Sharif Digital Repository

The goal of this project was study on coordination behavior of the 14-membered macrocyclic ligand of type N2O2 aza-crown while it is attached to fullerene C60 nano-particle. For this purpose, firstly the macrocyclic ligand (Fig 3-1, L1) was synthesized and then was reacted with C60 (Fig 3-1, L2) of which the product was characterized by elemental analysis. Since the product was insoluble in any solvents, further study on its coordination chemistry was impossible. In a second procedure, the macrocyclic ligand was reacted with benzylbromide. The reaction mixture gave two macrocyclic ligands with different number of benzylic pendant groups (Fig 3-1, L3-L4). The products were separated by column... 

Agriculture accounts for 70% of global freshwater consumption. However, precise data on irrigation water use (IWU) at the regional scale is often lacking, which hampers the development of effective water management plans. This study aims to estimate irrigation water use (IWU) by integrating remote sensing soil moisture (SM) and actual evapotranspiration (ET) data into a root-zone soil water model. Since irrigation influences both SM and actual ET, increases in SM and ET following irrigation events can be leveraged to frequently retrieve IWU from remotely sensed data. In this regard, we first developed an irrigation-free soil water model simulating root-zone SM dynamics during non-growing... 

Based on the importance of DNA/RNA binding proteins in different cellular processes, finding binding sites of them play crucial role in many applications, like designing drug/vaccine, designing protein, and cancer control. Many studies target this issue and try to improve the prediction accuracy with three strategies: complex neural-network structures, various types of inputs, and ML methods to extract input features. But due to the growing volume of sequences, these methods face serious processing challenges. So, this paper presents KDeep, based on CNN-LSTM and the primary form of DNA/RNA sequences as input. As the key feature improving the prediction accuracy, we propose a new encoding... 

Due to the data centers rapid growth and introduction of a new basic type of massive data processing platforms which requires accelerators to speedup computation and enhance the efficiency and reduce power consumption, using accelerators is inevitable. Communication and data transfer time between software and hardware is the most of time spent on the use of accelerators. By optimizing this part of the hardware / software platform, we have achieved substantial results in this area. The aim of our study is to organize a survey of real accelerator characteristics. To figure out its defects and main drawbacks, in addition to improving the overall efficiency of system. The implementation of... 

Coverage rate is a critical criterion in all of communication networks. In this regard, there are many different methods for distribution of network particles duo to attain the most efficient region of coverage. This emerges from the limited ability of each networks particle both in range of communicate and power consumption. In this thesis an evolutionary method is introduced to how Wireless Sensor Networks (WSN) particles can be dispensed to have more reliable coverage rate. Using both static and mobile sensor packages to cover the desired area and used a cost function, coverage rate, the authors tried to maximize it to have an excellent performance of network. Then proposed algorithm is... 

Speech synthesis and its applications have been very attractive recently. The main purpose of this technique is to produce a speech signal with natural characteristics of human speech like prosody and emotion. Among all existing methods for speech synthesis, statistical parametric speech synthesis methods are more promising because ofhigher flexibility in comparison to other methods. One of the applications of speech synthesis is speech to speech translation. In these systems, the generated voice in target language should have the same characteristics as the input voice in source language. The main purpose of this research is to review and evaluate the cross lingual speaker adaptation... 

Surface piercing propellers are particular type of supercavitating propellers that are commonly used for High-speed vessels. Most studies on this type of propellers has been investigating the hydrodynamic forces. But in recent years with increase in SPPs diameter used in vessels, structural analysis of this type of propellers is considered. For this purpose, studies on the stresses exerted on the propeller structures under load is done with the help of Hydro elastic methods. In this type of analysis, structura of propeller is intended to be flexible and Displacements under pressure checked and Tensions resulting from it are studied.
The present Thesis using ANSYS software to analyze a... 

Pricing plays an important and essential role in the profit and income of companies. The importance of pricing is not only related to its role in the company's profitability, but it also changes the customer's understanding and loyalty towards the company and can create the company's reputation or destroy it. Determining the right price will increase product sales and increase customer loyalty and create a competitive advantage for the company. One of the most important and influential variables in product pricing is the amount of demand. The main challenge of companies for product pricing is the uncertainty in their demand. In order to deal with this problem, data-driven pricing is used.... 

The increasing demand for autonomous vehicles and reliable communication protocols and hardware interfaces, such as CAN bus and USB, underscores the necessity for stable clock sources that maintain a low temperature coefficient (TC) over wide temperature ranges. This demand is particularly emphasized in applications such as wearables, network sensors, downhole devices, WSNs, and IoT, where long-lasting battery life and frequency-stable clock sources over a broad temperature range (e.g. -20 °C to 100 °C) are crucial. Traditionally, variations in frequency caused by temperature have been mitigated by employing off-chip components like crystals or ceramic based oscillators, but this approach... 

The increasing demand for communication bandwidth and limited spectrum availability have heightened the complexity of radio front-end circuits in IoT applications. Achieving spectral efficiency is a key challenge, particularly for IoT devices operating at specific frequency bands such as 315 MHz, 433 MHz, 868 MHz, and 915 MHz.Due to the limited linearity of the transmit path, harmonic distortion components, known as counter intermodulation (CIM) products, are generated. These CIM products can directly fall into the receiver (RX) band or enter it via cross-modulation, thereby degrading the frequency division performance. Additionally, CIM products can interfere with protected bands, violating... 

Ray-tracing method is extensively used for wave propagation analysis of indoor and outdoor environment for narrowband systems. The main goal of this research is to extend ray-tracing method for site-specific modeling of wideband electromagnetic propagation. In this thesis, Time-domain reflection and transmission coefficients have been computed for dielectric half-space and dielectric slab with frequency dependent permittivity. First, analytical form of Fresnel reflection coefficient for vertical and parallel polarizations in time-domain have been computed for dispersive half-spaces with lossy, extended Debye, two-pole Debye and multi-pole Debye models. By using these time-domain... 

Autonomous vehicles, as an integral part of intelligent transportation systems, will play a significant role in the future of transportation services. These vehicles have a high potential to improve road traffic capacity and the efficiency of transportation systems. One type of autonomous vehicle is the connected and autonomous vehicle (CAV), which can communicate with each other, roadside units, traffic control signals, and other infrastructures or devices. This study investigates the impact of autonomous vehicles and connected and autonomous vehicles on the traffic flow of the Tehran-Karaj freeway and vice versa, under various penetration rates and in a mixed traffic environment. In this... 

In the current situation and considering the economic conditions, entrepreneurship and self-employment are important factors of business growth. To prepare people in this field, there is a need for effective training that can motivate people. Identifying the effective methods and different dimensions of the entrepreneurship education framework that can lead to setting up a successful program for training people and facilitate the way to achieve the goal of education is one of the important goals of this research. By studying the literature from 2010 onwards, this research systematically examined 96 articles and tried to improve the framework of entrepreneurship education that was stated in... 

Research on the characteristics of the near field earthquakes has been very popular in recent years due to the considerable damages they have caused to the structures located within the vicinity of seismic sources. The incapability of response spectra for structural damage assessment has been revealed through recent investigations. The recorded data show that the near field earthquakes are often accompanied by a large energy pulse in the beginning of the records caused by the so-called directivity phenomenon. That has encouraged many researchers to study the possibility of using the velocity pulse of these records to evaluate the imposed seismic demands on structures. Thus, investigating the... 

Considering the widespread applications of amides, synthesis of these compounds is of great importance. The one pot oxidative addition of amines to aldehydes is one of the most simple and appealing approaches to synthesis amides. With the aim of developing a mild and convenient approach towards preparation of amides, numerous methods have been reported for this important process over the past few decades. These improvements have been mostly related to the optimization of reaction conditions and the use of more challenging substrates including diverse derivatives of aldehydes, and also design a novel and effective catalytic systems. Due to the various advantages of supported heterogeneous...