Original Article
Non-linear Optimization
Narges Araboljadidi
Abstract
In this paper, we present a method for charaterizing the solution set of nonconvex optimization problems via their dual problems. In fact, the constrainted optimization problem which is considerd has pseudoconvex and locally Lipschitz functions, which are not necessarily convex and smooth, and include ...
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In this paper, we present a method for charaterizing the solution set of nonconvex optimization problems via their dual problems. In fact, the constrainted optimization problem which is considerd has pseudoconvex and locally Lipschitz functions, which are not necessarily convex and smooth, and include a wide class of non-convex non-smooth functions. In the proposed method, a dual problem is formulated to characterizations of the solution set of the primal problem in a mixed type of Wolfe type and Mond-Weir type. First, we introduce some of the properties of the Lagrangian functions associated to these problems and then we explain the proof of the characterization of their solution sets.
Original Article
Linear Optimization
Sajad Moradi; Gholamreza Karamali
Abstract
Shortest path problem is one of the practical issues in optimization, and there are many efficient algorithms in this area. In this issue, a network of some nodes and arcs is considered in which, each arc has a specific parameter such as distance or cost. The main objective is to find the shortest or ...
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Shortest path problem is one of the practical issues in optimization, and there are many efficient algorithms in this area. In this issue, a network of some nodes and arcs is considered in which, each arc has a specific parameter such as distance or cost. The main objective is to find the shortest or least costly route between two distinct points. By considering an additional parameter and adding a new limitation, as a capacity constraint, the problem will be closer to the real world condition. This extended issue is known as the constrained shortest path problem and has a higher complexity order and practical algorithms are needed to solve it. In this study, an effective algorithm is presented that obtains the optimal solution within a short time. In this method, a repetitive pattern is used so that, in each iteration, the relaxed model, after adding a logical cut, is solved. The results of the implementation of the proposed algorithm on different networks show its efficiency.
Original Article
Network Optimization
Javad Pourqasem; Soheil Fakheri
Abstract
Peer-to-peer (P2P) systems have grown significantly in recent years due to the ability to share multiple resources. Using the super-peer nodes in peer-to-peer networks has increased the efficiency of these networks. The main problem in these systems is the selection of high-capacity nodes as the ...
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Peer-to-peer (P2P) systems have grown significantly in recent years due to the ability to share multiple resources. Using the super-peer nodes in peer-to-peer networks has increased the efficiency of these networks. The main problem in these systems is the selection of high-capacity nodes as the super-peer node to join other nodes. The optimal choice is dependant on various parameters such as heterogeneous capacity and dynamic nature of the network. Given the predominant position of the super-peer nodes in the network, the selection of the top node requires a protocol that is aware of the capacity of the nodes. In this paper, we present a method for selecting a super-peer node based on the SG-2 model utilizing the broadcast-service and distance-delay-based Gossip protocol, and use the status messages between neighboring nodes, and search messages to select the most powerful node. Using this method, the efficiency of peer-to-peer networks will increase and the time of convergence to the optimal overlay network will be reduced.
Original Article
Location Modeling
Reza Hasan Zadeh; Shirin Alizade
Abstract
Crises are the inevitable realities of human life; which is an accident that occurs naturally or suddenly or increasingly by human and to address it, there is a need for urgent and fundamental measures.When the crisis occurs, pre-determined storage locations will play an important role in relief; therefore, ...
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Crises are the inevitable realities of human life; which is an accident that occurs naturally or suddenly or increasingly by human and to address it, there is a need for urgent and fundamental measures.When the crisis occurs, pre-determined storage locations will play an important role in relief; therefore, the selection of suitable places for warehouses is one of our main goals in this research. In this research, a bi-objective linear programing model with integer variables is developed. The proposed model attempt to minimize total cost along with maximizing the minimum weight of open shelter areas while deciding on the location of shelter areas, the assigned population points to each open shelter area and controls the utilization of open shelter areas. In order to solve proposed model, some of well-known multi-objective, exact methods includes a weighted sum method, LP-metric method, and goal programing approach are employed.Finally, the best open shelter areas with considering the minimum cost is obtained, which these results can be useful for crisis organizations.
Original Article
Strategic Planing
Fereydoon Rahnamay Roodposhti; Mohsen Imeni; Shadi Sayadmanesh
Abstract
Balanced Scorecard used as a tool of strategic assessment and suggested that all performance of organizations should not only be studied financial metrics but must non-financial metrics also be considered. BSC concept encompasses a larger area of the business segment. However, Balanced Scorecard is in ...
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Balanced Scorecard used as a tool of strategic assessment and suggested that all performance of organizations should not only be studied financial metrics but must non-financial metrics also be considered. BSC concept encompasses a larger area of the business segment. However, Balanced Scorecard is in practice very complex and in terms of the measurement system and implementation is very successful. But it could be concluded that there are still shortcomings which some scholars have identified it. For this reason were suggested innovative methods to reform the traditional model and performance indicators, such as Balanced Scorecard Knowledge-Based System (BSCKBS), the Proactive BSC Methodology (PBCSM), Lean Balanced Scorecard Card (LBSC), Balanced IT Scorecard (BITS), BSC - Analytic Network Process (ANP) and BSC - Control Objectives for Information Technology (COBIT). In the present study, innovative methods were introduced for reform the traditional model of BSC according to historical recognition method, were studied. The results show that in recent year's wealth of researches is done on the use of new approaches in the field of management accounting in particular BSC, with the aim of eliminating defects in the traditional model and help in decision making for strategic decision making.
Original Article
Optimal Control
Hamid Tabatabaee; Mahdi Memari
Abstract
The problem of solving optimal control of Singular problems in the classic method has a complexity that is solved by approximation of the equations in the problem with orthogonal bases instead of solving the dynamic equation system of a set of static problems. In return for a more relaxed solution, it ...
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The problem of solving optimal control of Singular problems in the classic method has a complexity that is solved by approximation of the equations in the problem with orthogonal bases instead of solving the dynamic equation system of a set of static problems. In return for a more relaxed solution, it will face some errors in the computation .however, it has an appropriate precision. Legendre and Fourier series are presented using the specifications of the Fourier transform of Legendre and Fourier series . In this algorithm, the state variables, and the state - derivative variables and the control vector are extended by the orthogonal basis of Legendre and Fourier series with unknown coefficients. in order to compute optimal control vector and optimal path of linear Singular systems with quadratic cost function , we are introduced by using the properties of orthogonal functions introduced by the coefficients and .using the proposed method , the system dynamics are converted into algebraic equations and the problem of dynamic optimization of dynamic space has been mapped to static space optimization problem with quadratic cost function and linear constraints . First, it is used to solve the problem using an orthogonal basis of raw material and then the problem solving with orthogonal basis of Fourier series is repeated. Finally, the application and effectiveness of the proposed method are presented.
original-application paper
Decisions in new businesses
Zahra Danesh; Hadi Shirooye Zad; Negin Berjis
Abstract
Organizational culture is one of the core values in an organization and it makes organizations different .Organizational culture plays an underlying role in enhancing the quality of service delivery, and enhances cohesion and increases productivity and innovation in the organization. The main purpose ...
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Organizational culture is one of the core values in an organization and it makes organizations different .Organizational culture plays an underlying role in enhancing the quality of service delivery, and enhances cohesion and increases productivity and innovation in the organization. The main purpose of this study is to determine the organizational culture level at Golnour Company by using Denison's model. The research is of theoretical and applied type and the data used are of quantitative type, the Denison organizational culture questionnaire was used for data collection. The statistical population of the study consists of managers and staff of Glenour Company in Isfahan province. The research data were analyzed by Kruskal-Wallis test, plotting histograms, concentration and dispersion data analysis and Spearman correlation test. The results show that all indicators and items are strongly correlated and neglecting the poor performance in each of the indicators will affect other aspects of organizational culture and will lead to undesirable intra-organizational and extra-organizational outcomes in different dimensions.