The science papers I've read

Today I read a paper titled “Social Networks and Spin Glasses”

The abstract is:
The networks formed from the links between telephones observed in a month’s call detail records (CDRs) in the UK are analyzed, looking for the characteristics thought to identify a communications network or a social network.

Some novel methods are employed.

We find similarities to both types of network.

We conclude that, just as analogies to spin glasses have proved fruitful for optimization of large scale practical problems, there will be opportunities to exploit a statistical mechanics of the formation and dynamics of social networks in today’s electronically connected world.

Today I read a paper titled “Entropy-based Tuning of Musical Instruments”

The abstract is:
The human sense of hearing perceives a combination of sounds ‘in tune’ if the corresponding harmonic spectra are correlated, meaning that the neuronal excitation pattern in the inner ear exhibits some kind of order.

Based on this observation it is suggested that musical instruments such as pianos can be tuned by minimizing the Shannon entropy of suitably preprocessed Fourier spectra.

This method reproduces not only the correct stretch curve but also similar pitch fluctuations as in the case of high-quality aural tuning.

Today I read a paper titled “Acoustic Communication for Medical Nanorobots”

The abstract is:
Communication among microscopic robots (nanorobots) can coordinate their activities for biomedical tasks.

The feasibility of in vivo ultrasonic communication is evaluated for micron-size robots broadcasting into various types of tissues.

Frequencies between 10MHz and 300MHz give the best tradeoff between efficient acoustic generation and attenuation for communication over distances of about 100 microns.

Based on these results, we find power available from ambient oxygen and glucose in the bloodstream can readily support communication rates of about 10,000 bits/second between micron-sized robots.

We discuss techniques, such as directional acoustic beams, that can increase this rate.

The acoustic pressure fields enabling this communication are unlikely to damage nearby tissue, and short bursts at considerably higher power could be of therapeutic use.

Today I read a paper titled “Multi-command Tactile and Auditory Brain Computer Interface based on Head Position Stimulation”

The abstract is:
We study the extent to which vibrotactile stimuli delivered to the head of a subject can serve as a platform for a brain computer interface (BCI) paradigm.

Six head positions are used to evoke combined somatosensory and auditory (via the bone conduction effect) brain responses, in order to define a multimodal tactile and auditory brain computer interface (taBCI).

Experimental results of subjects performing online taBCI, using stimuli with a moderately fast inter-stimulus interval (ISI), validate the taBCI paradigm, while the feasibility of the concept is illuminated through information transfer rate case studies.

Today I read a paper titled “An Innovative Scheme For Effectual Fingerprint Data Compression Using Bezier Curve Representations”

The abstract is:
Naturally, with the mounting application of biometric systems, there arises a difficulty in storing and handling those acquired biometric data.

Fingerprint recognition has been recognized as one of the most mature and established technique among all the biometrics systems.

In recent times, with fingerprint recognition receiving increasingly more attention the amount of fingerprints collected has been constantly creating enormous problems in storage and transmission.

Henceforth, the compression of fingerprints has emerged as an indispensable step in automated fingerprint recognition systems.

Several researchers have presented approaches for fingerprint image compression.

In this paper, we propose a novel and efficient scheme for fingerprint image compression.

The presented scheme utilizes the Bezier curve representations for effective compression of fingerprint images.

Initially, the ridges present in the fingerprint image are extracted along with their coordinate values using the approach presented.

Subsequently, the control points are determined for all the ridges by visualizing each ridge as a Bezier curve.

The control points of all the ridges determined are stored and are used to represent the fingerprint image.

When needed, the fingerprint image is reconstructed from the stored control points using Bezier curves.

The quality of the reconstructed fingerprint is determined by a formal evaluation.

The proposed scheme achieves considerable memory reduction in storing the fingerprint.

Today I read a paper titled “Delays Induce an Exponential Memory Gap for Rendezvous in Trees”

The abstract is:
The aim of rendezvous in a graph is meeting of two mobile agents at some node of an unknown anonymous connected graph.

In this paper, we focus on rendezvous in trees, and, analogously to the efforts that have been made for solving the exploration problem with compact automata, we study the size of memory of mobile agents that permits to solve the rendezvous problem deterministically.

We assume that the agents are identical, and move in synchronous rounds.

We first show that if the delay between the starting times of the agents is arbitrary, then the lower bound on memory required for rendezvous is Omega(log n) bits, even for the line of length n.

This lower bound meets a previously known upper bound of O(log n) bits for rendezvous in arbitrary graphs of size at most n.

Our main result is a proof that the amount of memory needed for rendezvous with simultaneous start depends essentially on the number L of leaves of the tree, and is exponentially less impacted by the number n of nodes.

Indeed, we present two identical agents with O(log L + loglog n) bits of memory that solve the rendezvous problem in all trees with at most n nodes and at most L leaves.

Hence, for the class of trees with polylogarithmically many leaves, there is an exponential gap in minimum memory size needed for rendezvous between the scenario with arbitrary delay and the scenario with delay zero.

Moreover, we show that our upper bound is optimal by proving that Omega(log L + loglog n)$ bits of memory are required for rendezvous, even in the class of trees with degrees bounded by 3.

Today I read a paper titled “A Theory of Consciousness Founded on Neurons That Behave Like Qubits”

The abstract is:
This paper presents a hypothesis that consciousness is a natural result of neurons that become connected recursively, and work synchronously between short and long term memories.

Such neurons demonstrate qubit-like properties, each supporting a probabilistic combination of true and false at a given phase.

Advantages of qubits include probabilistic modifications of cues for searching associations in long term memory, and controlled toggling for parallel, reversible computations to prioritize multiple recalls and to facilitate mathematical abilities.

Today I read a paper titled “Nearest Neighbor Value Interpolation”

The abstract is:
This paper presents the nearest neighbor value (NNV) algorithm for high resolution (H.R.) image interpolation.

The difference between the proposed algorithm and conventional nearest neighbor algorithm is that the concept applied, to estimate the missing pixel value, is guided by the nearest value rather than the distance.

In other words, the proposed concept selects one pixel, among four directly surrounding the empty location, whose value is almost equal to the value generated by the conventional bilinear interpolation algorithm.

The proposed method demonstrated higher performances in terms of H.R.

when compared to the conventional interpolation algorithms mentioned.

Today I read a paper titled “Shopping Uncertainties in a Mobile and Social Context”

The abstract is:
We conducted a qualitative user study with 77 consumers to investigate what social aspects are relevant when supporting customers during their shopping activities and particularly in situations when they are undecided.

Twenty-five respondents (32%) reported seeking extra information on web pages and forums, in addition to asking their peers for advice (related to the nature of the item to be bought).

Moreover, from the remaining 52 subjects, only 6 (8%) were confident enough to make prompt comparisons between items and an immediate purchasing choice, while 17 respondents (22%) expressed the need for being away from persuasive elements.

The remaining 29 respondents (38%) reported having a suboptimal strategy for making their shopping decisions (i.e.

buying all items, not buying, or choosing randomly).

Therefore, the majority of our participants (70% = 32% + 38%) had social and information needs when making purchasing decisions.

This result motivates the development of applications that would allow consumers to ask shopping questions to their social network while on-the-go.

Today I read a paper titled “Q#, a quantum computation package for the .NET platform”

The abstract is:
Quantum computing is a promising approach of computation that is based on equations from Quantum Mechanics.

A simulator for quantum algorithms must be capable of performing heavy mathematical matrix transforms.

The design of the simulator itself takes one of three forms: Quantum Turing Machine, Network Model or circuit model of connected gates or, Quantum Programming Language, yet, some simulators are hybrid.

We studied previous simulators and then we adopt features from three simulators of different implementation languages, different paradigms, and for different platforms.

They are Quantum Computing Language (QCL), QUASI, and Quantum Optics Toolbox for Matlab 5.

Our simulator for quantum algorithms takes the form of a package or a programming library for Quantum computing, with a case study showing the ability of using it in the circuit model.

The .NET is a promising platform for computing.

VB.NET is an easy, high productive programming language with the full power and functionality provided by the .NET framework.

It is highly readable, writeable, and flexible language, compared to another language such as C#.NET in many aspects.

We adopted VB.NET although its shortage in built-in mathematical complex and matrix operations, compared to Matlab.

For implementation, we first built a mathematical core of matrix operations.

Then, we built a quantum core which contains: basic qubits and register operations, basic 1D, 2D, and 3D quantum gates, and multi-view visualization of the quantum state, then a window for demos to show you how to use and get the most of the package.

Today I read a paper titled “Topological Considerations for Tuning and Fingering Stringed Instruments”

The abstract is:
We present a formal language for assigning pitches to strings for fingered multi-string instruments, particularly the six-string guitar.

Given the instrument’s tuning (the strings’ open pitches) and the compass of the fingers of the hand stopping the strings, the formalism yields a framework for simultaneously optimizing three things: the mapping of pitches to strings, the choice of instrument tuning, and the key of the composition.

Final optimization relies on heuristics idiomatic to the tuning, the particular musical style, and the performer’s proficiency.

Today I read a paper titled “The blogosphere as an excitable social medium: Richter’s and Omori’s Law in media coverage”

The abstract is:
We study the dynamics of public media attention by monitoring the content of online blogs.

Social and media events can be traced by the propagation of word frequencies of related keywords.

Media events are classified as exogenous – where blogging activity is triggered by an external news item – or endogenous where word frequencies build up within a blogging community without external influences.

We show that word occurrences show statistical similarities to earthquakes.

The size distribution of media events follows a Gutenberg-Richter law, the dynamics of media attention before and after the media event follows Omori’s law.

We present further empirical evidence that for media events of endogenous origin the overall public reception of the event is correlated with the behavior of word frequencies at the beginning of the event, and is to a certain degree predictable.

These results may imply that the process of opinion formation in a human society might be related to effects known from excitable media.

Today I read a paper titled “Applying Evolutionary Optimisation to Robot Obstacle Avoidance”

The abstract is:
This paper presents an artificial evolutionbased method for stereo image analysis and its application to real-time obstacle detection and avoidance for a mobile robot.

It uses the Parisian approach, which consists here in splitting the representation of the robot’s environment into a large number of simple primitives, the “flies”, which are evolved following a biologically inspired scheme and give a fast, low-cost solution to the obstacle detection problem in mobile robotics.

Today I read a paper titled “Exploration of Recent Advances in the Field of Brain Computer Interfaces”

The abstract is:
A new approach for implementing number of expressions, emotions and, actions to operate objects through the thoughts of brain using a Non-Invasive Brain Computing Interface (BCI) technique has been proposed.

In this paper a survey on brain and its operations are presented.

The steps involved in the brain signal processing are discussed.

The current systems are able to present few expressions and emotions on a single device.

The proposed system provides the extended number of expressions on multiple numbers of objects.

Today I read a paper titled “Haar Wavelet Based Approach for Image Compression and Quality Assessment of Compressed Image”

The abstract is:
With the increasing growth of technology and the entrance into the digital age, we have to handle a vast amount of information every time which often presents difficulties.

So, the digital information must be stored and retrieved in an efficient and effective manner, in order for it to be put to practical use.

Wavelets provide a mathematical way of encoding information in such a way that it is layered according to level of detail.

This layering facilitates approximations at various intermediate stages.

These approximations can be stored using a lot less space than the original data.

Here a low complex 2D image compression method using wavelets as the basis functions and the approach to measure the quality of the compressed image are presented.

The particular wavelet chosen and used here is the simplest wavelet form namely the Haar Wavelet.

The 2D discret wavelet transform (DWT) has been applied and the detail matrices from the information matrix of the image have been estimated.

The reconstructed image is synthesized using the estimated detail matrices and information matrix provided by the Wavelet transform.

The quality of the compressed images has been evaluated using some factors like Compression Ratio (CR), Peak Signal to Noise Ratio (PSNR), Mean Opinion Score (MOS), Picture Quality Scale (PQS) etc.

Today I read a paper titled “Rendering of 3D Dynamic Virtual Environments”

The abstract is:
In this paper we present a framework for the rendering of dynamic 3D virtual environments which can be integrated in the development of videogames.

It includes methods to manage sounds and particle effects, paged static geometries, the support of a physics engine and various input systems.

It has been designed with a modular structure to allow future expansions.

We exploited some open-source state-of-the-art components such as OGRE, PhysX, ParticleUniverse, etc.; all of them have been properly integrated to obtain peculiar physical and environmental effects.

The stand-alone version of the application is fully compatible with Direct3D and OpenGL APIs and adopts OpenAL APIs to manage audio cards.

Concluding, we devised a showcase demo which reproduces a dynamic 3D environment, including some particular effects: the alternation of day and night infuencing the lighting of the scene, the rendering of terrain, water and vegetation, the reproduction of sounds and atmospheric agents.

Today I read a paper titled “Social Structure of Facebook Networks”

The abstract is:
We study the social structure of Facebook “friendship” networks at one hundred American colleges and universities at a single point in time, and we examine the roles of user attributes – gender, class year, major, high school, and residence – at these institutions.

We investigate the influence of common attributes at the dyad level in terms of assortativity coefficients and regression models.

We then examine larger-scale groupings by detecting communities algorithmically and comparing them to network partitions based on the user characteristics.

We thereby compare the relative importances of different characteristics at different institutions, finding for example that common high school is more important to the social organization of large institutions and that the importance of common major varies significantly between institutions.

Our calculations illustrate how microscopic and macroscopic perspectives give complementary insights on the social organization at universities and suggest future studies to investigate such phenomena further.

Today I read a paper titled “Robust Multi-Robot Optimal Path Planning with Temporal Logic Constraints”

The abstract is:
In this paper we present a method for automatically planning robust optimal paths for a group of robots that satisfy a common high level mission specification.

Each robot’s motion in the environment is modeled as a weighted transition system, and the mission is given as a Linear Temporal Logic (LTL) formula over a set of propositions satisfied by the regions of the environment.

In addition, an optimizing proposition must repeatedly be satisfied.

The goal is to minimize the maximum time between satisfying instances of the optimizing proposition while ensuring that the LTL formula is satisfied even with uncertainty in the robots’ traveling times.

We characterize a class of LTL formulas that are robust to robot timing errors, for which we generate optimal paths if no timing errors are present, and we present bounds on the deviation from the optimal values in the presence of errors.

We implement and experimentally evaluate our method considering a persistent monitoring task in a road network environment.

Today I read a paper titled “Network Archaeology: Uncovering Ancient Networks from Present-day Interactions”

The abstract is:
Often questions arise about old or extinct networks.

What proteins interacted in a long-extinct ancestor species of yeast? Who were the central players in the Last.fm social network 3 years ago? Our ability to answer such questions has been limited by the unavailability of past versions of networks.

To overcome these limitations, we propose several algorithms for reconstructing a network’s history of growth given only the network as it exists today and a generative model by which the network is believed to have evolved.

Our likelihood-based method finds a probable previous state of the network by reversing the forward growth model.

This approach retains node identities so that the history of individual nodes can be tracked.

We apply these algorithms to uncover older, non-extant biological and social networks believed to have grown via several models, including duplication-mutation with complementarity, forest fire, and preferential attachment.

Through experiments on both synthetic and real-world data, we find that our algorithms can estimate node arrival times, identify anchor nodes from which new nodes copy links, and can reveal significant features of networks that have long since disappeared.

Today I read a paper titled “Towards Social Profile Based Overlays”

The abstract is:
Online social networking has quickly become one of the most common activities of Internet users.

As social networks evolve, they encourage users to share more information, requiring the users, in turn, to place more trust into social networks.

Peer-to-peer (P2P) overlays provide an environment that can return ownership of information, trust, and control to the users, away from centralized third-party social networks.

In this paper, we present a novel concept, social profile overlays, which enable users to share their profile only with trusted peers in a scalable, reliable, and private manner.

Each user’s profile consists of a unique private, secure overlay, where members of that overlay have a friendship with the overlay owner.

Profile data is made available without regard to the online state of the profile owner through the use of the profile overlay’s distributed data store.

Privacy and security are enforced through the use of a public key infrastructure (PKI), where the role of certificate authority (CA) is handled by the overlay owner and each member of the overlay has a CA-signed certificate.

All members of the social network join a common public or directory overlay facilitating friend discovery and bootstrap connections into profile overlays.

We define interfaces and present tools that can be used to implement this system, as well as explore some of the challenges related to it.

Today I read a paper titled “Memristor-based Synaptic Networks and Logical Operations Using In-Situ Computing”

The abstract is:
We present new computational building blocks based on memristive devices.

These blocks, can be used to implement either supervised or unsupervised learning modules.

This is achieved using a crosspoint architecture which is an efficient array implementation for nanoscale two-terminal memristive devices.

Based on these blocks and an experimentally verified SPICE macromodel for the memristor, we demonstrate that firstly, the Spike-Timing-Dependent Plasticity (STDP) can be implemented by a single memristor device and secondly, a memristor-based competitive Hebbian learning through STDP using a $1\times 1000$ synaptic network.

This is achieved by adjusting the memristor’s conductance values (weights) as a function of the timing difference between presynaptic and postsynaptic spikes.

These implementations have a number of shortcomings due to the memristor’s characteristics such as memory decay, highly nonlinear switching behaviour as a function of applied voltage/current, and functional uniformity.

These shortcomings can be addressed by utilising a mixed gates that can be used in conjunction with the analogue behaviour for biomimetic computation.

The digital implementations in this paper use in-situ computational capability of the memristor.

Today I read a paper titled “All liaisons are dangerous when all your friends are known to us”

The abstract is:
Online Social Networks (OSNs) are used by millions of users worldwide.

Academically speaking, there is little doubt about the usefulness of demographic studies conducted on OSNs and, hence, methods to label unknown users from small labeled samples are very useful.

However, from the general public point of view, this can be a serious privacy concern.

Thus, both topics are tackled in this paper: First, a new algorithm to perform user profiling in social networks is described, and its performance is reported and discussed.

Secondly, the experiments –conducted on information usually considered sensitive– reveal that by just publicizing one’s contacts privacy is at risk and, thus, measures to minimize privacy leaks due to social graph data mining are outlined.

Today I read a paper titled “Perceiving the Social: A Multi-Agent System to Support Human Navigation in Foreign Communities”

The abstract is:
This paper describes a system developed to help people explore local communities by providing navigation services in social spaces created by the community members via communication and knowledge sharing.

The proposed system utilizes data of a community’s social network to reconstruct the social space, which is otherwise not physically perceptible but imaginary, experiential, yet learnable.

The social space is modeled with an agent network, where each agent stands for a member of the community and has knowledge about expertise and personal characteristics of some other members.

An agent can gather information, using its social “connections”, to find community members most suitable to communicate to in a specific situation defined by the system’s user.

The system then deploys its multimodal interface, which “maps” the social space onto a representation of the relevant physical space, to locate the potential interlocutors and advise the user on an efficient communication strategy for the given community.

Today I read a paper titled “Opinion dynamics of random-walking agents on a lattice”

The abstract is:
Opinion dynamics of random-walking agents on finite two-dimensional lattices is studied.

In the model, the opinion is continuous, and both the lattice and the opinion can be either periodic or non-periodic.

At each time step, all agents move randomly on the lattice, and update their opinions based on those of neighbors with whom the differences of opinions are not greater than a given threshold.

Due to the effect of repeated averaging, opinions first converge locally, and eventually reach steady states.

Like other models with bounded confidence, steady states in general are those with one or more opinion groups, in which all agents have the same opinion.

When both the lattice and the opinion are periodic, however, metastable states, in which the whole spectrum of location-dependent opinions can coexist, can emerge.

This result shows that, when a set of continuous opinions forms a structure like a circle, other that a typically-used linear opinions, rich dynamic behavior can arise.

When there are geographical restrictions in reality, a complete consensus is rarely reached, and metastable states here can be one of the explanations for these situations, especially when opinions are not linear.

Today I read a paper titled “Evaluating Effectiveness of Tamper Proofing on Dynamic Graph Software Watermarks”

The abstract is:
For enhancing the protection level of dynamic graph software watermarks and for the purpose of conducting the analysis which evaluates the effect of integrating two software protection techniques such as software watermarking and tamper proofing, constant encoding technique along with the enhancement through the idea of constant splitting is proposed.

In this paper Thomborson technique has been implemented with the scheme of breaking constants which enables to encode all constants without having any consideration about their values with respect to the value of watermark tree.

Experimental analysis which have been conducted and provided in this paper concludes that the constant encoding process significantly increases the code size, heap space usage, and execution time, while making the tamper proofed code resilient to variety of semantic preserving program transformation attacks.

Today I read a paper titled “Planar Visibility: Testing and Counting”

The abstract is:
In this paper we consider query versions of visibility testing and visibility counting.

Let $S$ be a set of $n$ disjoint line segments in $\R^2$ and let $s$ be an element of $S$.

Visibility testing is to preprocess $S$ so that we can quickly determine if $s$ is visible from a query point $q$.

Visibility counting involves preprocessing $S$ so that one can quickly estimate the number of segments in $S$ visible from a query point $q$.

We present several data structures for the two query problems.

The structures build upon a result by O’Rourke and Suri (1984) who showed that the subset, $V_S(s)$, of $\R^2$ that is weakly visible from a segment $s$ can be represented as the union of a set, $C_S(s)$, of $O(n^2)$ triangles, even though the complexity of $V_S(s)$ can be $\Omega(n^4)$.

We define a variant of their covering, give efficient output-sensitive algorithms for computing it, and prove additional properties needed to obtain approximation bounds.

Some of our bounds rely on a new combinatorial result that relates the number of segments of $S$ visible from a point $p$ to the number of triangles in $\bigcup_{s\in S} C_S(s)$ that contain $p$.

Today I read a paper titled “The Revisiting Problem in Mobile Robot Map Building: A Hierarchical Bayesian Approach”

The abstract is:
We present an application of hierarchical Bayesian estimation to robot map building.

The revisiting problem occurs when a robot has to decide whether it is seeing a previously-built portion of a map, or is exploring new territory.

This is a difficult decision problem, requiring the probability of being outside of the current known map.

To estimate this probability, we model the structure of a “typical” environment as a hidden Markov model that generates sequences of views observed by a robot navigating through the environment.

A Dirichlet prior over structural models is learned from previously explored environments.

Whenever a robot explores a new environment, the posterior over the model is estimated by Dirichlet hyperparameters.

Our approach is implemented and tested in the context of multi-robot map merging, a particularly difficult instance of the revisiting problem.

Experiments with robot data show that the technique yields strong improvements over alternative methods.

Today I read a paper titled “Secure Watermarking Scheme for Color Image Using Intensity of Pixel and LSB Substitution”

The abstract is:
In this paper a novel spatial domain LSB based watermarking scheme for color Images is proposed.

The proposed scheme is of type blind and invisible watermarking.

Our scheme introduces the concept of storing variable number of bits in each pixel based on the actual color value of pixel.

Equal or higher the color value of channels with respect to intensity of pixel stores higher number of watermark bits.

The Red, Green and Blue channel of the color image has been used for watermark embedding.

The watermark is embedded into selected channels of pixel.

The proposed method supports high watermark embedding capacity, which is equivalent to the size of cover image.

The security of watermark is preserved by permuting the watermark bits using secret key.

The proposed scheme is found robust to various image processing operations such as image compression, blurring, salt and pepper noise, filtering and cropping.

Today I read a paper titled “Spatial Domain Watermarking Scheme for Colored Images Based on Log-average Luminance”

The abstract is:
In this paper a new watermarking scheme is presented based on log-average luminance.

A colored-image is divided into blocks after converting the RGB colored image to YCbCr color space.

A monochrome image of 1024 bytes is used as the watermark.

To embed the watermark, 16 blocks of size 8X8 are selected and used to embed the watermark image into the original image.

The selected blocks are chosen spirally (beginning form the center of the image) among the blocks that have log-average luminance higher than or equal the log-average luminance of the entire image.

Each byte of the monochrome watermark is added by updating a luminance value of a pixel of the image.

If the byte of the watermark image represented white color (255) a value is added to the image pixel luminance value, if it is black (0) the is subtracted from the luminance value.

To extract the watermark, the selected blocks are chosen as the above, if the difference between the luminance value of the watermarked image pixel and the original image pixel is greater than 0, the watermark pixel is supposed to be white, otherwise it supposed to be black.

Experimental results show that the proposed scheme is efficient against changing the watermarked image to grayscale, image cropping, and JPEG compression.

Today I read a paper titled “Motif Analysis in the Amazon Product Co-Purchasing Network”

The abstract is:
Online stores like Amazon and Ebay are growing by the day.

Fewer people go to departmental stores as opposed to the convenience of purchasing from stores online.

These stores may employ a number of techniques to advertise and recommend the appropriate product to the appropriate buyer profile.

This article evaluates various 3-node and 4-node motifs occurring in such networks.

Community structures are evaluated too.These results may provide interesting insights into user behavior and a better understanding of marketing techniques.

Today I read a paper titled “Text/Graphics Separation and Skew Correction of Text Regions of Business Card Images for Mobile Devices”

The abstract is:
Separation of the text regions from background texture and graphics is an important step of any optical character recognition system for the images containing both texts and graphics.

In this paper, we have presented a novel text/graphics separation technique and a method for skew correction of text regions extracted from business card images captured with a cell-phone camera.

At first, the background is eliminated at a coarse level based on intensity variance.

This makes the foreground components distinct from each other.

Then the non-text components are removed using various characteristic features of text and graphics.

Finally, the text regions are skew corrected for further processing.

Experimenting with business card images of various resolutions, we have found an optimum performance of 98.25% (recall) with 0.75 MP images, that takes 0.17 seconds processing time and 1.1 MB peak memory on a moderately powerful computer (DualCore 1.73 GHz Processor, 1 GB RAM, 1 MB L2 Cache).

The developed technique is computationally efficient and consumes low memory so as to be applicable on mobile devices.

Today I read a paper titled “Local Space-Time Smoothing for Version Controlled Documents”

The abstract is:
Unlike static documents, version controlled documents are continuously edited by one or more authors.

Such collaborative revision process makes traditional modeling and visualization techniques inappropriate.

In this paper we propose a new representation based on local space-time smoothing that captures important revision patterns.

We demonstrate the applicability of our framework using experiments on synthetic and real-world data.

Today I read a paper titled “Improved visualisation of brain arteriovenous malformations using color intensity projections with hue cycling”

The abstract is:
Color intensity projections (CIPs) have been shown to improve the visualisation of greyscale angiography images by combining greyscale images into a single color image.

A key property of the combined CIPs image is the encoding of the arrival time information from greyscale images into the hue of the color in the CIPs image.

A few minor improvements to the calculation of the CIPs image are introduced that substantially improve the quality of the visualisation.

One improvement is interpolating of the greyscale images in time before calculation of the CIPs image.

A second is the use of hue cycling – where the hue of the color is cycled through more than once in an image.

The hue cycling allows the variation of the hue to be concentrated in structures of interest.

An angiogram of a brain is used to demonstrate the substantial improvements hue cycling brings to CIPs images.

A third improvement is the use of maximum intensity projection for 2D rendering of a 3D CIPs image volume.

A fourth improvement allows interpreters to interactively adjust the phase of the hue via standard contrast-brightness controls using lookup tables.

Other potential applications of CIPs are also mentioned.

Today I read a paper titled “Side-channel attack on labeling CAPTCHAs”

The abstract is:
We propose a new scheme of attack on the Microsoft’s ASIRRA CAPTCHA which represents a significant shortcut to the intended attacking path, as it is not based in any advance in the state of the art on the field of image recognition.

After studying the ASIRRA Public Corpus, we conclude that the security margin as stated by their authors seems to be quite optimistic.

Then, we analyze which of the studied parameters for the image files seems to disclose the most valuable information for helping in correct classification, arriving at a surprising discovery.

This represents a completely new approach to breaking CAPTCHAs that can be applied to many of the currently proposed image-labeling algorithms, and to prove this point we show how to use the very same approach against the HumanAuth CAPTCHA.

Lastly, we investigate some measures that could be used to secure the ASIRRA and HumanAuth schemes, but conclude no easy solutions are at hand.

Today I read a paper titled “Text/Graphics Separation for Business Card Images for Mobile Devices”

The abstract is:
Separation of the text regions from background texture and graphics is an important step of any optical character recognition sytem for the images containg both texts and graphics.

In this paper, we have presented a novel text/graphics separation technique for business card images captured with a cell-phone camera.

At first, the background is eliminated at a coarse level based on intensity variance.

This makes the foreground components distinct from each other.

Then the non-text components are removed using various characteristic features of text and graphics.

Finally, the text regions are skew corrected and binarized for further processing.

Experimenting with business card images of various resolutions, we have found an optimum performance of 98.54% with 0.75 MP images, that takes 0.17 seconds processing time and 1.1 MB peak memory on a moderately powerful computer (DualCore 1.73 GHz Processor, 1 GB RAM, 1 MB L2 Cache).

The developed technique is computationally efficient and consumes low memory so as to be applicable on mobile devices.

Today I read a paper titled “Extended Range Telepresence for Evacuation Training in Pedestrian Simulations”

The abstract is:
In this contribution, we propose a new framework to evaluate pedestrian simula-tions by using Extended Range Telepresence.

Telepresence is used as a virtual reality walking simulator, which provides the user with a realistic impression of being present and walking in a virtual environment that is much larger than the real physical environment, in which the user actually walks.

The validation of the simulation is performed by comparing motion data of the telepresent user with simulated data at some points of the simulation.

The use of haptic feedback from the simulation makes the framework suitable for training in emergency situations.

Today I read a paper titled “Artist Agent: A Reinforcement Learning Approach to Automatic Stroke Generation in Oriental Ink Painting”

The abstract is:
Oriental ink painting, called Sumi-e, is one of the most appealing painting styles that has attracted artists around the world.

Major challenges in computer-based Sumi-e simulation are to abstract complex scene information and draw smooth and natural brush strokes.

To automatically find such strokes, we propose to model the brush as a reinforcement learning agent, and learn desired brush-trajectories by maximizing the sum of rewards in the policy search framework.

We also provide elaborate design of actions, states, and rewards tailored for a Sumi-e agent.

The effectiveness of our proposed approach is demonstrated through simulated Sumi-e experiments.

Today I read a paper titled “Artificial Skin Ridges Enhance Local Tactile Shape Discrimination”

The abstract is:
One of the fundamental requirements for an artificial hand to successfully grasp and manipulate an object is to be able to distinguish different objects’ shapes and, more specifically, the objects’ surface curvatures.

In this study, we investigate the possibility of enhancing the curvature detection of embedded tactile sensors by proposing a ridged fingertip structure, simulating human fingerprints.

In addition, a curvature detection approach based on machine learning methods is proposed to provide the embedded sensors with the ability to discriminate the surface curvature of different objects.

For this purpose, a set of experiments were carried out to collect tactile signals from a 2 \times 2 tactile sensor array, then the signals were processed and used for learning algorithms.

To achieve the best possible performance for our machine learning approach, three different learning algorithms of Na\”ive Bayes (NB), Artificial Neural Networks (ANN), and Support Vector Machines (SVM) were implemented and compared for various parameters.

Finally, the most accurate method was selected to evaluate the proposed skin structure in recognition of three different curvatures.

The results showed an accuracy rate of 97.5% in surface curvature discrimination.

Today I read a paper titled “Trends and Techniques in Visual Gaze Analysis”

The abstract is:
Visualizing gaze data is an effective way for the quick interpretation of eye tracking results.

This paper presents a study investigation benefits and limitations of visual gaze analysis among eye tracking professionals and researchers.

The results were used to create a tool for visual gaze analysis within a Master’s project.

Today I read a paper titled “Social Norms for Online Communities”

The abstract is:
Sustaining cooperation among self-interested agents is critical for the proliferation of emerging online social communities, such as online communities formed through social networking services.

Providing incentives for cooperation in social communities is particularly challenging because of their unique features: a large population of anonymous agents interacting infrequently, having asymmetric interests, and dynamically joining and leaving the community; operation errors; and low-cost reputation whitewashing.

In this paper, taking these features into consideration, we propose a framework for the design and analysis of a class of incentive schemes based on a social norm, which consists of a reputation scheme and a social strategy.

We first define the concept of a sustainable social norm under which every agent has an incentive to follow the social strategy given the reputation scheme.

We then formulate the problem of designing an optimal social norm, which selects a social norm that maximizes overall social welfare among all sustainable social norms.

Using the proposed framework, we study the structure of optimal social norms and the impacts of punishment lengths and whitewashing on optimal social norms.

Our results show that optimal social norms are capable of sustaining cooperation, with the amount of cooperation varying depending on the community characteristics.

Today I read a paper titled “Distributed Self-Organization Of Swarms To Find Globally $ε$-Optimal Routes To Locally Sensed Targets”

The abstract is:
The problem of near-optimal distributed path planning to locally sensed targets is investigated in the context of large swarms.

The proposed algorithm uses only information that can be locally queried, and rigorous theoretical results on convergence, robustness, scalability are established, and effect of system parameters such as the agent-level communication radius and agent velocities on global performance is analyzed.

The fundamental philosophy of the proposed approach is to percolate local information across the swarm, enabling agents to indirectly access the global context.

A gradient emerges, reflecting the performance of agents, computed in a distributed manner via local information exchange between neighboring agents.

It is shown that to follow near-optimal routes to a target which can be only sensed locally, and whose location is not known a priori, the agents need to simply move towards its “best” neighbor, where the notion of “best” is obtained by computing the state-specific language measure of an underlying probabilistic finite state automata.

The theoretical results are validated in high-fidelity simulation experiments, with excess of $10^4$ agents.

Today I read a paper titled “Effects of Initial Stance of Quadruped Trotting on Walking Stability”

The abstract is:
It is very important for quadruped walking machine to keep its stability in high speed walking.

It has been indicated that moment around the supporting diagonal line of quadruped in trotting gait largely influences walking stability.

In this paper, moment around the supporting diagonal line of quadruped in trotting gait is modeled and its effects on body attitude are analyzed.

The degree of influence varies with different initial stances of quadruped and we get the optimal initial stance of quadruped in trotting gait with maximal walking stability.

Simulation results are presented.

Keywords: quadruped, trotting, attitude, walking stability.

Today I read a paper titled “A Proposal for Proquints: Identifiers that are Readable, Spellable, and Pronounceable”

The abstract is:
Identifiers (IDs) are pervasive throughout our modern life.

We suggest that these IDs would be easier to manage and remember if they were easily readable, spellable, and pronounceable.

As a solution to this problem we propose using PRO-nouncable QUINT-uplets of alternating unambiguous consonants and vowels: _proquints_.

Today I read a paper titled “Inaccessibility-Inside Theorem for Point in Polygon”

The abstract is:
The manuscript presents a theoretical proof in conglomeration with new definitions on Inaccessibility and Inside for a point S related to a simple or self intersecting polygon P.

The proposed analytical solution depicts a novel way of solving the point in polygon problem by employing the properties of epigraphs and hypographs, explicitly.

Contrary to the ambiguous solutions given by the cross over for the simple and self intersecting polygons and the solution of a point being multiply inside a self intersecting polygon given by the winding number rule, the current solution gives unambiguous and singular result for both kinds of polygons.

Finally, the current theoretical solution proves to be mathematically correct for simple and self intersecting polygons.

Today I read a paper titled “A network model with structured nodes”

The abstract is:
We present a network model in which words over a specific alphabet, called {\it structures}, are associated to each node and undirected edges are added depending on some distance between different structures.

It is shown that this model can generate, without the use of preferential attachment or any other heuristic, networks with topological features similar to biological networks: power law degree distribution, clustering coefficient independent from the network size, etc.

Specific biological networks ({\it C.

Elegans} neural network and {\it E.

Coli} protein-protein interaction network) are replicated using this model.

Today I read a paper titled “Automatic Recommendation for Online Users Using Web Usage Mining”

The abstract is:
A real world challenging task of the web master of an organization is to match the needs of user and keep their attention in their web site.

So, only option is to capture the intuition of the user and provide them with the recommendation list.

Most specifically, an online navigation behavior grows with each passing day, thus extracting information intelligently from it is a difficult issue.

Web master should use web usage mining method to capture intuition.

A WUM is designed to operate on web server logs which contain user’s navigation.

Hence, recommendation system using WUM can be used to forecast the navigation pattern of user and recommend those to user in a form of recommendation list.

In this paper, we propose a two tier architecture for capturing users intuition in the form of recommendation list containing pages visited by user and pages visited by other user’s having similar usage profile.

The practical implementation of proposed architecture and algorithm shows that accuracy of user intuition capturing is improved.

Today I read a paper titled “PageRank Optimization by Edge Selection”

The abstract is:
The importance of a node in a directed graph can be measured by its PageRank.

The PageRank of a node is used in a number of application contexts – including ranking websites – and can be interpreted as the average portion of time spent at the node by an infinite random walk.

We consider the problem of maximizing the PageRank of a node by selecting some of the edges from a set of edges that are under our control.

By applying results from Markov decision theory, we show that an optimal solution to this problem can be found in polynomial time.

Our core solution results in a linear programming formulation, but we also provide an alternative greedy algorithm, a variant of policy iteration, which runs in polynomial time, as well.

Finally, we show that, under the slight modification for which we are given mutually exclusive pairs of edges, the problem of PageRank optimization becomes NP-hard.

Today I read a paper titled “Moveable objects and applications, based on them”

The abstract is:
The inner views of all our applications are predetermined by the designers; only some non-significant variations are allowed with the help of adaptive interface.

In several programs you can find some moveable objects, but it is an extremely rare thing.

However, the design of applications on the basis of moveable and resizable objects opens an absolutely new way of programming; such applications are much more effective in users’ work, because each user can adjust an application to his purposes.

Programs, using adaptive interface, only implement the designer’s ideas of what would be the best reaction to any of the users’ doings or commands.

Applications on moveable elements do not have such predetermined system of rules; they are fully controlled by the users.

This article describes and demonstrates the new way of applications’ design.

Today I read a paper titled “Urologic robots and future directions”

The abstract is:
PURPOSE OF REVIEW: Robot-assisted laparoscopic surgery in urology has gained immense popularity with the daVinci system, but a lot of research teams are working on new robots.

The purpose of this study is to review current urologic robots and present future development directions.

RECENT FINDINGS: Future systems are expected to advance in two directions: improvements of remote manipulation robots and developments of image-guided robots.

SUMMARY: The final goal of robots is to allow safer and more homogeneous outcomes with less variability of surgeon performance, as well as new tools to perform tasks on the basis of medical transcutaneous imaging, in a less invasive way, at lower costs.

It is expected that improvements for a remote system could be augmented in reality, with haptic feedback, size reduction, and development of new tools for natural orifice translumenal endoscopic surgery.

The paradigm of image-guided robots is close to clinical availability and the most advanced robots are presented with end-user technical assessments.

It is also notable that the potential of robots lies much further ahead than the accomplishments of the daVinci system.

The integration of imaging with robotics holds a substantial promise, because this can accomplish tasks otherwise impossible.

Image-guided robots have the potential to offer a paradigm shift.

Today I read a paper titled “Deployment of mobile routers ensuring coverage and connectivity”

The abstract is:
Maintaining connectivity among a group of autonomous agents exploring an area is very important, as it promotes cooperation between the agents and also helps message exchanges which are very critical for their mission.

Creating an underlying Ad-hoc Mobile Router Network (AMRoNet) using simple robotic routers is an approach that facilitates communication between the agents without restricting their movements.

We address the following question in our paper: How to create an AMRoNet with local information and with minimum number of routers? We propose two new localized and distributed algorithms 1) agent-assisted router deployment and 2) a self-spreading for creating AMRoNet.

The algorithms use a greedy deployment strategy for deploying routers effectively into the area maximizing coverage and a triangular deployment strategy to connect different connected component of routers from different base stations.

Empirical analysis shows that the proposed algorithms are the two best localized approaches to create AMRoNets.