Sharif Digital Repository

Profile Monitoring is a new research topics in the field of statistical process control. In many applications of statistical quality control, sometimes quality of a process or product described by a relationship between a response variable and one or more independent variables.The researchers call this relationship profile. The study seeks to demonstrate that monitoring profiles In addition, the industry can be effective in medical field and improves control of the patient's condition by a doctor. Profiles are usually modeled with a linear regression equation, non-linear or polynomial. finally, the results of this study, using actual data, models and methods to predict and control... 

Cellular Manufacturing System (CMS) is one of the most practical manufacturing systems based on the Group Technology (GT) concept. In this thesis, a CMS is evaluated and analyzed through the proposing new mathematical models. A cellular manufacturing system includes four main sub-problems; Cell formation (CF), Group Scheduling (GS), Group Layout (GL) and Resource Assignment (RA). In this paper two problems of CF and RA are studied and discussed.At first, a new mathematical model is proposed for a CF problem. The objectives are the minimization of inter-intra cell part trips, machine breakdown cost, tool consumption cost and the reconfiguration cost. Multi-functional machines unreliability is... 

Operating rooms has always been considered as one of the most expensive, yet most profitable part of a hospital. Since many units in the hospitals are related to the operating room, improving efficiency in the operating room will result in increased efficiency in other units, so offering proper solutions in this area is very important. Suitable Planning and scheduling has a great impact on increasing the level of service and efficiency of the hospital. in this thesis, a mixed integer programming model for scheduling weekly elective patients in the surgical theater with the objective of maximizing the number of elective patients for the surgery and also the workload of the operating room... 

The everyday increasing electricity consumption of household and industrial sectors across the world, and also the limited generation capacity and fuel supplies has led electricity companies, whether in private or government sectors, to focus deliberately on power generation planning, its costs, risks and constraints Because of many reasons including high efficiency, low cost of capital investment, expeditious permitting, and operation flexibility of gas-fired generating units, electricity companies prefer them to old ones like coal-fired or oil-fired generating units. Thus natural gas has gained a significant share in the portfolio of electricity generation fuel resources, and it is... 

Reviewing the literature on air traffic flow management shows that reducing flight delay is one of the main challenges facing air transportation systems. This is due to the high cost of incurring delays. At the first stage, two mixed integer-programming model is presented here that aims to minimize delay cost of air traffic. The first presented model seeks to minimize flights delay costs by choosing an optimal airport configuration and balancing departure and arrival flights and the second presented model solve this problem with the new approach with categorizing the airplane by types and prioritizing them. Numerical examples are solved in CPLEX 12.6 to evaluate models performance. Numeric... 

external radiation therapy is a methods of cancer treatment or improvement of cancer-related complications. various techniques have been developed for external beam radiation therapy. Among which, Intensity Modulated Radiation Therapy (IMRT), due to its ability to adjust the intensity of radiation beams, has a higher capacity to generate appropriate dose distribution based on tumor size and volume. Intensity Modulated Radiation Therapy is one of the most commonly used procedures of delivering radiation to cancerous tissues, with the aim of reaching the prescripted dose in the target volume while minimizing damage to nearby healthy organs. Two decisions are of fundamental importance: to... 

In this article we have investigated an inventory control model with uncertainly in supply and capacity constraints in the volume and variety of goods for supply chain of chain toy stores. The purpose of model is to minimize inventory costs, ordering cost and the cost of shortage to develop an acceptable customer service level. In order to execute replenishment process of goods we propose three periodic review inventory control policies that are implemented automatic, step by step and by using indicators defined in this article. The major difference between the proposed policies and the as-is policy is to use categorization od goods based on specific characteristics. Each of the three... 

Today the environmental management with an emphasis on environmental protection has become one of the most important issues of our customers, governments, industry and competitors and the global and international pressures require the organizations to produce environmentally friendly products and services. This challenge led to the creation of a new concept known as green supply chain management in business areas which is a combination of environmental and supply chain thinking. The aim of this study was to evaluate the performance of green supply chain management using SCOR model and offered suggestions for its improvement and the hypothesis of the proper performance of supply chain... 

Knowing different groups of customers and building effective communication with them in such a way as to guarantee the future economic interests of the organization is a very important issue in today's businesses. The attraction of profitable customers, as well as the preservation of valuable old customers, are both important, except for the precise identification of their features. The value of customer longevity plays an important role in customer segmentation, and there are numerous researches that focuses on customer value with the aim of making more profit for the organization, most of which have life-cycle customer value models as the main inputs for segmentation cCustomers have been... 

The aim of Emergency Medical Services (EMS) is to provide fast medical care and to transport patients to hospitals at the earliest possible time, so as to reduce injury and fatality rate. Healthcare managers try to improve healthcare systems by reducing the response time to demands. In this thesis, we present mathematical models for the problem of location and relocation of emergency vehicles after the end of their service time or after they have returned to a hospital. We believe that implementing these models can help managers improve the performance of emergency medical services. In the first part of this study, we present a two-level deterministic optimization model considering demand... 

Operating rooms have always been the most expensive and also the most profitable section in hospitals which include approximately one third of cost and two third of income. The management always wants to decrease the cost of hospitals. On the other hand, usually this goal stands against other goals such as patient’s satisfaction. So the manager should make a balance between these goals. In this research, we will propose an integer programming model for operating room scheduling problem without uncertainty for elective patients. In order to make the model more realistic, we want to make connection between operating room theatre and intensive care units. Also, we will consider desirable... 

At the present, End-stage renal disease(ESRD) is the ninth-leading cause of death in the USA.according methods of medical treatment for End-stage renal disease (ESRD), transplantation is the most viable renal replacement therapy for ESRD patients, there is a disparity between the demand for kidneys for transplantion and the supply. Incompatible inblood-type and antigen matching between patient-donor pairs is cause of shortage in disparity between the demand and the supply.paired kidney exchange of kidney among incompatible patient-donor pairs.PKE can be solve many difficulties in matching patient with incompatible donors. Kidney transplant surgeries in PKE must take place simultaneously... 

Cancer is one of the main causes of death among all people around the world. This shows that more and more attention should be paid to cure cancer. One of the most common cancer treatments is radiation therapy. Among all radiation therapy treatments, Intensity-Modulated Radiation Therapy is a very effective and flexible ways to treat cancer. There are numerous mathematical problems to find the perfect treatment plan. One of these mathematical problems is Fluence Map Optimization in which we try to find the best dose intensity for each tumor and surrounding organs. The main purpose in this problem is to minimize the number of cancerous cells which are being destroyed while minimizing the... 

As a method of cancer treatment or improvement of cancer-related complications, external radiation therapy is prescribed by physicians, in case of detection of a tumor in a region of patient’s body. Over time, various techniques have been developed for external beam radiation therapy. Among which, Intensity Modulated Radiation Therapy (IMRT), due to its ability to adjust the intensity of radiation beams, has a higher capacity to generate appropriate dose distribution based on tumor size and volume and it is one of the most widely used techniques in cancer treatment centers.The core process in treatment planning is using appropriate computer algorithms which results in posing enough damage to... 

Infectious diseases have always threatened the health of human beings. One of the most important causes of mortality in human societies is infectious diseases. The spread of these diseases in society, even if does not lead to death, can have devastating effects on society. Influenza is one of the infectious diseases that has attracted much attention today. It can be mild or severe and even cause hospitalization and death. Therefore, controlling and preventing the epidemic of this disease is very important. Epidemic models are commonly used to simulate the spread of infectious diseases. In this study to identify the influenza outbreak, a stochastic multigroup SEIR model with the migration... 

Nowadays, radiation therapy is one of the most common methods for the cancer treatment. Intensity Modulated Radiation Therapy(IMRT) is a novel technique of radiation therapy that aims to delivere sufficient dose to cancerous tissues while sparing healthy organs. There are various uncertainties in radiation therapy problems, including uncertainty about device setup, device errors, interfraction and intrafraction motions. One of the most important uncertainties is the movement of the tumor during the treatment process(intrafraction motion), as this displacement may cause the cancer tissue to not receive sufficient dose and also to damage the healthy tissue due to a violation of their dose... 

Nowadays, chemotherapy is one of the common ways to treat cancer. Although, chemotherapy is used to kill cancer cells , chemotherapy drugs also target healthy cells and tissues of the body. In practice, it is difficult to strike a balance between injectable doses of drugs and toxicity in the body, and physicians are always looking for an effective treatment plan. One of the most common drugs that physicians use in chemotherapy is cell-cycle-specific drugs. These types of chemotherapy drugs affect only a certain phase of cell cycle and to a certain extent. Since the lifetime of the cancer cells is uncertain, the effective use of these drugs depends on the correct injection time of the drugs... 

Home health care is one of the newest methods of providing services to patients in developed societies that can respond to the individual lifestyle of the modern age and increase of life expectancy. In this study, a new mathematical model is developed taking into account the flexibility of starting and ending locations of each nurse, according to the specific requirements of each service. In this context, there are some special services that require the picking of materials and health equipment from laboratory or force the nurse to return to laboratory to deliver the specimens and equipment. In the next step, this model is expanded to downgrading aspects by adding the objective of minimizing... 

Inside an airport, proper Ground Handling Operations (GHO) plays a significant role in timely airplane departures as well as reducing operating costs. These operations consist of numerous processes that follow standard precedence to avoid delays. In this research, the issue of scheduling and allocation of resources for ground operations of the airport has been investigated. For this purpose, using a mathematical programming approach, a two-objective model was proposed to reduce delays and costs. In this model, all ground operation equipment were considered integrally under the standard operational precedence. Moreover, due to the uncertainty factor in the problem under study, an interval... 

In recent two decades, occurrence of unexpected disruptions, made supply chains more vulnerable and caused huge damages to them. As a result, in recent researches, the concept of supply chain resilience that concentrates on supply chain vulnerability and disruptions has been focused more. In this thesis, a new framework for resilient suppliers characteristics would be presented that can be used for evaluating resilience level of suppliers and resilient supplier selection. By utilizing scenario-based two-stage stochastic approach, a multi-objective mixed integer nonlinear model is proposed for designing a resilient four echelon supply. In the proposed model, the possibility of partial...