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    (Identifying Factors Influencing Industrial Programs Delay Case Study (South Pars Phase 17 & 18 Development

    , M.Sc. Thesis Sharif University of Technology Turkan, Masoud (Author) ; Haji Yakhchali, Siamak (Supervisor)
    Abstract
    Industrial programs are known as engine of development plans in Iran. These types of programs also known as mega projects that have multi dimension nature of the project. In fulfillment of doing mega project, consideration on many dimensions as several engineering process, complex project management issues, social responsibilities, cultural issues, and many other affecting dimensions should be done.As a point of view in successful project, the management (HAROLD KERZNER, 2006) requires finishing projects at cost, time, and quality and so on, but success of the industrial programs and mega projects also have effects on countries economy and improvements.For a country development, it is needed... 

    Identifying Root Causes of Residential Building Project Delays in Mashhad

    , M.Sc. Thesis Sharif University of Technology Farmani, Nima (Author) ; Alvanchi, Amin (Supervisor) ; Haji Yakhchali, Siamak (Co-Advisor)
    Abstract
    The residential construction projects are an important and extraordinary part of the economy of Iran. Due to their important role and lots of problems that these kinds of projects face, this research was conducted. Delay is one of the main problems in these projects. In order to identify the causes of delay and propose recommendations to minimize it in Mashhad, Iran, a comprehensive literature review and interview with experts were conducted. One hundred and eight factors were identified and categorized into nine main groups. Based on the identified factors, a questionnaire survey was prepared, developed and distributed among the people who were active in the residential construction... 

    Optimal Batch Production for a Single Machine System with Rework

    , M.Sc. Thesis Sharif University of Technology Haji, Babak (Author) ; Haji, Ali Reza (Supervisor)
    Abstract
    This research attempts to develop the optimal solution for an inventory problem consisting of a single machine which produces items some of which may be defective. We assume that no shortages are allowed and all defective items are to be reworked. Setup cost for rework and waiting time of defectives are considered. This research consists of two different parts. In the first part we consider two different policies where in the first policy in each cycle after the regular production the machine is setup for the rework of defectives of the same cycle. In the second policy several cycles constitute a period. All the defectives produced in the period are reworked in the last cycle of that period.... 

    Optimal batch production with rework and non-zero setup cost for rework

    , Article 2009 International Conference on Computers and Industrial Engineering, 6 July 2009 through 9 July 2009 ; 2009 , Pages 857-862 ; 9781424441365 (ISBN) Haji, B ; Haji, R ; Haji, A ; Sharif University of Technology
    2009
    Abstract
    This paper attempts to develop the optimal solution for an inventoryproblem consisting of a single machine which produces items some of which may bedefective. We assume that no shortages are allowed and all defective items areto be reworked. Setup cost for rework and waiting time of defectives areconsidered. We consider two different policies where in the first policy in eachcycle after the regular production the machine is setup for the rework ofdefectives of the same cycle. In the second policy several cycles constitute aperiod. All the defectives produced in the period are reworked in the last cycleof that period. At the end of the rework cycle the whole process starts allover again. One... 

    One-for-one period policy in a two-echelon inventory system with commoncycle and poisson demand rate for retailers

    , Article 2009 International Conference on Computers and Industrial Engineering, CIE 2009 ; 2009 , Pages 831-834 ; 9781424441365 (ISBN) Haji, R ; Tayebi, H ; Haji, B ; Sharif University of Technology
    2009
    Abstract
    This paper deals with a two-echelon inventory system consisting of onesupplier and N retailers. Each retailer faces an independent Poisson demand withthe same rate and applies a new ordering policy called one-for-one- periodordering policy for its inventory control. In this ordering policy the ordersize is equal to one and the time interval between any two consecutive ordersforms a common fixed cycle. Thus, the supplier faces a deterministic demand andadopts a deterministic inventory policy. At each cycle he orders a batch of sizeN to his own supplier. Upon receipt of each batch he sends 1 unit of theproduct to each retailer with a transportation cost. In this paper, for theabove system we... 

    Revenue sharing contract for a VMI with one for one period policy

    , Article Cogent Engineering ; Volume 5, Issue 1 , 2018 , Pages 1-19 ; 23311916 (ISSN) Haji, A ; Afzalabadi, M ; Haji, R ; Sharif University of Technology
    Cogent OA  2018
    Abstract
    In this article, we design a revenue-sharing contract to coordinate inventory control decisions in a serial supply chain consisting of one supplier, one vendor, and one retailer. We assume that the retailer faces Poisson demand and his unsatisfied demands will be lost. The retailer applies one-for-one period policy in which he constantly places an order for one unit of product to the vendor in a predetermined time interval which results in a deterministic demand for the vendor. Vendor orders the required quantity from supplier which will be immediately received at the vendor’s warehouse. Solution procedures are developed to find the equilibrium in the vendor managed inventory program with a... 

    Pricing and inventory decisions in a vendor managed inventory system with revenue sharing contract

    , Article Uncertain Supply Chain Management ; Volume 6, Issue 3 , 2018 , Pages 299-320 ; 22916822 (ISSN) Haji, A ; Afzalabadi, M ; Haji, R ; Sharif University of Technology
    Growing Science  2018
    Abstract
    In this paper, we design a revenue sharing contract to coordinate pricing and inventory control decisions in a serial supply chain consisting of one supplier, one manufacturer and one retailer. We assume that the retailer faces Poisson demand and his unsatisfied demands will be lost. The retailer applies one-for-one period policy in which he constantly places an order for one unit of product to the manufacturer in a predetermined time interval which results in a deterministic demand for the manufacturer. Solution procedures are developed to find the equilibrium in the Vendor Managed Inventory (VMI) program with a revenue sharing contract, in which no party is willing to deviate from for the... 

    Developing a partial backlogging deteriorating inventory model with selling price dependant demand rate and cycle length dependant selling price

    , Article 2008 IEEE International Conference on Industrial Engineering and Engineering Management, IEEM 2008, Singapore, 8 December 2008 through 11 December 2008 ; January , 2008 , Pages 198-202 ; 9781424426300 (ISBN) Haji, A ; Sabahno, H ; Haji, R ; Sharif University of Technology
    2008
    Abstract
    In this paper, we develop an inventory model with price dependant demand rate, under time value of money and inflation, finite time horizon, exponential backlogging rate and exponential deterioration rate with the objective of maximizing the present worth of the total system profit. Using a dynamic programming based solution algorithm, we are able to find the optimal sequence of the cycles and also to obtain different optimal selling prices and optimal order quantities for the cycles with unequal lengths, which have never been done before for our model. We also use a proper numerical example to show accuracy of the solution procedure. © 2008 IEEE  

    One-for-one period policy and a series of suppliers

    , Article 2009 International Conference on Computers and Industrial Engineering, CIE 2009, 6 July 2009 through 9 July 2009, Troyes ; 2009 , Pages 902-906 ; 9781424441365 (ISBN) Haji, R ; Pirayesh Neghab, M ; Haji, A ; Sharif University of Technology
    2009
    Abstract
    The purpose of this paper is to adopt and analyze a new ordering policycalled one-for-one-period policy in a multi-echelon supply chain consisting ofone retailer and a series of TV suppliers. The main advantage of adopting theone-for-one-period (7,7) ordering policy for retailers is the elimination ofuncertainty for supplier which leads to total elimination of the safety stocksat all suppliers. This in turn leads to the reduction of the total system costsand in case any supplier's ordering cost is negligible it can even eliminate theneed for him to carry any inventory. In addition to this advantage, thenumerical results show that the application of this new policy for the retailerleads to... 

    Optimal batch production with minimum rework cycles and constraint on accumulated defective units

    , Article 2009 IEEE/INFORMS International Conference on Service Operations, Logistics and Informatics, SOLI 2009, Chicago, IL, 22 July 2009 through 24 July 2009 ; 2009 , Pages 633-638 ; 9781424435418 (ISBN) Haji, B ; Haji, A. R ; Haji, R ; Sharif University of Technology
    2009
    Abstract
    This paper deals with the issue of economic batch quantity (EBQ) in a single machine system in which defective items are produced in each cycle of production. The accumulated defective items produced in a period, consisting of several equal cycles, are all reworked in the last cycle of this period called the rework cycle. At the end of each period the whole process will start all over again. We assume that there is a limitation on the total defective items. We also do not adopt the restriction that the rework process rate be equal to the normal production rate. In addition we assume that there is a set up time for rework process. Further we assume that the number of rework cycles be as small... 

    Economic production quantity with accumulated rework

    , Article 36th International Conference on Computers and Industrial Engineering, ICC and IE 2006, Taipei, 20 June 2006 through 23 June 2006 ; 2006 , Pages 4196-4203 Haji, R ; Tavakol, A. R ; Haji, B ; Sharif University of Technology
    2006
    Abstract
    This paper deals with the issue of economic batch quantity (EBQ) in a single machine system in which defective items are produced in each cycle of production. The defective items produced in the first N cycles are accumulated at the end of the Nth cycle and are all reworked in a separate cycle called the rework cycle which has the same length as the other cycles and begins just at the end of the Nth cycle. At the end of the rework cycle the whole process will start all over again. For this system, assuming no shortages are permitted we obtain the economic batch quantity which minimizes the total cost  

    Multi-Echelon Mixed-loop Supply Chain Network Design under Disruption Conditions

    , M.Sc. Thesis Sharif University of Technology Beheshti, Saeed (Author) ; Haji, Rasoul (Supervisor) ; Haji, Alireza (Supervisor)
    Abstract
    Fulfilling the demands of customers, used to be the main purpose of Supply Chain Network Designers. Soon after that, the environmental concerns created the concept of Reverse Logistic in order to prevent goods from being scattered in the environment after their disposal. Governmental regulations and people's concerns, forced the factories to gather the created pollutions of the environment. They gradualy confessed the positive impacts of these ruturns on their financials. The flow of forward and reverse logistics establishes a Closed-Loop in which the returning economical circumstances were transferd into original factories. Later, Open-Loops were created. In open-loops the returns have to... 

    Inventory Control Dynamic Models in Decentralized Supply Chain with Coordination

    , Ph.D. Dissertation Sharif University of Technology Afzalabadi, Maryam (Author) ; Haji, Alireza (Supervisor) ; Haji, Rasoul (Co-Advisor)
    Abstract
    Although inventory control under discrete demand in dynamic quantities and time intervals are very common in reality, existing literature has largely ignored them. In this thesis, we investigate the inventory control decisions in a two echelon supply chain. The vendor supplies a product to several retailers, buying discrete quantities in pre-determined time intervals. The order quantity and order cycles for each retailer can be different from others. We have developed a new efficient algorithm to find the optimal ordering policy involves the scheduling and the order quantity of vendor to his supplier to minimize his cost function in infinite time horizon. Moreover, we have designed a revenue... 

    Efficient biodegradation of naphthalene by a newly characterized indigenous achromobacter sp. FBHYA2 isolated from Tehran oil refinery complex

    , Article Water Science and Technology ; Volume 66, Issue 3 , March , 2012 , Pages 594-602 ; 02731223 (ISSN) Farjadfard, S ; Borghei, S. M ; Hassani, A. H ; Yakhchali, B ; Ardjmand, M ; Zeinali, M ; Sharif University of Technology
    IWA Pub  2012
    Abstract
    A bacterial strain, FBHYA2, capable of degrading naphthalene, was isolated from the American Petroleum Institute (API) separator of the Tehran Oil Refinery Complex (TORC). Strain FBHYA2 was identified as Achromobacter sp. based on physiological and biochemical characteristics and also phylogenetic similarity of 16S rRNA gene sequence. The optimal growth conditions for strain FBHYA2 were pH 6.0, 30°C and 1.0% NaCl. Strain FBHYA2 can utilize naphthalene as the sole source of carbon and energy and was able to degrade naphthalene aerobically very fast, 48 h for 96% removal at 500 mg/L concentration. The physiological response of Achromobacter sp., FBHYA2 to several hydrophobic chemicals... 

    Prediction of Financial Markets Using Combination of Artificial Intelligence and Technical Analysis

    , M.Sc. Thesis Sharif University of Technology (Author) ; Haji, Alireza (Supervisor)
    Abstract
    Generally, nowadays, machine learning methods are used in many different areas for their superiority over other methods of prediction. Although being a tough task, stock market prediction with machine learning approaches is being spread due to satisfying results published ever yday. Machine learning methods usually use varied kinds of data ,including structured data such as market data, technical indicators and some fundamental data as well as unstructured one entailing text and graph data in order to enhance their predictability capacity. In this thesis we aimed to find out more about the importance and the contribution of structured data in prediction and we tried to attain a framework... 

    A study on Warm Rolling Behavior of an Austenitic Stainless Steel and the Mechanical Properties of the Rolled Product

    , M.Sc. Thesis Sharif University of Technology Ghadamgahi, Mojtaba (Author) ; Serajzade, Siamak (Supervisor)
    Abstract
    In this study, thermo-mechanical behavior of an austenitic stainless steel AISI316L was investigated using mathematical modeling and experimental analysis during warm rolling process. First, the thermo-mechanical analysis was carried out employing the finite element software, Abaqus CAE, to assess temperature, strain, velocity and stress distribution during rolling. Then, rolling operations on 316L austenitic steel were performed under different working conditions while mechanical testing as well as microstructural observations were made on the rolled steels. Using simulation results and practical data, microstructural events and mechanical properties after warm rolling of stainless steel... 

    Introducing a new ordering policy in a two-echelon inventory system with Poisson demand

    , Article International Journal of Production Economics ; Volume 117, Issue 1 , 2009 , Pages 212-218 ; 09255273 (ISSN) Haji, R ; Neghab, M. P ; Baboli, A
    Elsevier  2009
    Abstract
    In this paper we introduce a new ordering policy for inventory control in a two-echelon inventory system consisting of one central warehouse and a number of non-identical retailers. The warehouse uses a modified one-for-one policy, but the retailers apply a new policy which is different from the traditional inventory policies described in the literature of inventory and production control systems. In this system, each retailer constantly places an order for one unit of product to the central warehouse in a pre-determined time interval; i.e., the time interval between any two consecutive orders from each retailer is a fixed number and the quantity of each order is one. We then show how the... 

    Stabilized Meshless Local Petrov-Galerkin (MLPG) method for incompressible viscous fluid flows

    , Article CMES - Computer Modeling in Engineering and Sciences ; Volume 29, Issue 2 , 2008 , Pages 75-94 ; 15261492 (ISSN) Haji Mohammadi, M ; Sharif University of Technology
    2008
    Abstract
    In this paper, the truly Meshless Local Petrov-Galerkin (MLPG) method is extended for computation of steady incompressible flows, governed by the Navier-Stokes equations (NSE), in vorticity-stream function formulation. The present method is a truly meshless method based on only a number of randomly located nodes. The formulation is based on two equations including stream function Poisson equation and vorticity advection-dispersion-reaction equation (ADRE). The meshless method is based on a local weighted residual method with the Heaviside step function and quartic spline as the test functions respectively over a local subdomain. Radial basis functions (RBF) interpolation is employed in shape... 

    Meshless local petrov-galerkin (MLPG) method for incompressible viscous fluid flows

    , Article 2006 2nd ASME Joint U.S.-European Fluids Engineering Summer Meeting, FEDSM 2006, Miami, FL, 17 July 2006 through 20 July 2006 ; Volume 2006 , 2006 ; 0791837831 (ISBN); 9780791837832 (ISBN) Haji Mohammadi, M ; Sharif University of Technology
    2006
    Abstract
    In this paper, the truly Meshless Local Petrov-Galerkin (MLPG) method is extended for computation of unsteady incompressible flows, governed by the Navier-Stokes equations (NSE), in vorticity-stream function formulation. The present method is a truly meshless method based only on a number of randomly located nodes. The formulation is based on two equations including stream function Poisson equation and vorticity advection-dispersion-reaction eq. (ADRE). The meshless method is based on a local weighted residual method with the Heaviside step function and quartic spline as the test functions respectively over a local subdomain. Moving Least Square approximation (MLS) is employed in shape... 

    Prediction of Temperature and Strain Distribution in the Warm Rolling of Austenite Stainless Steel

    , M.Sc. Thesis Sharif University of Technology Nemati, Elham (Author) ; Serajzadeh, Siamak (Supervisor)
    Abstract
    In this research, the hot and warm rolling of stainless steel 304 was studied. First the rolling process was simulated using Finite Element Method software ABAQUS and the distribution of temperature and strain in the process under discontinuous conditions were predicted. Next, hot and warm rolling of stainless steel 304 under different conditions was carried out. Specimens were cut and subject to mechanical testing, metallography and electron microscopic studies. Data obtained from these experiments and the predicted trends from ABAQUS were compared, therefore studying the effect of different parameters on the microstructure and mechanical properties of the rolled specimen. Results indicate...