Design and Implementation of a CMOS Fractional-N Frequency Synthesizer for UHF RFID Readers

, M.Sc. Thesis Sharif University of Technology Moslehi Bajestan, Masoud (Author) ; Sharif Bakhtiar, Mehrdad (Supervisor)

Abstract

A 1.8-v 1.8-GHz fully integrated CMOS fractional-N frequency synthesizer is designed and tested for UHF RFID readers. The synthesizer employs a dual-loop architecture to realize a monolithic design with more optimal trade-off among phase noise, channel spacing, reference frequency and settling time compared to the conventional integer-N phase-locked-loop architecture. Due to the large self-interference and the backscatter scheme of the passive tags, reader synthesizer’s phase noise requirement is stringent to minimize the sensitivity degradation of the reader RX. A 1.8-GHz complementary VCO with noise filter has been used to achieve these tough specifications. Also, since a large KVCO can...

Heavy metal removal from water and wastewater using raw and modified diatomite

, Article International Journal of Engineering, Transactions B: Applications ; Volume 20, Issue 2 , 2007 , Pages 141-146 ; 1728-144X (ISSN) Moslehi, P ; Nahid, P ; Sharif University of Technology

Materials and Energy Research Center 2007

Abstract

Heavy metal removal from water and wastewater was investigated by using raw and modified diatomite from Iranian mines. Modification of diatomite was done by impregnating the diatomite surface with 0.35 g of manganese oxide in one gram of diatomite. This modified diatomite was named Mn-Diatomite. The surface area measurements for Mn-diatomite showed a 2.2 fold increase, hence higher removal capacity for the heavy metals. The results of the removal showed an increase in adsorption capacity which was for Pb2+ about 40 mg/g, for Ni 2+ about 34mg/g and for Cu2+ about 33mg/g. The filtration quality of diatomite was significantly enhanced with surface modification by manganese oxide

Treatment of Surfactant Wastewater by IFAS Bioreactors

, M.Sc. Thesis Sharif University of Technology Moradian, Amin (Author) ; Borgheei, Mahdi (Supervisor) ; Moslehi, Parivash (Supervisor)

Abstract

In the modern societies, wastewater treatment is essential in achieving high level of standard in environmental protection and disposal. Recently, many researches are performed to study the surfactants’ biological decomposition in wastewater treatment process. In this project, fixed bed aerobic reactors are used in order to remove surfactant from wastewater. Integrated fixed film activation sludge reactor (IFAS) is used to remove surfactants and organic matters. It also used to study the capability of micro organisms in organic load removal in fixed bed biofilm for biological treatment of industrial wastewater. Pumice stone were used as the support in the reactor. The pumice stone is a...

Two-machine flow shop scheduling to minimize the sum of maximum earliness and tardiness

, Article International Journal of Production Economics ; Volume 122, Issue 2 , 2009 , Pages 763-773 ; 09255273 (ISSN) Moslehi, G ; Mirzaee, M ; Vasei, M ; Modarres, M ; Azaron, A ; Sharif University of Technology

2009

Abstract

This paper presents optimal scheduling in a two-machine flow shop, in which the objective function is to minimize the sum of maximum earliness and tardiness (n/2/P/ETmax). Since this problem tries to minimize earliness and tardiness, the results can be useful for different production systems such as just in time (JIT). This objective function has already been considered for n jobs and m machines, but the proposed algorithms are not efficient to solve large scale problems. In this paper, neighborhood conditions are developed and the dominant set for any optimal solution is determined. The branch-and-bound (B&B) method is used to solve the problem and the proper upper and lower bounds are also...

, M.Sc. Thesis Sharif University of Technology Allah Yari, Mahdi (Author) ; Soltanieh, Mohammad (Supervisor) ; Moslehi Moslehabadi, Parivash (Supervisor)

Abstract

Air pollution caused by industrialization is the problem which adversely affects human life. Among air pollutants suspended particles, especially particles smaller than 10 microns (PM10), for their high concentration in air in large cities are the major index as air pollutant. Due to their small size, PM10 can penetrate into the aspiration organs causing harmful effects. The objective of this work is to develop an Artificial Neural Network (ANN) model for prediction of short-term concentration of PM10 in the city of Tehran. Complex mechanism of reactions, numerous types of pollutant materials produced from transportation and industrial activities, variety of sources, difficulties in data...

Upgrading Activated Sludge Study System by Introducing Moving Carriers

, M.Sc. Thesis Sharif University of Technology Mofidian, Maryam (Author) ; Borghei, Mehdi (Supervisor) ; Mosleh Abadi, Moslehi (Co-Advisor)

Abstract

In this study, the use of a fixed bed of the Kaldnes commercial carrier in the activated sludge system has been investigated. In this way, at zero time, a submerged fixed bed of Kaldnes was placed into a completely mixed activated sludge reactor and its various parameters were investigated during the time. During the experiment, the fixed bed (Kaldnes carriers enclosed in a lace) with 20, 35 and 50 percentage of volumes were compared to regular activated sludge reactors (without any carriers). The studied parameters are COD, DO, MLSS, and P-PO43-. Input COD was changed at concentrations of 1200 and 400 mg/L, and the reactor hydraulic time was adjusted to 10 and 16 hours. It was observed that...

Feasibility Study on the Production of Biodiesel Using Domestic Wastes

, M.Sc. Thesis Sharif University of Technology Atapour, Mehdi (Author) ; Kariminia, Hamid Reza (Supervisor) ; Moslehi, Parivash (Supervisor)

Abstract

Biodiesel as an alternative fuel for fossil diesel has many benefits such as reducing regulated air pollutants emissions, reducing greenhouse gases emissions, being renewable, biodegradable and non-toxic. In this study, used frying oil was used as a low cost feedstock for biodiesel production by alkali-catalyzed transesterification. The used frying oil was originally a mixture of various oils obtained from vegetables that are native to Iran. The design of experiments was performed using a 5-level-5-factor central composite design coupled with response surface methodology in order to study the effect of factors on the yield of biodiesel and optimizing the reaction conditions. The factors...

Biological Sludge Reduction in MBBR Process

, M.Sc. Thesis Sharif University of Technology Tahmasebian Dehkordi, Sepehr (Author) ; Borghei, Mehdi (Supervisor) ; Moslehi Moslehabadi, Parivash (Supervisor)

Abstract

Laboratory experiments were carried out to investigate the effect of ultrasound waves on sludge reduction in MBBR bioreactor for industrial wastewater. The experiments were performed using two identical 20L MBBR bioreactor under same operational conditions. In MBBR with return sludge, sludge was collected from clarifier and after being sonicated, returned to the system by pump.
For determining optimum intensity and time duration of ultrasound, 0.3lit of MBBR sludge was sonicated with intensities of 20, 30, 60, 120, 150, 250 w/cm2 and time duration of 5, 10, 15, 20, 30 min. Afterward, these two parameters were optimized with Energy Efficiency Index. As the results shown, intensity of 120...

Investigation of Petroleum Pollutant Removal in a Membrane Bioreactor

, M.Sc. Thesis Sharif University of Technology Rahmani Nezhad, Ali (Author) ; Kariminia, Hamid Reza (Supervisor) ; Moslehi Moslehabadi, Parivash (Supervisor)

Abstract

In this study, the performance of Convectional activated sludge reactor (CAS), moving bed biofilm reactor (MBBR) and coupled MBBR-membrane bioreactor (MBR) for diesel removal was investigated.
Hydrocarbon quantification was conducted based on a photometery method at 250 nm after extraction with n-hexane.
Experiments with MBBR was conducted in a batch mode using the sludge obtained from a municipal wastewater treatment plant. In order to adapt microorganisms with diesel as carbon sourse, diesel concentration was gradualy increased from 100 to 3400 ppm where diesel removal efficiency decreased from 62/1 to 26/6 %. However, after addition of diesel degrading bacteria (previously...

Long Term Effective Factors on House Price of Metropolises of Iran

, M.Sc. Thesis Sharif University of Technology Moeeni, Safoura (Author) ; Nili, Masoud (Supervisor)

Abstract

The notable share of housing sector in GDP (approximately five percent) shows this sector’s relation with macroeconomic activities. On the other hand, House as an asset leads housing sector to be affected by monetary and fiscal variables. A dynamic panel data was used in this study to evaluate the relations between housing sector and some macroeconomic variables in metropolises of Iran. As results show, in long term growth of liquidity, GDP per capita and sharp ratio have positive effects, and land per capita has negative effect on housing price in metropolises of Iran. Price increases have not been equal in different cities. Inequality of land price between metropolises and between...

Estimating an Index of Iran’s Informal Economy in 1350-1386 With Concentration on the Impact of Government’s Intervention by EMIMIC Model (The Multiple Indicators-Multiple Causes Model and Error-Correction Model)

, M.Sc. Thesis Sharif University of Technology Khandan, Abbas (Author) ; Nili, Masoud (Supervisor)

Abstract

In this research, an Index of Iran informal economy in response to the government interventions in credit, labor and product markets is stimated by EMIMIC model. To do this, first these interventions are measured using principal components analysis. In the model, the variables GDP and employment are used as indicators and taxation rates, government distortions in credit, labor and product markets, government expenditure, per capita income, unemployment and inflation as causes of the informal economy. We conclude these government interventions have affected Iran informal economy and their influence is more than indirect interventions influence such as taxation. The estimated index of Iran...

Water Quality Modeling of Urban Streams

, M.Sc. Thesis Sharif University of Technology Soltani, Maryam (Author) ; Tajrishy, Masoud (Supervisor)

Abstract

With altering natural state and increasing impervious surfaces, traditional urbanization leads to deteriorating the environment and water catchments. During the years most efforts in order to control the urban runoff outflow, have been focused on quantity; and awareness about improving water quality has been raised just in the last few years and, which emphasizes on pollution source control. Standard water quality sampling methods are time consuming, expensive and because of sampling in broad geographic areas, difficult; however modeling is a more efficient way in assessing water quality and as worries about non-point source pollution grows, different kinds of models have been used to...

The Political Economy Aspects of the Redistributive Role of Government in a General Equilibrium Micro-founded Macro Model

, M.Sc. Thesis Sharif University of Technology Zakeri, Hassan (Author) ; Nili, Masoud (Supervisor)

Abstract

The role of government in economy has been a controversial subject in economics. Lately, there has been some fundamental change in evaluating this subject. One could mention two of these as 1) realizing the importance of micro-founded macro model for evaluating policy, and 2) taking into consideration the rent-seeking behavior of politicians. In this research, a general equilibrium in a micro-founded macro model will be discussed and then in political economics framework, the effect of government on this equilibrium will be investigated. Only the redistribution role of government has been considered. First, the model in which a benevolent government is seeking optimal policy is Discussed....

Measurement of Gini Coefficients by Means of Household’s Special CPI in Iran(1984-2005)

, M.Sc. Thesis Sharif University of Technology Ghasemi, Mojtaba (Author) ; Nili, Masoud (Supervisor)

Abstract

Gini coefficient is the most prevalent index for the measurement of inequality and is usually extracted by means of nominal variables based on income or expenditures of households. In this study we have extracted more accurate Gini coefficients. By using the raw data of Households Budget Survey (HBS) and STATA software, a special CPI for each household of the sample is extracted. Subsequently nominal expenditures are deflated by these special CPIs, and at last, Gini coefficients are extracted from real expenditures. Our findings indicate that in recent years, extracted Gini coefficients are remarkably higher than prevailing ones.

Parametric Evaluation of the Y- Shaped Bracing Frame and Introducing a New Method for Design

, M.Sc. Thesis Sharif University of Technology Sedaghati, Parshan (Author) ; Mofid, Masoud (Supervisor)

Abstract

This paper investigates the behavior of the Y-shaped bracing system. Because of the special type of eccentricity in this system, the behavior of the frame is strongly dependent on the geometrical changes of the braces. So that even in the elastic region, it shows the geometrically nonlinear behavior. The amount of eccentricity is very effective on the nonlinear behavior of the frame. Also the ratio of cross sections of the bracing members has a very important impact on the expected performance of the frame. The results show that this system tolerates large displacements, and can act like a base isolation system. Firstly, using a two-dimensional accurate modeling related to the geometrical...

Assessment of Seismic Behavior Factor of Irregular Midrise Steel Structure

, M.Sc. Thesis Sharif University of Technology Baghi, Alireza (Author) ; Mofid, Masoud (Supervisor)

Abstract

The Overstrength, Ductility and the Response Modification Factor (R) for 70 steel X-braced , Inverted-V-Braced and Offcenter Bracing System frames were evaluated by performing pushover analysis of model structure with various stories (3,6,9,12&15 story) and span length (4,6&8 meter). Some result were compared with those from nonlinear dynamic analysis. According to the analysis result the R factors obtained from nonlinear dynamic analysis are 15% more than obtained from pushover analysis and R factors computed from pushover analysis were generally smaller than the values given in the design codes. R factors in Irregular structure in height are about 90% of R values in regular structure in...

Synthesis of γ-Fe2O3 Nanoparticles by Gelatin Mediator and Synthesis of γ-Fe2O3/SiO2/PCA/Ag-NPs Nanostructure Drug Delivery System

, M.Sc. Thesis Sharif University of Technology Masoud, Nazila (Author) ; Pourjavadi, Ali (Supervisor)

Abstract

Maghemite (γ-Fe2O3) nanoparticles were produced after high temperature oxidation of gelatin-Fe3O4 nanocomposite, obtained from a common coprecipitation process of Fe2+ and Fe3+ ions in an alkaline medium in the presence of a gelatin protein as an effective mediator. Size, shape, surface morphology and magnetic properties of the prepared γ-Fe2O3 nanoparticles were characterized using XRD, FTIR, TEM, SEM and VSM data. The results revealed that primary, gelatin-Fe3O4 nanocomposite had been formed and next, the gelatin decomposition in furnace produced a spinel structure of γ-Fe2O3. The effects of furnace temperature and time of heating together with the amount of gelatin on the produced...

On The Behavior of Low-Rise, Irregular, Dual Structures

, M.Sc. Thesis Sharif University of Technology Khazaei, Siamak (Author) ; Mofid, Masoud (Supervisor)

Abstract

The Response modification factor R represents the behavior of the structure such as ductility, overstrength and the inherent redundancy. This factor shall be defined according to the type of lateral force resisting system. However, there are some complexities and/or uncertainties in codes related to the R factor according to the height, form of irregularities and structural systems. Therefore, from the scientific point of view as well as reliability, it is very clear that the R factor cannot be similar for all kinds of structures, categorized as a specific group. In this investigation, assuming a low-rise, vertically irregular structure with a heliport which has a dual structural system...

Modeling Phosphorous Movement in Watersheds with SWAT (Case Study: Kan Watershed)

, M.Sc. Thesis Sharif University of Technology Delkash, Majid (Author) ; Tajrishy, Masoud (Supervisor)

Abstract

Maintaining the quality of water is of paramount importance for lakes with tourist attraction capacity. Inaccurate prediction of the quality state of lake in design phase may lead to some trouble in future. Kan River known as the main source of water feeding for the urban lake located in the north of Chitgar park passes through various villages and restaurants discharging nutrients via runoff and wastewater in the aforementioned river. Previous investigations reveal that phosphorous plays a central role in the water quality of this river and the associated downstream lake. In this research, Kan watershed,located in in the north-west of Tehran, was simulated. Considering the "Total Maximum...

The Role of Socio-Political Institutions in Economic Performance of Developing Countries

, M.Sc. Thesis Sharif University of Technology Mollaei, Yaser (Author) ; Nili, Masoud (Supervisor)

Abstract

Findings of economics in last decade shows that social and economic institutions have direct influence on economic performance of a society. However, these institutions are determined by the state. In different regimes, the political power is in the hand of different social groups with different preferences and goals; as a result, different social and economic policies and institutions are take place in different political regimes. In this research, we study economic performance of a society under control of two different political regimes: in first, the majority rules the state and in second, there is a totalitarian regime in which; the political power is concentrated in hand of a group of...