Sharif Digital Repository

The growth of user traffic and appearance of new services, has changed architecture of mobile networks. Data flows have different requirments based on their services. Mobile platform should be able to recognize services and slice network resources based on them. Different approaches have been investigated using relevant standards and numerous articles. The focus of this thesis is on implement a platform based on fourth generation mobile networks that can differentiate between data flows according to their respective required QoS.We have implemented an IMS network and connected it to a mobile core network But IMS network just supports session-based services. We introduced a solution for non... 

Power amplifiers are used as the last block of transmitters. This block can be categorized as the one of most important part in communication systems. However, in transmitter systems which require high power to create stable link with the receivers, fabrication process like CMOS are unable to provide such level of power. Thus, designers employ another group of integrated circuits which names MMIC that offers this capability to designers. MMIC is the abbreviation of Microwave Integrated Circuit which is implemented in compound substrates like GaAs. Monolithic microwave integrated circuits enable the implementation of amplifiers in small size, large number, with high precision and appropriate... 

The intrinsic properties of Mobile Ad-hoc Networks (MANETs) caused many challenges for these networks. Among these challenges, security is the most important one. Cryptography has many applications as a network securing method. Limitations on memory and processing capability of nodes in an Ad-hoc network makes it almost impossible to use common cryptography algorithms for these networks. Key distribution is the main challenge of cryptography; therefore, it is reasonable to simply the problem of cryptography in an Ad-hoc network to the problem of key distribution. Up to now, different methods are proposed for key distribution in MANETs; each of which has their own weaknesses. For example some... 

Execution speed seriously bothers application developers and users for wearable devices such as Google Glass. Intensive applications like Mobile Augmented Reality (MAR) suffer from significant delays when CPU is busy. Energy is another concern when the devices are in low battery level but users need them for urgency use. To ease such pains, one approach is to expand the computational power by cloud offloading. This paradigm works well when the available Internet access has enough bandwidth. Another way, however, is to leverage nearby devices for computation offloading, which is known as device-to-device (D2D) offloading. In this paper, we present Dandelion, a unified code offloading system... 

Due to the advantages of multi-agent systems, research in this area and the use of these systems in industry are increasingly growing. Applying these robots, various complex tasks can be done faster, safer and with better results. In our country, many different algorithms have been proposed and simulated, but due to the lack of a real environment for implementation, their actual performance has not been assessed. This project aims to create a platform for research and development of this field. This goal is achieved by performing the first phase of implementation, namely the design and construction of the robot platform. In the first step, qualitative and quantitative characteristics of the... 

In this research, we delve into the challenges video game developers encounter when selecting an appropriate genre for their initial video games. The primary objective of this study is to identify the effective strategies enabling video game developers to successfully enter the competitive market. Within this context, 'success' is quantified by sales volumes and download counts. The video game industry is witnessing rapid growth, with its market size reaching $184 billion in 2023, according to Newzoo report. To address these inquiries, the study uses information from three different platforms, gathering data in a thorough way: PC games on Steam, Android mobile games on the Google Play Store,... 

Natural selection in structured populations is considered a crucial subject in evolutionary and population genetics. There is no explicit relationship between discrete-time stochastic models such as the Moran process and continuous-time models such as the Fisher-Kolmogorov equation. However, under specific conditions and within the limits of natural selection and weak selection, a connection can be found between these two models. To gain a better understanding of the specific relationship between these two models, we obtain partial differential equations for the spatiotemporal dynamics of natural selection by extending the birthdeath and death-birth processes of the Moran process to a... 

Continuous Blood Pressure monitoring can provide invaluable information about individuals’ health conditions. However, BP is conventionally measured using inconvenient cuff-based instruments, which prevents continuous BP monitoring. This work presents an efficient algorithm, based on the Pulse Arrival Time (PAT), for the continuous and cuff-less estimation of the Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP), and Mean Arterial Pressure (MAP) values. The proposed framework estimates the BP values through processing vital signals and extracting two types of features, which are based on either physiological parameters or whole-based representation of vital signals. Finally, the... 

Recent studies show that spherical shape robots have been widely developed by many robotic researchers. A spherical shape can be also benefited in keeping mechanical components and electronic circuits inside a compact volume. The shell can also perform rolling motions for going fast and smooth on flat area. The reconfigurable spherical robot can be configured into a form of two interconnected hemispheres with three legs equipped with three Omni-directional wheels. The conceptual design of the robot will be initially packed and deployed in a spherical configuration. The spherical construction offers ease in transportation and deployment; for example, a number of these robots can be packed and... 

There has been growing interest in exploiting cellular network data for transportation planning purposes in recent years. In this thesis, we utilize these data for determining mode of travel in the city of Shiraz, Iran. Cellular data records -including location updates in 5minute time intervals- of 300,000 users from the city of Shiraz has been collected for 40 hours in three consecutive days in a cooperation with the major telecommunications service provider of the country. Depending on the density of mobile BTS’s in different zones of the city, the user location can be located within an average of 200 meters. Considering data filtering and smoothing, data preparation and converting them to... 

Nowadays, with the remarkable development of the robotics industry, there is an increasing demand for mobile robots. Mobile robots can be deployed individually or in groups for various tasks such as autonomous warehouses, search and rescue operations, firefighting operations, and maintenance and repairs. It is evident that performing certain tasks, such as moving large and long objects or firefighting operations, is more efficient when robots are deployed cooperatively, and in some cases, these tasks cannot be accomplished by a single robot alone. Therefore, in recent years, the issue of path planning for cooperative robots has received significant attention. By cooperation, we mean that... 

The emergence and development of E-commerce prompted many companies to reduce their cost by seeking new solutions that improve customer satisfaction level and product distribution. In this research, the coordination of a truck and a motorcycle is considered to utilize both vehicles' benefits. The mobile location of customers is another assumption in this research. Therefore, it is possible for customers to suggest different delivery times and locations. Based on the customer situation, there are three location modes which specify the accessibility. In this study, a mixed-integer linear programming model is presented to minimize service completion time. In addition, two metaheuristic... 

Mobile Bank is a service that has emerged for about a decadein Iran. while electronic methods and information technologies are used ininternational markets, in Iran using new technologies in the payment and financial industry is limited to the ATMs and Shetab network services. One of the mainreasons for the lack of tendency in using mobile banks and other electronic paymentmethods is these methods’ security concerns. Therefore, in this research, anattempt has been made to provide a model for technology acceptance in order toexamine the main factors of insecurity among users. As a case study, MellatMobile Bank's application has been evaluated in this research and an attempt hasbeen made to... 

Nowadays, swift development of cellular network with the increased penetration rate, have made mobile voice channels widely available almost everywhere with higher priority comparing to the other conventional channels, e.g., GPRS, EDGE, HSDPA and etc. Leveraging on this fact two important utilization can be considered. The first one is related to urgent transmitting of vital data. As mentioned earlier, since this channel deems to be available everywhere and, recalling its priority, it is even accessible in congestion condition, it can be exploited as an efficient way to transmit small volume of emergence data urgently. Transforming the crash data on the road is an example of utilizing such... 

In this thesis, the purpose of the research was to develop a four-wheeled Mobile platform (Lower body) with three degrees of freedom for a humanoid robot upper body which is called RASA. RASA robot was designed and constructed for helping kids who have speech and hearing impairments. The objective was to develop a low-cost and affordable robot as compared to its international models to be used at home or school as a teacher assistant. RASA can help kids to learn signs as fast as possible due to the game-based and entertaining education system. The wheeled base platform consists of a new mechanism with 6 bar linkage for bending robot from the hip to about 60 degrees from a vertical position... 

Automatic Speech Recognition (ASR) systems are a significant part of Personal Assistants in mobile phones. But because of the time-dependent nature of ASR systems, they are computation and memory-intensive tasks. On the other hand, mobile devices utilize a Low-Power design to extend battery life and improve user experience, making them incompatible with heavy-loaded tasks such as ASR systems. For instance, if we run an inference with a 60 seconds audio file on a well-known open-sourced Speech Recognition System named DeepSpeech, it will only take 49 seconds for a desktop PC to generate the results. Still, a mobile phone with ARM64 architecture with the same input file will take 92 seconds to... 

Vehicular Ad-Hoc Network (VANET) is a special case of Mobile Ad-Hoc Network (MANET) which is rapidly emerging with some unique properties in which vehicles have the ability to communicate with each other without any preexisting centralized infrastructure and coordinator. VANETs help in improving road safety, traffic control and information as well as commercial applications. Performance of such kind of communication between vehicles depends on various routing protocols. Routing may be a great thought employed in VANET. Current routing protocols cannot perform efficient routing in both high and low density of vehicles environments. Therefore, we propose a hybrid reliable routing protocol for... 

A Mobile Ad hoc NETwork (MANET) is a set of wireless mobile nodes that form a self configured network. MANETs do not have infrastructure and are not currently deployed on large scales. So research in this area is simulation based. Mobility model in a mobile ad hoc network explains the movement pattern of mobile users and is designed to describe the change of their location, velocity and acceleration over time. One of the challenges in this field is the definition of a common mobility model that provides an accurate and realistic movement description of mobile nodes. In this thesis we want to study the mobility pattern of vehicles on Kish Island and compare it with different kinds of... 

Nowadays, application of microwave integrated circuits in commerce and humanitarian military measures plays an important role. When integrated microwave circuits emerged, the dream of producing high quality and low cost amplifiers and mass productionhas been fulfilled. Power amplifiers which are the last block in a communication systemare one of the most important circuits in this field.
Since driver amplifiers are interstage between high and low power sections of a system, should have good specificationsfor both small and large signal analysis. Thus, designing such a circuit can be very challenging. In order to get the desired bandwidth, high-order filters are used as interstage... 

Hybrid mobile applications combine the features of Web technologies and native mobile apps. Like Web applications, they are implemented in portable, platform independent languages such as HTML and JavaScript. Like native apps, they have direct access to local device resources. In these programs, web contents are loaded into a web component, called WebView, which can render HTML5 pages and execute JavaScript code. In order for the web content to access the system resources, which are isolated from the content inside Web-View due to its sandbox, bridges need to be built between JavaScript and the native code. developers usually use third party plug-ins for native side of application. hybrid...