The science papers I've read

Today I read a paper titled “Mathematical models of the complex surfaces in simulation and visualization systems”

The abstract is:
Modeling, simulation and visualization of three-dimension complex bodies widely use mathematical model of curves and surfaces.

The most important curves and surfaces for these purposes are curves and surfaces in Hermite and Bezier forms, splines and NURBS.

Article is devoted to survey this way to use geometrical data in various computer graphics systems and adjacent fields.

Today I read a paper titled “Extraction of cartographic objects in high resolution satellite images for object model generation”

The abstract is:
The aim of this study is to detect man-made cartographic objects in high-resolution satellite images.

New generation satellites offer a sub-metric spatial resolution, in which it is possible (and necessary) to develop methods at object level rather than at pixel level, and to exploit structural features of objects.

With this aim, a method to generate structural object models from manually segmented images has been developed.

To generate the model from non-segmented images, extraction of the objects from the sample images is required.

A hybrid method of extraction (both in terms of input sources and segmentation algorithms) is proposed: A region based segmentation is applied on a 10 meter resolution multi-spectral image.

The result is used as marker in a “marker-controlled watershed method using edges” on a 2.5 meter resolution panchromatic image.

Very promising results have been obtained even on images where the limits of the target objects are not apparent.

Today I read a paper titled “User-driven applications”

The abstract is:
User-driven applications are the programs, in which the full control is given to the users.

Designers of such programs are responsible only for developing an instrument for solving some task, but they do not enforce users to work with this instrument according with the predefined scenario.

Users’ control of the applications means that only users decide at any moment WHAT, WHEN, and HOW must appear on the screen.

Such applications can be constructed only on the basis of moveable / resizable elements.

Programs, based on such elements, have very interesting features and open absolutely new possibilities.

This article describes the design of the user-driven applications and shows the consequences of switching to such type of programs on the samples from different areas.

Today I read a paper titled “Study of Self-Organization Model of Multiple Mobile Robot”

The abstract is:
A good organization model of multiple mobile robot should be able to improve the efficiency of the system, reduce the complication of robot interactions, and detract the difficulty of computation.

From the sociology aspect of topology, structure and organization, this paper studies the multiple mobile robot organization formation and running mechanism in the dynamic, complicated and unknown environment.

It presents and describes in detail a Hierarchical- Web Recursive Organization Model (HWROM) and forming algorithm.

It defines the robot society leader; robotic team leader and individual robot as the same structure by the united framework and describes the organization model by the recursive structure.

The model uses task-oriented and top-down method to dynamically build and maintain structures and organization.

It uses market-based techniques to assign task, form teams and allocate resources in dynamic environment.

The model holds several characteristics of self-organization, dynamic, conciseness, commonness and robustness.

Today I read a paper titled “Image Retrieval Techniques based on Image Features, A State of Art approach for CBIR”

The abstract is:
The purpose of this Paper is to describe our research on different feature extraction and matching techniques in designing a Content Based Image Retrieval (CBIR) system.

Due to the enormous increase in image database sizes, as well as its vast deployment in various applications, the need for CBIR development arose.

Firstly, this paper outlines a description of the primitive feature extraction techniques like, texture, colour, and shape.

Once these features are extracted and used as the basis for a similarity check between images, the various matching techniques are discussed.

Furthermore, the results of its performance are illustrated by a detailed example.

Today I read a paper titled “Object-Oriented Program Comprehension: Effect of Expertise, Task and Phase”

The abstract is:
The goal of our study is to evaluate the effect on program comprehension of three factors that have not previously been studied in a single experiment.

These factors are programmer expertise (expert vs.

novice), programming task (documentation vs.

reuse), and the development of understanding over time (phase 1 vs.

phase 2).

This study is carried out in the context of the mental model approach to comprehension based on van Dijk and Kintsch’s model (1983).

One key aspect of this model is the distinction between two kinds of representation the reader might construct from a text: 1) the textbase, which refers to what is said in the text and how it is said, and 2) the situation model, which represents the situation referred to by the text.

We have evaluated the effect of the three factors mentioned above on the development of both the textbase (or program model) and the situation model in object-oriented program comprehension.

We found a four-way interaction of expertise, phase, task and type of model.

For the documentation group we found that experts and novices differ in the elaboration of their situation model but not their program model.

There was no interaction of expertise with phase and type of model in the documentation group.

For the reuse group, there was a three-way interaction between phase, expertise and type of model.

For the novice reuse group, the effect of the phase was to increase the construction of the situation model but not the program model.

With respect to the task, our results show that novices do not spontaneously construct a strong situation model but are able to do so if the task demands it.

Today I read a paper titled “Detecting and Tracking the Spread of Astroturf Memes in Microblog Streams”

The abstract is:
Online social media are complementing and in some cases replacing person-to-person social interaction and redefining the diffusion of information.

In particular, microblogs have become crucial grounds on which public relations, marketing, and political battles are fought.

We introduce an extensible framework that will enable the real-time analysis of meme diffusion in social media by mining, visualizing, mapping, classifying, and modeling massive streams of public microblogging events.

We describe a Web service that leverages this framework to track political memes in Twitter and help detect astroturfing, smear campaigns, and other misinformation in the context of U.S.

political elections.

We present some cases of abusive behaviors uncovered by our service.

Finally, we discuss promising preliminary results on the detection of suspicious memes via supervised learning based on features extracted from the topology of the diffusion networks, sentiment analysis, and crowdsourced annotations.

Today I read a paper titled “Is the crowd’s wisdom biased? A quantitative asessment of three online communities”

The abstract is:
This paper presents a study of user voting on three websites: Imdb, Amazon and BookCrossings.

It reports on an expert evaluation of the voting mechanisms of each website and a quantitative data analysis of users’ aggregate voting behavior.

The results suggest that voting follows different patterns across the websites, with higher barrier to vote introducing a more of one-off voters and attracting mostly experts.

The results also show that that one-off voters tend to vote on popular items, while experts mostly vote for obscure, low-rated items.

The study concludes with design suggestions to address the “wisdom of the crowd” bias.

Today I read a paper titled “On weakly optimal partitions in modular networks”

The abstract is:
Modularity was introduced as a measure of goodness for the community structure induced by a partition of the set of vertices in a graph.

Then, it also became an objective function used to find good partitions, with high success.

Nevertheless, some works have shown a scaling limit and certain instabilities when finding communities with this criterion.

Modularity has been studied proposing several formalisms, as hamiltonians in a Potts model or laplacians in spectral partitioning.

In this paper we present a new probabilistic formalism to analyze modularity, and from it we derive an algorithm based on weakly optimal partitions.

This algorithm obtains good quality partitions and also scales to large graphs.

Today I read a paper titled “The Good, the Bad, and the Ugly: three different approaches to break their watermarking system”

The abstract is:
The Good is Blondie, a wandering gunman with a strong personal sense of honor.

The Bad is Angel Eyes, a sadistic hitman who always hits his mark.

The Ugly is Tuco, a Mexican bandit who’s always only looking out for himself.

Against the backdrop of the BOWS contest, they search for a watermark in gold buried in three images.

Each knows only a portion of the gold’s exact location, so for the moment they’re dependent on each other.

However, none are particularly inclined to share…

Today I read a paper titled “High Speed and Area Efficient 2D DWT Processor based Image Compression” Signal & Image Processing”

The abstract is:
This paper presents a high speed and area efficient DWT processor based design for Image Compression applications.

In this proposed design, pipelined partially serial architecture has been used to enhance the speed along with optimal utilization and resources available on target FPGA.

The proposed model has been designed and simulated using Simulink and System Generator blocks, synthesized with Xilinx Synthesis tool (XST) and implemented on Spartan 2 and 3 based XC2S100-5tq144 and XC3S500E-4fg320 target device.

The results show that proposed design can operate at maximum frequency 231 MHz in case of Spartan 3 by consuming power of 117mW at 28 degree/c junction temperature.

The result comparison has shown an improvement of 15% in speed.

Today I read a paper titled “Multimedia Applications of Multiprocessor Systems-on-Chips”

The abstract is:
This paper surveys the characteristics of multimedia systems.

Multimedia applications today are dominated by compression and decompression, but multimedia devices must also implement many other functions such as security and file management.

We introduce some basic concepts of multimedia algorithms and the larger set of functions that multimedia systems-on-chips must implement.

Today I read a paper titled “Warping Peirce Quincuncial Panoramas”

The abstract is:
The Peirce quincuncial projection is a mapping of the surface of a sphere to the interior of a square.

It is a conformal map except for four points on the equator.

These points of non-conformality cause significant artifacts in photographic applications.

In this paper, we propose an algorithm and user-interface to mitigate these artifacts.

Moreover, in order to facilitate an interactive user-interface, we present a fast algorithm for calculating the Peirce quincuncial projection of spherical imagery.

We then promote the Peirce quincuncial projection as a viable alternative to the more popular stereographic projection in some scenarios.

Today I read a paper titled “Virtual Reality”

The abstract is:
This paper is focused on the presentation of Virtual Reality principles together with the main implementation methods and techniques.

An overview of the main development directions is included.

Today I read a paper titled “Semantic Modeling and Retrieval of Dance Video Annotations”

The abstract is:
Dance video is one of the important types of narrative videos with semantic rich content.

This paper proposes a new meta model, Dance Video Content Model (DVCM) to represent the expressive semantics of the dance videos at multiple granularity levels.

The DVCM is designed based on the concepts such as video, shot, segment, event and object, which are the components of MPEG-7 MDS.

This paper introduces a new relationship type called Temporal Semantic Relationship to infer the semantic relationships between the dance video objects.

Inverted file based index is created to reduce the search time of the dance queries.

The effectiveness of containment queries using precision and recall is depicted.

Keywords: Dance Video Annotations, Effectiveness Metrics, Metamodeling, Temporal Semantic Relationships.

Today I read a paper titled “Toward a general theory of quantum games”

The abstract is:
We study properties of quantum strategies, which are complete specifications of a given party’s actions in any multiple-round interaction involving the exchange of quantum information with one or more other parties.

In particular, we focus on a representation of quantum strategies that generalizes the Choi-Jamio{\l}kowski representation of quantum operations.

This new representation associates with each strategy a positive semidefinite operator acting only on the tensor product of its input and output spaces.

Various facts about such representations are established, and two applications are discussed: the first is a new and conceptually simple proof of Kitaev’s lower bound for strong coin-flipping, and the second is a proof of the exact characterization QRG = EXP of the class of problems having quantum refereed games.

Today I read a paper titled “Bottom-Up Earley Deduction”

The abstract is:
We propose a bottom-up variant of Earley deduction.

Bottom-up deduction is preferable to top-down deduction because it allows incremental processing (even for head-driven grammars), it is data-driven, no subsumption check is needed, and preference values attached to lexical items can be used to guide best-first search.

We discuss the scanning step for bottom-up Earley deduction and indexing schemes that help avoid useless deduction steps..

Today I read a paper titled “Pattern Recognition System Design with Linear Encoding for Discrete Patterns”

The abstract is:
In this paper, designs and analyses of compressive recognition systems are discussed, and also a method of establishing a dual connection between designs of good communication codes and designs of recognition systems is presented.

Pattern recognition systems based on compressed patterns and compressed sensor measurements can be designed using low-density matrices.

We examine truncation encoding where a subset of the patterns and measurements are stored perfectly while the rest is discarded.

We also examine the use of LDPC parity check matrices for compressing measurements and patterns.

We show how more general ensembles of good linear codes can be used as the basis for pattern recognition system design, yielding system design strategies for more general noise models.

Today I read a paper titled “Optimizing Web Sites for Customer Retention”

The abstract is:
With customer relationship management (CRM) companies move away from a mainly product-centered view to a customer-centered view.

Resulting from this change, the effective management of how to keep contact with customers throughout different channels is one of the key success factors in today’s business world.

Company Web sites have evolved in many industries into an extremely important channel through which customers can be attracted and retained.

To analyze and optimize this channel, accurate models of how customers browse through the Web site and what information within the site they repeatedly view are crucial.

Typically, data mining techniques are used for this purpose.

However, there already exist numerous models developed in marketing research for traditional channels which could also prove valuable to understanding this new channel.

In this paper we propose the application of an extension of the Logarithmic Series Distribution (LSD) model repeat-usage of Web-based information and thus to analyze and optimize a Web Site’s capability to support one goal of CRM, to retain customers.

As an example, we use the university’s blended learning web portal with over a thousand learning resources to demonstrate how the model can be used to evaluate and improve the Web site’s effectiveness.

Today I read a paper titled “An analysis of a random algorithm for estimating all the matchings”

The abstract is:
Counting the number of all the matchings on a bipartite graph has been transformed into calculating the permanent of a matrix obtained from the extended bipartite graph by Yan Huo, and Rasmussen presents a simple approach (RM) to approximate the permanent, which just yields a critical ratio O($n\omega(n)$) for almost all the 0-1 matrices, provided it’s a simple promising practical way to compute this #P-complete problem.

In this paper, the performance of this method will be shown when it’s applied to compute all the matchings based on that transformation.

The critical ratio will be proved to be very large with a certain probability, owning an increasing factor larger than any polynomial of $n$ even in the sense for almost all the 0-1 matrices.

Hence, RM fails to work well when counting all the matchings via computing the permanent of the matrix.

In other words, we must carefully utilize the known methods of estimating the permanent to count all the matchings through that transformation.

Today I read a paper titled “The Labor Economics of Paid Crowdsourcing”

The abstract is:
Crowdsourcing is a form of “peer production” in which work traditionally performed by an employee is outsourced to an “undefined, generally large group of people in the form of an open call.” We present a model of workers supplying labor to paid crowdsourcing projects.

We also introduce a novel method for estimating a worker’s reservation wage–the smallest wage a worker is willing to accept for a task and the key parameter in our labor supply model.

It shows that the reservation wages of a sample of workers from Amazon’s Mechanical Turk (AMT) are approximately log normally distributed, with a median wage of $1.38/hour.

At the median wage, the point elasticity of extensive labor supply is 0.43.

We discuss how to use our calibrated model to make predictions in applied work.

Two experimental tests of the model show that many workers respond rationally to offered incentives.

However, a non-trivial fraction of subjects appear to set earnings targets.

These “target earners” consider not just the offered wage–which is what the rational model predicts–but also their proximity to earnings goals.

Interestingly, a number of workers clearly prefer earning total amounts evenly divisible by 5, presumably because these amounts make good targets.

Today I read a paper titled “An Algebraic Approach for the MIMO Control of Small Scale Helicopter”

The abstract is:
The control of small-scale helicopter is a MIMO problem.

To use of classical control approach to formally solve a MIMO problem, one needs to come up with multidimensional Root Locus diagram to tune the control parameters.

The problem with the required dimension of the RL diagram for MIMO design has forced the design procedure of classical approach to be conducted in cascaded multi-loop SISO system starting from the innermost loop outward.

To implement this control approach for a helicopter, a pitch and roll attitude control system is often subordinated to a, respectively, longitudinal and lateral velocity control system in a nested architecture.

The requirement for this technique to work is that the inner attitude control loop must have a higher bandwidth than the outer velocity control loop which is not the case for high performance mini helicopter.

To address the above problems, an algebraic design approach is proposed in this work.

The designed control using s-CDM approach is demonstrated for hovering control of small-scale helicopter simultaneously subjected to plant parameter uncertainties and wind disturbances.

Today I read a paper titled “Discernment of Hubs and Clusters in Socioeconomic Networks”

The abstract is:
Interest in the analysis of networks has grown rapidly in the new millennium.

Consequently, we promote renewed attention to a certain methodological approach introduced in 1974.

Over the succeeding decade, this two-stage–double-standardization and hierarchical clustering (single-linkage-like)–procedure was applied to a wide variety of weighted, directed networks of a socioeconomic nature, frequently revealing the presence of “hubs”.

These were, typically–in the numerous instances studied of migration flows between geographic subdivisions within nations–“cosmopolitan/non-provincial” areas, a prototypical example being the French capital, Paris.

Such locations emit and absorb people broadly across their respective nations.

Additionally, the two-stage procedure–which “might very well be the most successful application of cluster analysis” (R.

C.

Dubes, 1985)–detected many (physically or socially) isolated, functional groups (regions) of areas, such as the southern islands, Shikoku and Kyushu, of Japan, the Italian islands of Sardinia and Sicily, and the New England region of the United States.

Further, we discuss a (complementary) approach developed in 1976, in which the max-flow/min-cut theorem was applied to raw/non-standardized (interindustry, as well as migration) flows.

Today I read a paper titled “Fractal Basins and Boundaries in 2D Maps inspired in Discrete Population Models”

The abstract is:
Two-dimensional maps can model interactions between populations.

Despite their simplicity, these dynamical systems can show some complex situations, as multistability or fractal boundaries between basins that lead to remarkable pictures.

Some of them are shown and explained here for three different 2D discrete models.

Today I read a paper titled “Human dynamics revealed through Web analytics”

The abstract is:
When the World Wide Web was first conceived as a way to facilitate the sharing of scientific information at the CERN (European Center for Nuclear Research) few could have imagined the role it would come to play in the following decades.

Since then, the increasing ubiquity of Internet access and the frequency with which people interact with it raise the possibility of using the Web to better observe, understand, and monitor several aspects of human social behavior.

Web sites with large numbers of frequently returning users are ideal for this task.

If these sites belong to companies or universities, their usage patterns can furnish information about the working habits of entire populations.

In this work, we analyze the properly anonymized logs detailing the access history to Emory University’s Web site.

Emory is a medium size university located in Atlanta, Georgia.

We find interesting structure in the activity patterns of the domain and study in a systematic way the main forces behind the dynamics of the traffic.

In particular, we show that both linear preferential linking and priority based queuing are essential ingredients to understand the way users navigate the Web.

Today I read a paper titled “Sustaining the Internet with Hyperbolic Mapping”

The abstract is:
The Internet infrastructure is severely stressed.

Rapidly growing overheads associated with the primary function of the Internet—routing information packets between any two computers in the world—cause concerns among Internet experts that the existing Internet routing architecture may not sustain even another decade.

Here we present a method to map the Internet to a hyperbolic space.

Guided with the constructed map, which we release with this paper, Internet routing exhibits scaling properties close to theoretically best possible, thus resolving serious scaling limitations that the Internet faces today.

Besides this immediate practical viability, our network mapping method can provide a different perspective on the community structure in complex networks.

Today I read a paper titled “Optimal Point-to-Point Trajectory Tracking of Redundant Manipulators using Generalized Pattern Search”

The abstract is:
Optimal point-to-point trajectory planning for planar redundant manipulator is considered in this study.

The main objective is to minimize the sum of the position error of the end-effector at each intermediate point along the trajectory so that the end-effector can track the prescribed trajectory accurately.

An algorithm combining Genetic Algorithm and Pattern Search as a Generalized Pattern Search GPS is introduced to design the optimal trajectory.

To verify the proposed algorithm, simulations for a 3-D-O-F planar manipulator with different end-effector trajectories have been carried out.

A comparison between the Genetic Algorithm and the Generalized Pattern Search shows that The GPS gives excellent tracking performance.

Today I read a paper titled “Ontology-Based Annotation of Multimedia Language Data for the Semantic Web”

The abstract is:
There is an increasing interest and effort in preserving and documenting endangered languages.

Language data are valuable only when they are well-cataloged, indexed and searchable.

Many language data, particularly those of lesser-spoken languages, are collected as audio and video recordings.

While multimedia data provide more channels and dimensions to describe a language’s function, and gives a better presentation of the cultural system associated with the language of that community, they are not text-based or structured (in binary format), and their semantics is implicit in their content.

The content is thus easy for a human being to understand, but difficult for computers to interpret.

Hence, there is a great need for a powerful and user-friendly system to annotate multimedia data with text-based, well-structured and searchable metadata.

This chapter describes an ontology-based multimedia annotation tool, OntoELAN, that enables annotation of language multimedia data with a linguistic ontology.

Today I read a paper titled “Gameplay experience in a gaze interaction game”

The abstract is:
Assessing gameplay experience for gaze interaction games is a challenging task.

For this study, a gaze interaction Half-Life 2 game modification was created that allowed eye tracking control.

The mod was deployed during an experiment at Dreamhack 2007, where participants had to play with gaze navigation and afterwards rate their gameplay experience.

The results show low tension and negative affects scores on the gameplay experience questionnaire as well as high positive challenge, immersion and flow ratings.

The correlation between spatial presence and immersion for gaze interaction was high and yields further investigation.

It is concluded that gameplay experience can be correctly assessed with the methodology presented in this paper.

Today I read a paper titled “Expansion and Search in Networks”

The abstract is:
Borrowing from concepts in expander graphs, we study the expansion properties of real-world, complex networks (e.g.

social networks, unstructured peer-to-peer or P2P networks) and the extent to which these properties can be exploited to understand and address the problem of decentralized search.

We first produce samples that concisely capture the overall expansion properties of an entire network, which we collectively refer to as the expansion signature.

Using these signatures, we find a correspondence between the magnitude of maximum expansion and the extent to which a network can be efficiently searched.

We further find evidence that standard graph-theoretic measures, such as average path length, fail to fully explain the level of “searchability” or ease of information diffusion and dissemination in a network.

Finally, we demonstrate that this high expansion can be leveraged to facilitate decentralized search in networks and show that an expansion-based search strategy outperforms typical search methods.

Today I read a paper titled “Cryptanalysis of an image encryption scheme based on a new total shuffling algorithm”

The abstract is:
Chaotic systems have been broadly exploited through the last two decades to build encryption methods.

Recently, two new image encryption schemes have been proposed, where the encryption process involves a permutation operation and an XOR-like transformation of the shuffled pixels, which are controlled by three chaotic systems.

This paper discusses some defects of the schemes and how to break them with a chosen-plaintext attack.

Today I read a paper titled “On the Correlation of Geographic and Network Proximity at Internet Edges and its Implications for Mobile Unicast and Multicast Routing”

The abstract is:
Significant effort has been invested recently to accelerate handover operations in a next generation mobile Internet.

Corresponding works for developing efficient mobile multicast management are emergent.

Both problems simultaneously expose routing complexity between subsequent points of attachment as a characteristic parameter for handover performance in access networks.

As continuous mobility handovers necessarily occur between access routers located in geographic vicinity, this paper investigates on the hypothesis that geographically adjacent edge networks attain a reduced network distances as compared to arbitrary Internet nodes.

We therefore evaluate and analyze edge distance distributions in various regions for clustered IP ranges on their geographic location such as a city.

We use traceroute to collect packet forwarding path and round-trip-time of each intermediate node to scan-wise derive an upper bound of the node distances.

Results of different scanning origins are compared to obtain the best estimation of network distance of each pair.

Our results are compared with corresponding analysis of CAIDA Skitter data, overall leading to fairly stable, reproducible edge distance distributions.

As a first conclusion on expected impact on handover performance measures, our results indicate a general optimum for handover anticipation time in 802.11 networks of 25 ms.

Today I read a paper titled “Complex networks derived from cellular automata”

The abstract is:
We propose a method for deriving networks from one-dimensional binary cellular automata.

The derived networks are usually directed and have structural properties corresponding to the dynamical behaviors of their cellular automata.

Network parameters, particularly the efficiency and the degree distribution, show that the dependence of efficiency on the grid size is characteristic and can be used to classify cellular automata and that derived networks exhibit various degree distributions.

In particular, a class IV rule of Wolfram’s classification produces a network having a scale-free distribution.

Today I read a paper titled “Autonomous detection and anticipation of jam fronts from messages propagated by inter-vehicle communication”

The abstract is:
In this paper, a minimalist, completely distributed freeway traffic information system is introduced.

It involves an autonomous, vehicle-based jam front detection, the information transmission via inter-vehicle communication, and the forecast of the spatial position of jam fronts by reconstructing the spatiotemporal traffic situation based on the transmitted information.

The whole system is simulated with an integrated traffic simulator, that is based on a realistic microscopic traffic model for longitudinal movements and lane changes.

The function of its communication module has been explicitly validated by comparing the simulation results with analytical calculations.

By means of simulations, we show that the algorithms for a congestion-front recognition, message transmission, and processing predict reliably the existence and position of jam fronts for vehicle equipment rates as low as 3%.

A reliable mode of operation already for small market penetrations is crucial for the successful introduction of inter-vehicle communication.

The short-term prediction of jam fronts is not only useful for the driver, but is essential for enhancing road safety and road capacity by intelligent adaptive cruise control systems.

Today I read a paper titled “Polyomino-Based Digital Halftoning”

The abstract is:
In this work, we present a new method for generating a threshold structure.

This kind of structure can be advantageously used in various halftoning algorithms such as clustered-dot or dispersed-dot dithering, error diffusion with threshold modulation, etc.

The proposed method is based on rectifiable polyominoes — a non-periodic hierarchical structure, which tiles the Euclidean plane with no gaps.

Each polyomino contains a fixed number of discrete threshold values.

Thanks to its inherent non-periodic nature combined with off-line optimization of threshold values, our polyomino-based threshold structure shows blue-noise spectral properties.

The halftone images produced with this threshold structure have high visual quality.

Although the proposed method is general, and can be applied on any polyomino tiling, we consider one particular case: tiling with G-hexominoes.

We compare our polyomino-based threshold structure with the best known state-of-the-art methods for generation threshold matrices, and conclude considerable improvement achieved with our method.

Today I read a paper titled “Functional Brain Imaging with Multi-Objective Multi-Modal Evolutionary Optimization”

The abstract is:
Functional brain imaging is a source of spatio-temporal data mining problems.

A new framework hybridizing multi-objective and multi-modal optimization is proposed to formalize these data mining problems, and addressed through Evolutionary Computation (EC).

The merits of EC for spatio-temporal data mining are demonstrated as the approach facilitates the modelling of the experts’ requirements, and flexibly accommodates their changing goals.

Today I read a paper titled “The Complexity of Simple Stochastic Games”

The abstract is:
In this paper we survey the computational time complexity of assorted simple stochastic game problems, and we give an overview of the best known algorithms associated with each problem.

Today I read a paper titled “A parent-centered radial layout algorithm for interactive graph visualization and animation”

The abstract is:
We have developed (1) a graph visualization system that allows users to explore graphs by viewing them as a succession of spanning trees selected interactively, (2) a radial graph layout algorithm, and (3) an animation algorithm that generates meaningful visualizations and smooth transitions between graphs while minimizing edge crossings during transitions and in static layouts.

Our system is similar to the radial layout system of Yee et al.

(2001), but differs primarily in that each node is positioned on a coordinate system centered on its own parent rather than on a single coordinate system for all nodes.

Our system is thus easy to define recursively and lends itself to parallelization.

It also guarantees that layouts have many nice properties, such as: it guarantees certain edges never cross during an animation.

We compared the layouts and transitions produced by our algorithms to those produced by Yee et al.

Results from several experiments indicate that our system produces fewer edge crossings during transitions between graph drawings, and that the transitions more often involve changes in local scaling rather than structure.

These findings suggest the system has promise as an interactive graph exploration tool in a variety of settings.

Today I read a paper titled “Node discovery in a networked organization”

The abstract is:
In this paper, I present a method to solve a node discovery problem in a networked organization.

Covert nodes refer to the nodes which are not observable directly.

They affect social interactions, but do not appear in the surveillance logs which record the participants of the social interactions.

Discovering the covert nodes is defined as identifying the suspicious logs where the covert nodes would appear if the covert nodes became overt.

A mathematical model is developed for the maximal likelihood estimation of the network behind the social interactions and for the identification of the suspicious logs.

Precision, recall, and F measure characteristics are demonstrated with the dataset generated from a real organization and the computationally synthesized datasets.

The performance is close to the theoretical limit for any covert nodes in the networks of any topologies and sizes if the ratio of the number of observation to the number of possible communication patterns is large.

Today I read a paper titled “An Iterative Fingerprint Enhancement Algorithm Based on Accurate Determination of Orientation Flow”

The abstract is:
We describe an algorithm to enhance and binarize a fingerprint image.

The algorithm is based on accurate determination of orientation flow of the ridges of the fingerprint image by computing variance of the neighborhood pixels around a pixel in different directions.

We show that an iterative algorithm which captures the mutual interdependence of orientation flow computation, enhancement and binarization gives very good results on poor quality images.

Today I read a paper titled “Review of Robust Video Watermarking Algorithms”

The abstract is:
There has been a remarkable increase in the data exchange over web and the widespread use of digital media.

As a result, multimedia data transfers also had a boost up.

The mounting interest with reference to digital watermarking throughout the last decade is certainly due to the increase in the need of copyright protection of digital content.

This is also enhanced due to commercial prospective.

Applications of video watermarking in copy control, broadcast monitoring, fingerprinting, video authentication, copyright protection etc is immensely rising.

The main aspects of information hiding are capacity, security and robustness.

Capacity deals with the amount of information that can be hidden.

The skill of anyone detecting the information is security and robustness refers to the resistance to modification of the cover content before concealed information is destroyed.

Video watermarking algorithms normally prefers robustness.

In a robust algorithm it is not possible to eliminate the watermark without rigorous degradation of the cover content.

In this paper, we introduce the notion of Video Watermarking and the features required to design a robust watermarked video for a valuable application.

We review several algorithms, and introduce frequently used key techniques.

The aim of this paper is to focus on the various domains of video watermarking techniques.

The majority of the reviewed methods based on video watermarking emphasize on the notion of robustness of the algorithm.

Today I read a paper titled “The Many Faces of Rationalizability”

The abstract is:
The rationalizability concept was introduced in \cite{Ber84} and \cite{Pea84} to assess what can be inferred by rational players in a non-cooperative game in the presence of common knowledge.

However, this notion can be defined in a number of ways that differ in seemingly unimportant minor details.

We shed light on these differences, explain their impact, and clarify for which games these definitions coincide.

Then we apply the same analysis to explain the differences and similarities between various ways the iterated elimination of strictly dominated strategies was defined in the literature.

This allows us to clarify the results of \cite{DS02} and \cite{CLL05} and improve upon them.

We also consider the extension of these results to strict dominance by a mixed strategy.

Our approach is based on a general study of the operators on complete lattices.

We allow transfinite iterations of the considered operators and clarify the need for them.

The advantage of such a general approach is that a number of results, including order independence for some of the notions of rationalizability and strict dominance, come for free.

Today I read a paper titled “How to realize “a sense of humour” in computers ?”

The abstract is:
Computer model of a “sense of humour” suggested previously [arXiv:0711.2058, 0711.2061, 0711.2270] is raised to the level of a realistic algorithm.

Today I read a paper titled “A Standalone Markerless 3D Tracker for Handheld Augmented Reality”

The abstract is:
This paper presents an implementation of a markerless tracking technique targeted to the Windows Mobile Pocket PC platform.

The primary aim of this work is to allow the development of standalone augmented reality applications for handheld devices based on natural feature tracking.

In order to achieve this goal, a subset of two computer vision libraries was ported to the Pocket PC platform.

They were also adapted to use fixed point math, with the purpose of improving the overall performance of the routines.

The port of these libraries opens up the possibility of having other computer vision tasks being executed on mobile platforms.

A model based tracking approach that relies on edge information was adopted.

Since it does not require a high processing power, it is suitable for constrained devices such as handhelds.

The OpenGL ES graphics library was used to perform computer vision tasks, taking advantage of existing graphics hardware acceleration.

An augmented reality application was created using the implemented technique and evaluations were done regarding tracking performance and accuracy .

Today I read a paper titled “Robotics Vision-based Heuristic Reasoning for Underwater Target Tracking and Navigation”

The abstract is:
This paper presents a robotics vision-based heuristic reasoning system for underwater target tracking and navigation.

This system is introduced to improve the level of automation of underwater Remote Operated Vehicles (ROVs) operations.

A prototype which combines computer vision with an underwater robotics system is successfully designed and developed to perform target tracking and intelligent navigation.

…

Today I read a paper titled “Improving Local Search for Fuzzy Scheduling Problems”

The abstract is:
The integration of fuzzy set theory and fuzzy logic into scheduling is a rather new aspect with growing importance for manufacturing applications, resulting in various unsolved aspects.

In the current paper, we investigate an improved local search technique for fuzzy scheduling problems with fitness plateaus, using a multi criteria formulation of the problem.

We especially address the problem of changing job priorities over time as studied at the Sherwood Press Ltd, a Nottingham based printing company, who is a collaborator on the project.

Today I read a paper titled “An Independent Evaluation of Subspace Face Recognition Algorithms”

The abstract is:
This paper explores a comparative study of both the linear and kernel implementations of three of the most popular Appearance-based Face Recognition projection classes, these being the methodologies of Principal Component Analysis, Linear Discriminant Analysis and Independent Component Analysis.

The experimental procedure provides a platform of equal working conditions and examines the ten algorithms in the categories of expression, illumination, occlusion and temporal delay.

The results are then evaluated based on a sequential combination of assessment tools that facilitate both intuitive and statistical decisiveness among the intra and interclass comparisons.

The best categorical algorithms are then incorporated into a hybrid methodology, where the advantageous effects of fusion strategies are considered.

Today I read a paper titled “Double Sided Watermark Embedding and Detection with Perceptual Analysis”

The abstract is:
In our previous work, we introduced a double-sided technique that utilizes but not reject the host interference.

Due to its nice property of utilizing but not rejecting the host interference, it has a big advantage over the host interference schemes in that the perceptual analysis can be easily implemented for our scheme to achieve the locally bounded maximum embedding strength.

Thus, in this work, we detail how to implement the perceptual analysis in our double-sided schemes since the perceptual analysis is very important for improving the fidelity of watermarked contents.

Through the extensive performance comparisons, we can further validate the performance advantage of our double-sided schemes.

Today I read a paper titled “Establishing A Minimum Generic Skill Set For Risk Management Teaching In A Spreadsheet Training Course”

The abstract is:
Past research shows that spreadsheet models are prone to such a high frequency of errors and data security implications that the risk management of spreadsheet development and spreadsheet use is of great importance to both industry and academia.

The underlying rationale for this paper is that spreadsheet training courses should specifically address risk management in the development process both from a generic and a domain-specific viewpoint.

This research specifically focuses on one of these namely those generic issues of risk management that should be present in a training course that attempts to meet good-practice within industry.

A pilot questionnaire was constructed showing a possible minimum set of risk management issues and sent to academics and industry practitioners for feedback.

The findings from this pilot survey will be used to refine the questionnaire for sending to a larger body of possible respondents.

It is expected these findings will form the basis of a risk management teaching approach to be trialled in a number of selected ongoing spreadsheet training courses.

Today I read a paper titled “A Walk in Facebook: Uniform Sampling of Users in Online Social Networks”

The abstract is:
Our goal in this paper is to develop a practical framework for obtaining a uniform sample of users in an online social network (OSN) by crawling its social graph.

Such a sample allows to estimate any user property and some topological properties as well.

To this end, first, we consider and compare several candidate crawling techniques.

Two approaches that can produce approximately uniform samples are the Metropolis-Hasting random walk (MHRW) and a re-weighted random walk (RWRW).

Both have pros and cons, which we demonstrate through a comparison to each other as well as to the “ground truth.” In contrast, using Breadth-First-Search (BFS) or an unadjusted Random Walk (RW) leads to substantially biased results.

Second, and in addition to offline performance assessment, we introduce online formal convergence diagnostics to assess sample quality during the data collection process.

We show how these diagnostics can be used to effectively determine when a random walk sample is of adequate size and quality.

Third, as a case study, we apply the above methods to Facebook and we collect the first, to the best of our knowledge, representative sample of Facebook users.

We make it publicly available and employ it to characterize several key properties of Facebook.