Sharif Digital Repository

In practice, to implement Federated learning on edge networks, devices must repeatedly transmit their trained models to the edge server through wireless links to update the global model; Due to the heterogeneity in the Federated Edge learning system, such as lack of power, some devices may not be able to connect to the base station and reduce the performance of the trained model or, if connected, impose a large delay on the learning process. To overcome the mentioned challenge, we propose a Collaborative Federated learning framework. In this framework, some devices can participate in Federated learning without connecting to the base station; In this way, devices that are not able to... 

Increasing the complexity of software systems, their ubiquitous presence in the human activities, and necessity to preserving the functional and nonfunctional requirements of the systems under an uncertain environment, increase the need for self-adaptive systems. A self-adaptive system changes its structure and behaviors in response to changes in its environment and the system itself. A key research challenge in the self-adaptive community is to guarantee that the system fulfills its requirements. This issue can be addressed by employing formal methods during the design of the software systems. However, the assurance techniques should be used during the execution of the system as well as the... 

Objective: Stability is important to prevent falls during occupational and daily living activities. Control parameters such as speed, direction of motion and external load can affect stability pattern. The purpose of this study was to evaluate the effect of the mentioned control parameters on stability control pattern.
Methods: Kinematic data (rotation angles) to 19 healthy volunteers and 19 patients with low back pain associated with repeated trunk bending motion in eight different conditions of speed (high and slow), direction (symmetric and asymmetric planes) and external load (with and without load), was evaluated. Since the volunteers do during dynamic movements, they must also be... 

Loosening of uncemented tibial component is one the most common causes of total knee prosthesis failure which is a result of short-term factors such as instability and incomplete osseointegration as well as long-term factors such as peri-prosthetic stress shielding and bone atrophy. Porous cellular structures for tibial stem have been considered as a solution to this problem. This project is aimed to achieve an optimal gradient porous cellular design of tibial stem that in addition to sufficient mechanical strength, provides a perfect osseointegration and prevents bone resorption by incorporating appropriate porosity size, small micro-motion and favorable stress distribution on bone. A... 

Signal transmission of information on noiseless and lossy channels is an important issue in data transmission. Using the amplifier in the transmission channels is a good solution to help send information on longer channels. In classical communication, information can be coded in the amplitude or phase of the field and an amplifier is responsible for amplifying these parameters. If we consider the conditions ideal and ignore electrical noises, Classical mechanics does not impose any restrictions on the amplification of arbitrary classical signals. Instead, in quantum telecommunications the information encoded on the quadrature of the electromagnetic field are mounted on quantum states, such... 

Network Function Virtualization (NFV) is a new paradigm in computer networks for implementing network functions on general-purpose common-of-the-shelf processors. The revolutionized NFV architecture has shown to be a suitable replacement for hardware middleboxes. NFV is in high demand because of its lower costs, increased flexibility, and more scalability. However, the ever-growing volume of network traffic and increased data transfer speed in computer networks have made achieving high performance the major issue in this area. With thousands of processing cores and high memory bandwidth, Graphical Processing Units (GPUs) are potentially an appropriate solution to accelerate network... 

In recent years, the use of various catalysts has become a powerful tool in the synthesis of a wide range of biologically important molecules and or natural products toward the formation of carbon-carbon and carbon-heteroatom bonds. In the first section, the synthesis of magnetic catalyst based on acrylonitrile was reported and an attempt was made to use an efficient support and ligand to immobilize copper metals. Then, its structure was characterized by different techniques. The catalytic activity of the prepared catalyst was confirmed in the formation of indolyl diketones and the desired products were successfully synthesized with good to excellent yields. In addition, the catalyst could...