Combination Services in A Cloud Manufacturing System With Regard to Quality as A Fuzzy Criteria

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

Abstract

Today, due to the development of information technology and fierce competition among manufacturers, the need to reduce the production costs and increase the variety are strongly felt. Each process in the cloud manufacturing is first considered as a service product development, and then, specializing each of these services, provides us a lower cost, along with a higher accuracy, and quality.The modern world is the world full of uncertainty. The uncertainty, which causes the manufacturers to develop products that consume a large quantity of, fixed costs. That is why utilizing such a perspective can reduce investment risk in a new product development. Combining the production services by...

Location-aware Key Management in Wireless Sensor Networks

, M.Sc. Thesis Sharif University of Technology Nikounia, Hossein (Author) ; Jahangir, AmirHossein (Supervisor)

Abstract

Wireless sensor networks have many applications, vary in size, and are deployed in a wide variety of areas. They are often deployed in potentially adverse or even hostile environment so security issues are of much concern in these networks. Key management is a fundamental security issue in sensor networks. In this thesis, we are mainly focusing on key establishment and group rekeying schemes aspects of key management. Due to limited resources of sensor networks, key pre-distribution schemes are currently viewed as the most promising solution. Key predistribution in sensor networks refers to the problem of distributing secret keys among sensor nodes prior to deployment. Recently, many key...

A new Temporal Locality Method for Multi-Core Processor data Cache

, M.Sc. Thesis Sharif University of Technology Banihashemi, Borzoo (Author) ; Jahangir, AmirHossein (Supervisor)

Abstract

By increasing speed gap between microprocessors and off-chip Last Level Cache, Optimization in Last Level Cache makes improvement in system performance. With development of new generation of multi-core processors and sharing LLC between these cores, the so called issue of Memory Wall has caused an incremental effect of LLC on system performance. There are three approaches to use this memory more efficiently:
1. Increasing cache capacity
2. Making cache hierarchical and adding different layers to hierarchy
3. Improvement of replacement algorithms in cache memory
The first approach has not been used in regard with limitation of technology and growth of access time due to...

UWB Channel Modeling Using Time-Domain Ray Tracing

, M.Sc. Thesis Sharif University of Technology Nateghi, Amirhossein (Author) ; Shishegar, Amir Ahmad (Supervisor)

Abstract

Nowadays, wireless communication plays a key role in everyday lives and has many different applications. Today’s communication systems require high bandwidths in order to transfer data with higher bitrates. Among these, modeling a wireless channel is one of the most important challenges in wireless communications. Modeling an indoor Ultra-Wide-Band (UWB) wireless channel has been involved in a great number of researches. In order to model a UWB channel, we need to correctly investigate electromagnetic waves inside the buildings. Amongst different methods that are used for this aim, ray tracing method is one of the most accurate and fast ones. In this thesis, time-domain reflection and...

Strain rate sensitivity, work hardening, and fracture behavior of an Al-Mg TiO2 nanocomposite prepared by friction stir processing [electronic resource]

, Article Journal of Metallurgical and Materials Transactions A ; August 2014, Volume 45, Issue 9, P.4073-4088 Khodabakhshi, F ; Simchi, A. (Abdolreza) ; Kokabi, Amirhossein ; Nosko, Martin ; Svec, Peter ; Sharif University of Technology

Abstract

Annealed and wrought AA5052 aluminum alloy was subjected to friction stir processing (FSP) without and with 3 vol pct TiO2 nanoparticles. Microstructural studies by electron backscattered diffraction and transmission electron microscopy showed the formation of an ultra-fine-grained structure with fine distribution of TiO2 nanoparticles in the metal matrix. Nanometric Al3Ti and MgO particles were also observed, revealing in-situ solid-state reactions between Al and Mg with TiO2. Tensile testing at different strain rates determined that FSP decreased the strain rate sensitivity and work hardening of annealed Al-Mg alloy without and with TiO2 nanoparticles, while opposite results were obtained...

Response-only modal identification of structures using limited sensors

, Article Structural Control and Health Monitoring ; Volume 20, Issue 6 , 2013 , Pages 987-1006 ; 15452255 (ISSN) Abazarsa, F ; Ghahari, S. F ; Nateghi, F ; Taciroglu, E ; Sharif University of Technology

2013

Abstract

Herein, we propose a method based on the existing second-order blind identification of underdetermined mixtures technique for identifying the modal characteristics - namely, natural frequencies, damping ratio, and real-valued partial mode shapes of all contributing modes - of structures with a limited number of sensors from recorded free/ambient vibration data. In the second-order blind identification approach, second-order statistics of recorded signals are used to recover modal coordinates and mode shapes. Conventional versions of this approach require the number of sensors to be equal to or greater than the number of active modes. In the present study, we first employ a parallel factor...

Estimation of Bank Loan Interest Rate and Determining its Correlated Factors: A Case Study of Listed Companies in Iran

, M.Sc. Thesis Sharif University of Technology Nateghi, Morteza (Author) ; Madanizadeh, Ali (Supervisor) ; Mahmoodzadeh, Amineh (Supervisor)

Abstract

Bank loans are one of the main sources of financing for enterprises and the most important source of financing for large enterprises in Iran. Uncertainty about future conditions and asymmetric information between the bank and the firm puts the provision of loans at risk. According to the principle of proportionality of risk and return, the interest rate of bank facilities should be proportional to the risk that the bank incurs in return for granting the loan. In general, the interest rate of bank loans can be affected by three types of risks: the credit risk of the applicant firm, the risk of the lender bank and the macroeconomic environment risk. In this study, we try to estimate the...

, M.Sc. Thesis Sharif University of Technology Khodabakhshi, Farzad (Author) ; Kazeminezhad, Mohsen (Supervisor) ; Kokabi, Amirhossein (Supervisor)

Abstract

Considering that automobile weigth reduction in industry is important, improvement the strength of low carbon steel sheets is important. These sheets can be supported the service condition in lower thicknesses. Bulk nano-structured materials have been mostly attracted in materials science due to their unique physical and mechanical properties. Severe plastic deformation (SPD) is one of the most efficient methods to produce ultra fine grained or nano-structured materials. Materials produced by SPD are of great importance because of (1) non-porous structure, (2) great mechanical properties such as high strength and toughness and (3) proper dimension for mechanical and physical testing. ...

Development of High Entropy Filler Alloy for Brazing of Precipitation Hardened Ni-Base Superalloy IN-738

, M.Sc. Thesis Sharif University of Technology Amirhossein Sajjadi (Author) ; Pouranvari, Majid (Supervisor) ; Tavakoli, Rouhollah (Supervisor)

Abstract

Brazing is a crucial process for repairing and manufacturing high-temperature components made of precipitation-hardened superalloys. Boron-containing filler metals are amongst the most common filler metals used for repairing and joining superalloys. Although boron is an effective MPD in such filler metals, the formation of brittle boride intermetallics in the joining area (Athermal solidification zone and diffusion affected zone), due to the low solubility of boron in the matrix of superalloys, is inevitable. Isothermal Solidification is known as an effective technique for removing boride compounds in the joining area of brazed components. but as the time of isothermal solidification...

Radiation and convection heat transfer optimization with MHD analysis of a hybrid nanofluid within a wavy porous enclosure

, Article Journal of Magnetism and Magnetic Materials ; Volume 566 , 2023 ; 03048853 (ISSN) Hosseinzadeh, K ; Erfani Moghaddam, M. A ; Nateghi, S ; Behshad Shafii, M ; Ganji, D. D ; Sharif University of Technology

Elsevier B.V 2023

Abstract

Thermal performance maximization is a necessity in various systems that are dealing with any scale of heat flux. This requirement has been intensified due to introduction of more complex and highly crammed products, making heat dissipation a daunting task. Addressing this challenge, a curved porous star-shaped enclosure with a rounded cavity and occupied by hybrid nanoparticles of Fe3O4-Al2O3 scattered uniformly in 1-Hexanol has been simulated by Galerkin finite element method. The temperature difference between inner cavity and outer wavy surface stirred the heat flux within the bounded domain. The determinants of thermal evolution are classified by porosity alteration, radiation intensity,...

Bacterial biopolymers in tissue engineering and regenerative medicine; current applications and future perspective

, Article Biocatalysis and Agricultural Biotechnology ; Volume 54 , 2023 ; 18788181 (ISSN) Bakhshandeh, B ; Mohammadipanah, F ; Sadat Mirtaleb, M ; Maddah Gazani, M ; Nateghi, S ; Abbasi, P ; Sharif University of Technology

Elsevier Ltd 2023

Abstract

Tissue engineering (TE), a fast-growing field of regenerative medicine, has been designed to replace diseased or damaged tissues. As cellular factories, microbes produce a wide range of intracellular and extracellular biopolymers using energy resources. Bacterial biopolymers play an essential role in the competition of microorganisms with competitors. With the detailed knowledge of these bacterial metabolites, extensive applications have been provided in the medicine, food, and drug industry. Bacterial biopolymers, including polysaccharides, polyamides, polyphosphates, polyesters, and enzymes, with vast diversity and desirable properties, are the most frequently used products in TE. Herein...

PAIP 2020: microsatellite instability prediction in colorectal cancer

, Article Medical Image Analysis ; Volume 89 , 2023 ; 13618415 (ISSN) Kim, K ; Lee, K ; Cho, S ; Kang, D. U ; Park, S ; Kang, Y ; Kim, H ; Choe, G ; Moon, K. C ; Lee, K. S ; Park, J. H ; Hong, C ; Nateghi, R ; Pourakpour, F ; Wang, X ; Yang, S ; Fatemi Jahromi , A. R ; Khani, A. A ; Kim, H. R ; Choi, D. H ; Han, C. H ; Kwak, J. T ; Zhang, F ; Han, B ; Ho, D. J ; Kang, G. H ; Chun, S. Y ; Jeong, W. K ; Park, P ; Choi, J ; Sharif University of Technology

Elsevier B.V 2023

Abstract

Microsatellite instability (MSI) refers to alterations in the length of simple repetitive genomic sequences. MSI status serves as a prognostic and predictive factor in colorectal cancer. The MSI-high status is a good prognostic factor in stage II/III cancer, and predicts a lack of benefit to adjuvant fluorouracil chemotherapy in stage II cancer but a good response to immunotherapy in stage IV cancer. Therefore, determining MSI status in patients with colorectal cancer is important for identifying the appropriate treatment protocol. In the Pathology Artificial Intelligence Platform (PAIP) 2020 challenge, artificial intelligence researchers were invited to predict MSI status based on...