This paper discusses the design and application of local search methods to a real-life application at a steel cord manufacturing plant. The case study involves a layout problem that can be represented as a Quadratic Assignment Problem (QAP). Due to the nature of the manufacturing process, certain machinery need to be allocated in close proximity to each other. This issue is incorporated into the objective function through assigning high penalty costs to the unfavorable allocations. QAP belongs to one of the most difficult class of combinatorial optimization problems, and is not solvable to optimality as the number of facilities increases. We implement the well-known local
search methods, 2-opt, 3-opt and tabu search. We compare the solution performances of the methods to the results obtained from the NEOS server, which provides free access to many optimization solvers on the internet.
http://research.sabanciuniv.edu.
Application Of Local Search Methods For Solving A Quadratic Assignment Probl...ertekg
Download Link > https://ertekprojects.com/gurdal-ertek-publications/blog/application-of-local-search-methods-for-solving-a-quadratic-assignment-problem-a-case-study/
This paper discusses the design and application of local search methods to a real-life application at a steel cord manufacturing plant. The case study involves a layout problem that can be represented as a Quadratic Assignment Problem (QAP). Due to the nature of the manufacturing process, certain machinery need to be allocated in close proximity to each other. This issue is incorporated into the objective function through assigning high penalty costs to the unfavorable allocations. QAP belongs to one of the most difficult class of combinatorial optimization problems, and is not solvable to optimality as the number of facilities increases. We implement the well-known local search methods, 2-opt, 3-opt and tabu search. We compare the solution performances of the methods to the results obtained from the NEOS server, which provides free access to many optimization solvers on the internet.
Comparative study to realize an automatic speaker recognition system IJECEIAES
In this research, we present an automatic speaker recognition system based on adaptive orthogonal transformations. To obtain the informative features with a minimum dimension from the input signals, we created an adaptive operator, which helped to identify the speaker’s voice in a fast and efficient manner. We test the efficiency and the performance of our method by comparing it with another approach, mel-frequency cepstral coefficients (MFCCs), which is widely used by researchers as their feature extraction method. The experimental results show the importance of creating the adaptive operator, which gives added value to the proposed approach. The performance of the system achieved 96.8% accuracy using Fourier transform as a compression method and 98.1% using Correlation as a compression method.
Application of Multiple Kernel Support Vector Regression for Weld Bead Geomet...IJECEIAES
Modelling and prediction of weld bead geometry is an important issue in robotic GMAW process. This process is highly non-linear and coupled multivariable system and the relationship between process parameters and weld bead geometry cannot be defined by an explicit mathematical expression. Therefore, application of supervised learning algorithms can be useful for this purpose. Support vector machine is a very successful approach to supervised learning. In this approach, a higher degree of accuracy and generalization capability can be obtained by using the multiple kernel learning framework, which is considered as a great advantage in prediction of weld bead geometry due to the high degree of prediction accuracy required. In this paper, a novel approach for modelling and prediction of the weld bead geometry, based on multiple kernel support vector regression analysis has been proposed, which benefits from a high degree of accuracy and generalization capability. This model can be used for proper selection of welding parameters in order to obtain a desired weld bead geometry in robotic GMAW process.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Artificial Intelligence based optimization of weld bead geometry in laser wel...IJMER
This paper reports on a modeling and optimization of laser welding of aluminum-magnesium alloy thickness of 1.7mm. Regression analysis is used for modeling and Genetic algorithm is used for optimize the process parameters.The input values for the regression methods is taken according the Taguchi based orthogonal array. A software named Computer aided Robust Parameter Genetic Algorithm CARPGA has been developed in MATLAB 2013 which combine all of these methodologies. This software has been validated with some published paper.
Application Of Local Search Methods For Solving A Quadratic Assignment Probl...ertekg
Download Link > https://ertekprojects.com/gurdal-ertek-publications/blog/application-of-local-search-methods-for-solving-a-quadratic-assignment-problem-a-case-study/
This paper discusses the design and application of local search methods to a real-life application at a steel cord manufacturing plant. The case study involves a layout problem that can be represented as a Quadratic Assignment Problem (QAP). Due to the nature of the manufacturing process, certain machinery need to be allocated in close proximity to each other. This issue is incorporated into the objective function through assigning high penalty costs to the unfavorable allocations. QAP belongs to one of the most difficult class of combinatorial optimization problems, and is not solvable to optimality as the number of facilities increases. We implement the well-known local search methods, 2-opt, 3-opt and tabu search. We compare the solution performances of the methods to the results obtained from the NEOS server, which provides free access to many optimization solvers on the internet.
Comparative study to realize an automatic speaker recognition system IJECEIAES
In this research, we present an automatic speaker recognition system based on adaptive orthogonal transformations. To obtain the informative features with a minimum dimension from the input signals, we created an adaptive operator, which helped to identify the speaker’s voice in a fast and efficient manner. We test the efficiency and the performance of our method by comparing it with another approach, mel-frequency cepstral coefficients (MFCCs), which is widely used by researchers as their feature extraction method. The experimental results show the importance of creating the adaptive operator, which gives added value to the proposed approach. The performance of the system achieved 96.8% accuracy using Fourier transform as a compression method and 98.1% using Correlation as a compression method.
Application of Multiple Kernel Support Vector Regression for Weld Bead Geomet...IJECEIAES
Modelling and prediction of weld bead geometry is an important issue in robotic GMAW process. This process is highly non-linear and coupled multivariable system and the relationship between process parameters and weld bead geometry cannot be defined by an explicit mathematical expression. Therefore, application of supervised learning algorithms can be useful for this purpose. Support vector machine is a very successful approach to supervised learning. In this approach, a higher degree of accuracy and generalization capability can be obtained by using the multiple kernel learning framework, which is considered as a great advantage in prediction of weld bead geometry due to the high degree of prediction accuracy required. In this paper, a novel approach for modelling and prediction of the weld bead geometry, based on multiple kernel support vector regression analysis has been proposed, which benefits from a high degree of accuracy and generalization capability. This model can be used for proper selection of welding parameters in order to obtain a desired weld bead geometry in robotic GMAW process.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Artificial Intelligence based optimization of weld bead geometry in laser wel...IJMER
This paper reports on a modeling and optimization of laser welding of aluminum-magnesium alloy thickness of 1.7mm. Regression analysis is used for modeling and Genetic algorithm is used for optimize the process parameters.The input values for the regression methods is taken according the Taguchi based orthogonal array. A software named Computer aided Robust Parameter Genetic Algorithm CARPGA has been developed in MATLAB 2013 which combine all of these methodologies. This software has been validated with some published paper.
The Application Of Bayes Ying-Yang Harmony Based Gmms In On-Line Signature Ve...ijaia
In this contribution, a Bayes Ying-Yang(BYY) harmony based approach for on-line signature verification is
presented. In the proposed method, a simple but effective Gaussian Mixture Models(GMMs) is used to
represent for each user’s signature model based on the prior information collected. Different from the early
works, in this paper, we use the Bayes Ying Yang machine combined with the harmony function to achieve
Automatic Model Selection(AMS) during the parameter learning for the GMMs, so that a better
approximation of the user model is assured. Experiments on a database from the First International
Signature Verification Competition(SVC 2004) confirm that this combined algorithm yields quite a
satisfactory result.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
An efficient hardware logarithm generator with modified quasi-symmetrical app...IJECEIAES
This paper presents a low-error, low-area FPGA-based hardware logarithm generator for digital signal processing systems which require high-speed, real time logarithm operations. The proposed logarithm generator employs the modified quasi-symmetrical approach for an efficient hardware implementation. The error analysis and implementation results are also presented and discussed. The achieved results show that the proposed approach can reduce the approximation error and hardware area compared with traditional methods.
A Weighted Duality based Formulation of MIMO SystemsIJERA Editor
This work is based on the modeling and analysis of multiple-input multiple-output (MIMO) system in downlink communication system. We take into account a recent work on the ratio of quadratic forms to formulate the weight matrices of quadratic norm in a duality structure. This enables us to achieve exact solutions for MIMO system operating under Rayleigh fading channels. We outline couple of scenarios dependent on the structure of eigenvalues to investigate the system behavior. The results obtained are validated by means of Monte Carlo simulations.
Macromodel of High Speed Interconnect using Vector Fitting Algorithmijsrd.com
At high frequency efficient macromodeling of high speed interconnects is all time challenging task. We have presented systematic methodologies to generate rational function approximations of high-speed interconnects using vector fitting technique for any type of termination conditions and construct efficient multiport model, which is easily and directly compatible with circuit simulators.
Image Segmentation Using Two Weighted Variable Fuzzy K MeansEditor IJCATR
Image segmentation is the first step in image analysis and pattern recognition. Image segmentation is the process of dividing an image into different regions such that each region is homogeneous. The accurate and effective algorithm for segmenting image is very useful in many fields, especially in medical image. This paper presents a new approach for image segmentation by applying k-means algorithm with two level variable weighting. In image segmentation, clustering algorithms are very popular as they are intuitive and are also easy to implement. The K-means and Fuzzy k-means clustering algorithm is one of the most widely used algorithms in the literature, and many authors successfully compare their new proposal with the results achieved by the k-Means and Fuzzy k-Means. This paper proposes a new clustering algorithm called TW-fuzzy k-means, an automated two-level variable weighting clustering algorithm for segmenting object. In this algorithm, a variable weight is also assigned to each variable on the current partition of data. This could be applied on general images and/or specific images (i.e., medical and microscopic images). The proposed TW-Fuzzy k-means algorithm in terms of providing a better segmentation performance for various type of images. Based on the results obtained, the proposed algorithm gives better visual quality as compared to several other clustering methods.
A Novel Algorithm for Watermarking and Image Encryption cscpconf
Digital watermarking is a method of copyright protection of audio, images, video and text. We
propose a new robust watermarking technique based on contourlet transform and singular value
decomposition. The paper also proposes a novel encryption algorithm to store a signed double
matrix as an RGB image. The entropy of the watermarked image and correlation coefficient of
extracted watermark image is very close to ideal values, proving the correctness of proposed
algorithm. Also experimental results show resiliency of the scheme against large blurring attack
like mean and gaussian filtering, linear filtering (high pass and low pass filtering) , non-linear
filtering (median filtering), addition of a constant offset to the pixel values and local exchange of pixels .Thus proving the security, effectiveness and robustness of the proposed watermarking algorithm.
A Fast Floating Point Double Precision Implementation on FpgaIJERA Editor
In the modern day digital systems, floating point units are an important component in many signal and image
processing applications. Many approaches of the floating point units have been proposed and compared with
their counterparts in recent years. IEEE 754 floating point standard allows two types of precision units for
floating point operations, single and double. In the proposed architecture double precision floating point unit is
used and basic arithmetic operations are performed. A parallel architecture is proposed along with the high
speed adder, which is shared among other operations and can perform operations independently as a separate
unit. To improve the area efficiency of the unit, carry select adder is designed with the novel resource sharing
technique which allows performing the operations with the minimum usage of the resources while computing
the carry and sum for „0‟ and „1‟. The design is implemented using the Xilinx Spartan 6 FPGA and the results
show the 23% improvement in the speed of the designed circuit
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Medical image analysis and processing using a dual transformeSAT Journals
Abstract The demand for images in medical field has increased drastically over the years. The need for reducing the storage space has resulted in image compression. This paper presents a dual transform for medical image compression algorithm. The experimental results determines how the compression ratio (CR), peak signal to noise ratio (PSNR) and SNR (signal to noise ratio) of different compression algorithms responds to dual transform algorithm. Keywords: DCT, SPIHT, Haar Wavelet, Linear approximation transform, image compression, Singular Value Decomposition (SVD).
In stereo vision, the epipolar geometry is the intrinsic projective geometry between the two views. The
essential and fundamental matrices relate corresponding points in stereo images. The essential matrix
describes the geometry when the used cameras are calibrated, and the fundamental matrix expresses the
geometry when the cameras are uncalibrated. Since the nineties, researchers devoted a lot of effort to
estimate the fundamental matrix. Although it is a landmark of computer vision, in the current work, three
derivations of the essential and fundamental matrices have been revised. The Longuet-Higgins' derivation
of the essential matrix where he draws a mapping between the position vectors of a 3D point; however, the
one-to-one feature of that mapping is lost when he changed it to a relation between the image points. In the
two other derivations, we demonstrate that the authors established a mapping between the image points
through the misuse of mathematics.
Real-time traffic sign detection and recognition using Raspberry Pi IJECEIAES
Nowadays, the number of road accident in Malaysia is increasing expeditiously. One of the ways to reduce the number of road accident is through the development of the advanced driving assistance system (ADAS) by professional engineers. Several ADAS system has been proposed by taking into consideration the delay tolerance and the accuracy of the system itself. In this work, a traffic sign recognition system has been developed to increase the safety of the road users by installing the system inside the car for driver’s awareness. TensorFlow algorithm has been considered in this work for object recognition through machine learning due to its high accuracy. The algorithm is embedded in the Raspberry Pi 3 for processing and analysis to detect the traffic sign from the real-time video recording from Raspberry Pi camera NoIR. This work aims to study the accuracy, delay and reliability of the developed system using a Raspberry Pi 3 processor considering several scenarios related to the state of the environment and the condition of the traffic signs. A real-time testbed implementation has been conducted considering twenty different traffic signs and the results show that the system has more than 90% accuracy and is reliable with an acceptable delay.
Application of local search methods for solving a quadratic assignment proble...ertekg
Ertek, G., Aksu, B., Birbil, S. E., İkikat, M. C., Yıldırmaz, C. (2005). “Application of local search methods for solving a quadratic assignment problem: A case study”, Proceedings of Computers and Industrial Engineering Conference, 2005. Istanbul, Turkey.
ADVANCED ALGORITHMS FOR ETCHING SIMULATION OF 3D MEMS-TUNABLE LASERSijctcm
This The integrated circuits (ICs) industry uses a number of technology computer aided design (TCAD)
software tools to simulate the manufacturing and the operation of many ICs at different levels. At very low
level, the simulation tools are used to simulate the device fabrication and design. These simulation tools
are based on solving mathematical equations that describe the physics of dopant diffusion, silicon
oxidation, etching, deposition, lithography, implantation, and metallization. The simulation of physical
etching solves etching equations to calculate the etching rate. And this rate is used to move the geometry
of the device. The simulation of non-physical (geometrical) etching is based on geometrical Boolean
operations. In this paper, we are proposing new and advanced geometrical etching algorithms for the
process simulation of three dimensional (3D) micro electro mechanical systems (MEMS) and MEMStunable
vertical cavity semiconductor optical amplifiers (VCSOAs). These algorithms are based on
advanced domain decomposition methods, Delaunay meshing algorithms, and surface re-meshing and
smoothing techniques. These algorithms are simple, robust, and significantly reduce the overall run time
of the process simulation of 3D MEMS and MEMS-tunable laser devices. The description of the proposed
etching algorithms will be presented. Numerical simulation results showing the performances of these
algorithms will be given and analyzed for realistic 3D MEMS and MEMS-tunable laser devices.
The Application Of Bayes Ying-Yang Harmony Based Gmms In On-Line Signature Ve...ijaia
In this contribution, a Bayes Ying-Yang(BYY) harmony based approach for on-line signature verification is
presented. In the proposed method, a simple but effective Gaussian Mixture Models(GMMs) is used to
represent for each user’s signature model based on the prior information collected. Different from the early
works, in this paper, we use the Bayes Ying Yang machine combined with the harmony function to achieve
Automatic Model Selection(AMS) during the parameter learning for the GMMs, so that a better
approximation of the user model is assured. Experiments on a database from the First International
Signature Verification Competition(SVC 2004) confirm that this combined algorithm yields quite a
satisfactory result.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
An efficient hardware logarithm generator with modified quasi-symmetrical app...IJECEIAES
This paper presents a low-error, low-area FPGA-based hardware logarithm generator for digital signal processing systems which require high-speed, real time logarithm operations. The proposed logarithm generator employs the modified quasi-symmetrical approach for an efficient hardware implementation. The error analysis and implementation results are also presented and discussed. The achieved results show that the proposed approach can reduce the approximation error and hardware area compared with traditional methods.
A Weighted Duality based Formulation of MIMO SystemsIJERA Editor
This work is based on the modeling and analysis of multiple-input multiple-output (MIMO) system in downlink communication system. We take into account a recent work on the ratio of quadratic forms to formulate the weight matrices of quadratic norm in a duality structure. This enables us to achieve exact solutions for MIMO system operating under Rayleigh fading channels. We outline couple of scenarios dependent on the structure of eigenvalues to investigate the system behavior. The results obtained are validated by means of Monte Carlo simulations.
Macromodel of High Speed Interconnect using Vector Fitting Algorithmijsrd.com
At high frequency efficient macromodeling of high speed interconnects is all time challenging task. We have presented systematic methodologies to generate rational function approximations of high-speed interconnects using vector fitting technique for any type of termination conditions and construct efficient multiport model, which is easily and directly compatible with circuit simulators.
Image Segmentation Using Two Weighted Variable Fuzzy K MeansEditor IJCATR
Image segmentation is the first step in image analysis and pattern recognition. Image segmentation is the process of dividing an image into different regions such that each region is homogeneous. The accurate and effective algorithm for segmenting image is very useful in many fields, especially in medical image. This paper presents a new approach for image segmentation by applying k-means algorithm with two level variable weighting. In image segmentation, clustering algorithms are very popular as they are intuitive and are also easy to implement. The K-means and Fuzzy k-means clustering algorithm is one of the most widely used algorithms in the literature, and many authors successfully compare their new proposal with the results achieved by the k-Means and Fuzzy k-Means. This paper proposes a new clustering algorithm called TW-fuzzy k-means, an automated two-level variable weighting clustering algorithm for segmenting object. In this algorithm, a variable weight is also assigned to each variable on the current partition of data. This could be applied on general images and/or specific images (i.e., medical and microscopic images). The proposed TW-Fuzzy k-means algorithm in terms of providing a better segmentation performance for various type of images. Based on the results obtained, the proposed algorithm gives better visual quality as compared to several other clustering methods.
A Novel Algorithm for Watermarking and Image Encryption cscpconf
Digital watermarking is a method of copyright protection of audio, images, video and text. We
propose a new robust watermarking technique based on contourlet transform and singular value
decomposition. The paper also proposes a novel encryption algorithm to store a signed double
matrix as an RGB image. The entropy of the watermarked image and correlation coefficient of
extracted watermark image is very close to ideal values, proving the correctness of proposed
algorithm. Also experimental results show resiliency of the scheme against large blurring attack
like mean and gaussian filtering, linear filtering (high pass and low pass filtering) , non-linear
filtering (median filtering), addition of a constant offset to the pixel values and local exchange of pixels .Thus proving the security, effectiveness and robustness of the proposed watermarking algorithm.
A Fast Floating Point Double Precision Implementation on FpgaIJERA Editor
In the modern day digital systems, floating point units are an important component in many signal and image
processing applications. Many approaches of the floating point units have been proposed and compared with
their counterparts in recent years. IEEE 754 floating point standard allows two types of precision units for
floating point operations, single and double. In the proposed architecture double precision floating point unit is
used and basic arithmetic operations are performed. A parallel architecture is proposed along with the high
speed adder, which is shared among other operations and can perform operations independently as a separate
unit. To improve the area efficiency of the unit, carry select adder is designed with the novel resource sharing
technique which allows performing the operations with the minimum usage of the resources while computing
the carry and sum for „0‟ and „1‟. The design is implemented using the Xilinx Spartan 6 FPGA and the results
show the 23% improvement in the speed of the designed circuit
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Medical image analysis and processing using a dual transformeSAT Journals
Abstract The demand for images in medical field has increased drastically over the years. The need for reducing the storage space has resulted in image compression. This paper presents a dual transform for medical image compression algorithm. The experimental results determines how the compression ratio (CR), peak signal to noise ratio (PSNR) and SNR (signal to noise ratio) of different compression algorithms responds to dual transform algorithm. Keywords: DCT, SPIHT, Haar Wavelet, Linear approximation transform, image compression, Singular Value Decomposition (SVD).
In stereo vision, the epipolar geometry is the intrinsic projective geometry between the two views. The
essential and fundamental matrices relate corresponding points in stereo images. The essential matrix
describes the geometry when the used cameras are calibrated, and the fundamental matrix expresses the
geometry when the cameras are uncalibrated. Since the nineties, researchers devoted a lot of effort to
estimate the fundamental matrix. Although it is a landmark of computer vision, in the current work, three
derivations of the essential and fundamental matrices have been revised. The Longuet-Higgins' derivation
of the essential matrix where he draws a mapping between the position vectors of a 3D point; however, the
one-to-one feature of that mapping is lost when he changed it to a relation between the image points. In the
two other derivations, we demonstrate that the authors established a mapping between the image points
through the misuse of mathematics.
Real-time traffic sign detection and recognition using Raspberry Pi IJECEIAES
Nowadays, the number of road accident in Malaysia is increasing expeditiously. One of the ways to reduce the number of road accident is through the development of the advanced driving assistance system (ADAS) by professional engineers. Several ADAS system has been proposed by taking into consideration the delay tolerance and the accuracy of the system itself. In this work, a traffic sign recognition system has been developed to increase the safety of the road users by installing the system inside the car for driver’s awareness. TensorFlow algorithm has been considered in this work for object recognition through machine learning due to its high accuracy. The algorithm is embedded in the Raspberry Pi 3 for processing and analysis to detect the traffic sign from the real-time video recording from Raspberry Pi camera NoIR. This work aims to study the accuracy, delay and reliability of the developed system using a Raspberry Pi 3 processor considering several scenarios related to the state of the environment and the condition of the traffic signs. A real-time testbed implementation has been conducted considering twenty different traffic signs and the results show that the system has more than 90% accuracy and is reliable with an acceptable delay.
Application of local search methods for solving a quadratic assignment proble...ertekg
Ertek, G., Aksu, B., Birbil, S. E., İkikat, M. C., Yıldırmaz, C. (2005). “Application of local search methods for solving a quadratic assignment problem: A case study”, Proceedings of Computers and Industrial Engineering Conference, 2005. Istanbul, Turkey.
ADVANCED ALGORITHMS FOR ETCHING SIMULATION OF 3D MEMS-TUNABLE LASERSijctcm
This The integrated circuits (ICs) industry uses a number of technology computer aided design (TCAD)
software tools to simulate the manufacturing and the operation of many ICs at different levels. At very low
level, the simulation tools are used to simulate the device fabrication and design. These simulation tools
are based on solving mathematical equations that describe the physics of dopant diffusion, silicon
oxidation, etching, deposition, lithography, implantation, and metallization. The simulation of physical
etching solves etching equations to calculate the etching rate. And this rate is used to move the geometry
of the device. The simulation of non-physical (geometrical) etching is based on geometrical Boolean
operations. In this paper, we are proposing new and advanced geometrical etching algorithms for the
process simulation of three dimensional (3D) micro electro mechanical systems (MEMS) and MEMStunable
vertical cavity semiconductor optical amplifiers (VCSOAs). These algorithms are based on
advanced domain decomposition methods, Delaunay meshing algorithms, and surface re-meshing and
smoothing techniques. These algorithms are simple, robust, and significantly reduce the overall run time
of the process simulation of 3D MEMS and MEMS-tunable laser devices. The description of the proposed
etching algorithms will be presented. Numerical simulation results showing the performances of these
algorithms will be given and analyzed for realistic 3D MEMS and MEMS-tunable laser devices.
Topology Optimization for Additive Manufacturing as an Enabler for Robotic Ar...piyushsingh376
The current research is intended to minimize the mass of T shaped joint by using lattice structure and topological optimization tool.
The stresses, deformation, safety factor of generic and optimized design is evaluated on the basis of these mentioned parameters. The findings have shown that topological optimization method is best as compared to lattice structure method for weight minimization.
Advanced Algorithms for Etching Simulation of 3d Mems-Tunable Lasers ijctcm
This The integrated circuits (ICs) industry uses a number of technology computer aided design (TCAD) software tools to simulate the manufacturing and the operation of many ICs at different levels. At very low level, the simulation tools are used to simulate the device fabrication and design. These simulation tools are based on solving mathematical equations that describe the physics of dopant diffusion, silicon oxidation, etching, deposition, lithography, implantation, and metallization. The simulation of physical etching solves etching equations to calculate the etching rate. And this rate is used to move the geometry of the device. The simulation of non-physical (geometrical) etching is based on geometrical Boolean operations. In this paper, we are proposing new and advanced geometrical etching algorithms for the process simulation of three dimensional (3D) micro electro mechanical systems (MEMS) and MEMStunable vertical cavity semiconductor optical amplifiers (VCSOAs). These algorithms are based on advanced domain decomposition methods, Delaunay meshing algorithms, and surface re-meshing and smoothing techniques. These algorithms are simple, robust, and significantly reduce the overall run time of the process simulation of 3D MEMS and MEMS-tunable laser devices. The description of the proposed etching algorithms will be presented. Numerical simulation results showing the performances of these algorithms will be given and analyzed for realistic 3D MEMS and MEMS-tunable laser devices.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Many Machine Learning inference workloads compute predictions based on a limited number of models that are deployed together in the system. These models often share common structure and state. This scenario provides large rooms for optimizations of runtime and memory, which current systems fall short in exploring because they employ a black-box model of ML models and tasks, thus being unaware of optimization and sharing opportunities.
On the opposite side, Pretzel adopts a white-box description of ML models, which allows the framework to perform optimizations over deployed models and running tasks, saving memory and increasing the overall system performance. In this talk we will show the motivations behind Pretzel, its current design and possible future developments.
Optimization of Design Parameters for Crane Hook Using Finite Element AnalysisIJRTEMJOURNAL
The Crane hooks are very at risk segments that are regularly utilized for mechanical purposes.
In this way such segments in an industry must be produced and composed in an approach to convey most extreme
execution without failure. Failure of a crane hook essentially relies upon three central point i.e. measurement,
material, overload. The undertaking is worried towards expanding the safe load by fluctuating the cross-sectional
measurements of the four distinct segments and diverse materials. The chose areas are square, circle, and
trapezoidal. The territory stays consistent while changing the measurements of the four unique segments. The
crane hook is demonstrated utilizing catia programming. The pressure and life investigation is finished utilizing
ANSYS 18.1 workbench. The ordinary worry along add up to misshaping, stress and life’s according to the
materials considered. It is discovered that trapezoidal cross segment yields most extreme load of 4000 KG to 5000
KG for steady cross segment zone among four cross segment.
Finite element analysis of center pin and bracket of jig fixture assembly ijm...Dr.Vikas Deulgaonkar
The manufacturing industry caters the range of products to satisfy the ever changing market needs.
To overcome the increasing production demands, the industry implies various techniques. We need a technique for
increasing the production of drilling two holes on a Railway Pinion, improve the quality of product and reduce the
operation time. This project aims to design the Jig and Fixture for the same. The 3-dimensional Computer Aided Model
of the components is made using CATIA V5-R21 software. To study the behavior of component, simulation is carried out.
Preprocessing of the CAD model is carried in Hypermesh software. Boundary conditions are applied using physical
situations of the components. Finite element analysis of the components is done, and the results obtained are compared
with the theoretical analysis and also with the available literature. The stresses and deformations are found within desired limits. Using FE analysis, the parts are manufactured and assembled.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
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modeling and efficiency in calculation.
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Application of local search methods for solving a quadratic assignment problem: A case study
1. 1
Ertek, G., Aksu, B., Birbil, S. E., İkikat, M. C., Yıldırmaz, C (2005). "Application of local search
methods for solving a quadratic assignment problem: A case study", Proceedings of Computers and
Industrial Engineering Conference, 2005
Note: This is the final draft version of this paper. Please cite this paper (or this final draft) as
above. You can download this final draft from http://research.sabanciuniv.edu.
APPLICATION OF LOCAL SEARCH METHODS FOR SOLVING
A QUADRATIC ASSIGNMENT PROBLEM: A CASE STUDY
Gürdal Ertek, Burak Aksu, Ş. İlker Birbil, Murat Cihan İkikat, Can Yıldırmaz
Sabancı University
Orhanlı, Tuzla 34956
Istanbul, Turkey
2. 2
Abstract:
This paper discusses the design and application of local search methods to a real-life
application at a steel cord manufacturing plant. The case study involves a layout
problem that can be represented as a Quadratic Assignment Problem (QAP). Due to the
nature of the manufacturing process, certain machinery need to be allocated in close
proximity to each other. This issue is incorporated into the objective function through
assigning high penalty costs to the unfavorable allocations. QAP belongs to one of the
most difficult class of combinatorial optimization problems, and is not solvable to
optimality as the number of facilities increases. We implement the well-known local
search methods, 2-opt, 3-opt and tabu search. We compare the solution performances
of the methods to the results obtained from the NEOS server, which provides free
access to many optimization solvers on the internet.
Keywords:
quadratic assignment problem, steel cord manufacturing, local search methods, tabu
search, NEOS online server
Introduction
This paper discusses local search heuristics applied to a real-world problem from industry. The
problem is the determination of the layout of a steel-cord manufacturing factory. Steel cord is
typically used as the main reinforcement material in manufacturing steel radial tires. It strengthens
the tire to provide fuel savings, long mileage, safety and comfort. The steel cord manufacturing goes
through continuous processes, where wire semi-products are stored on discrete inventory units,
namely “spools” (see Figure 1). The literature on steel cord manufacturing is not extensive, since this
is a very specialized type of manufacturing, and the systems required are produced and installed by
only a handful of companies in the world. We refer the interested readers to the following three
studies: Thomas et al. (2002) report improvement of operations in a steel cord manufacturing
company using simulation. Mercankaya (2003) develops an optimization-based decision support
system for steel cord manufacturing. Türkseven and Ertek (2003) explain how the quality and the
productivity were improved in steel cord manufacturing through custom-built simulation software.
3. 3
Their objective is to determine the optimal spool lengths under certain constraints on the spool
lengths.
Figure 1. Spool on which wire is wound
In steel cord manufacturing incoming raw material, the “steel rod wire”, is thinned by dry and wet
drawing into “filaments” that are used in successive bunching operations to construct the “steel cord”
final products (see Figure 2). The focus of our research is the second phase of production, which starts
with wet wire drawing and ends with spiraling. The first phase of the production is carried out by
machines that are fixed to their locations. The chances of moving these machines are next to none,
since considerable time and resources would be required to make such movements. The second phase
of production, on the other hand, is carried out by machines that can be relocated. The only important
issue with the second phase of production is that certain machinery, which we refer to as machine
types MT01, MT02 and MT03, have to be located in the neighborhood of a lubricant pool. These
machines carry out wet drawing of steel cord, and use the lubricant liquid, which is supplied to the
machines by an underground pipeline system. We reflected this location constraint in the
mathematical model that we developed by assigning a high flow volume between these machine types
and the lubricant cells.
4. 4
Figure 2. Production processes in steel cord manufacturing
The Mathematical Model
We assume that the flow from an area of machine type i to another area of machine type j is equally
distributed (see Figure 3). Notice that this is a simplification of the actual process because after the
machines are assigned to the locations, one would send as much flow as possible from a type i
machine to the closest type j machine. We elaborate this issue in the summary and future research
section.
5. 5
Figure 3. Equal distribution of flow from an area of machine type i to another area of machine type j
In the subsequent discussion, the acronyms LBR and WH stand for the lubricant pool and the
warehouse, respectively. Before we give the mathematical model, let us define the sets, the parameters
and the decision variables.
Sets
M: the set of machine types, M = {MT01, MT02, …, MT12, LBR, WH}
A: the set of areas, A = {1, 2, …, 69}
Parameters
6. 6
Fij: the total flow from an area dedicated to machine type i to an area dedicated to machine type j;
i, j M
Dkl: the rectilinear distance between area k and l; k, l A
Ki: the number of areas assigned to machine type i
Decision variables
xik = 1 if area k is assigned to machine type i; 0 otherwise.
The overall mathematical model then becomes
min Mi Ak Mj Al
jlikklij xxDF
s.t. ,i
Ak
ik Kx
Mi (1)
Mi
ikx ,1 Ak (2)
,1ikx }6,,2,1,LBR:),{(),( kikiki (3)
,1ikx }69,64,59,54,49,WH:),{(),( kikiki (4)
binaryikx .and AkMi (5)
The constraint set (1) ensures that the number of areas allocated to each machine type is equal to Ki;
the required number of areas for that machine type. The constraint set (2) ensures that each area is
assigned to exactly one machine type. To fix the areas assigned to the lubricant and to the warehouse,
we introduce the constraint sets (3) and (4), respectively. The last set of constraints, (5) states that the
decision variables xik should be binary.
7. 7
As we mentioned above, to locate the machine types MT01, MT02 and MT03 close to the lubricant
pool, we have assigned a large flow value between these machine types and the lubricant pool. We also
assigned high values for flows from machines that directly feed into the warehouse (namely, machines
MT04, MT06, MT07, MT11, MT12). Clearly, assigning unnecessarily large values for specific flows
creates sudden jumps in the objective function values. Therefore, a special care should be taken to set
this value. In our study, we have used the following calculation
FFF jiij for },MT03MT02,MT01,{andLBR ji
FFF jiij for },MT12MT11,MT07,MT06,MT04,{andWH ji
where
.},{ },{
WHLBRMi WHLBRMj ijFF
The presented mathematical model is very similar to the Quadratic Assignment Problem (QAP)
problem. Thus, some of the solution methods developed for QAP can be applied to solve the presented
problem after minor modifications. Among these solution methods, local search heuristics such; as
swapping, tabu search, and so on, are frequently used because these methods are relatively easy to
implement. Moreover, due to the moderate size of the presented problem, standard solvers may also
provide a solution. This is particularly important for practitioners, who prefer to use software
packages rather than creating their own tools. We next present our efforts to solve the problem with
an easily accessible online solver as well as with some local search methods.
Solution Approaches
GAMS Model
The first solution approach that we applied was to build a mathematical model using the GAMS
software (http://www.gams.com). Since the model required specification of the rectilinear distances
8. 8
between areas we had to implement a “model generator” program to generate the model
automatically based on input data. This implementation was carried out using the Java programming
language. The model generator reads in the machine types, the number of areas assigned to each
machine type (Ki), and the flows from each area of machine type i to each area of machine type j (i, j
M). The model generator then generates the GAMS model file which is submitted to NEOS server
which provides free access to many optimization solvers on the internet (http://www-
neos.mcs.anl.gov/neos/).
We used the submit client (written in Java) to submit the GAMS model to NEOS server. While
submitting we selected the Solvers menu, the menu item “Mixed Integer Nonlinearly Constrained
Optimization”, and finally the menu item “SBB [GAMS Input]”.
The solution found by the online solver has objective function value of 6,953,483 and is given in
Figure 4. The visualization is done by a Java program. In this solution MT01, MT02, and MT03 are
assigned to areas close to the lubricant (LBR).
2-opt and 3-opt
We implemented 2-opt and 3-opt algorithms for the problem again using Java. The 2-opt algorithm
performs an exchange among the machine types of two areas, and keeps the solution if the objective
function (OF) value has improved (decreased). 3-opt performs an exchange among machine types of
three areas, and keeps the solution if the OF value has improved (decreased).
We fed the solution in Figure 4 as the starting solution for both 2-opt and 3-opt. The algorithms
terminated without finding any improved solutions.
Tabu search
Finally we employed the well-known tabu search heuristic developed by Taillard (1991) to our
problem. The C++ code for the heuristic is available at the following address:
http://ina.eivd.ch/collaborateurs/etd/. Since the objective function value in our problem has to
involve the additional costs resulting from the large flows to the lubricant cells, we have slightly
modified the algorithm proposed by Taillard (1991). We selected 5 different starting solutions, and
9. 9
observed that all these solutions had the objective function value of 6,953,483, which is identical to
the objective function value found by NEOS server. This shows that tabu search heuristic is very much
applicable for the problem that we have presented.
Figure 4. The layout suggested by both NEOS and local search heuristics
Summary and Future Research
We have presented a slightly-modified QAP model and discussed the solution approaches that we
employed to solve the model. For our problem, where the real-world data came from a steel cord
manufacturer, the solution (in Figure 4) suggested by a well-known tabu search heuristic was the
same as the solution found by the NEOS server. We have also observed that 2-opt and 3-opt heuristics
could not improve on this solution. This solution thus can be considered a pseudo-optimal solution.
There is an interesting research problem that can be defined based on the problem described here. In
the problem that we presented we have assumed that the flow from each area of machine type i to
each area of machine type i is equal. There is no guarantee that this is the best policy. Indeed, the
decision of how to assign the flows from each area of machine type i to each area of machine type j is
10. 10
an embedded network flow problem. For example, the optimal flows for the system in Figure 3 can be
as given in Figure 5. Given a layout, each flow assignment is a possible solution, and given a flow
assignment each layout choice is a possible solution. Thus, there is a need to develop algorithms that
can solve these two interrelated problems simultaneously. Birbil et al. (2005) discuss this problem.
Figure 5. A possible assignment of flows between areas of two machine types
References
Birbil, Ş. İ., Ertek, G., Frenk, J. B. G., Still, G., & Zhang, S. (2005). Simultaneous solution of
assignment and network flow problems. Working paper. Istanbul, Turkey: Sabancı University.
Mercankaya, B. (2003). Sales forecasting and production planning of BEKSA in the context of supply
chain management. LFI report. Istanbul, Turkey: Sabancı University.
11. 11
Taillard, E. (1991). Robust taboo search for the QAP. Parallel Computing, 17, 443-455.
Thomas, J., Todi, J., & Paranjpe, A. (2002). Optimization of operations in a steel wire manufacturing
company. In E. Yücesan, C. H. Chen, J. L. Snowdon, and J. M. Charnes: Proceedings of 2002
Winter Simulation Conference (pp. 1151-1156). Piscataway, New Jersey: Institute of Electrical and
Electronics Engineers.
Türkseven, C. H., & Ertek, G. (2003). Simulation modeling for quality and productivity in steel-cord
manufacturing. In S. Chick, P. J. Sanchez, D. Ferrin, & D. J. Morrice: Proceedings of 2003 Winter
Simulation Conference (pp. 1225-1229). Piscataway, New Jersey: Institute of Electrical and
Electronics Engineers.