OpenRaiser/Intern-Atlas huggingface dataset:
Hybrid Systems and Control With Fractional Dynamics (I): Modeling and Analysis
Venue: arXiv cs.SY 2014
Year: 2014

No mixed research of hybrid and fractional-order systems into a cohesive and multifaceted whole can be found in the literature. This paper focuses on such a synergistic approach of the theories of both branches, which is believed to give additional flexibility and help to the system designer. It is part I of two companion papers and introduces the fundamentals of fractional-order hybrid systems, in particular, modeling and stability analysis of two kinds of such systems, i.e., fractional-order switching and reset control systems. Some examples are given to illustrate the applicability and effectiveness of the developed theory. Part II will focus on fractional-order hybrid control.
A New Routing Protocol for All Optical Network
Venue: arXiv cs.NI 2014
Year: 2014

In this research paper, an efficient routing protocol for all optical network (AOL) is proposed. The technique uses wavelength division multiplexing (WDM). The proposed one is different from the conventional AOL protocol in transmission of data and control over optical fiber. A set of wavelengths is reserved to transfer control information, which is defined as control wavelengths. Control wavelengths are routed with packet routing scheme and the others are routed with wavelength routing scheme. In connection oriented network only the control packets are sent with the control wavelengths, data or messages are sent with other wavelengths. On the other hand, in datagram network, all the packets are sent with the control wavelengths. The allocation of wavelengths may be fully dynamic.
New Method for Optimization of License Plate Recognition system with Use of Edge Detection and Connected Component
Venue: arXiv cs.CV 2014
Year: 2014

License Plate recognition plays an important role on the traffic monitoring and parking management systems. In this paper, a fast and real time method has been proposed which has an appropriate application to find tilt and poor quality plates. In the proposed method, at the beginning, the image is converted into binary mode using adaptive threshold. Then, by using some edge detection and morphology operations, plate number location has been specified. Finally, if the plat has tilt, its tilt is removed away. This method has been tested on another paper data set that has different images of the background, considering distance, and angel of view so that the correct extraction rate of plate reached at 98.66%.
Parameterized Synthesis Case Study: AMBA AHB
Venue: arXiv cs.LO 2014
Year: 2014

We revisit the AMBA AHB case study that has been used as a benchmark for several reactive synthesis tools. Synthesizing AMBA AHB implementations that can serve a large number of masters is still a difficult problem. We demonstrate how to use parameterized synthesis in token rings to obtain an implementation for a component that serves a single master, and can be arranged in a ring of arbitrarily many components. We describe new tricks - property decompositional synthesis, and direct encoding of simple GR(1) - that together with previously described optimizations allowed us to synthesize a component model with 14 states in about 1 hour.
Enhancing the Accuracy of Biometric Feature Extraction Fusion Using Gabor Filter and Mahalanobis Distance Algorithm
Venue: arXiv cs.CV 2014
Year: 2014

Biometric recognition systems have advanced significantly in the last decade and their use in specific applications will increase in the near future. The ability to conduct meaningful comparisons and assessments will be crucial to successful deployment and increasing biometric adoption. The best modality used as unimodal biometric systems are unable to fully address the problem of higher recognition rate. Multimodal biometric systems are able to mitigate some of the limitations encountered in unimodal biometric systems, such as non-universality, distinctiveness, non-acceptability, noisy sensor data, spoof attacks, and performance. More reliable recognition accuracy and performance are achievable as different modalities were being combined together and different algorithms or techniques were being used. The work presented in this paper focuses on a bimodal biometric system using face and fingerprint. An image enhancement technique (histogram equalization) is used to enhance the face and fingerprint images. Salient features of the face and fingerprint were extracted using the Gabor filter technique. A dimensionality reduction technique was carried out on both images extracted features using a principal component analysis technique. A feature level fusion algorithm (Mahalanobis distance technique) is used to combine each unimodal feature together. The performance of the proposed approach is validated and is effective.
Faster Fully-Dynamic Minimum Spanning Forest
Venue: arXiv cs.DS 2014
Year: 2014

We give a new data structure for the fully-dynamic minimum spanning forest problem in simple graphs. Edge updates are supported in $O(\log^4n/\log\log n)$ amortized time per operation, improving the $O(\log^4n)$ amortized bound of Holm et al. (STOC'98, JACM'01). We assume the Word-RAM model with standard instructions.
A Theory of Cheap Control in Embodied Systems
Venue: arXiv cs.SY 2014
Year: 2014

We present a framework for designing cheap control architectures for embodied agents. Our derivation is guided by the classical problem of universal approximation, whereby we explore the possibility of exploiting the agent's embodiment for a new and more efficient universal approximation of behaviors generated by sensorimotor control. This embodied universal approximation is compared with the classical non-embodied universal approximation. To exemplify our approach, we present a detailed quantitative case study for policy models defined in terms of conditional restricted Boltzmann machines. In contrast to non-embodied universal approximation, which requires an exponential number of parameters, in the embodied setting we are able to generate all possible behaviors with a drastically smaller model, thus obtaining cheap universal approximation. We test and corroborate the theory experimentally with a six-legged walking machine. The experiments show that the sufficient controller complexity predicted by our theory is tight, which means that the theory has direct practical implications. Keywords: cheap design, embodiment, sensorimotor loop, universal approximation, conditional restricted Boltzmann machine
Faster Separators for Shallow Minor-Free Graphs via Dynamic Approximate Distance Oracles
Venue: arXiv cs.DS 2014
Year: 2014

Plotkin, Rao, and Smith (SODA'97) showed that any graph with $m$ edges and $n$ vertices that excludes $K_h$ as a depth $O(\ell\log n)$-minor has a separator of size $O(n/\ell + \ell h^2\log n)$ and that such a separator can be found in $O(mn/\ell)$ time. A time bound of $O(m + n^{2+ε}/\ell)$ for any constant $ε> 0$ was later given (W., FOCS'11) which is an improvement for non-sparse graphs. We give three new algorithms. The first has the same separator size and running time $O(\mbox{poly}(h)\ell m^{1+ε})$. This is a significant improvement for small $h$ and $\ell$. If $\ell = Ω(n^{ε'})$ for an arbitrarily small chosen constant $ε' > 0$, we get a time bound of $O(\mbox{poly}(h)\ell n^{1+ε})$. The second algorithm achieves the same separator size (with a slightly larger polynomial dependency on $h$) and running time $O(\mbox{poly}(h)(\sqrt\ell n^{1+ε} + n^{2+ε}/\ell^{3/2}))$ when $\ell = Ω(n^{ε'})$. Our third algorithm has running time $O(\mbox{poly}(h)\sqrt\ell n^{1+ε})$ when $\ell = Ω(n^{ε'})$. It finds a separator of size $O(n/\ell) + \tilde O(\mbox{poly}(h)\ell\sqrt n)$ which is no worse than previous bounds when $h$ is fixed and $\ell = \tilde O(n^{1/4})$. A main tool in obtaining our results is a novel application of a decremental approximate distance oracle of Roditty and Zwick.
Hardware extensions to make lazy subscription safe
Venue: arXiv cs.PL 2014
Year: 2014

Transactional Lock Elision (TLE) uses Hardware Transactional Memory (HTM) to execute unmodified critical sections concurrently, even if they are protected by the same lock. To ensure correctness, the transactions used to execute these critical sections "subscribe" to the lock by reading it and checking that it is available. A recent paper proposed using the tempting "lazy subscription" optimization for a similar technique in a different context, namely transactional systems that use a single global lock (SGL) to protect all transactional data. We identify several pitfalls that show that lazy subscription \emph{is not safe} for TLE because unmodified critical sections executing before subscribing to the lock may behave incorrectly in a number of subtle ways. We also show that recently proposed compiler support for modifying transaction code to ensure subscription occurs before any incorrect behavior could manifest is not sufficient to avoid all of the pitfalls we identify. We further argue that extending such compiler support to avoid all pitfalls would add substantial complexity and would usually limit the extent to which subscription can be deferred, undermining the effectiveness of the optimization. Hardware extensions suggested in the recent proposal also do not address all of the pitfalls we identify. In this extended version of our WTTM 2014 paper, we describe hardware extensions that make lazy subscription safe, both for SGL-based transactional systems and for TLE, without the need for special compiler support. We also explain how nontransactional loads can be exploited, if available, to further enhance the effectiveness of lazy subscription.
Fast Spammer Detection Using Structural Rank
Venue: arXiv cs.IR 2014
Year: 2014

Comments for a product or a news article are rapidly growing and became a medium of measuring quality products or services. Consequently, spammers have been emerged in this area to bias them toward their favor. In this paper, we propose an efficient spammer detection method using structural rank of author specific term-document matrices. The use of structural rank was found effective and far faster than similar methods.
Pushbroom Stereo for High-Speed Navigation in Cluttered Environments
Venue: arXiv cs.RO 2014
Year: 2014

We present a novel stereo vision algorithm that is capable of obstacle detection on a mobile-CPU processor at 120 frames per second. Our system performs a subset of standard block-matching stereo processing, searching only for obstacles at a single depth. By using an onboard IMU and state-estimator, we can recover the position of obstacles at all other depths, building and updating a full depth-map at framerate. Here, we describe both the algorithm and our implementation on a high-speed, small UAV, flying at over 20 MPH (9 m/s) close to obstacles. The system requires no external sensing or computation and is, to the best of our knowledge, the first high-framerate stereo detection system running onboard a small UAV.
Linear Intransitive Temporal Logic of Knowledge LTK_r, Decision Algorithms, Inference Rules
Venue: arXiv cs.LO 2014
Year: 2014

Our paper investigates the linear logic of knowledge and time LTK_r with reflexive intransitive time relation. The logic is defined semantically, -- as the set of formulas which are true at special frames with intransitive and reflexive time binary relation. The LTK_r -frames are linear chains of clusters connected by a reflexive intransitive relation $R_T$. Elements inside a cluster are connected by several equivalence relations imitating the knowledge of different agents. We study the decidability problem for formulas and inference rules. Decidability for formulas follows from decidability w.r.t. admissible inference rules.To study admissibility, we introduce some special constructive Kripke models useful for description of admissibility of inference rules. With a special technique of definable valuations we find an algorithm determining admissible inference rules in LTK_r. That is, we show that the logic LTK_r is decidable and decidable with respect to admissibility of inference rules.
Assigning channels via the meet-in-the-middle approach
Venue: arXiv cs.DS 2014
Year: 2014

We study the complexity of the Channel Assignment problem. By applying the meet-in-the-middle approach we get an algorithm for the $\ell$-bounded Channel Assignment (when the edge weights are bounded by $\ell$) running in time $O^*((2\sqrt{\ell+1})^n)$. This is the first algorithm which breaks the $(O(\ell))^n$ barrier. We extend this algorithm to the counting variant, at the cost of slightly higher polynomial factor. A major open problem asks whether Channel Assignment admits a $O(c^n)$-time algorithm, for a constant $c$ independent of $\ell$. We consider a similar question for Generalized T-Coloring, a CSP problem that generalizes \CA. We show that Generalized T-Coloring does not admit a $2^{2^{o\left(\sqrt{n}\right)}} {\rm poly}(r)$-time algorithm, where $r$ is the size of the instance.
Evidence with Uncertain Likelihoods
Venue: arXiv cs.AI 2014
Year: 2014

An agent often has a number of hypotheses, and must choose among them based on observations, or outcomes of experiments. Each of these observations can be viewed as providing evidence for or against various hypotheses. All the attempts to formalize this intuition up to now have assumed that associated with each hypothesis h there is a likelihood function μh, which is a probability measure that intuitively describes how likely each observation is, conditional on h being the correct hypothesis. We consider an extension of this framework where there is uncertainty as to which of a number of likelihood functions is appropriate, and discuss how one formal approach to defining evidence, which views evidence as a function from priors to posteriors, can be generalized to accommodate this uncertainty.
A Game-Theoretic Analysis of Updating Sets of Probabilities
Venue: arXiv cs.AI 2014
Year: 2014

We consider how an agent should update her uncertainty when it is represented by a set P of probability distributions and the agent observes that a random variable X takes on value x, given that the agent makes decisions using the minimax criterion, perhaps the best-studied and most commonly-used criterion in the literature. We adopt a game-theoretic framework, where the agent plays against a bookie, who chooses some distribution from P. We consider two reasonable games that differ in what the bookie knows when he makes his choice. Anomalies that have been observed before, like time inconsistency, can be understood as arising because different games are being played, against bookies with different information. We characterize the important special cases in which the optimal decision rules according to the minimax criterion amount to either conditioning or simply ignoring the information. Finally, we consider the relationship between conditioning and calibration when uncertainty is described by sets of probabilities.
On Spectrum Sharing Between Energy Harvesting Cognitive Radio Users and Primary Users
Venue: arXiv cs.NI 2014
Year: 2014

This paper investigates the maximum secondary throughput for a rechargeable secondary user (SU) sharing the spectrum with a primary user (PU) plugged to a reliable power supply. The SU maintains a finite energy queue and harvests energy from natural resources and primary radio frequency (RF) transmissions. We propose a power allocation policy at the PU and analyze its effect on the throughput of both the PU and SU. Furthermore, we study the impact of the bursty arrivals at the PU on the energy harvested by the SU from RF transmissions. Moreover, we investigate the impact of the rate of energy harvesting from natural resources on the SU throughput. We assume fading channels and compute exact closed-form expressions for the energy harvested by the SU under fading. Results reveal that the proposed power allocation policy along with the implemented RF energy harvesting at the SU enhance the throughput of both primary and secondary links.
Quickpie: An Interface for Fast and Accurate Eye Gazed based Text Entry
Venue: arXiv cs.HC 2014
Year: 2014

Pie menus are suggested as powerful tool for eye gaze based text entry among various interfaces developed so far. If pie menus are used with multiple depth layers then multiple saccades are required per selection of item, which is inefficient because it consumes more time. Also dwell time selection method is limited in performance because higher dwell time suffers from inefficiency while lower one from inaccuracy. To overcome problems with multiple depth layers and dwell time, we designed Quickpie, an interface for eye gaze based text entry with only one depth layer of pie menu and selection border as selection method instead of dwell time. We investigated various parameters like number of slices in pie menu, width characters and safe region, enlarged angle of slice and selection methods to achieve better performance. Our experiment results indicates that six number of slices with width of characters area 120 px performs better as compared to other designs.
Discovering Discriminative Cell Attributes for HEp-2 Specimen Image Classification
Venue: arXiv cs.CV 2014
Year: 2014

Recently, there has been a growing interest in developing Computer Aided Diagnostic (CAD) systems for improving the reliability and consistency of pathology test results. This paper describes a novel CAD system for the Anti-Nuclear Antibody (ANA) test via Indirect Immunofluorescence protocol on Human Epithelial Type 2 (HEp-2) cells. While prior works have primarily focused on classifying cell images extracted from ANA specimen images, this work takes a further step by focussing on the specimen image classification problem itself. Our system is able to efficiently classify specimen images as well as producing meaningful descriptions of ANA pattern class which helps physicians to understand the differences between various ANA patterns. We achieve this goal by designing a specimen-level image descriptor that: (1) is highly discriminative; (2) has small descriptor length and (3) is semantically meaningful at the cell level. In our work, a specimen image descriptor is represented by its overall cell attribute descriptors. As such, we propose two max-margin based learning schemes to discover cell attributes whilst still maintaining the discrimination of the specimen image descriptor. Our learning schemes differ from the existing discriminative attribute learning approaches as they primarily focus on discovering image-level attributes. Comparative evaluations were undertaken to contrast the proposed approach to various state-of-the-art approaches on a novel HEp-2 cell dataset which was specifically proposed for the specimen-level classification. Finally, we showcase the ability of the proposed approach to provide textual descriptions to explain ANA patterns.
A Digital Watermarking Approach Based on DCT Domain Combining QR Code and Chaotic Theory
Venue: arXiv cs.MM 2014
Year: 2014

This paper proposes a robust watermarking approach based on Discrete Cosine Transform domain that combines Quick Response Code and chaotic system.
A Taxonomy and Survey on eScience as a Service in the Cloud
Venue: arXiv cs.DC 2014
Year: 2014

Cloud computing has recently evolved as a popular computing infrastructure for many applications. Scientific computing, which was mainly hosted in private clusters and grids, has started to migrate development and deployment to the public cloud environment. eScience as a service becomes an emerging and promising direction for science computing. We review recent efforts in developing and deploying scientific computing applications in the cloud. In particular, we introduce a taxonomy specifically designed for scientific computing in the cloud, and further review the taxonomy with four major kinds of science applications, including life sciences, physics sciences, social and humanities sciences, and climate and earth sciences. Our major finding is that, despite existing efforts in developing cloud-based eScience, eScience still has a long way to go to fully unlock the power of cloud computing paradigm. Therefore, we present the challenges and opportunities in the future development of cloud-based eScience services, and call for collaborations and innovations from both the scientific and computer system communities to address those challenges.
Vertex 2-coloring without monochromatic cycles
Venue: arXiv cs.CC 2014
Year: 2014

In this paper we study a problem of vertex two-coloring of undirected graph such that there is no monochromatic cycle of given length. We show that this problem is hard to solve. We give a proof by presenting a reduction from variation of satisfiability (SAT) problem. We show nice properties of coloring cliques with two colors which plays pivotal role in the reduction construction.
Spectral and Energy Efficiency in 3-Way Relay Channels with Circular Message Exchanges
Venue: arXiv cs.IT 2014
Year: 2014

Spectral and energy efficiency in 3-way relay channels are studied in this paper. First, achievable sum rate expressions for 3-way relay channels are derived for different relaying protocols. Moreover, an outer bound for the capacity of the 3-way relay channel is presented. Next, leveraging the derived achievable sum rate expressions, two algorithms for joint power allocation at the users and at the relay are designed so as to maximize the system energy efficiency. Numerical results are provided to corroborate and provide insight on the theoretical findings.
An Optimal Game Theoretical Framework for Mobility Aware Routing in Mobile Ad hoc Networks
Venue: arXiv cs.NI 2014
Year: 2014

Selfish behaviors are common in self-organized Mobile Ad hoc Networks (MANETs) where nodes belong to different authorities. Since cooperation of nodes is essential for routing protocols, various methods have been proposed to stimulate cooperation among selfish nodes. In order to provide sufficient incentives, most of these methods pay nodes a premium over their actual costs of participation. However, they lead to considerably large overpayments. Moreover, existing methods ignore mobility of nodes, for simplicity. However, owing to the mobile nature of MANETs, this assumption seems unrealistic. In this paper, we propose an optimal game theoretical framework to ensure the proper cooperation in mobility aware routing for MANETs. The proposed method is based on the multi-dimensional optimal auctions which allows us to consider path durations, in addition to the route costs. Path duration is a metric that best reflects changes in topology caused by mobility of nodes and, it is widely used in mobility aware routing protocols. Furthermore, the proposed mechanism is optimal in that it minimizes the total expected payments. We provide theoretical analysis to support our claims. In addition, simulation results show significant improvements in terms of payments compared to the most popular existing methods.