This paper reports work motivated by a real world assortment problem in packaging industry. A novel network flow model has been developed to solve the problem of selecting the optimal set of roll types for use in production. The model can incorporate fixed costs that depend on the number of elements in the assortment as well as the selected roll types. While the trade-off between inventory cost and cost of waste is resolved optimally through the model, graphical understanding of the trade-off can bring insights into the decision making process.
This graphical analysis has been demonstrated on a computational example.
http://research.sabanciuniv.edu.
A genetic algorithm approach for multi objective optimization of supply chain...Phuong Dx
This document summarizes a research paper that proposes using a genetic algorithm to solve a multi-objective supply chain network design problem. The objectives are to minimize total costs, maximize customer service levels, and maximize balanced capacity utilization across distribution centers. An experiment is conducted using real company data to evaluate the performance of the genetic algorithm and compare it to multi-objective simulated annealing. The genetic algorithm is able to generate a set of Pareto-optimal solutions for the decision maker to evaluate tradeoffs between multiple conflicting objectives in supply chain network design.
Supply chain design under uncertainty using sample average approximation and ...SSA KPI
This document summarizes a study on supply chain design under uncertainty. The authors present a two-stage stochastic programming model of a supply chain consisting of splitting and combining production processes. The first stage involves strategic decisions about facility locations and capacities. The second stage models operational decisions over multiple time periods to satisfy uncertain demand. Short-term demand uncertainty is modeled using forecasting and scenario generation methods. The authors solve the problem using sample average approximation combined with dual decomposition and present computational results for different sample sizes and levels of data aggregation in the second stage.
Implementation and Validation of Supplier Selection Model for Planner Machine...IJSRD
Supplier selection is the process through which firms identify, evaluate, and contract with suppliers. The supplier selection process deploys a tremendous amount of a firm’s financial resources. In return, manufacturing industries expect important benefits from contracting with suppliers offering high value. Like many complex supply chain problems, vendor selection problems are not so well defined which can be handed over completely to computers, whereas many human characteristics are also essential to the issues. In this paper attention is given to the fuzzy System helps Vendor Selection Problem (VSP) for Radial Drilling Bed (RDB). It required expert’s view, conversion it into fuzzy term, making 8 rule base Model with implementing Fuzzy System using MATLAB. At ending point, conclusions and likely areas of Fuzzy in selecting vendors are present.
Modelling of Vendor Selection Problem for Conventional Lathe Machine Bed by F...IJSRD
Like many complex supply chain problems, vendor selection problems are not so well defined which can be handed over completely to computers, whereas many human characteristics are also essential to the issues. In this paper attention is given to the fuzzy System helps Vendor Selection Problem (VSP) for Conventional Lathe Machine Bed . It required expert’s view, conversion it into fuzzy term, making 8 rule base Model with implementing Fuzzy System using MATLAB. At ending point, conclusions and likely areas of Fuzzy in selecting vendors are present.
Supplier Selection and Evaluation by Fuzzy-AHP Extent Analysis: A Case Study ...Dr. Amarjeet Singh
The ready-made garments (RMG)is a rapid
growing industry in Bangladesh and contributing
significantly in the country’s economy. Effective supplier
selection policy has significant strategic importance in the
performance of such fast moving consumer goods industry.
The supplier selection process is essentially a multi-criterion
decision making problem which, therefore, must be
developed systematically. Many models have been developed
and proposed to find optimum solutions of this complex
decision-making problem. Fuzzy Analytic Hierarchy
Process (Fuzzy-AHP), which is a derived extension of
classical Analytical Hierarchy Process (AHP),is an excellent
method for deciding among the complex structure at
different levels. In this paper an extent analysis of FuzzyAHP has been applied to evaluate and select the best
supplier agency providing most satisfaction. The evaluation
criteria are developed particularly for an RMG
manufacturer in Bangladesh context and used successfully
in the proposed model. A detailed implementation process is
presented in this paper and finally the best supplier agency
has been proposed from the outcome of the model.
This document describes a finite element method for modeling complex 3D crack propagation in quasi-brittle materials like concrete. The method embeds cohesive elements between solid elements in initial finite element meshes to model potential cracks. Neither remeshing nor predefined crack paths are required. The method was implemented in ABAQUS and used to model crack propagation in four concrete structure examples, showing good agreement with tests or other simulations. The method offers engineers an efficient tool for 3D fracture modeling using a commercial finite element package.
SIMULATION-BASED OPTIMIZATION USING SIMULATED ANNEALING FOR OPTIMAL EQUIPMENT...Sudhendu Rai
The paper describes a software toolkit that enables the data-driven simulation-based optimization of print shops It enables quick modeling of complex print production environments under the cellular production framework. The software toolkit automates several steps of the modeling process by taking declarative inputs from the end-user and then automatically generating complex simulation models that are used to determine improved design and operating points. This paper describes the addition of another layer of automation consisting of simulation-based optimization using simulated-annealing that enables automated search of a large number of design alternatives in the presence of operational constraints to determine a cost-optimal solution. The results of the application of this approach to a real-world problem are also described.
AN INTEGRATED APPROACH FOR ENHANCING READY MIXED CONCRETE SELECTION USING TEC...A Makwana
The use of Ready Mixed Concrete (RMC) by the construction industry in most industrialized
countries is now well established. With the help of going over expertise of experts and their relevant
specialized literature, effective Criterias in Ready Mixed Concrete (RMC) selection and the Criterias
which will be used in their evaluation is extracted. For TOPSIS, the computations were carried out
using Microsoft Excel 2013. The weight of the Criterias is calculated first through Analytic
Hierarchy Process (AHP) and then it is analyzed by Technique for Order Preference by Similarity to
Ideal Solution (TOPSIS) method. The respondents were selected from various construction
occupancy mainly Ready Mixed Concrete (RMC) Plant Managers, Consultants and Contractors.
Total 100 Survey Questionnaires were distributed to Respondents in Anand, Nadiad, Vadodara,
Ahmedabad, from which 60 Responses were collected as per sample size calculation, in that 21 were
from Ready Mixed Concrete (RMC) Plant Managers, 26 were from consultants and 13 were from
contractors.The problem solution result shows: Respondent no. 3 (R3) is best because of its largest
weight age and Respondent no. 25 (R25) is worse because of its smallest weightage.
A genetic algorithm approach for multi objective optimization of supply chain...Phuong Dx
This document summarizes a research paper that proposes using a genetic algorithm to solve a multi-objective supply chain network design problem. The objectives are to minimize total costs, maximize customer service levels, and maximize balanced capacity utilization across distribution centers. An experiment is conducted using real company data to evaluate the performance of the genetic algorithm and compare it to multi-objective simulated annealing. The genetic algorithm is able to generate a set of Pareto-optimal solutions for the decision maker to evaluate tradeoffs between multiple conflicting objectives in supply chain network design.
Supply chain design under uncertainty using sample average approximation and ...SSA KPI
This document summarizes a study on supply chain design under uncertainty. The authors present a two-stage stochastic programming model of a supply chain consisting of splitting and combining production processes. The first stage involves strategic decisions about facility locations and capacities. The second stage models operational decisions over multiple time periods to satisfy uncertain demand. Short-term demand uncertainty is modeled using forecasting and scenario generation methods. The authors solve the problem using sample average approximation combined with dual decomposition and present computational results for different sample sizes and levels of data aggregation in the second stage.
Implementation and Validation of Supplier Selection Model for Planner Machine...IJSRD
Supplier selection is the process through which firms identify, evaluate, and contract with suppliers. The supplier selection process deploys a tremendous amount of a firm’s financial resources. In return, manufacturing industries expect important benefits from contracting with suppliers offering high value. Like many complex supply chain problems, vendor selection problems are not so well defined which can be handed over completely to computers, whereas many human characteristics are also essential to the issues. In this paper attention is given to the fuzzy System helps Vendor Selection Problem (VSP) for Radial Drilling Bed (RDB). It required expert’s view, conversion it into fuzzy term, making 8 rule base Model with implementing Fuzzy System using MATLAB. At ending point, conclusions and likely areas of Fuzzy in selecting vendors are present.
Modelling of Vendor Selection Problem for Conventional Lathe Machine Bed by F...IJSRD
Like many complex supply chain problems, vendor selection problems are not so well defined which can be handed over completely to computers, whereas many human characteristics are also essential to the issues. In this paper attention is given to the fuzzy System helps Vendor Selection Problem (VSP) for Conventional Lathe Machine Bed . It required expert’s view, conversion it into fuzzy term, making 8 rule base Model with implementing Fuzzy System using MATLAB. At ending point, conclusions and likely areas of Fuzzy in selecting vendors are present.
Supplier Selection and Evaluation by Fuzzy-AHP Extent Analysis: A Case Study ...Dr. Amarjeet Singh
The ready-made garments (RMG)is a rapid
growing industry in Bangladesh and contributing
significantly in the country’s economy. Effective supplier
selection policy has significant strategic importance in the
performance of such fast moving consumer goods industry.
The supplier selection process is essentially a multi-criterion
decision making problem which, therefore, must be
developed systematically. Many models have been developed
and proposed to find optimum solutions of this complex
decision-making problem. Fuzzy Analytic Hierarchy
Process (Fuzzy-AHP), which is a derived extension of
classical Analytical Hierarchy Process (AHP),is an excellent
method for deciding among the complex structure at
different levels. In this paper an extent analysis of FuzzyAHP has been applied to evaluate and select the best
supplier agency providing most satisfaction. The evaluation
criteria are developed particularly for an RMG
manufacturer in Bangladesh context and used successfully
in the proposed model. A detailed implementation process is
presented in this paper and finally the best supplier agency
has been proposed from the outcome of the model.
This document describes a finite element method for modeling complex 3D crack propagation in quasi-brittle materials like concrete. The method embeds cohesive elements between solid elements in initial finite element meshes to model potential cracks. Neither remeshing nor predefined crack paths are required. The method was implemented in ABAQUS and used to model crack propagation in four concrete structure examples, showing good agreement with tests or other simulations. The method offers engineers an efficient tool for 3D fracture modeling using a commercial finite element package.
SIMULATION-BASED OPTIMIZATION USING SIMULATED ANNEALING FOR OPTIMAL EQUIPMENT...Sudhendu Rai
The paper describes a software toolkit that enables the data-driven simulation-based optimization of print shops It enables quick modeling of complex print production environments under the cellular production framework. The software toolkit automates several steps of the modeling process by taking declarative inputs from the end-user and then automatically generating complex simulation models that are used to determine improved design and operating points. This paper describes the addition of another layer of automation consisting of simulation-based optimization using simulated-annealing that enables automated search of a large number of design alternatives in the presence of operational constraints to determine a cost-optimal solution. The results of the application of this approach to a real-world problem are also described.
AN INTEGRATED APPROACH FOR ENHANCING READY MIXED CONCRETE SELECTION USING TEC...A Makwana
The use of Ready Mixed Concrete (RMC) by the construction industry in most industrialized
countries is now well established. With the help of going over expertise of experts and their relevant
specialized literature, effective Criterias in Ready Mixed Concrete (RMC) selection and the Criterias
which will be used in their evaluation is extracted. For TOPSIS, the computations were carried out
using Microsoft Excel 2013. The weight of the Criterias is calculated first through Analytic
Hierarchy Process (AHP) and then it is analyzed by Technique for Order Preference by Similarity to
Ideal Solution (TOPSIS) method. The respondents were selected from various construction
occupancy mainly Ready Mixed Concrete (RMC) Plant Managers, Consultants and Contractors.
Total 100 Survey Questionnaires were distributed to Respondents in Anand, Nadiad, Vadodara,
Ahmedabad, from which 60 Responses were collected as per sample size calculation, in that 21 were
from Ready Mixed Concrete (RMC) Plant Managers, 26 were from consultants and 13 were from
contractors.The problem solution result shows: Respondent no. 3 (R3) is best because of its largest
weight age and Respondent no. 25 (R25) is worse because of its smallest weightage.
Application of local search methods for solving a quadratic assignment proble...Gurdal Ertek
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.
Optimizing waste collection in an organized industrial region: A case studyGurdal Ertek
In this paper we present a case study which involves the design of a supply chain network for industrial waste collection. The problem is to transport metal waste from 17 factories to containers and from containers to a disposal center (DC) at an
organized region of automobile parts suppliers. We applied the classic mixedinteger programming (MIP) model for the two-stage supply chain to the solution of this problem. The visualization of the optimal solution provided us with several
interesting insights that would not be easily discovered otherwise.
http://research.sabanciuniv.edu.
Graphs and networks can be used to minimize project and product costs by determining the critical path and activities. The critical path method (CPM) identifies the longest path of activities in a project network to determine which activities are critical and cannot be delayed without extending the project duration. CPM is used to calculate the earliest and latest start times for activities. Identifying the critical path allows project managers to focus on reducing the time of critical path activities to minimize overall costs by reducing the project duration and resource needs. Network flow problems can also be modeled and solved using graphs and linear programming to determine the minimum cost of transporting products through a network from source to destinations.
Corner distance matching Technique is proposed, which find the interest of
points of every rived pieces. Any corner detector can be used window for finding where the
intensity value is change most and mark that point as a corner. Points of interest are found
and then for matching them distance between them is calculated. Distance can be matched
and based on that it can be found that which two edges are of piece are matching.
The document describes the development of an automatic roll pass design method to minimize the number of roll passes needed in metal forming. It uses artificial intelligence technologies like expert systems and a hybrid model to evaluate surface profiles. This allows modeling the search for an optimal sequence as a tree path search. The approach optimizes roll pass geometry automatically while reducing the time needed for design. It was validated by comparing to other automatic systems.
Finding similarities between structured documents as a crucial stage for gene...Alexander Decker
This document discusses methods for classifying structured documents by finding similarities between them. It describes how pre-processing steps like thresholding and size normalization are used. A key step is tilting documents based on detecting reference lines using clustering. Features are then extracted from the tilted images, like reference lines and logos, to classify documents. The proposed method calculates tilt angle based on the largest cluster of connected line pixels to properly orient documents for classification.
Extending network lifetime of wireless sensorIJCNCJournal
One critical issue in designing and managing a wireless sensor network is how to save the energy consumption
of the sensors in order to maximize network lifetime under the constraint of full coverage of the monitored
targets. In this paper, we adopt the common approach of creating disjoint sensor covers to prolong network
lifetime. The typical goal used in the literature is to maximize the number of covers without consideration of
the energy levels of the sensors. We argue that the network lifetime can be extended by maximizing the total
bottleneck energy of the created covers. We formally define the problem of maximizing the total bottleneck
energy of the covers, present for the first time an integer programming formulation of the problem, and develop
two algorithms to solve large problem instances. Extensive experimental tests show that the use of the goal of
maximizing the total bottleneck energy of the covers creates covers with substantially longer network lifetime
than the lifetime of the covers created with the goal of maximizing solely the number of covers.
The document proposes a new convolutional block called EffNet that aims to improve computational efficiency of convolutional neural networks while maintaining accuracy. EffNet separates the 3x3 convolution into two 1x3 and 3x1 convolutions, applies max pooling after the first convolution, and uses a less aggressive bottleneck than prior works to reduce data compression. Experiments on small image datasets show EffNet can replace convolutional layers in efficient networks without significant loss of accuracy compared to baseline and prior methods like MobileNet and ShuffleNet.
Garbage Classification Using Deep Learning TechniquesIRJET Journal
The document discusses using deep learning techniques for garbage classification. It compares the performance of different models, including support vector machines with HOG features, simple convolutional neural networks (CNNs), CNNs with residual blocks, and a hybrid model combining CNN features with HOG features. The CNN models generally performed best, with the simple CNN achieving over 93% accuracy on test data. Residual blocks did not significantly improve performance over simple CNNs. Combining CNN and HOG features was also considered but did not clearly outperform CNNs alone. Overall, CNN models were shown to effectively classify garbage using these image datasets.
1.Critically assess the aerodynamic characteristics of a vehicle.
2.Select and specify the most appropriate methods for wind tunnel testing of scale models and interpret the results of the test.
3.Analyse and critically evaluate the aerodynamic cooling systems.
M ESH S IMPLIFICATION V IA A V OLUME C OST M EASUREijcga
We develop a polygonal mesh simplification algorithm based on a novel analysis of the mesh
geometry.
Particularly, we propose first a characterization of vertices as hyperbolic or non
-
hyperbolic depend
-
ing
upon their discrete local geometry. Subsequently, the simplification process computes a volume cost for
each non
-
hyperbolic vertex, in anal
-
ogy with spherical volume, to capture the loss of fidelity if that vertex
is decimated. Vertices of least volume cost are then successively deleted and the resulting holes re
-
triangulated using a method based on a novel heuristic. Preliminary experiments i
ndicate a performance
comparable to that of the best known mesh simplification algorithms
This document discusses connector models and their accuracy. It begins by describing the evolution of connector models from simple lumped element models to complex multiport microwave models as data rates and simulation capabilities increased. The document then examines extracting connector models from both simulation and measurement, noting sources of variation. Simulation factors like mesh density, material properties, and port setup that impact model accuracy are evaluated. Measurement challenges like fixture removal calibration assumptions and footprint differences that can introduce errors are also discussed. The impacts of real world mechanical variations like insertion depth and solder variations that are often ignored are highlighted. Overall, the document aims to analyze the accuracy of connector models and highlight sources of potential inaccuracies.
Optimizing Waste Collection In An Organized Industrial Region: A Case Studyertekg
This document summarizes a case study that optimizes industrial waste collection from 17 factories located in an organized industrial region in Turkey. The authors developed a mixed integer programming model to determine the optimal waste container locations and transportation routes to minimize total costs. They applied the model to real data from an industrial zone. The optimal solution selected 3 out of 5 candidate locations and had a minimum monthly cost of 70,338 Turkish Lira. The authors also created a visualization of the optimal supply chain network to provide additional insights into the solution.
Analytical Model Of An Induction Motor Taking Into Account The Punching Proce...Ashley Carter
This document presents an analytical model for calculating the operating parameters of an induction motor that accounts for changes in the material properties of the laminated core caused by the punching process. The model determines an equivalent width and properties for a uniformly damaged zone near cut edges based on magnetic property measurements of samples with different widths. These equivalent properties are then used in an analytical circuit model to calculate motor losses and efficiency. The results show good agreement with measurements and demonstrate the importance of accounting for size-dependent material changes induced during manufacturing.
Cost optimization of pipeline systems using genetic algorithmIAEME Publication
This document summarizes a research paper that uses a genetic algorithm to optimize the cost of irrigation pipeline networks. The paper aims to find the lowest cost pipe diameter configuration that meets hydraulic constraints like head requirements. It first describes using a genetic algorithm to represent different pipe diameter combinations as chromosomes. It then calculates the cost of initial random configurations and checks if they meet constraints. The algorithm iteratively applies genetic operators like selection, crossover and mutation to chromosomes until optimized low-cost configurations are found that satisfy constraints like supplying required water flows and pressures.
Analysis of Genetic Algorithm for Effective power Delivery and with Best Upsurgeijeei-iaes
Wireless network is ready for hundreds or thousands of nodes, where each node is connected to one or sometimes more sensors. WSN sensor integrated circuits, embedded systems, networks, modems, wireless communication and dissemination of information. The sensor may be an obligation to technology and science. Recent developments underway to miniaturization and low power consumption. They act as a gateway, and prospective clients, I usually have the data on the server WSN. Other components separate routing network routers, called calculating and distributing routing tables. Discussed the routing of wireless energy balance. Optimization solutions, we have created a genetic algorithm. Before selecting an algorithm proposed for the construction of the center console. In this study, the algorithms proposed model simulated results based on "parameters depending dead nodes, the number of bits transmitted to a base station, where the number of units sent to the heads of fuel consumption compared to replay and show that the proposed algorithm has a network of a relative.
The document summarizes a study on determining the optimal disassembly sequence of a cell phone to minimize the number of workstations and idle times. Data on disassembling 25 parts of a Samsung cell phone by 3 workers was analyzed using a sequencing algorithm in operations research. The analysis found the total estimated time was 154 minutes, with idle times of 9, 15 and 13 minutes for each worker respectively. This allows placing workers to minimize idle times in a disassembly line.
A Minimum Spanning Tree Approach of Solving a Transportation Probleminventionjournals
: This work centered on the transportation problem in the shipment of cable troughs for an underground cable installation from three supply ends to four locations at a construction site where they are needed; in which case, we sought to minimize the cost of shipment. The problem was modeled into a bipartite network representation and solved using the Kruskal method of minimum spanning tree; after which the solution was confirmed with TORA Optimization software version 2.00. The result showed that the cost obtained in shipping the cable troughs under the application of the method, which was AED 2,022,000 (in the United Arab Emirate Dollar), was more effective than that obtained from mere heuristics when compared
International Journal of Engineering Research and DevelopmentIJERD Editor
This document discusses optimization and simulation of a creasing machine. It begins with an introduction to creasing machines and the creasing process for corrugated sheets. It then discusses CAD modeling and FEM analysis that was performed on the creasing rollers to identify opportunities to improve the machine. The goal is to optimize the production rate by reducing setup time for different sheet widths. In conclusion, the work focuses on using FEM testing to evaluate failures and help design an improved system with higher production rates per hour.
Design a 3D CAD Model of a Stealth Aircraft and Generate Mesh to Optimize Mes...IRJET Journal
This document describes the process of creating a 3D CAD model of a stealth aircraft, cleaning the geometry, and generating a mesh to optimize mesh quality. The authors created the CAD model, checked it for errors, and then generated both a structured and unstructured mesh. They analyzed mesh quality parameters like aspect ratio, Jacobian ratio, warpage angle, and interior angles using the pre-processing software SimLab and HyperWorks. The quality reports showed over 99.5% of elements passed the various checks, indicating an optimized mesh was generated. This high-quality mesh will provide accurate results for design analysis simulations.
Supplier and buyer driven channels in a two-stage supply chainGurdal Ertek
This summarizes a research paper that explores supplier and buyer-driven channels in a two-stage supply chain model. It develops models where either the supplier or buyer has dominant bargaining power to determine pricing. The paper shows that when the buyer has power, it is optimal for them to use only a multiplier on wholesale price and not a markup. It also shows market price and sensitivity increases with operational costs. The sensitivity of market price to wholesale price increases non-linearly and is bounded from below. Increasing costs have a decreasing marginal impact on prices and profits. There are cases where suppliers prefer buyer-driven channels and vice versa.
Simulation modeling for quality and productivity in steel cord manufacturingGurdal Ertek
We describe the application of simulation modeling to estimate and improve quality and productivity performance of a steel cord manufacturing system. We describe the typical steel
cord manufacturing plant, emphasize its distinguishing characteristics, identify various production settings and discuss applicability of simulation as a management decision support tool. Besides presenting the general structure of the developed simulation model, we focus on wire fractures, which can be an important source of system disruption.
http://research.sabanciuniv.edu.
More Related Content
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Application of local search methods for solving a quadratic assignment proble...Gurdal Ertek
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.
Optimizing waste collection in an organized industrial region: A case studyGurdal Ertek
In this paper we present a case study which involves the design of a supply chain network for industrial waste collection. The problem is to transport metal waste from 17 factories to containers and from containers to a disposal center (DC) at an
organized region of automobile parts suppliers. We applied the classic mixedinteger programming (MIP) model for the two-stage supply chain to the solution of this problem. The visualization of the optimal solution provided us with several
interesting insights that would not be easily discovered otherwise.
http://research.sabanciuniv.edu.
Graphs and networks can be used to minimize project and product costs by determining the critical path and activities. The critical path method (CPM) identifies the longest path of activities in a project network to determine which activities are critical and cannot be delayed without extending the project duration. CPM is used to calculate the earliest and latest start times for activities. Identifying the critical path allows project managers to focus on reducing the time of critical path activities to minimize overall costs by reducing the project duration and resource needs. Network flow problems can also be modeled and solved using graphs and linear programming to determine the minimum cost of transporting products through a network from source to destinations.
Corner distance matching Technique is proposed, which find the interest of
points of every rived pieces. Any corner detector can be used window for finding where the
intensity value is change most and mark that point as a corner. Points of interest are found
and then for matching them distance between them is calculated. Distance can be matched
and based on that it can be found that which two edges are of piece are matching.
The document describes the development of an automatic roll pass design method to minimize the number of roll passes needed in metal forming. It uses artificial intelligence technologies like expert systems and a hybrid model to evaluate surface profiles. This allows modeling the search for an optimal sequence as a tree path search. The approach optimizes roll pass geometry automatically while reducing the time needed for design. It was validated by comparing to other automatic systems.
Finding similarities between structured documents as a crucial stage for gene...Alexander Decker
This document discusses methods for classifying structured documents by finding similarities between them. It describes how pre-processing steps like thresholding and size normalization are used. A key step is tilting documents based on detecting reference lines using clustering. Features are then extracted from the tilted images, like reference lines and logos, to classify documents. The proposed method calculates tilt angle based on the largest cluster of connected line pixels to properly orient documents for classification.
Extending network lifetime of wireless sensorIJCNCJournal
One critical issue in designing and managing a wireless sensor network is how to save the energy consumption
of the sensors in order to maximize network lifetime under the constraint of full coverage of the monitored
targets. In this paper, we adopt the common approach of creating disjoint sensor covers to prolong network
lifetime. The typical goal used in the literature is to maximize the number of covers without consideration of
the energy levels of the sensors. We argue that the network lifetime can be extended by maximizing the total
bottleneck energy of the created covers. We formally define the problem of maximizing the total bottleneck
energy of the covers, present for the first time an integer programming formulation of the problem, and develop
two algorithms to solve large problem instances. Extensive experimental tests show that the use of the goal of
maximizing the total bottleneck energy of the covers creates covers with substantially longer network lifetime
than the lifetime of the covers created with the goal of maximizing solely the number of covers.
The document proposes a new convolutional block called EffNet that aims to improve computational efficiency of convolutional neural networks while maintaining accuracy. EffNet separates the 3x3 convolution into two 1x3 and 3x1 convolutions, applies max pooling after the first convolution, and uses a less aggressive bottleneck than prior works to reduce data compression. Experiments on small image datasets show EffNet can replace convolutional layers in efficient networks without significant loss of accuracy compared to baseline and prior methods like MobileNet and ShuffleNet.
Garbage Classification Using Deep Learning TechniquesIRJET Journal
The document discusses using deep learning techniques for garbage classification. It compares the performance of different models, including support vector machines with HOG features, simple convolutional neural networks (CNNs), CNNs with residual blocks, and a hybrid model combining CNN features with HOG features. The CNN models generally performed best, with the simple CNN achieving over 93% accuracy on test data. Residual blocks did not significantly improve performance over simple CNNs. Combining CNN and HOG features was also considered but did not clearly outperform CNNs alone. Overall, CNN models were shown to effectively classify garbage using these image datasets.
1.Critically assess the aerodynamic characteristics of a vehicle.
2.Select and specify the most appropriate methods for wind tunnel testing of scale models and interpret the results of the test.
3.Analyse and critically evaluate the aerodynamic cooling systems.
M ESH S IMPLIFICATION V IA A V OLUME C OST M EASUREijcga
We develop a polygonal mesh simplification algorithm based on a novel analysis of the mesh
geometry.
Particularly, we propose first a characterization of vertices as hyperbolic or non
-
hyperbolic depend
-
ing
upon their discrete local geometry. Subsequently, the simplification process computes a volume cost for
each non
-
hyperbolic vertex, in anal
-
ogy with spherical volume, to capture the loss of fidelity if that vertex
is decimated. Vertices of least volume cost are then successively deleted and the resulting holes re
-
triangulated using a method based on a novel heuristic. Preliminary experiments i
ndicate a performance
comparable to that of the best known mesh simplification algorithms
This document discusses connector models and their accuracy. It begins by describing the evolution of connector models from simple lumped element models to complex multiport microwave models as data rates and simulation capabilities increased. The document then examines extracting connector models from both simulation and measurement, noting sources of variation. Simulation factors like mesh density, material properties, and port setup that impact model accuracy are evaluated. Measurement challenges like fixture removal calibration assumptions and footprint differences that can introduce errors are also discussed. The impacts of real world mechanical variations like insertion depth and solder variations that are often ignored are highlighted. Overall, the document aims to analyze the accuracy of connector models and highlight sources of potential inaccuracies.
Optimizing Waste Collection In An Organized Industrial Region: A Case Studyertekg
This document summarizes a case study that optimizes industrial waste collection from 17 factories located in an organized industrial region in Turkey. The authors developed a mixed integer programming model to determine the optimal waste container locations and transportation routes to minimize total costs. They applied the model to real data from an industrial zone. The optimal solution selected 3 out of 5 candidate locations and had a minimum monthly cost of 70,338 Turkish Lira. The authors also created a visualization of the optimal supply chain network to provide additional insights into the solution.
Analytical Model Of An Induction Motor Taking Into Account The Punching Proce...Ashley Carter
This document presents an analytical model for calculating the operating parameters of an induction motor that accounts for changes in the material properties of the laminated core caused by the punching process. The model determines an equivalent width and properties for a uniformly damaged zone near cut edges based on magnetic property measurements of samples with different widths. These equivalent properties are then used in an analytical circuit model to calculate motor losses and efficiency. The results show good agreement with measurements and demonstrate the importance of accounting for size-dependent material changes induced during manufacturing.
Cost optimization of pipeline systems using genetic algorithmIAEME Publication
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A New Network Flow Model for Determining the Assortment of Roll Types in Packaging Industry
1. 1
Tombuş, O., Ertek, G., Atay, C., Kökten, G., and Tombuş, A.C. (2010) “A New Network Flow Model
for Determining theAssortment of Roll Types in Packaging Industry.” IEEE International
Conference on Systems, Man, Cybernetics. October 10-13, 2010, Istanbul, Turkey.
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.
A New Network Flow Model for Determining the
Assortment of Roll Types in Packaging Industry
Önder Tombuş
System Solutions
Department
Hitit Computer Services
Istanbul, Turkey
Gurdal Ertek, Ceren Atay,
Gizem Kökten
Faculty of Engineering and
Natural Sciences
Sabanci University
Istanbul, Turkey
Ayşe Cilacı Tombuş
Industrial Engineering
Department
Maltepe University
Istanbul, Turkey
2. Abstract— This paper reports work motivated by a real world assortment problem
in packaging industry. A novel network flow model has been developed to solve the
problem of selecting the optimal set of roll types for use in production. The model
can incorporate fixed costs that depend on the number of elements in the
assortment as well as the selected roll types. While the trade-off between inventory
cost and cost of waste is resolved optimally through the model, graphical
understanding of the trade-off can bring insights into the decision making process.
This graphical analysis has been demonstrated on a computational example.
Keywords— assortment problem, cutting stock, packaging industry, shortest path
problem, dynamic programming
I. INTRODUCTION
Inventory holding and generation of paper waste are two major cost contributors in packaging
industry, where papers are cut in various widths and lengths from paper rolls with varying widths
and lengths. Companies typically hold high variety of roll types (identified based on their widths) in
inventory for the purpose of decreasing the wasted scrap paper. A job (identified by its width and
length) is cut from the roll with the minimum width, that is wider than the width of the given job.
However, this results in higher inventory holding cost, accompanied with additional burden in
operational planning. Thus, there is a clear trade-off between the cost of waste and the cost of
inventory holding while deciding on the assortment of roll types to keep in inventory, and
analytical modeling is required for optimal decision making.
This paper contains two contributions: 1) It extends an existing network flow model [1] (pages
11-12) for the aforementioned assortment problem for enabling the incorporation of new types of
cost structures while preserving the network flow structure of the model; 2) It demonstrates how
the solutions of the developed model can be used by decision makers for deciding on the assortment
of roll types.
One of the most important issues in optimization modeling is the complexity of the solution
algorithm used to solve the problem to optimality. Network flow problems are a class of integer
programming optimization problems with a special structure. Integer programming models are NP-
hard, meaning that they grow increasingly and non-polynomially more complex in size when their
basic components, the number of variables and constraints, grow linearly. Thus, it becomes
computationally infeasible to solve such problems to optimality as the problem instances grow.
However, network flow problems are polynomially solvable, meaning that the time to solve such
problems to optimality grows as a polynomial function of the number of variables and constraints.
The paper is organized as follows: The one-dimensional cutting stock problem is described in
Section II. Related literature is summarized in Section III. The problem is modeled as a shortest
path problem in Section IV and is solved through dynamic programming. Finally, a computational
example is provided in Section V to demonstrate how the model solutions can be used for exploring
the trade-off between various decisions and deciding on the assortment of roll types.
II. THE PLANNING PROBLEM
The research described in this paper is motivated by one of the largest packaging companies in
Turkey, producing cardboard packaging for glassware products. Paper rolls are cut by guillotine
machines from the rolls with the minimum possible width that satisfy the dimensions required by
the job. Customer orders and thus the jobs to be cut in the plant show high variability, due to a
multitude of factors such as product variety, seasonality, packaging characteristics. Rolls with
different widths are kept in inventory and are used in production with the objective of minimizing
waste paper. The growing number of roll types used in production have resulted in an increase in
the amount of inventory and subsequently operational costs, including the costs of inventory
holding, warehousing space and material handling. Furthermore, there exists a limited space for
the inventory of paper rolls, which requires the resolution of the dilemma of having to incur
increased paper waste while trying to reduce the number of roll types.
3. The decision problem is selection of the most appropriate assortment of roll types, from among a
set of possible roll types. The objective is the minimization of total cost, which is composed of costs
of inventory holding and paper waste, when the number of roll types to be used is fixed and is given
as a constraint. The sets, parameters, decision variables, and the network modeling of the problem
are given in Section IV.
III. RELATED LITERATURE
A. Cutting Stock Problem
In this paper, our main aim is to determine the best assortment policy for roll types where the
inventory cost can be decreased without a significant increase in terms of the waste paper amount.
The first stream of research investigated the cutting stock problem in roll paper cutting industry
and was pioneered by the work of Gilmore and Gomory [2]. The problem considered in [2], as well
as its succeeding literature, allow for multiple cuts from the same roll, yielding a combinatorial
optimization problem. [3] notes that “the objective function, … should minimize the percentage of
waste rather than the amount of it” in the linear programming models for this problem. Restricting
the problem by limiting the minimum and maximum number of sheets per pattern, as [4] did, did
not yield efficient results to cutting stock problem due to its sequential approach. In summary, the
NP-hard nature of the classic cutting stock problem does not allow for polynomial solution times
when modeled as a linear program [5].
The cutting stock problem is polynomially solvable only if a single sheet is cut from the rolls
(one-dimensional cutting stock problem) and thus the combinatorial nature of the problem is
eliminated. Under this assumption, the problem can be treated as a network flow problem and can
be solved through a dynamic programming approach, as described in [1].
As a related study with a different focus, [6] discusses a variation of the one-dimensional cutting
stock problem where the control of defects is a major concern.
B. Case Studies in Packaging Industry
In this paper, decision making is based on two conflicting objectives, which are cost of inventory
holding and the cost of cutting loss. As mentioned by [7], cutting a roll into its final dimensions is
done according to a pattern which is determined by customer orders. This paper aims to achieve a
balance between these two costs through a network flow model and a corresponding dynamic
programming model. The only work that was encountered in the literature is [3], where the
customer service impact of inventory is incorporated into the analysis through a simulation model.
IV. NETWORK MODELING OF THE PROBLEM
Similar to [1], the problem is formulated as a shortest path problem by constructing a directed
network . Let denote the number of possible roll types and where denote the number of
selected roll types. Figure 1 demonstrates the network constructed for a problem instance with
and . While [1] constructs a single-dimensional network with nodes, we construct a two-
dimensional network with nodes and arcs. This added dimension for the set of
roll types allows the incorporation of more complicated setup costs into the problem.
4. Figure 1. Demonstration of the network model, for a problem instance with five intervals and
three roll types to be selected.
In the network model, the indices of the intervals (widths of the roll types) are placed along the
axis and the indices of the selected roll types are placed along the axis. Having a positive flow
through node means that the th selected roll type (at stage of the network) corresponds to
interval . In other words, it has a length that is equal to the upper bound of interval .
represents the target number of roll types to be selected. The condition should be satisfied,
since the roll types can be selected only from among those that are available. When , the
solution is trivial: All the candidate roll types, corresponding to each of the available intervals, are
selected.
Source and sink nodes are included in the problem formulation, with a unit flow emanating from
the source and terminating at the sink. The source node represents the initial stage in the solving of
the problem (where no roll type is yet selected) and the sink node represents the last stage (where
all the selected roll types are determined, and the assortment is completed).
Set of arcs consists of three subsets: Those that emanate from the source, those that terminate at
the sink, and those between transient nodes.
The cost of traversing an arc a is defined as and is calculated based on , the waste
generated if jobs in interval are cut from selected roll type . The calculations are detailed in this
section.
The lengths of rolls are assumed infinite and the thickness of rolls are considered as identical for
each roll type.
The mathematical notation and the shortest path model is given next:
5. A. Sets
: Set of intervals,
: Set of candidate roll types,
: Set of all jobs to be cut from the selected roll types,
: Set of jobs that fall in interval
B. Nodes
: Set of nodes in the network representation
: source node
: sink node
: set of transient nodes
:
: node that represents th selected roll type having length
C. Arcs
: Set of arcs in the network representation
: set of arcs that emanate from the source node (and terminate at transient nodes)
: set of arcs that (emanate from transient nodes and) terminate at the sink node
: set of arcs that emanate from transient nodes and terminate at the transient nodes
6. D. Decision Variables
where
condition : "jobs in intervals to are assigned to the st selected roll type”
E. Lookup Tables
: the index of the interval corresponding to the length of the th selected roll type
: Upper bound value of interval
F. Parameters and Waste & Cost Calculations
: width of th selected roll type
: width of job
: length of job
: waste generated if jobs in interval are cut from selected roll type
: fixed cost (setup and fixed inventory holding) of selecting the th roll type
: overall setup cost of having only s different rolltype at the inventory
: cost of traversing arc , which is the total waste produced by traversing that arc.
: total waste if the jobs within interval to are cut from the roll which
corresponds to the st interval
7. G. Discussion
The model in [1] can handle only as the fixed cost component. However, in most real world
situations, besides the real or perceived cost of adding roll type , there is also a cost associated with
adding yet another roll type. Since the fixed cost of adding the th roll type to the assortment is not
necessarily same as adding the th roll type (where ), the fixed cost has as an index.
Finally, another type of fixed cost can be incorporated, thanks to the two-dimensional network
flow representation of the problem that takes into account the number of selected roll types.
represents the overall setup cost of having exactly different roll types. This fixed cost can be
added to the optimal value of the objective function, and will enable a more accurate calculation of
the objective function value. Even though it will not affect the optimal solution, it will affect the
objective function value, and will be important in comparing alternative scenarios (problem
instances) with varying values of .
H. Minimum Cost Flow Model
// Minimize total cost
min
s.t.
// Flow out of the source node
// Flow into the sink node
// Flow balance
// Nonnegative decision variables
V. COMPUTATIONAL EXAMPLE
In this section we demonstrate how the model solutions can be used for exploring the trade-off
between various decisions and deciding on the assortment of roll types. For this, a hypothetical
computational example was constructed to mimic a confidential dataset from the real-world. The
dynamic programming model was coded in MATLAB to solve the shortest path model for multiple
values of (number of selected roll types) and the results were plotted.
A. Problem Instance
The problem instance consists of 207 jobs, ranging from 590 to 1390 millimeters in width and
from 600 to 1386 meters in length. The set of candidate roll types were assumed to consist of 10
elements, with the widths being uniformly distributed. Since the main goal of this section is to
8. demonstrate how computational results can be used in decision making, fixed costs were assumed
to be zero to simplify computations.
B. Waste vs. Number of Selected Roll Types
“How does the generated waste change depending on the number of selected roll types?”
Figure 2 answers this question graphically for the constructed example. Since the fixed costs
were all assumed to be zero, the total cost monotonically decreases as the number of selected
roll types increases. From the figure, a decision maker can quantitatively observe the trade-off
between and .
Figure 2. Total waste (m2) for the computational example, depending on the number of
selected roll types.
C. Optimal Selection of Roll Types for Different Number of Selected Roll Types
“How does the assortment change depending on the number of selected roll
types?”
Figure 3 answers this question. This second type of analysis involves the observation of the
specific roll types that are selected, for different values of Each path in the figure corresponds to
a specific value of and the circles on the paths correspond to the widths of the selected rolls. This
type of graphical analysis shows which roll types consistently appear in the assortment. For
example, in Figure 3, certain roll widths appear again and again after a certain value of
9. Figure 3. Optimal roll widths for the computational example, depending on the number of
selected roll types.
VI. CONCLUSION AND FUTURE WORK
This paper reported work on a one-dimensional cutting stock problem in cardboard packaging.
A novel network flow model has been developed to solve the problem and setup costs that depend
on the number of elements in the assortment can be incorporated through the new model.
Graphical demonstration of the trade-off between inventory cost and cost of waste has been
demonstrated on a computational example.
ACKNOWLEDGMENT
The authors thank Sabancı University alumni Halide Ezgi Özbağ for bringing the problem into
the attention of the authors.
REFERENCES
[1] R. K. Ahuja, T. L. Magnanti, and J. B. Orlin, Network Flows: Theory, Algorithms, and Applications, Prentice-Hall,
1993.
[2] P. C. Gilmore, and R. E. Gomory, “A Linear Programming Approach to the Cutting Stock Problem,” Operations
Research, Vol. 11, No. 6, pp. 863-888, November - December, 1963.
[3] J. H. Bookbinder, and J. K. Higginson, “Customer Service vs Trim Waste in Corrugated Box Manufacture,” The
Journal of the Operational Research Society, Vol. 37, No. 11 pp. 1061-1071, November, 1986.
[4] R. W. Haasler, “A Note on Computational Modifications to the Gilmore-Gomory Cutting Stock Algorithm,”
Operations Research, Vol. 28, No. 4 pp. 1001-1005, July - August, 1980.
[5] K. C. Poldi, and M. N. Arenales, “Heuristics for the one-dimensional cutting stock problem with limited multiple
stock lengths,” Computers & Operations Research 36, 2009.
[6] B. R. Sarker, “An Optimum Solution for One-Dimensional Slitting Problems: A Dynamic Programming
Approach,” The Journal of the Operational Research Society, Vol. 39, No. 8, pp. 749-755, August, 1988.
[7] A. W. J. Kolen, and F. C. R. Spieksma, “Solving a bi-criterion cutting stock problem with open-ended demand: a
case study,” The Journal of the Operational Research Society, Vol. 51, No. 11, pp. 238-1247, November 2000.