Sharif Digital Repository

Deciding for the future is one of the key tasks that project managers must carry out. Accurate Estimate at Completion helps them make the right decision. Numeruse novel methods have been proposed for calculation of estimate at completion which most of them are based on Earned Value Management. The question is whether considering the resources, as the essential elements of activities and therefoe the project, would result in a more accurate Estimation. In this Thesis, we propose a method that uses resource performance and activity structure to calculate the Estimate at Completion. The method also forecasts future resource usage. To evaluate the proposed method, we generated fictitious... 

More than 60% of sales account for materials, and so the roles and responsibilities of the material managers have been recognized as more important within a firm or in a large scale project than before. However, in many purchasing situations, different considerations conflict with one another. In these situations material planning plays an essential role in the total cost minimization process. Here, the optimal material ordering policy for an item in a deterministic time-phased demand environment with all-units discount in purchasing is considered. Based on proven properties of the optimal order policy, a tree search procedure is designed to construct sequences of orders in the optimal... 

Small and medium companies generally start with a technical idea and usually without any specific strategy and mission . Commonly at this time short-term goals determine activities and current processes of company. As the time after time that the company grows it faces great problems because of the lack of strategy and long-term goals and also lack of correct definition of business processes. In this thesis with selecting one of these companies that provides products and services in information technology fields, after investigating current situation and problems we will redefine the mission and objectives with strategic approach. Then we offer a suitable business model that fits company... 

Foam concrete is a new covering layer that can be used for several purposes in civil constructions and because of its unique physical specifications, produces a light concrete in which is isolated against thermal conductivity ,with required strength and favorite quality.This cover is made of cement , sand ,water and foam(chemical substance that produces foam) . The foam is mixed with water in a special machine (mixer) with a high speed centrifugal rotation and produces very small stable bubbles called foam. While cement and sand are mixed in special mixer, makes a fluent concrete that can be used in place, metallic or plastic molds. After dehydration, in accordance with percentage of... 

Resource investment problem is one of problems in project scheduling which concerns with gaining minimum cost for accomplishing a project in a given time. Tardiness permitted with penalty cost makes this problem close to real world. This dissertation studied constraint of resources by restricted resources and tried to gain optimal level of restricted resource and middle resources start and finish time. This problem also permits tardiness with penalty cost. In construction projects, beside renewable and Non-renewable resources, there are workshops in which part of the work to carry out an activity, is done. These workshops include welding workshops and forming workshops in piping projects,... 

This research deals with the problem of scheduling independent preemptive jobs on identical parallel machines, to minimize the total completion time (makespan). The transportation of an interrupted job from a machine to another machine requires considering a constant transportation delay i.e., Pm|prmp(delay)| Cmax. This delay is called transportation delay. We propose a Mixed Integer Linear Programming formulation for the research problem in case of two machines i.e., P2|prmp(delay)| Cmax. Since the research problem is shown to be NP-hard, a particle swarm optimization (PSO) algorithm is applied to solve the problem approximately. Based on the frequency of using local search procedure, three... 

The construction industry is one of the main industries in Iran, and plays a fundamental role in Iran’s economy, because construction has impact on most of other industries by its vast value chain. Selecting right sets of projects is considerably crucial for construction organizations to successfully achieve their competitive advantages and corporate strategies. Due to limited resources and dynamic changes in Iran’s construction business environment, this kind of selection is quite challenging for construction organizations. Beside’s over hundreds of selection tools, techniques, and complex selection frameworks were developed or recommended by academics and practitioners to smooth the... 

The multi-mode resource-constrained project scheduling problem is one of the most complex and most widely used problems in the project scheduling knowledge area and operations research science. Recently, a new type of this problem which is called multi-skilled project scheduling problem has been introduced in the literature. The aim of MSPSP is to schedule the activities regarding the precedence relationships and multi-skilled human resource constraints in such a way that the need of each activity to a subset of skills should be met by the qualified employees. In this thesis, in addition to taking the constraints of the standard problem into account, we consider a state in which the... 

Risk is an uncertain event or condition that, if it occurs, has a positive or negative effect on a project’s objectives. Identification and assessment of risk in a measurable way are so important for project managers to decide better. This thesis studies how to identify and assess the project’s risks in Fishery industry based on the Project management body of knowledge (PMBOK 2008) as a global standard. Constructing an aquaculture site in Abadan city has some risks which are identified in the first steps of the study and in the following steps these risks will be prioritized by the use of qualitative analysis and figured out which risks have major effects on projects objectives. In last step... 

Process plants such as refineries and petrochemical plants are complex facilities consisting of equipment, piping systems, instruments, electrical systems, computers, and control systems. Process units design is mostly based on designer`s experience and design general criteria and standards. Using mathematical methods to optimize the design may have an effective role in cost reduction and it would give the designer some general view in case that the exact design is not applicable.
Optimization of Process units is described in this study. This optimization includes the exact location of each equipment, nozzle, pipe rack and also pipe route layouts. Mixed integer linear programming (MILP)... 

This project aims to study a situation in which several projects must be selected. The decision makers should select a subset of these projects taking into account the limitation of resources and scheduling. Project selection models generally do not consider schedule of project activities as part of selection process. On the other hand, except the cases where only one project is under process in each period, prioritizing the selected projects is not optimal not considering their scheduling. Projects scheduling in project activities level may increase the complexity of decision making for portfolio selection and expand the area of search for selection of projects portfolio. Therefore, all the... 

Project scheduling problems can be divided into different categories which one of the most important of them is resource investment problem. In this problem we are faced with a time limit for completion but resources are available unlimitedly and can be allocated to the project by specific cost. One of the most important constraints in real problems is the times that resources are available. In this research, resource investment problem considering calendar for resources has been investigated. Since resource investment problem is NP-Hard, after a brief overview of the different solutions, we used genetic algorithm to solve this problem. For this purpose, after determining chromosome... 

In this research, the risks of power plant projects are assessed with fuzzy approach. For this purpose, "Shirkooh Yazd combined cycle power plant" is chosen as the case study. First, the risks of power plant projects before the contract and during project execution are identified. Then these risks are categorized in a hierarchical breakdown structure. Subsequently, required information is collected from experienced professionals using questionnaires that used as the input data for risk qualitative analysis. In qualitative analysis, the risk probability and its impacts (containing time, cost and quality) are described by qualitative terms. After scaling them, the amount of each risk is... 

Risk management, one of the knowledge areas in project management, plays a key role in the success of projects in today’s unstable situation. The massive cost reduction achieved by risk management can manifest its importance even more in huge construction projects in gas and oil industry such as developments of power plants and petrochemical complexes. In this research, the effect of considering the correlation between risks and consequently the effect of risk action plans on other risks in their execution cost reductions has been demonstrated. A questionnaire has been designed, many experts have been interviewed, and using statistical methods, the risks’ interdependencies have been... 

In this project, we present a mathematical model for preemptive multi-mode resource-constrained project scheduling problem considering fast tracking (PMRCPSP-FT). The number of activity preemptions could be defined in the model. We used two types of resources in our model: Renewable resources and Non-renewable resources. Each activity can be accomplished in just one mode and each mode represents activity resource requirements, its duration and its maximum number of allowable preemptions. The objective is to minimize the project makespan. Considering the complexity of the problem, the exact solution is not achievable for big or real size problems. We use a genetic algorithm to solve the... 

Piping process is the most important part of industries projects which pay attention to construction and installation of industrial pipelines and its facilities. In the meantime, due to increasing demand of industrial units to construction and development projects, planing and scheduling the piping is necessary. We review and discuss various aspects of the piping process, optimization process and the related scheduling literature that is called Flexible Job Shop Scheduling Problem. Then, to solve the problem, considering the real world assumptions, a mathematical model, is developed and a heuristic algorithm is introduced. Also, in order to determine an appropriate bound for the optimal... 

The subject of project scheduling is one of classic subjects in project management, and It contains the wide range of optimization problems. Using making changes in variables and constraints , it is possible to create new problems which seem better in the real world. Project tasks need resources for implementation. In some cases, it is considered that any time there are enough resources. In some other cases, it assumes, resources are limited, and resource optimum purchasing is the purpose, which this kind of issues is named resources investment problems (RIP). In this research it assumes, project necessary resources, are rented and renting costs depends on the time of owning. In standard... 

One of the methods that we used today to manage project are calculating project progress. By which we can calculate the actual progress of project by comparison the actual plan with the schedule plan. If the actual progress,measured with less error, then the control of project done with high accuracy.Project progress are calculated in control account. For this reason, if the number of control account increased, the accuracy of the calculation increased and on the other hand whatever this control account increase the amount of time used to collect information also increases. In this study, we are looking to create mathematical model that in addition increases the accuracy of measurement,also... 

Project Scheduling is one of the most important branches of the operational research and management science and scheduling the project activities is considered to be one of the branches of project scheduling issue. Different goals are considered in project scheduling, but financial goals are one of the most necessary criterions in this research area.This study investigates the matter of project procurement scheduling considering incremental discount model and also storehouse space limitation with the aim of minimizing the costs of ordering, maintaining and purchasing materials required for the project.Project procurement scheduling issue, restrictions included, is an NP¬hard issue.... 

Manage time, cost and quality, project managers are a major concern for the violation of any of the causes to bring costs and fines will be detrimental. Collect all the main factors contributing to delays in construction projects to three main factors employer, contractor and external factors reached. An algorithm is presented in this study are presented in addition to the reasons and factors affecting the delay of engineering documents, the contribution of each factor in the delay of the project will help the project. Implementation algorithm In the Pargas farayand Company of Pakaging projects sulfur solidification