Iranian Journal of Optimization: 5 (2)

Open Access Article

1 - Merging DMUs Based on of the idea Inverse DEA
الهه زین الدین سعید قبادی

20.1001.1.25885723.2019.11.2.1.2

In this paper, we propose a novel method using multiple-objective programming problems to answer the following question: if among a group of decision making units (DMUs), a subset of DMUs are required to merge and form a new DMU with specific input/output levels and a p More

In this paper, we propose a novel method using multiple-objective programming problems to answer the following question: if among a group of decision making units (DMUs), a subset of DMUs are required to merge and form a new DMU with specific input/output levels and a predefined efficiency target, how much should be the outputs/inputs of the merged DMU? This question answered according to the concept of inverse DEA. Sufficient conditions are established for input/output-estimation of the merged DMU using multiple-objective programming problems. A numerical example with real data is presented to illustrate the goals of this paper. Manuscript profile

Open Access Article

2 - Organizational Sustainable Competitive Advantage using ORESTE, TRIZ, SWOT Approaches in Gray Conditions
درنا تیموری علیرضا علینژاد

20.1001.1.25885723.2019.11.2.2.3

In today world, organizations’ performance and making the sustainable competitive strength have become incrementally important for them according to the quick global evolutions. The dairy industry is one of the most important industries which has made very competi More

In today world, organizations’ performance and making the sustainable competitive strength have become incrementally important for them according to the quick global evolutions. The dairy industry is one of the most important industries which has made very competitive environment. The case study of this research is Kaleh Dairy Company as one of the active companies in dairy industries. One of the most important strategic management tool called SWOT analysis was used in this research to determine the position of Kaleh Company. IE, IFE, and EFE matrices have been used to determine the proper strategies and competitive position of the company. SWOT technique was mixed with TRIZ to remove defects and improve SWOT technique and also formulate strategies. Then, the formulated strategies were prioritized by gray ORESTE to rank strategies for lack of information and non-precision data which was resulted by experts using verbal variables. Manuscript profile

Open Access Article

3 - Improving adaptive resolution of analog to digital converters using least squares mean method
Shadan Sadigh behzadi

20.1001.1.25885723.2019.11.2.3.4

This paper presents an adaptive digital resolution improvement method for extrapolating and recursive analog-to-digital converters (ADCs). The presented adaptively enhanced ADC (AE-ADC) digitally estimates the digital equivalent of the input signal by utilizing an adapt More

This paper presents an adaptive digital resolution improvement method for extrapolating and recursive analog-to-digital converters (ADCs). The presented adaptively enhanced ADC (AE-ADC) digitally estimates the digital equivalent of the input signal by utilizing an adaptive digital filter (ADF). The least mean squares (LMS) algorithm also determines the coefficients of the ADF block. In this scheme, the input bandwidth is limited to the Nyquist-rate. This scheme has the ability of enhancing its resolution by one bit through doubling the gain of a low-quality amplifier circuit. Behavioral simulation results are also provided for a 10-bit AE-ADC to verify the usefulness of the approach. Simulation results indicate that the spurious-free dynamic range (SFDR) and signal-to-noise-and-distortion-ratio (SNDR) are 68.8 dB and 55.5 dB, respectively. Manuscript profile

Open Access Article

4 - A Method for Solving Convex Quadratic Programming Problems Based on Differential-algebraic equations
معصومه عباسی

20.1001.1.25885723.2019.11.2.4.5

In this paper, a new model based on differential-algebraic equations(DAEs) for solving convex quadratic programming(CQP) problems is proposed. It is proved that the new approach is guaranteed to generate optimal solutions for this class of optimization problems. This pa More

In this paper, a new model based on differential-algebraic equations(DAEs) for solving convex quadratic programming(CQP) problems is proposed. It is proved that the new approach is guaranteed to generate optimal solutions for this class of optimization problems. This paper also shows that the conventional interior point methods for solving (CQP) problems can be viewed as a special case of the new DAEs methods. Numerical results show the efficiency of the proposed model. Manuscript profile

Open Access Article

5 - Financial efficiency evaluation in a network with feedbacks
Zohreh Moghaddas

20.1001.1.25885723.2019.11.2.5.6

Financial efficiency evaluations in a network system, considering intermediate products, nowadays consideres great importance for managers. In the process of doing business analysis, each stage of in a network is of particular importance. In this paper, with the help of More

Financial efficiency evaluations in a network system, considering intermediate products, nowadays consideres great importance for managers. In the process of doing business analysis, each stage of in a network is of particular importance. In this paper, with the help of Data Envelopment Analysis (DEA), the performance of a network with feedbacks are considerd. In this assessment, financial efficiency is being assessed for a network with with inputs, outputs, intermediate products. As an example, the application of data from petrochemical companies is considered and implemented to a supply chain for evaluation and analysis the efficiencies. Manuscript profile

Open Access Article

6 - Eco-Efficiency Evaluation in Two-Stage Network Structure: Case Study: Cement Companies
Mirpouya Mirmozaffari

20.1001.1.25885723.2019.11.2.6.7

The cement industry, as a primary trade, plays an important role in the development of a country's organization. This industry in Iran, however, despite of profuse benefits such as high-value mines, faces many challenges. Problems such as exploitation of the production More

The cement industry, as a primary trade, plays an important role in the development of a country's organization. This industry in Iran, however, despite of profuse benefits such as high-value mines, faces many challenges. Problems such as exploitation of the production require the need for doing research into this area. The main purpose of this paper is to examine the Eco-efficiency in Iran's 22 local cement companies over 2012-2016. This paper develops a Charnes, Cooper & Rhodes input oriented (CCRIO) Data Envelopment Analysis (DEA) approach for measuring the efficiency of decision processes which can be separated into two stages. The first stage uses its specific inputs to produce outputs, which part of them are consequently considered as the inputs of the second stage. The first stage is considered as the production stage and the second stage as the pollution control stage. A novel converting two-stage to one stage model is proposed to obtain the Eco-efficiency. Consequently, Malmquist productivity index (MPI) is computed to assess productivity. Although DEA is a respected method for evaluating, it fails to extract unknown information. In this study data mining decision tree and Apriori algorithms are used to extract hidden rules, and to remove unrelated data. Manuscript profile

Open Access Article

7 - Investigating the Moderating Role of Competitive Strategies on the Impact of Supply Chain Integration on the Financial and Operational Performance (Case Study: The car manufacturing industry in IRAN
رقیه توده بهمبری منصور صوفی

20.1001.1.25885723.2019.11.2.7.8

The increase of international competition motivated most of the organizations to create useful shared mutual cooperation with supply chain partners since they understood that cooperation and collaboration of supply chain partners is the prerequisite for the increase of More

The increase of international competition motivated most of the organizations to create useful shared mutual cooperation with supply chain partners since they understood that cooperation and collaboration of supply chain partners is the prerequisite for the increase of reliability level and the decrease of risks and also the enhancement of innovative qualities and profitability of the companies in recent competitive and dynamic market. Integration of supply chain is an important strategy in creating cooperation and collaboration among different elements of supply chain, and plays a vital role in the enhancement of performance of the companies in supply chain. The objective of the present study is to investigate the effect of supply chain integration on the performance of car part manufacturing companies. Current study follows a descriptive, analytical approach in which the correlation between the variables of sample under study is investigated. This sample includes 81 company which produce car parts with a grade A of SAPCO Company. Samples were selected through census in the initial phase. However in the second phase sampling was done through improbable and judgmental sampling. In order to testify hypothesis PLS method was used. The result of this study indicates that there is a direct effect between supply chain integration and improvement of operational performance of companies under investigation. Manuscript profile

Open Access Article

8 - Shifted Chebyshev Approach for the Solution of Delay Fredholm and Volterra Integro-Differential Equations via Perturbed Galerkin Method
Kazeem Issa Jafar Biazar Babatunde Yisa

20.1001.1.25885723.2019.11.2.8.9

The main idea proposed in this paper is the perturbed shifted Chebyshev Galerkin method for the solutions of delay Fredholm and Volterra integrodiﬀerential equations. The application of the proposed method is also extended to the solutions of integro-diﬀerential diﬀeren More

The main idea proposed in this paper is the perturbed shifted Chebyshev Galerkin method for the solutions of delay Fredholm and Volterra integrodiﬀerential equations. The application of the proposed method is also extended to the solutions of integro-diﬀerential diﬀerence equations. The method is validated using some selected problems from the literature. In all the problems that are considered, the new proposed approach performs better than many other methods. Manuscript profile

Open Access Article

9 - An ANP and MULTIMOORA-Based SWOT Analysis for Strategy Formulation
سهیلا مظلوم واجاری ایروان مسعودی اصل کامران حاجی نبی لیلا ریاحی

20.1001.1.25885723.2019.11.2.9.0

Since no organization can have unlimited resources, strategists should decide on a strategy that can provide the greatest benefits to the organization. Decisions on strategy formulation commit the organization to produce specific products, work in specific markets, and More

Since no organization can have unlimited resources, strategists should decide on a strategy that can provide the greatest benefits to the organization. Decisions on strategy formulation commit the organization to produce specific products, work in specific markets, and exploit certain resources and technologies for a relatively long time. Strategies dictate the long-term competitive advantages of an organization. Either good or bad, strategic decisions have multifaceted results and long-lasting consequences for organizations. So, organizations should adopt optimal strategies to move in the right direction and avoid irreparable losses. This planning calls for an optimal model of strategy formulation so that the strategists of organizations can formulate a strategy for their respected organizations readily and accurately. The present study presents a composite approach to organizational strategy formulation. Manuscript profile

Open Access Article

10 - Flying Squirrel Optimizer (FSO): A novel SI-based optimization algorithm for engineering problems
غلامرضا عزیزیان فرید میارنعیمی محسن راشکی ناصر شابختی

20.1001.1.25885723.2019.11.2.10.1

This paper provides a novel meta-heuristic optimization algorithm. The behaviors of flying squirrels in the nature are the main inspiration of this research. These behaviors include flying from tree to tree and walking on the ground or on a tree branch to find food. The More

This paper provides a novel meta-heuristic optimization algorithm. The behaviors of flying squirrels in the nature are the main inspiration of this research. These behaviors include flying from tree to tree and walking on the ground or on a tree branch to find food. They also contact each other with chirp or squeak. This algorithm is named flying squirrel optimizer (FSO). Two main theories of motion were used for the simulation of flying and walking of the flying squirrels and they are Lévy flight and normal random walk. FSO is also benchmarked on twelve mathematical functions and the answers are compared with MFO, PSO, GSA, BA, FPA, SMS, and FA. The results show that FSO can provide good results when compared with these well-known meta-heuristics approaches. Five classical engineering problems and a real issue in the field of dam engineering were employed to challenge the FSO abilities in solving engineering design problems. The results also show that the proposed FSO algorithm can be used on a wide range of problems with unknown search spaces. Manuscript profile

Open Access Article

11 - Optimal Design of Open Channel Sections Using PSO Algorithm
محسن منادی میرعلی محمدی Hamed Taghizadeh

20.1001.1.25885723.2019.11.2.11.2

This paper applies an evolutionary algorithm, the particle swarm optimization (PSO), to design the optimum open channel section. Depth, channel side slope and bottom width are considered as the variables for rectangular, triangular and trapezoidal channels, respectively More

This paper applies an evolutionary algorithm, the particle swarm optimization (PSO), to design the optimum open channel section. Depth, channel side slope and bottom width are considered as the variables for rectangular, triangular and trapezoidal channels, respectively. The objective function is minimizing the construction cost of the channel section. MATLAB software is used for programming and doing the optimization process. Manning’s uniform flow formula has been used as a constraint for the optimization model. The cost function is included the cost of earthwork, the increment in the cost of earthwork with the depth below the ground surface and the cost of lining. Simple functions of unit cost terms have been used to express the optimum values of section variables. The optimum section variables are obtained for the case of minimum area or minimum wetted perimeter problems. The results of this study showed that the PSO is a robust algorithm to compute the optimum section variables in open channel design. Manuscript profile

Open Access Article

12 - Using Theory of Constraints in Production Management and Scheduling (A Case Study)
Ahmad Hooshmand Ali Reza Mehrazeen Ali Reza Davoody Mohamad Reza Shorvarzi

20.1001.1.25885723.2019.11.2.12.3

In manufacturing institutes the only access way to maximum profit is identifying the production mix of the products based on the limitations such as policies and politics, demand and production processes. This study identifies the constraints of a tile-manufacturing com More

In manufacturing institutes the only access way to maximum profit is identifying the production mix of the products based on the limitations such as policies and politics, demand and production processes. This study identifies the constraints of a tile-manufacturing company including constraints in its production and demand line using LINGO software version 15, and identifying production bottleneck, i.e. furnace, production scheduling was provided and sensitivity analysis was con-ducted on the variables and right hand items. Positive shadow price of furnace shows efficiency of every unit on throughput. Also, in demand constraint, negative shadow price of product 16 shows decreasing effect of increase of every unit on throughput. Allowable increase and decrease of right hand items show allowable increase in furnace section and limitlessness of allowable decrease of product 16. Changes in this range causes that the current basis remains optimal changes in which causes changes in the optimal value of the target function regarding shadow prices. Manuscript profile

Open Access Article

13 - Stochastic Facility Layout Planning Problem: A Metaheuristic and Case Study
Nima Moradi

20.1001.1.25885723.2019.11.2.13.4

Facility layout is one of the most important Operations Management problems due to its direct impact on the financial performance of both private and public firms. Facility layout problem (FLP) with stochastic parameters, unequal area facilities, and grid system modelin More

Facility layout is one of the most important Operations Management problems due to its direct impact on the financial performance of both private and public firms. Facility layout problem (FLP) with stochastic parameters, unequal area facilities, and grid system modeling is named GSUA-STFLP. This problem has not been worked in the literature so that to solve GSUA-STFLP is our main contribution. In this paper, we have first presented an integer nonlinear programming model which aims to minimize the cost of material handling. Then, a metaheuristic SA-based algorithm is proposed. Our proposed SA is able to generate feasible solutions by a local search operator to explore and exploit the solution space. Next, problems with different sizes besides the real case study have been solved. The computational results show the capability of the proposed SA to obtain the solutions with high quality in a short time. Manuscript profile

Open Access Article

14 - An Improved Optimization Model for Scheduling of a Multi-Product Tree-Like Pipeline
Mehrnoosh Taherkhani

20.1001.1.25885723.2019.11.2.14.5

In the petroleum supply chain, oil refined products are often delivered to distribution centers by pipelines since they provide the most reliable and economical mode of transportation over large distances. This paper addresses the optimal scheduling of a complex pipelin More

In the petroleum supply chain, oil refined products are often delivered to distribution centers by pipelines since they provide the most reliable and economical mode of transportation over large distances. This paper addresses the optimal scheduling of a complex pipeline network with multiple branching lines. The main challenge is to find the optimal sequence and time of product injections/deliveries at input /output nodes in order to satisfy product demands with minimum costs. We propose a mixed integer linear problem (MILP) approach that is capable of detecting the interface volumes in any pipeline and handling the simultaneous deliveries to distribution depots. Numerical examples are solved to validate the proposed model. Manuscript profile

Open Access Article

15 - Efficiency score assessment of Iranian Mining, Wood and Textile Industries
Malek Hassanpour

20.1001.1.25885723.2019.11.2.15.6

The Iranian Environment Protection Agency (IEPA) in collaboration with Iranian Industries Organization (IIO) need to design a relevant database for the industries information based on the initial screening of Iranian Evaluator Team (IET) in certain clusters. However, we More

The Iranian Environment Protection Agency (IEPA) in collaboration with Iranian Industries Organization (IIO) need to design a relevant database for the industries information based on the initial screening of Iranian Evaluator Team (IET) in certain clusters. However, we aware of this fact that all industrial projects should go through the Environmental Impact Assessment (EIA) after and along with screening levels. Therefore, current research concise the three clusters of Iranian industries data to further assessment towards Data Envelopment Analysis (DEA) empirically. To calculate the efficiency score were employed the Additive Ratio ASsessment (ARAS) model in combination with the DEA model along with using Friedman and Kendall tests as weighing systems. Using SPSS software led to estimate the values of weight regarding the inputs and outputs of materials flow. The combination of both mentioned models has expanded the path for determination of DEA score for the Iranian Wood and Cellulose Industries (IWCI), Iranian Mining and Aggregate Industries (IMAI) and Iranian Textile and Leather Industries (ITLI). Manuscript profile

Open Access Article

16 - On solving possibilistic multi- objective De Novo linear programming
Hamiden Khalifa

20.1001.1.25885723.2019.11.2.16.7

Multi-objective De Novo linear programming (MODNLP) is problem for designing optimal system by reshaping the feasible set (Fiala [3] ). This paper deals with MODNLP having possibilistic objective functions coefficients. The problem is considered by inserting possibilist More

Multi-objective De Novo linear programming (MODNLP) is problem for designing optimal system by reshaping the feasible set (Fiala [3] ). This paper deals with MODNLP having possibilistic objective functions coefficients. The problem is considered by inserting possibilistic data in the objective functions coefficients. The solution of the problem is defined and established under the using of efficient and necessary condition. Also, the relation between possibilistic levels corresponding to the solution is constructed. A solution procedure for solving the problem is proposed. A numerical example is given for illustration. Manuscript profile

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