs together with an informal narrative explanation, and provide a toolbox for using and manipulating such composite “articles”…"

"Think of it this way: if having your development team work this way through sprints, why not board notes? Meeting every 6-8 weeks with no interim communication is like the waterfall software development process!"

"So it probably would not take much for politicians to be persuaded that the press is essential to democracy, and that its survival ... depends on government support. Advertising revenue would be replaced by government subsidies, raising predictable questions about the impact on content.
The alternative is to focus on what communication technology cannot do: create rather than transmit a good story or a good policy. There will always be a market for quality. The disruption caused by emerging communications technologies consists in the fact that the best pens may not be on the staffs of newspapers, and that policies need not be formulated only in the corridors of government."

"In the age of mass media, the press was able to define the sphere of legitimate debate with relative ease because the people on the receiving end were atomized-- connected "up" to Big Media but not across to each other. And now that authority is eroding. I will try to explain why.
It’s easily the most useful diagram I’ve found for understanding the practice of journalism in the United States, and the hidden politics of that practice. You can draw it by hand right now. Take a sheet of paper and make a big circle in the middle. In the center of that circle draw a smaller one to create a doughnut shape. Label the doughnut hole “sphere of consensus.” Call the middle region “sphere of legitimate debate,” and the outer region “sphere of deviance.”"

"Solving the current problems in science communication requires the intervention of strong companies such as Google. But it will take more than technical advances to provoke scientists into taking full advantage of the web. We need pressure, and perhaps compulsion, from journals and funders to raise publishing standards to the new level made possible by such tools. Google Wave may not be, indeed is probably not, the whole answer. But it points the way to tools that build records and reproducibility into every step. And that has to be good for science."

Be sure to look at the background and silhouetted wires in this shot. See the comment, "That's one of the most amazing collections of overhead wires I've ever seen on Shorpy. I'll bet that it has a lot to do with the business on the ground floor of our featured building."

"We need context in order to live, and if the environment of electronic communication has stopped providing it, we shouldn't search online for a solution but turn back to the real world and slow down. To do this, we need to uncouple our idea of progress from speed, separate the idea of speed from effi ciency, pause and step back enough to realize that efficiency may be good for business and governments but does not always lead to mindfulness and sustainable, rewarding relationships. We are here for a short time on this planet, and reacting to demands on our time by simply speeding up has canceled out many of the benefits of the Internet, which is one of the most fabulous technological inventions ever conceived. We are connected, yes, but we were before, only by gossamer threads that worked more slowly. Slow communication will preserve these threads and our ability to sensibly choose to use faster modes when necessary…."

"Teasley's current research focuses on the social and cognitive processes in collaboration. She researches technology use to support key aspects of collaboration for both co-located groups and distributed groups. She has extensive experience assessing work practices and user needs, and designing, implementing, and evaluating technology use. She has conducted her work in schools, Fortune 500 companies, and with the biomedical community where she has helped to support the scientific activity in several distributed research centers. She is also involved in the development and evaluation of collaborative tools for academic research and teaching in higher education. "

"I study the building of bridges, wikis in organizations, and interventions with newly hired employees in order to understand how distributed work gets done and how social computing technologies are engaged in that work. I'm especially interested in learning that takes place when people work together. I aim to contribute new ways of thinking about distributed work, learning in collaboration, and the roles of social computing in both. "

"The art of conversation, with its counterpart the dialogue as a literary form for presenting ideas, has also declined since the days of Galileo, while the art of advertising has advanced. Advertising is easily recognized as the literary form that most completely responds to the technique of the printing press, because it demands, above all else, a numerous and receptive "public" of readers. A great number of improvements in the graphic arts have been adaptations to the needs of advertisers. Yet, in its development of "direct mail" methods and circular letters, advertising seems to be more emancipated than literature from the printing press. One of the most curious recent developments in the graphic arts is the effort of the advertisers to make printed matter look like typescript, while the authors of books that are not in sufficient demand to warrant publication are seeking a typescript that will look like print."

"Throughout the trip, we met with a diverse group of sustainability luminaries, including global systems scientist Will Steffen, Australian Minister for Environment, Heritage and the Arts (and former Midnight Oil frontman) Peter Garrett, Aboriginal activist Isabelle Coe and sustainability guru Phillip Sutton. Though their areas of expertise varied, they expressed a common interest in finding new ways for individuals to think and collaborate for the sake of the 'whole.'"

"In a scientific context what does this mean? The overall project referred to is your analysis. The activities are simple operations within your analysis. All these operations have a certain number of inputs and outputs. In the case of fetching a DNA sequence, an input may be an identifier of the sequence, whilst the output is a string representing the nucleotide sequence represented by this identifier.
The triggering of activities by other activities are where an operation feeds data into a subsequent operation. For example, the ‘fetch sequence’ operation may feed its output (the string containing sequence ‘ACTG’) into a ‘transcribe’ operation. This would subsequently change the DNA sequence into an RNA sequence. We would then have a simple workflow with one operation, and a link, which looks something like the following:..."

"The Mechanics’ Institute sprang up in 19th century England for the ostensible purpose of imparting upon the working class mechanic knowledge of the sciences, literature, and arts. In actuality, a myriad of purposes shrouded the creation of these institutes, which were ultimately appropriated by the middle class when it became apparent that the working class was not as receptive as had been anticipated. ... As the middle class began to move in, the working class retreated to the Institute’s libraries and reading rooms, where they were free to discuss topics that interested them. One of the unintended consequences of the failed Mechanics’ Institutes was the aiding in the creation of a democratic infrastructure for working class access to printed materials.... In short, despite being borne from a desire to regulate, they were an important precursor to the establishment of public libraries and a liberated mass reading public."

An excellent talk on testing legacy code. Some great insights on how to use judicious refactoring and contingent testing. Not too Ruby-specific.

"Tell people what you need: OK, this one seems like it should be pretty obvious, but I'm starting here because this is where far too many people miss the boat. Whether it's for fear of imposing or being told no, or a feeling that they should be able to "do it themselves," the biggest mistake people make when it comes to helping people help them is not asking."

Graham describes his strategy precisely: "Find (a) simple solutions (b) to overlooked problems (c) that actually need to be solved, and (d) deliver them as informally as possible, (e) starting with a very crude version 1, then (f) iterating rapidly." That seems simple, but it is not. He elaborates:

When I first laid out these principles explicitly, I noticed something striking: this is practically a recipe for generating a contemptuous initial reaction. Though simple solutions are better, they don't seem as impressive as complex ones.

"We must embrace and encourage abundance and not let ourselves be captive of an artificial marketplace that is unable to sustain itself in the face of any competition."

Do not design for yourself. Other people are not yourself.

via: Making Light

via:Sivacracy

Wiki-editing a Masters Thesis, live.

Another live thesis editing experiment.