The Experts below are selected from a list of 13266 Experts worldwide ranked by ideXlab platform
Bhargab B. Bhattacharya - One of the best experts on this subject based on the ideXlab platform.
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A Fast and Automated Granulometric Image Analysis Based on Digital Geometry
Fundamenta Informaticae, 2015Co-Authors: Sahadev Bera, Arindam Biswas, Bhargab B. BhattacharyaAbstract:Granular object segmentation is an important area of image processing, which has several practical applications in agriculture, food industry, geology, and forensics. In this paper, we present a simple algorithm for the analysis of granulometric images that consist of touching or overlapping convex objects such as coffee bean, food grain, nuts, blood cell, or cookies. The algorithm is based on certain underlying digital-geometric features embedded in their binary snapshots. The concept of an outer isothetic cover and the property of geometric convexity are used to extract the joining points or concavity points from the ensemble of objects. Next, a combinatorial technique is employed to determine the separator of two overlapping or neighboring objects. This technique is fully automated and it needs only Integer-Domain computation. The termination time of the algorithm can be traded-off with the quality of segmentation by changing the resolution parameter. Experimental results for a variety of objects chosen from different application Domains such as cell image, coffee-bean image and others demonstrate the efficiency and robustness of the proposed method compared to earlier watershed-based algorithms.
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a linear time combinatorial algorithm to find the orthogonal hull of an object on the digital plane
Information Sciences, 2012Co-Authors: Arindam Biswas, Partha Bhowmick, Moumita Sarkar, Bhargab B. BhattacharyaAbstract:A combinatorial algorithm to compute the orthogonal hull of a digital object imposed on a background grid is presented in this paper. The resolution and complexity of the orthogonal hull can be controlled by varying the grid size, which may be used for a multiresolution analysis of a given object. Existing algorithms on finding the convex hull are based on divide and conquer strategy, sweepline approach, etc., whereas the proposed algorithm is combinatorial in nature whose time complexity is linear on the object perimeter instead of the object area. For a larger grid size, the perimeter of an object decreases in length in terms of grid units, and hence the runtime of the algorithm reduces significantly. The algorithm uses only comparison and addition in the Integer Domain, thereby making it amenable to usage in real-world applications where speed is a prime factor. Experimental results including the CPU time demonstrate the elegance and efficacy of the proposed algorithm.
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On finding an orthogonal convex skull of a digital object
International Journal of Imaging Systems and Technology, 2011Co-Authors: Mousumi Dutt, Arindam Biswas, Partha Bhowmick, Bhargab B. BhattacharyaAbstract:A combinatorial algorithm to compute an orthogonal convex skull of a digital object imposed on the background grid is presented in this paper. The proposed algorithm has the time complexity of O(n log n), which improves the earlier method of O(n2) time complexity for finding the convex skull of a simple orthogonal polygon. A set of rules is formulated first and then an orthogonal convex skull is derived by applying these rules while traversing along the boundary of the inner orthogonal polygon that tightly inscribes the given digital object. The algorithm uses only comparison and addition in the Integer Domain, which makes it amenable to fast real-world applications. Experimental results on different shapes have also been presented to demonstrate the efficacy and elegance of the proposed technique. © 2011 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 21, 14–27, 2011.
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IWCIA - Construction of 3D orthogonal cover of a digital object
Lecture Notes in Computer Science, 2011Co-Authors: Nilanjana Karmakar, Arindam Biswas, Partha Bhowmick, Bhargab B. BhattacharyaAbstract:The orthogonal cover of a 3D digital object is a minimum-volume 3D polytope having surfaces parallel to the coordinate planes, and containing the entire object so as to capture its approximate shape information. An efficient algorithm for construction of such an orthogonal cover imposed on a background grid is presented in this paper. A combinatorial technique is used to classify the grid faces constituting the polytope while traversing along the surface of the object in a breadthfirst manner. The eligible grid faces are stored in a doubly connected edge list, using which the faces are finally merged to derive the isothetic polygons parallel to the coordinate planes, thereby obtaining the orthogonal cover of the object. The complexity of the cover decreases with increasing grid size. The algorithm requires computations in Integer Domain only and runs in a time linear in the number of voxels constituting the object surface. Experimental results demonstrate the effectiveness of the algorithm.
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ICFHR - Word Segmentation and Baseline Detection in Handwritten Documents Using Isothetic Covers
2010 12th International Conference on Frontiers in Handwriting Recognition, 2010Co-Authors: Aisharjya Sarkar, Arindam Biswas, Partha Bhowmick, Bhargab B. BhattacharyaAbstract:A novel approach towards word segmentation and baseline detection in a handwritten document is proposed. It is based on certain structural properties of isothetic covers tightly enclosing the words in a handwritten document. For an appropriate grid size, the isothetic covers successfully segregates the words so that each cover corresponds to a particular word. By analyzing the horizontal chords of these covers, the corresponding baselines are extracted. The method is fast, robust, and efficient by dint of its traversal strategy along the word boundaries in a combinatorial manner and usage of limited operations strictly in the Integer Domain. Some results on several Bengali and English handwritings have been given to demonstrate its strength and elegance.
Houbin Song - One of the best experts on this subject based on the ideXlab platform.
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A Fitness Landscape Analysis for the No-Wait Flow Shop Scheduling Problem With Factorial Representation
IEEE Access, 2019Co-Authors: Fuqing Zhao, Feilong Xue, Guoqiang Yang, Chuck Zhang, Houbin SongAbstract:The no-wait flow shop scheduling problem (NWFSP) is one of the essential models in the manufacturing systems. In this paper, the fitness landscape of the factorial representation for NWFSP with the makespan criterion is studied. The encoding and decoding schemes based on the factorial representation are constructed to transfer the permutation Domain to the Integer Domain. The position-type distributions and fitness distance correlation are implemented to analyze the fitness landscape of the classic benchmarks. The multiple big valleys’ structure in the fitness landscape is confirmed through the observation of fitness distance plot and the analysis of factorial coding theory. The various local optima and high ruggedness of the fitness landscape are visualized through the statistical results of position-type distributions. The results of fitness landscape analysis show the suitability of the landscape for the searchability with evolutionary algorithms and local search methods for solving NWFSP.
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A factorial based particle swarm optimization with a population adaptation mechanism for the no-wait flow shop scheduling problem with the makespan objective
Expert Systems with Applications, 2019Co-Authors: Fuqing Zhao, Guoqiang Yang, Chuck Zhang, Shuo Qin, Houbin SongAbstract:Abstract The no-wait flow shop scheduling problem (NWFSP) performs an essential role in the manufacturing industry. In this paper, a factorial based particle swarm optimization with a population adaptation mechanism (FPAPSO) is implemented for solving the NWFSP with the makespan criterion. The nearest neighbor mechanism and NEH method are employed to generate a potential initial population. The factorial representation, which uniquely represents each number as a string of factorial digits, is designed to transfer the permutation Domain to the Integer Domain. A variable neighbor search strategy based on the insert and swap neighborhood structure is introduced to perform a local search around the current best solution. A population adaptation (PA) mechanism is designed to control the diversity of the population and to avoid the particles being trapped into local optima. Furthermore, a runtime analysis of FPAPSO is performed with the level-based theorem. The computational results and comparisons with other state-of-the-art algorithms based on the Reeve's and Taillard's instances demonstrate the efficiency and performance of FPAPSO for solving the NWFSP.
Peter J. Stuckey - One of the best experts on this subject based on the ideXlab platform.
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ESOP - Size-Change termination analysis in k -bits
Programming Languages and Systems, 2006Co-Authors: Michael Codish, Vitaly Lagoon, Peter Schachte, Peter J. StuckeyAbstract:Size-change termination analysis is a simple and powerful technique successfully applied for a variety of programming paradigms. A main advantage is that termination for size-change graphs is decidable and based on simple linear ranking functions. A main disadvantage is that the size-change termination problem is PSPACE-complete. Proving size change termination may have to consider exponentially many size change graphs. This paper is concerned with the representation of large sets of size-change graphs. The approach is constraint based and the novelty is that sets of size-change graphs are represented as disjunctions of size-change constraints. A constraint solver to facilitate size-change termination analysis is obtained by interpreting size-change constraints over a sufficiently large but finite non-negative Integer Domain. A Boolean k-bit modeling of size change graphs using binary decision diagrams leads to a concise representation. Experimental evaluation indicates that the 2-bit representation facilitates an efficient implementation which is guaranteed complete for our entire benchmark suite.
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Australian Conference on Artificial Intelligence - Finite Domain bounds consistency revisited
Lecture Notes in Computer Science, 2006Co-Authors: Chiu Wo Choi, Warwick Harvey, Jimmy H. M. Lee, Peter J. StuckeyAbstract:A widely adopted approach to solving constraint satisfaction problems combines systematic tree search with constraint propagation for pruning the search space. Constraint propagation is performed by propagators implementing a certain notion of consistency. Bounds consistency is the method of choice for building propagators for arithmetic constraints and several global constraints in the finite Integer Domain. However, there has been some confusion in the definition of bounds consistency and of bounds propagators. We clarify the differences among the three commonly used notions of bounds consistency in the literature. This serves as a reference for implementations of bounds propagators by defining (for the first time) the a priori behavior of bounds propagators on arbitrary constraints.
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Finite Domain Bounds Consistency Revisited
arXiv: Artificial Intelligence, 2004Co-Authors: Chiu Wo Choi, Warwick Harvey, Jimmy H. M. Lee, Peter J. StuckeyAbstract:A widely adopted approach to solving constraint satisfaction problems combines systematic tree search with constraint propagation for pruning the search space. Constraint propagation is performed by propagators implementing a certain notion of consistency. Bounds consistency is the method of choice for building propagators for arithmetic constraints and several global constraints in the finite Integer Domain. However, there has been some confusion in the definition of bounds consistency. In this paper we clarify the differences and similarities among the three commonly used notions of bounds consistency.
Wonyong Sung - One of the best experts on this subject based on the ideXlab platform.
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Fixed-point error analysis and word length optimization of 8/spl times/8 IDCT architectures
IEEE Transactions on Circuits and Systems for Video Technology, 1998Co-Authors: Seehyun Kim, Wonyong SungAbstract:Complete fixed-point error models that include the coefficient quantization are derived for two popular 8/spl times/8 two-dimensional (2-D) IDCT architectures; one is based on distributed arithmetic, and the other is the multiplier-adder chain. The error models are evaluated in the Integer Domain to accurately measure the effects of rounding. The analysis results show that the overall mean-square error performance (OMSE) is the most critical condition for meeting the IEEE specification (IEEE Std. 1180-1990) when the rounding scheme is employed. On the other hand, the mean error effects (OME and PME) are dominant for truncation. Finally, the analysis results are compared with those of bit-accurate simulation.
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Fixed-point error analysis and wordlength optimization of a distributed arithmetic based 8/spl times/8 2D-IDCT architecture
VLSI Signal Processing IX, 1Co-Authors: Seehyun Kim, Wonyong SungAbstract:The two dimensional discrete cosine transform (DCT) has been used widely for various image and video processing standards. Efficient implementation of the algorithm requires fixed-point arithmetic, which may result in a noticeable mismatch between the encoder and the decoder. The finite wordlength effects of a distributed arithmetic based 8/spl times/8 2D-IDCT (inverse discrete cosine transform) are analytically modeled. In order to accurately model the implementation hardware, the ensemble average of Integer Domain fixed-point errors after rounding is evaluated not only by calculating the mean and the variance but by considering the statistical distribution as well. Based on the error model, a set of optimum wordlengths conforming to the IEEE specifications is determined. There is a close agreement between the model and the bit-accurate simulation results.
Amir M. Ben-amram - One of the best experts on this subject based on the ideXlab platform.
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Monotonicity Constraints for Termination in the Integer Domain
Logical Methods in Computer Science, 2011Co-Authors: Amir M. Ben-amramAbstract:Size-Change Termination (SCT) is a method of proving program termination based on the impossibility of infinite descent. To this end we use a program abstraction in which transitions are described by Monotonicity Constraints over (abstract) variables. When only constraints of the form x>y' and x\geq y' are allowed, we have size-change graphs. In the last decade, both theory and practice have evolved significantly in this restricted framework. The crucial underlying assumption of most of the past work is that the Domain of the variables is well-founded. In a recent paper I showed how to extend and adapt some theory from the Domain of size-change graphs to general monotonicity constraints, thus complementing previous work, but remaining in the realm of well-founded Domains. However, monotonicity constraints are, interestingly, capable of proving termination also in the Integer Domain, which is not well-founded. The purpose of this paper is to explore the application of monotonicity constraints in this Domain. We lay the necessary theoretical foundation, and present precise decision procedures for termination; finally, we provide a procedure to construct explicit global ranking functions from monotonicity constraints in singly-exponential time, and of optimal worst-case size and dimension (ordinal).
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SAT-based termination analysis using monotonicity constraints over the Integers
Theory and Practice of Logic Programming, 2011Co-Authors: Michael Codish, Amir M. Ben-amram, Igor Gonopolskiy, Carsten Fuhs, Jürgen GieslAbstract:We describe an algorithm for proving termination of programs abstracted to systems of monotonicity constraints in the Integer Domain. Monotonicity constraints are a nontrivial extension of the well-known size-change termination method. While deciding termination for systems of monotonicity constraints is PSPACE complete, we focus on a well-defined and significant subset, which we call MCNP (for “monotonicity constraints in NP”), designed to be amenable to a SAT-based solution. Our technique is based on the search for a special type of ranking function defined in terms of bounded differences between multisets of Integer values. We describe the application of our approach as the back end for the termination analysis of Java Bytecode. At the front end, systems of monotonicity constraints are obtained by abstracting information, using two different termination analyzers: AProVE and COSTA . Preliminary results reveal that our approach provides a good trade-off between precision and cost of analysis.
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CAV - Size-Change Termination, Monotonicity Constraints and Ranking Functions
Computer Aided Verification, 2009Co-Authors: Amir M. Ben-amramAbstract:Size-change termination involves deducing program termination based on the impossibility of infinite descent. To this end we may use a program abstraction in which transitions are described by monotonicity constraints over (abstract) variables. When only constraints of the form x > y *** and x *** y *** are allowed, we have size-change graphs, for which both theory and practice are now more evolved then for general monotonicity constraints. This work shows that it is possible to transfer some theory from the Domain of size-change graphs to the general case, complementing and extending previous work on monotonicity constraints. Significantly, we provide a procedure to construct explicit global ranking functions from monotonicity constraints in singly-exponential time, which is better than what has been published so far even for size-change graphs. We also consider the Integer Domain, where general monotonicity constraints are essential because the Domain is not well-founded.
