Immobilization of α -chymotrypsin on the surface of magnetic/gold core/shell nanoparticles

, Article Journal of Nanotechnology ; Volume 2013 , 2013 ; 16879503 (ISSN) Kamal Ahmadi, M ; Vossoughi, M ; Sharif University of Technology

Hindawi Publishing Corporation 2013

Abstract

Over the last decade, nanoparticles used as protein carriers have opened new avenues for a variety of biomedical applications. The main concern for these applications is changes in biological activity of immobilized proteins due to conformational changes on the surface of the carrier. To evaluate this concern, the preparation and biocatalyst activity of α-chymotrypsin-Fe 3O4 @ Au core/shell nanoparticles were investigated. First, Fe3O4 @ Au core/shell nanoparticles were synthesized by coprecipitation method and citrate reduction of HAuCl 4. TEM imaging revealed a core size of 13 ± 3 nm and a shell thickness of 4 ± 1 nm for synthesized nanoparticles. X-ray diffraction (XRD) was used to study...

Elastic Responses of a Half-Space Reinforced by a Buried Extensible Membrane under Internal Loading

, M.Sc. Thesis Sharif University of Technology Ahmadi Kamal Abad, Kasra (Author) ; Eskandari, Morteza (Supervisor)

Abstract

In order to improve mechanical properties and increase the load capacity of soil so many different methods are innovated and utilized. Through This variety we can mention cement and asphalt concrete pavements which are the most common methods, cement sprinkling for consolidation of inclined surfaces and utilizing geotextiles and geomembranes which are recent methods. As far as a method becomes more common in industry, analytical study on effect of these methods on soil properties drew more attention in researches.In this research a homogenous elastic half-space is reinforced by an extensible thin plate and studied under various loads. The plate is considered as a buried infinite plane with...

Study of Enzyme (Chymotrypsin) -Core/Shell (Fe3O4 @ Au) Nanoparticle Bioconjugate

, M.Sc. Thesis Sharif University of Technology Kamal Ahmadi, Mahmoud (Author) ; Vosoughi, Manoochehr (Supervisor) ; Seyf Kordi, Ali Akbar (Supervisor)

Abstract

Conjugation of proteins to nanoparticles has numerous applications in sensing, imaging, delivery, catalysis, therapy and control of protein structure and activity. Therefore, characterizing the nanoparticle–protein interface is of great importance. A variety of covalent and non-covalent linking chemistries have been reported for nanoparticle attachment. Typically, a specific protein residue is linked directly to the nanoparticle core or to the ligand. As conjugation often affects the protein structure and function, techniques to probe structure and activity are assessed Characterization studies of nanoparticle–protein complexes show that the structure and function are influenced by the...

Traffic Videos Content Analysis Based on Topic Models

, Ph.D. Dissertation Sharif University of Technology Ahmadi, Parvin (Author) ; Tabandeh, Mahmoud (Supervisor) ; Gholampour, Iman (Co-Advisor)

Abstract

Motion pattern analysis in traffic videos can be directly employed for scene analysis, rule mining, abnormal event detection, traffic phase detection, etc. The most successful and newest methods for complex traffic scene analysis are based on topic models. Topic models have been developed for text processing and as they have not been yet optimized for traffic video processing, they are still far away from optimal efficiency. In this thesis, firstly we propose two unsupervised methods for traffic video analysis based on non-probabilistic topic models. In the first proposed method, we use Group Sparse Topical Coding (GSTC) and an improved version of it for learning typical motion patterns...

Joint Modelling of Telecommuting’s Feasibility and Freguency for Employees, Application of Copula Models

, M.Sc. Thesis Sharif University of Technology Kamal, Kimia (Author) ; Kermanshah, Mohammad (Supervisor)

Abstract

Since expansion of communication technology, telecommuting has gained attention from transportation planners as an approach in field of demand management. In this research, joint effects of feasibility of telecommuting for the employees of each organization and the relevant frequency of employees have been evaluated by using the copula model as the most recent conventional way of developing a joint model since the last few years. The result of telecommuting acceptance is that after presenting the project to each organization, the head employer measures the appropriateness of the project for employees and if he reaches a consensus on the success of the project, the employees get involved and...

Developing a Method for Fatigue Life Assessment of Vehicle Biw by Considering Spot Welding Connections

, M.Sc. Thesis Sharif University of Technology Ahmadi, Alireza (Author) ; Farrahi, Gholamhossein (Supervisor) ; Chizari, Mahmoud (Supervisor) ; Reza Kashyzadeh, Kazem (Co-Supervisor)

Abstract

One of the most important considerations in the vehicle design procedure is the durability of the components. Among different parts of a vehicle, the body is the main load-bearing component and as a result, its durability is critical. Due to the expensive and time-consuming nature of fatigue tests, finite element based durability analysis is of great interest among automotive industry. The aim of this research is to provide an algorithm for a more accurate and efficient durability analysis of the vehicle body by considering inertia effects. By using the multi-body dynamics model of the full vehicle and the finite element model of the vehicle body, the vehicle body structure is analyzed from...

GPH: A group-based partitioning scheme for reducing total power consumption of parallel buses

, Article Microprocessors and Microsystems ; Volume 35, Issue 1 , 2011 , Pages 68-80 ; 01419331 (ISSN) Kamal, M ; Koohi, S ; Hessabi, S ; Sharif University of Technology

2011

Abstract

Two main sources for power dissipation in parallel buses are data transitions on each wire and coupling between adjacent wires. So far, many techniques have been proposed for reducing the self and coupling powers. Most of these methods utilize one (or more) control bit(s) to manage the behavior of data transitions on the parallel bus. In this paper, we propose a new coding scheme, referred to as GPH, to reduce power dissipation of these control bits. GPH coding scheme employs partitioned Bus Invert and Odd Even Bus-Invert coding techniques. This method benefits from Particle Swarm Optimization (PSO) algorithm to efficiently partition the bus. In order to reduce self and coupling powers of...

A novel partitioned encoding scheme for reducing total power consumption of parallel bus

, Article 13th International Computer Society of Iran Computer Conference on Advances in Computer Science and Engineering, CSICC 2008, Kish Island, 9 March 2008 through 11 March 2008 ; Volume 6 CCIS , 2008 , Pages 90-97 ; 18650929 (ISSN); 3540899847 (ISBN); 9783540899846 (ISBN) Kamal, M ; Koohi, S ; Hessabi, S ; Sharif University of Technology

2008

Abstract

Two main sources for power dissipation in parallel buses are data transitions on each wire and coupling between adjacent wires. There are many techniques for reducing the transition and coupling powers. These methods utilize extra control bits to manage the behavior of data transitions on parallel bus. In this paper, we propose a new coding scheme which tries to reduce power dissipation of control bits. The proposed method employs partitioned Bus Invert and Odd Even Bus Invert coding techniques. This method benefits from Particle Swarm Optimization (PSO) algorithm to efficiently partition the bus. In order to reduce transition and coupling power of control bits, it finds partitions with...

An Interior Needle Electropolymerized Pyrrole-Based Coating for Headspace Solid-Phase Dynamic Extraction of Chlorophenols

, M.Sc. Thesis Sharif University of Technology Kamal Abyaneh, Zahra (Author) ; Bagheri, Habib (Supervisor)

Abstract

Nowadays, the inside needle capillary adsorption trap (INCAT) technique as a solventless sample preparation approach and alternative extraction method derived from SPME is gaining rising attentions. The INCAT and needle-trap devices are inexpensive, robust, reusable, and are applicable for sampling and analyzing suitable organic compounds from many different sample matrices. Compared to the fragile silica-based SPME fiber, the needle device is nearly impossible to break mechanically. In addition, the extraction medium possesses quite a large extraction phase volume and a powerful preconcentration capability. Similar to SPME, needle-like devices are particularly convenient for automation and...

Control of Nonlinear Systems With Predefined Output Transient Performance

, M.Sc. Thesis Sharif University of Technology Kamal Amiri, Ali (Author) ; Shahrokhi, Mohammad (Supervisor)

Abstract

This project is aimed to design a controller for nonlinear systems that satisfy a prescribed performance while guaranteeing close-loop stability. To do this, the controller must be designed in such a way that the transient response of the system has had these performance indices and does not exceed them. These performance indices predefine some constraints for systems’ output.A comprehensive form for the model system, the unknown dynamics of the system, consideration of a variety of constraints on the system input, usage of the time-finite method for the residence time and consideration of just one tuning parameter to reduce the computation load, are among the other benefits for the proposed...

Role of Base Metal Composition in Isothermal Solidification Time During Diffusion Brazing of Nickelbased Superalloys

, M.Sc. Thesis Sharif University of Technology Mohammad Kamal, Helia (Author) ; Pouranvari, Majid (Supervisor)

Abstract

The nickel-based superalloys play a key role in the development of aircraft and power-generation turbines due to their exceptional properties of high temperature strength, toughness, crack growth resistance and resistance to degradation corrosive and oxidisation environment.In this thesis, the role of base metal composition in isothermal solidification time during diffusion brazing of Nickel-based super alloys was investigated. To achieve this aim, four different super alloys Hynes230, Hastalloy X, Nimonic 263 and Monel were used in similar joining systems. Systems of H230/H230, HX/HX, C263/C263, and Monel/Monel were joined by BNi2 interlayer at 1323K and for different times, until the...

GABIST: A new methodology to find near optimal LFSR for BIST structure

, Article 14th IEEE International Conference on Electronics, Circuits and Systems, ICECS 2007, Marrakech, 11 December 2007 through 14 December 2007 ; 2007 , Pages 1107-1110 ; 1424413788 (ISBN); 9781424413782 (ISBN) Kamal, M ; Salmani Jelodar, M ; Hessabi, S ; Sharif University of Technology

2007

Abstract

Fault coverage and test time have important roles in using Built in self-test (BIST). Two parameters are crucial and effective in BIST design: LFSR's polynomial (or configuration) and its initial seed. In this paper we propos a practical method for finding near optimal LFSR with genetic algorithm (GA) and show that LFSR is a good TPG compared with other TPGs. In this method, the candidate seeds are achieved through a deterministic approach, and an evolutionary approach is employed to obtain the LFSR configurations for the desired fault coverage under test time constraint. The configurations are encoded in binary chromosomes. The evolution process evolves the fittest configurations to achieve...

A Framework for Evaluating the Effect of Queue on Customer Perception

, M.Sc. Thesis Sharif University of Technology Rezvaninejad, Kamal Addin (Author) ; Najmi, Manouchehr (Supervisor)

Abstract

Queue is crucial in new atmosphere of business. Firms and people see the dark side of this phenomenon. Investigation on The other side of queue is our main purpose of this study. Examining the relationship between queue and Perceived Quality, Price, Sacrifice, Value, and willingness to buy that make our conceptual framework and hypotheses is our primary objective.Questionnaire designed for evaluating construct. For each construct, standard scale was used. A survey was conducted in Iranian universities. The final sample includes 295 respondents. Regression analyses were performed.Results show significant relationship between our construct that confirm the other side of queue. Results show...

A stability-based model of a growing spine with adolescent idiopathic scoliosis: A combination of musculoskeletal and finite element approaches

, Article Medical Engineering and Physics ; Volume 64 , 2019 , Pages 46-55 ; 13504533 (ISSN) Kamal, Z ; Rouhi, G ; Arjmand, N ; Adeeb, S ; Sharif University of Technology

Elsevier Ltd 2019

Abstract

Using a combined musculoskeletal and finite element (FE) approach, this study aimed to evaluate stability-based muscle forces in a spine with adolescent idiopathic scoliosis (AIS) as compared to a normal spine; and subsequently, determine the effects of stress distribution on the growth plates (GPs) of the growing spine. For this purpose a nonlinear 3D FE model of one normal and one scoliotic thoracolumbar spine, consisting of GPs attached to rigid L1 to L4 vertebrae, were developed using computed tomography images coupled with a growth modulation using the Stokes’ model. Corresponding well with recent in-vivo and in-vitro studies, results of the models predicted intradiscal pressures at the...

The Behavior of Supporting Structures with Pretension Anchors by Geotechnical Softwares

, M.Sc. Thesis Sharif University of Technology Ahmadi, Alireza (Author) ; Ahmadi, Mohammad Mehdi (Supervisor)

Abstract

In recent years, due to urban expansion and population growth, number of floors and excavations depth has increased. Stabilization of excavations is one of the most important issues in geotechnical engineering. Today, one of the most widely used methods that is used in deep excavations is brace soil by steels and pretension them. In this thesis tries to evaluate static behavior of flexible supporting structures with pretension anchors by using PLAXIS2D, FLAC3D and GEOSTUDIO softwares. The objective of this modeling is better understanding the static behavior of walls, comparing the two and three dimensional modeling and the effect of corners of excavation on deformation. The results shows...

An efficient uniform-segmented neuron model for large-scale neuromorphic circuit design: Simulation and FPGA synthesis results

, Article IEEE Transactions on Circuits and Systems I: Regular Papers ; Volume 66, Issue 6 , 2019 , Pages 2336-2349 ; 15498328 (ISSN) Jokar, E ; Abolfathi, H ; Ahmadi, A ; Ahmadi, M ; Sharif University of Technology

Institute of Electrical and Electronics Engineers Inc 2019

Abstract

Large-scale simulation of spiking neural networks on hardware with a remarkable resemblance to their mathematical models is a key objective of the neuromorphic discipline. This issue is, however, considerably resource-intensive due to the presence of nonlinear terms in neuron models. This paper proposes a novel uniform piecewise linear segmentation approach for nonlinear function evaluations. Employing the proposed approach, we present a uniform-segmented adaptive exponential neuron model capable of accurately producing various responses exhibited by the original model and suitable for efficient large-scale implementation. In contrast to previous nonuniform-segmented neuron models, the...

Optimum receiver design for transmitted-reference signaling [electronic resource]

, Article IEEE Transactions on Communications ; May 2010, Volume 58, Issue 5, P.1589-1598 Farhang, M. (Mahmoud) ; Salehi, J. A ; Sharif University of Technology

Abstract

Autocorrelation receiver (AcR) is usually used as the general receiver for transmitted reference (TR) communication systems on a quite intuitive basis. In this paper, we apply the principle of statistical invariance to obtain the optimum TR receiver on a decision-theoretic basis, and it is shown that the autocorrelation receiver is optimal only in a special case. Performance of the optimum receiver and the suboptimum AcR for some important modulation schemes is also evaluated. The results imply that allocating a part of the transmitted energy and bandwidth to reference pulses would not help improve the performance of the system and the optimal performance might be achieved via much simpler...

A simple and efficient method for segmentation and classification of aerial images

, Article Proceedings of the 2013 6th International Congress on Image and Signal Processing, CISP 2013 ; Volume 1 , 2013 , Pages 566-570 ; 9781479927647 (ISBN) Ahmadi, P ; Sharif University of Technology

2013

Abstract

Segmentation of aerial images has been a challenging task in recent years. This paper introduces a simple and efficient method for segmentation and classification of aerial images based on a pixel-level classification. To this end, we use the Gabor texture features in HSV color space as our best experienced features for aerial images segmentation and classification. We test different classifiers including KNN, SVM and a classifier based on sparse representation. Comparison of our proposed method with a sample of segmentation pre-process based classification methods shows that our pixel-wise approach results in higher accuracy results with lower computation time

Prediction of pore facies using GMDH-type neural networks: a case study from the South Pars gas field, Persian Gulf basin

, Article Geopersia ; Volume 8, Issue 1 , March , 2018 , Pages 43-60 ; 22287817 (ISSN) Sfidari, E ; Kadkhodaie, A ; Ahmadi, B ; Ahmadi, B ; Faraji, M. A ; Sharif University of Technology

University of Tehran 2018

Abstract

Pore facies analysis plays an important role in the classification of reservoir rocks and reservoir simulation studies. The current study proposes a two-step approach for pore facies characterization in the carbonate reservoirs with an example from the Kangan and Dalan formations in the South Pars gas field. In the first step, pore facieswere determined based on Mercury Injection Capillary Pressure (MICP) data in corporation with the Hierarchical Clustering Analysis (HCA) method. Each pore facies represents a specific type of pore geometry indicating the interaction between the primary rock fabric and its diagenetic overprints. In the next step, polynomial meta-models were established based...

The Feasibility Study of Micronized Powder Plant for Exporting (UNIDO METOD)

, M.Sc. Thesis Sharif University of Technology (Author) ; Hooshmand, Mahmoud (Supervisor)

Abstract

This thesis deals with the development of a hypothetical micronized powder factory and trying to test and engage in this hypothetical development of the following plant, it considers following factors:
1-Domestic & International market
2-Plant location
3-Plant design & development
a.machinery
b.technology & equipment
c.human resource
d.environment
e.packing
4-raw material
5-shipping & transport
To evaluate above factors the UNIDO methodology is used in this research work. The UNIDO methods are using a process by which feasibility studies of production facilities or plant are base on. After reviewing a variety of factors, ranging from financial...