Sharif Digital Repository

This thesis is related to applying survey of scientific inventory control methods in Khoramshahr Oil Extraction Company (KHOEC). KHOEC is the producer of edible oils in I.R of Iran and is a subset of E.T.K.A holding organization. The inventory costs of high consuming items are studied and optimized based on the optimal ordering policy (r, Q). First, the company raw materials are identified and classified based on ABC analysis method. For developing the new method of inventory control, the demand for each item is predicted, and the probability distribution of demand during the lead time is determined. Then according to this information and the desired service level of management, order point... 

The main factor ensuring safety of passing maneuvers on two lane highways is known as Passing Sight Distance (PSD). The criteria presented in Iran's code and AASHTO Green book are provided by the results of researches conducted between years 1938 & 1941 in the United States. This research intends to find out whether some changes should be applied to the PSD criteria according to current vehicles' performance and driving behavior in Iran. For this purpose, about 8 hours of video films has been recorded from 3 different sites chosen from two-lane highways in Iran, resulted in 326 passing records. In the case of passing of two passenger cars The models provided by analyzing the videos show that... 

A Balanced Scorecard (BSC) model is proposed to evaluate performance of Health, Safety and Environment (HSE) management systems. This model includes key performance indicators at three integrated levels. It has been tested and verified in a project-based organization in Iran, active in the area of power and energy. Results show that the company has done well in implementing HSE management processes, but no so well in growth and learning. This model may be used as a basis for comparing different companies and various proposed programs in the field of HSE management systems. The model includes indicators and sub-indicators in each category particularly related to stakeholders, processes, and... 

Competitive world of industrial production need more speed and faster reaction for the customer needs. This should be carried out in low cost activities while satisfying what the consumers and customers require. Business of commercial refrigerators and freezers is a big industry targeting small to big customers. In this thesis a systematic method relying on reduction of cost, reworking and unexpected expenditures in product life is utilized. Stands for Design for Manufacturing, DFM is a series of principles and guideline simply to achieve a faultless design of a product so that the non-incurred costs of the product travel through its life cycle become minimized. Freezers and refrigerators... 

In this thesis, a complete analysis of a general within-host models of malaria is done. This model generalizes the models in epidemiological literature. In this study, we propose another equation for immune effectors reaction. In this thesis, we find out that the global stability of disease free equilibrium is obtained when the reproduction number R0 < 1. When R0 ≥ 1, at least one endemic equilibrium exists. The local and global asymptotic stability is investigated. Finally, numerical simulations are done to illustrate the influence of immune effectors reaction  

Identifying driving behaviors and building an efficient and accurate driving behavior recognition model is of paramount importance for improving driving safety. Nowadays, with the ubiquity of smartphone sensors, many researchers are using smartphone sensory data to create models which forecast driving behaviors. This research introduces a logit model that predicts nine types of driving events using accelerometer and gyroscope sensors with an accuracy of 76 percent  

In this study the modeling of Bushehr power plant containment is considered. In Bushehr atomic power plant, which has a unique design, the containment is similar to PWR power plants with a metal sphere, but the installed reactor is a VVER-1000. After a full study on the containment and its systems, the required date for modeling is gathered and afterwards, the engineering handbook is prepared for MELCOR input code and then the modeling and size classification of the containment is done in 4 different ways, including the control volumes of 1, 9, 23 and 30 and then the temperature, pressure and density of hydrogen is examined. The result of studying control volume sensitivity reveals that 23... 

Domino accidents are one types of incidents that lead to irreparable damage to industrial units. Since the consequences of such incidents are far more than the first level incident, consideration of this issue and the provision of appropriate strategies for identifying and evaluating this type of incident is very important. Major efforts have been made in the area of process safety is in risk assessment and identify possible scenarios and their probability of occurrence, and have not addressed the financial consequences of an incident. In this research, an algorithm has been developed to estimate the financial losses incurred with an industrial unit due to a domino incident and various... 

Emergency Shut Down systems are considered as one of the prominent protection layers in industries. In the situation that the process variables exist acceptable limits, the SIS brings the process in a safe state. According to standards, separate design and operation have been defined for BPCS and SIS. In this research, safety issues related to one of the gas refinery unit has been investigated. In fact, the unit does not have shut down system and all the safety loops are defined as DCS. In the first step, the Safety Integrated Levels of the loops which must be defined in shut down system have been specified by using Modified Calibrated Risk Graf. In next step, philosophy of shut down levels... 

This research is focused on domino accident risk assessment. Domino accidents are such events wherein one accident in a process unit becomes the cause of another (and at times yet another and still other) accident. Domino or knock-on accident is not an infrequent occurrence in process industries. In this research an inventory of the major process industry accidents involving ‘domino effect’ is presented. The inventory includes, among other relevant information, the sequence of accidents that had occurred in each domino episode. The information has been analyzed to identify several patterns which may be useful in further work on understanding domino effect and reducing the probability of its... 

Structural safety evaluation is an indispensable part of every post-disaster investigation, which should be conducted by inspection teams consisting of experienced structural engineers and trained inspectors. A complete evaluation takes up to three stages of assessment, to quantify and measure the magnitude of damage before proposing an overhaul resolution. According to the current codes of conduct, much of this complex and time-consuming process, especially in the first two stages, is left to the human judgment. To achieve a more uniform and in depth inspection, a new algorithm is presented to limit the arbitrary nature of the human opinion in damage evaluation, using properties of the... 

Despite eye-catching progressive trends in highway safety, there have been a great number of unpleasant incidents in highways. A number of 8841 people died in road accidents in the first 6 month this year with 1.7% increase compared to the accidents occurred in 1396 [59]. Operation of a modeling process shall provide the engineers with more opportunities to identify the affecting factors in roads incidents. Safety infrastructure management is mainly aimed at ensuring the efficient measurement, systematic recognition and consequently deterioration of road accidents when they have been designed, constructed and used [37]. Building information modeling (BIM) tends to be a developed managerial... 

Human error is one of the most important causes of accidents. Distraction and lack of attention to driving, fatigue, poor vision, speeding, and other such errors by drivers can cause accidents. With the rapid advancement of technology, transportation planners also thought of making cars as smart as possible to reduce human error. In this study, the effect of self-driving cars on the number of accidents at two unsignalized intersections is investigated using traffic microsimulation. For conventional vehicles, the factor considered for the simulation and calibration is driver distraction, which may be caused by reading or writing a text message on a cellphone or other items. This factor can be... 

Gas detection systems are now recognized as an essential component of safety in process units.but their successful performance depends strongly on the number and location of the detectors.As for the limited resources available (detectors), the placement of gas detectors can be considered as an optimization problem with different objective functions. In this research, an attempt was made to provide models and methods that quantitatively and from a practical point of view to optimum locate the detectors. Initially, a risk-based method was presented that defines the necessary steps for the arrangement of fire gas detectors with the aim of covering the maximum risk of leakage scenarios (risk:... 

Along with the emergence of the smart city concept and the increasing demand for a wide range of vehicles, the Internet of Vehicles (IoV) has attracted a lot of attention by providing numerous benefits including vehicle accident warning, reducing pollution levels and traffic congestion, as well as entertainment services. Furthermore, IoV offers various services combining Vehicular ad hoc networks (VANETs) and IoT in smart cities. However, these types of networks are exposed to a variety of security and privacy risks due to the wireless nature, because the sensitive message is transmitted through an insecure channel in the IoV-based smart city environment, therefore, it is necessary to... 

Traffic accidents around the world kill a large number of people every year, and their lightest consequences are temporary disabilities for citizens. According to the statistics, the number and severity of accidents have been growing, due to the expansion of cities and the human population there, and this increases the need to pay attention to traffic safety. One of the substantial subcategories of traffic safety research is public transportation. However, limited studies have been done in this field. One of the main modes of public transportation are buses, which bring more risk of accidents to passengers, due to their size and higher passenger capacity compared to passenger vehicles.... 

The construction is classified as a high-risk industry. The number of casualties and fatalities in this industry is disproportionately high. The ability to recognize hazards in the construction process and the design stage is still in its early stages of development. The most important way to control and eliminate hazards and accidents is to analyze these hazards before they occur and plan to deal with them before starting project activities. Identifying safety risks is the first step in evaluating and analyzing these risks. Building Information Modeling (BIM) technology, due to the consideration of the relationship between the elements in the model and because it contains an object-oriented... 

The utilization of tower cranes at construction sites presents numerous inherent risks. These cranes are commonly employed for lifting heavy loads, which carry the potential hazard of accidental falls. Simultaneously, workers may inadvertently overlook overhead dangers while focusing on their tasks. To mitigate these risks, laws in many countries explicitly prohibit individuals from occupying the vicinity directly beneath suspended loads, known as the fall zone. Such measures are vital to safeguard against the peril of heavy loads plummeting onto people. However, existing studies have not offered a comprehensive and efficient approach to identify crane load fall zone. To address this gap,... 

Among motorized vehicles, motorcycles are recognized as a common mode of transportation in countries with low to moderate income. Iran is also one of the countries where motorcycles are considered a primary means of transportation. However, in recent years, motorcycle accidents have sharply increased, with 30 percent of accidents in Iran involving motorcycles. This highlights the importance and necessity of taking measures to enhance safety and reduce motorcycle accidents in Iran. In this study, data on intercity motorcycle accidents in the provinces of Khorasan Razavi, Isfahan, Qom, Mazandaran, Gilan, Hamedan, Hormozgan, and Ilam were used. The main objective was to identify and compare the...