Sharif Digital Repository

Antioxidants are compounds which prevent free radicals from aggregation and formation in body cells. vitamin C, E and carotene are among the most important antioxidant that have reduction properties. free radicals have great chemical reactivity which can react with different types of compound in human body such as lipids, cell membrane and proteins and cause different illnesses. Antioxidants with various mechanisms such as hydrogen atom transfer, single electron transfer SPLET, sequential proton loss electron transfer and radical adduct formation can stable free radicals and also become non-active compounds, antioxidant properties of these compounds related to structure and their functional... 

The human action recognition is one of the most important concepts of computer vision in recent decades. Most of the two dimensional methods in this field are facing serious challenges such as occlusion and missing the third dimension of data. Development of depth sensors has made easy access to tracking people and 3D positions of human body joints. This Thesis proposes a new method of action recognition that utilizes the position of joints obtained by Kinect sensor. The learning stage uses Fisher Linear Discriminant Analysis (LDA) to construct discriminant feature space. Two types of distances, i.e., Euclidean and Mahalanobis, are used for recognizing the states. Also, Hidden Markov Model... 

The non-stationary nature of brain activity signals and their many inter-subject differences have created many challenges in the practical applications of emotion recognition based on electroencephalogram (EEG) signals, such as brain-computer interfaces. In such a way, the use of traditional classifiers in classifying these signals leads to a significant decrease in accuracy when applying the classifier to a new subject. Domain Adaptation methods seem to be an effective way to solve this problem by minimizing the difference between the EEG signals of different subjects. But in the basic techniques for domain adaptation, looking at all subjects' data in the same look causes the loss of a part... 

In this project, a novel action recognition method, named Fisherposes, is proposed, which is improved by several space-time (spatio-temporal) methods afterwards. The proposed method utilizes skeleton data obtained from Kinect sensor. First, pre-processing is performed in which the scales of bodies are canceled and the skeletons become aligned in order to make the method robust to location, orientation, and scale of people. In Fisherposes method, every action is defined as a sequence of body poses. Using the training samples for the poses, a Fisher subspace is created which we name it Fisherposes. Moreover, a novel distance measuring function, named regularized Mahalanobis distance, is... 

In recent years, displacement is more considered in comparison with force in design of structures. For example in 2800 standard -3rd edition- it is stated that for the reason that real displacement of structure in linear analysis is not calculable; it is necessary to resonate the lateral displacement of elastic analysis with a coefficient which is related to behavior coefficient of structure. This displacement should be less than allowable limit that is noted in the code. In similar foreign codes importance factor is also noted beside behavior factor in calculation of real lateral displacement of structure. Evaluation of this coefficient for different structures, comparison with suggested... 

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... 

Brain states analysis during consciousness is emerging research in brain-computer interface(BCI). Emotion recognition can be applied to learn brain states and stages of neural activities. Therefore, emotion recognition is crucial to the analysis of brain functioning. Electrical signals such as electroencephalogram (EEG), electrocardiogram (ECG) and functional magnetic resonance imaging(fMRI) are frequently used in emotion recognition researches. Convenience in recording, non-invasive nature and high temporal resolution are the factors that have made EEG popular in brain researches. EEG can be used to identify brain region activity solely or the connectivity of various regions in time in the... 

VLSI technology scaling has resulted in the integration of a larger number of cores in a single chip in successive technology nodes, offering a great potential to realize task-level redundancy for reliability enhancement in safety-critical applications. However, since battery technology no longer advances commensurately with integration density, multi-core platforms may have limited utility in battery-powered embedded systems. In this thesis, we propose an energy-budget-aware reliability management (enBudRM) method for multi-core embedded systems featuring hybrid energy source (with renewable and non-renewable energy sources). Our method is composed of two phases. In the offline phase, we... 

The synthesis, characterization, structural and computational studies of mononuclear Re(I) tricarbonyl complexes of 2,2'-bipyridine (2,2′-bpy) and 2,9-dimethylphenanthtroline (2,9-Me2Phen), [Re(CO)3(NN)(X)], where NN=2,2′-bpy,X=Br (1) and X=–ONO (3); NN=2,9-Me2 Phen, X=Br (2) and X= –ONO (4), were reported. The complexes characterized by crystallographic and spectroscopic methods and elemental analyses. In each complex, the Re(I) center showed the distorted octahedral geometry. Single crystal X-ray diffraction data revealed the endo-nitrito (κ1–ONO) coordination in complexes 3 and 4. It has been shown that the replacement of the bromo ligand in complexes 1 and 2, either by AgOTf/NaNO2 in a... 

The goal of this research is to convert letter to phoneme using deep neural networks. As the deep neural networks are among the best methods for speech and text processing (The highest accuracy in converting text to letter in English language is obtained by using deep neural networks too.), multilayer deep neural networks are used in this research to increase the accuracy. It should be noted that deep neural networks have not been used for converting text to phoneme in Persian language before. In this research a rule based alignment method based on our preposed rule is presented and achieved an accuracy more than 98%. Several approaches for converting word to grapheme with emphasis on the... 

Three-dimensional network-on-chip (3D NoC), the combination of NoC and die-stacking 3D IC technology, is motivated to achieve lower latency, lower power consumption, and higher network bandwidth. 3D NoCs reduce length of communication link and transmition delay by die stacking. However, the length of heat conduction path and power density per unit area increase as more dies are stacked vertically. High temperature results in longer propagation delay and increases the leakage power. If heat production in the chip is not managed, low cooling rate for these layers is a threat for the chip performance and reliability. To solve the thermal problems, thermal management schemes were proposed in the... 

In this project three models addressed before in the references are reviewed and the stability margins of radome error slope obtained by analytical method. Then a new model who is usefull in practical applications presented. Because of complication of this model the model is simplified and stability margins for radome error slope derived in simplified model. It is also shown that simplified applicative model is similar to model purposed in ref. [6]. Then a PD controller designed to stabilize some of models reviewed in chapter 3. The equations derived before verified in continuation of the project. The effects of parameters on the stability of missile analysed by equations derived in chapter... 

Plasma Electrolytic oxidation has recently been known as a new technology in surface engineering. It is one of the low-cost techniques used for improving corrosion and wear resistance in Al-Mg alloys. The purpose of this study first is to attach aluminum and magnesium alloys safely and without any defects, and then finding the optimum coating condition in connection line to achieve most possible corrosion resistance. For this purpose, first of all optimization of Al-Mg alloys friction stir welding (FSW) condition is required. After required investigations, it was shown that the weld created between Aluminum and Magnesium sheets by the cylindrical pin moving in a rotational speed of 550... 

The advancement of Cyber-physical Systems (CPSs) has attracted attention to Mixed-Criticality Systems (MCSs), both in research and industrial designs. Mixed-criticality systems (MCSs) integrate different types of functionalities with varying levels of criticality onto the shared computing platform. The scheduling algorithms for MCSs must guarantee that all high criticality tasks are completed by their deadlines in different operation modes of the system. In addition to certification, as multi-core platforms are becoming a dominant trend in designing MCSs, simultaneous energy and reliability management, and Quality of Service (QoS) are other significant challenges in designing MCSs. Indeed,...