Sharif Digital Repository

Aabsal Co. was established in north east of Tehran in 1956, under the name of Loab Iran Private LTD.  Co.  and  continued  its  activity  in  manufacturing  enameled  dishes,  bowl,  tea  pots  and  etc.  until 1964. In  this  thesis  we  have  paid  attention  to  basics  of  TPM  and  how  to  implement  PM  procedures.  First we have paid attention to all the maintenance forms and how these forms work together in the company, and then the relationship between departments sections like manufacturing and maintenance are considered. Finally we have attempted to implement TPM. For this purpose we have taken a section of the factory as a pilot plant and have started to implement TPM there to... 

One of the most useful methods in metal forming is Sheet Metal Forming. Use of Forming limit diagrams (FLD) in designing is a conventional method. Therefore many experimental and theoretical efforts have been carried out in order to investigate the FLDs. Many ways to obtain this FLDs and their effective parameters have been studied. But the stress state at these studies is planar which lead to an untrue model for several metal forming process such as incremental sheet forming. With this technique, the forming limit curve (FLC) appears in a different pattern, revealing an enhanced formability, compared to conventional forming techniques. Therefore, in this study, the effect of through... 

In process of making prosthetic limb, each of the prosthetic limbs must be costume fitted and built since each amputation of the patient is unique. The design and fabrication process of artificial limb consists of several different steps and begins with a precise measurement process that will be used to design the prosthetic limb. If possible, a prosthetist begins taking measurements before the patient's limb is even amputated, so that the fabrication process can get started. Today, much research which has been done in Augmented Reality and 3D scanning technologies shows that these technologies can help people with disabilities to have better experience in their life by using them in... 

Massive-MIMO and C-RAN are the two technologies which will be among most important parts of fifth generation (5G) stsrems. They will find widespread uses in future years. However, data transfer rate between these two technologies is a challenging problem. Also channel estimation is crucial in massive-MIMO systems. In this research, the problem of estimating the channel and the problems with the data transfer rate between these two technologies are investigated. We propose using 1-bit quantizers to solve the rate problem and also an algorithm with perfect performance in aspect of error rate is proposed. The mentioned algorithm is implemented on GPUs, which are available at C-RANs and resulted... 

A new heuristic controller, called nonlinear model predictive control based on gravitational search algorithm, is proposed for nonlinear systems. Nonlinear model predictive control involves the solution at each sampling instant of a finite horizon optimal control problem subject to nonlinear system dynamics and constraints. The new controller formulates nonlinear model predictive control problem as a single stochastic dynamic optimization problem and uses a system of virtual masses to find the best control signal at each sampling instant. For this purpose, a cost function is defined to evaluate each point of the search space. This function minimizes simultaneously the tracking error, control... 

Today, the correct management of construction projects in IRAN's water industry has become a severe concern for its managers. Construction projects of the water industry constitute a considerable part of the country's construction industry. Several significant Issues such as operation management, water industry projects, correct management of resources, crisis management in the water industry, increased productivity and useful life of structures, increasing productivity, and preventing water loss are among the determinative challenges in construction projects in Iran. One of the new methods for the correct management of the life cycle of projects in this area is the use of Building... 

Nowadays, the manufacturing environments have been faced with the globalization paradigm. This paradigm urges the new necessities for manufacturing environments like concentration on customer demands, focus on increase of quality and its continuous improving trend and shortening the products’ lifecycle. These necessities have been considered by many researchers and have led to different ideas in the field of effective and efficient product development and after sales services. Computer Integrated Manufacturing (CIM) is known as the major research field for study, development and proposal of effective IT solutions to fulfill the aforementioned necessities. This research filed has resulted to... 

Benefiting from the great potential of the mathematical tool of fractional calculus, fractional order proportional integral (FOPI) and proportional integral derivative (FOPID) controllers have been proposed as the next generations for the popular PI and PID controllers. On the other hand, the integral performance indices such as the integral square error (ISE), integral square time error (ISTE), integral absolute error (IAE) and integral time absolute error (ITAE) are commonly used in design and evaluate of the performance of practical control systems. Considering these points, the present thesis deals with optimal tuning of the free parameters of fractional order PI and PID controllers, to... 

The increasing significance and deployment of knowledge management(KM) is the main reason for selecting the topic of this research. This research tries to analyse the dimensions and KM implementation methods in press section of maintenance department in Saipa company. This study has a qualitative approach and the method is based on a case study. Data has been collected by questionnaires. Two questionnares have been provided in this research and distributed among different staff of press section in maintenance department. The concept of knowledge management maturity is applied and the goal of first questionnaire is based on this concept. The level of KM maturity is assessed via this... 

Five-Level Active-Neutral-Point -Clamped (5L-ANPC) converter is used for medium-voltage and high-power applications. In many of these applications, availability and robustness against fault are the most important issues. On the other hand, this converter is made of a large number of power semiconductor switches, diodes and capacitors which could increase the failure probability. Thus, fault detection of power circuit elements is necessary for fault tolerant operation of the converter. In this thesis, following an introduction to the topology and operation principles of Five-Level Active Neutral point clamped converter, a novel open-circuit fault detection and localization method is... 

Lean Management is a set of modern procedures that uplifted Japanese manufacturers' status in global markets. The core principle of lean management is to eliminate every process or operation which creates no value, directly and indirectly. To this day, lean has been more focused on production. But eliminating the wastes in service organizations in crucial, due to nature of service. In this thesis, first the lean concept and the Middle East bank is discussed and a literature review on lean studies is presented. Then a vision for the future is envisioned and a questionnaire for conducting a Corporate Diagnosis is developed. In the next step, a lean management system for the bank is implemented... 

The main effort of this thesis is to present a numerical method to simulate and implement a special type of controllers, called proportional-weighted integral (PWI) controllers. For this purpose, at first mathematical equations of the fractional order proportional-integral controllers have been investigated in the time domain, and then by generalization of these controllers, the PWI controllers are achieved. Next the discretization of these controllers are carried out and the performance of the controllers are simulated by means of this discretization and comparison between these controllers and the conventional PI controllers has been held. After that a method for estimation of these... 

The Active Learning Method is in fact an adaptive recursive algorithm which embodies a Multi Input and a Single Output (MISO) system as in a fuzzy combination of several Single Input systems and Single Output systems (SISO), and by utilizing a fuzzy technique of Ink Drop Spread tries to explore and extract input to output transfer function behavior in the system of a single-input to a single-output. Although in simulation state, the speed of this model is set at a much higher speed in comparison to other presented models, still is slower than the processing speed of human brain. In regards to hardware implementation, also there remain the fundamental implementation challenges through more... 

In addition to investigating the overall situation of healthcare information systems (HIS) in Iranian hospitals, in this thesis the goal is to determine the key elements of success and failure in the implementation of HIS. With the advent of the computer systems in Iran and due to the successful and unsuccessful experiences of organizations, the necessity of detecting the influential elements in this field is perceived even more than before. Another importance of this research is because of the essential role of the cultural and social factors in the success of these systems; this claim can be justified by observing different results founded by researchers from different countries. In this... 

Environmental review, surveying land resources and the military mission requires high resolution imaging of large areas. in many cases, imaging should be performed during the night or in poor weather. Synthetic Aperture Radars (SAR)using long range propagation characteristics of radar signals and the complex information processing capability of modern digital electronics to provide high resolution image. The radar complements photographic and optical imaging capabilities because of them does not the time constraints, work and the weather. one of the most important methods for the extraction of synthetic aperture radar images by the method of imaging is the SPECAN algorithm. an important... 

The primary purpose of the present thesis is to provide the feasibility of experimental determination of Counterflow flames dynamic response to acoustic excitations. Following this cause, an excitable counterflow burner test platform was designed, fabricated, implemented, and finally validated. The rich scientific literature associated with counterflow burners, the simple structure of the flame, conceivability of numerical simulation analysis in one, two, or three dimensions, the simplicity of structure among fundamental flames which are correspondingly in resemblance with industrial flames and finally the ability of universalization of scientific result to industrial flames are the reasons...