Sharif Digital Repository

The fast development of semiconductor industry has moved the design methodology to SoC (System on Chip) design. Due to the increasing number of processing elements, In SoC, buses become the bottleneck of the system and lead to non-efficient designs. NoC (Network onChip) is an efficient solution that eliminates bus bottleneck and it had been introduced as a suitable substructure for interconnecting processing elements. The NoCs were originally built based on Interconnection Networks.They have been proposed as an efficient, scalable, modular and reliable solution to provide on chip communication in any large SoC design. The trend of market to mobile digital systems and battery-powered devices,... 

This study focused on the tolerance of fungi strains including Aspergillus niger, Aspergillus foetidus and Penicillium for different metals (Ni, Co, Mo, V, Mn, Mg, Fe, W and Zn ). Then Aspergillus niger was exposed to mixture of Mo, V and Mn (at a mass ratio of 1:2:6 as approximately present in the spent refinery processing catalyst). The degree of tolerance was measured from the growth rate in the presence of various metals and compared to a control which contained no metals. Effect of type of strains, type of metal and metal concentration on adaptive tolerance of fungus was evaluated. Adaptation experiments with single metals showed Aspergillus niger tolerated up to 1000 mg/l Ni, Zn, 1500... 

Wireless sensor network (WSN) multimedia applications impose new challenges in the design of algorithms and communication protocols for sensor networks. Indeed, wireless multimedia sensor networks (WMSNs) must provide relatively high throughput and low end-to-end delay and jitter while being energy-efficient. In view of these challenges, error control is an important mechanism which enables us to provide robust and high quality multimedia communication in WSNs. In this thesis, we first perform a comprehensive performance evaluation of different error control schemes for multimedia communication over WSNs. The results of our analysis show how wireless channel errors can affect the performance... 

In this paper, controlling the cutting force of an end-milling process using a supervisory fuzzy controller has been investigated. The proposed control consists of an ordinary fuzzy controller and a fuzzy supervisor. In a machining process, there are several parameters which do not contribute to the force control system directly. Therefore an ordinary fuzzy force controller is suitable when these parameter have only small amount of variations. Since in practice this assumption is not valid, then a supervisory fuzzy controller has been added to the system. The designed fuzzy supervisor, inspects the dynamic behavior of the cutting force, estimates a pre-defined ‘sensitivity’ parameter and... 

Acidophilic microorganisms such as Thiobacillus ferrooxidans have the capability to carry out process of biorecovery of heavy metals. Its principle is the microbial production of the sulphuric acid and simultaneous recovery of metals. Acidithiobacillus ferrooxidans derives the energy for their metabolism from ferrous iron oxidation process which can be affected by the presence of heavy metals in the medium. In this study the ability of Acidithiobacillus ferrooxidans, on the biorecovery of heavy metals in shake flask has been investigated The adaptation of the Acidithiobacillus ferrooxidans to a kind of heavy metal such as Nickel, Cobalt, Vanadium, Molybdenum, Tungsten and the mixture of the... 

This thesis presents a general method for real-time adaptation of wireless receivers according to the prevailing reception conditions. In order to maintain the desired signal quality at the minimum possible power dissipation, the method performs an optimal trade-off between noise, linearity, and power consumption in the building blocks of the receiver. This is achieved by continuously monitoring the signal-to-noise plus interference ratio (SNIR) and accordingly tuning the adaptation parameters embedded in the receiver design. A prototype DVBH receiver chip, implemented in a standard 0.18-µm CMOS process, is used as the test vehicle. By properly trading noise with linearity in the receiver,... 

Accumulation of electronic wastes in the environment is one of the recent ecological problems. This type of wastes contain metallic and non-metallic elements which can contaminate the environment. On the other hand due to the high volume of precious and basic metals within e-waste, it could be considered as a secondary resource. Bioleaching is a suitable method for the recovery of metals from e-waste which, on the contrary to the conventional recycling methods in the industry, is both economically and ecologically efficient. The aim of this research is the isolation of native micro-organism and evaluating its ability in recovering copper from a mixture of computer, cellphone, fax and copy... 

The recycling of the secondary resources for the extraction of their metallic contents is undoubtedly environmentally friendly and can be economic. One of the most important secondary resources is the electronic wastes (E-wastes) which has been widely produced as the discarded electrical/electronic devices. The usual physical/chemical treatments of E-wastes not only result in an increase in human health risks and environmental pollution but also lead to the missing of their valuable metallic contents. An alternative method for the recycling of E-wastes is bioleaching which has recently attracted more attention. The advantages of this process are low energy consumption and environment... 

In this article, we will examine the theory of evolution through natural selection and we will show that the evidence in favor of natural selection is so great that today this theory has been fully accepted by the scientific community. The theory of evolution had many philosophical and theological consequences; One of its direct consequences was the weakening of teleological arguments and specifically the argument of William Paley's plan; Because in the light of this theory, the existence of features with functions and complex adaptations of living things can be explained without the need of designing a supernatural agent. Despite this, biology still uses concepts such as function, which has...