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A novel viewpoint to the green city concept based on vegetation area changes and contributions to healthy days: a case study of Mashhad, Iran
, Article Environmental Science and Pollution Research ; 2021 ; 09441344 (ISSN) ; Makian, M ; Gheibi, M ; Fathollahi Fard, A. M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
One of the significant challenges in urbanization is the air pollution. This highlights the need of the green city concept with reconsideration of houses, factories, and traffic in a green viewpoint. The literature review confirms that this reconsideration for green space has a positive effect on the air quality of large cities and to reduce the air pollution. The purpose of this study is to evaluate the annual vegetation changes in the green space of Mashhad, Iran as a very populated city in the middle east to study the air pollution. To investigate the relationship between the air pollution and vegetation, the Landsat 8 satellite images for summer seasons of 2013–2019 were used to extract...
A novel viewpoint to the green city concept based on vegetation area changes and contributions to healthy days: a case study of Mashhad, Iran
, Article Environmental Science and Pollution Research ; Volume 29, Issue 1 , 2022 , Pages 702-710 ; 09441344 (ISSN) ; Makian, M ; Gheibi, M ; Fathollahi Fard, A. M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
One of the significant challenges in urbanization is the air pollution. This highlights the need of the green city concept with reconsideration of houses, factories, and traffic in a green viewpoint. The literature review confirms that this reconsideration for green space has a positive effect on the air quality of large cities and to reduce the air pollution. The purpose of this study is to evaluate the annual vegetation changes in the green space of Mashhad, Iran as a very populated city in the middle east to study the air pollution. To investigate the relationship between the air pollution and vegetation, the Landsat 8 satellite images for summer seasons of 2013–2019 were used to extract...
A new approach for multi-source data prediction in wireless sensor networks: Collaborative filtering
, Article 2012 International Conference on Wireless Communications and Signal Processing, WCSP 2012 ; 2012 ; 9781467358293 (ISBN) ; Ashouri, M ; Gheibi, S ; Hemmatyar, A. M. A ; Sharif University of Technology
2012
Abstract
The prime shortcoming of Wireless Sensor Networks (WSNs) is their energy constraint. The main energy consumer in a sensor node is its radio transmitter. One of the most effective methods to reduce the data transmission rate is data prediction. By data prediction, the amount of transmitted data is reduced; which results in energy saving and the longevity of the network life. Environmental variations almost have similar effects on different sensor sources in a sensor device. So, considering the correlation between different sources reduces the noise impact and increases data prediction accuracy. In this paper, temporal and multi-source correlations are used, to reduce data transmission in...
A Semi-Emperical Model for Small Starin Shear Modulus of Unsaturated Low Plasticity Soils
, M.Sc. Thesis Sharif University of Technology ; Khosravi, Ali (Supervisor)
Abstract
The shear modulus of soils is a key material quantity which is frequently used in the evaluation of wave propagation through soil layers in dynamic response analyses for many geotechnical systems. The shear modulus, G, is defined as the slope of the shear stress-strain hysteresis loop and is significantly influenced by the shear strain amplitude induced in a soil specimen. Of particular interest in geotechnical engineering, the value of shear modulus for strains less than 10-6 defined as the small strain shear modulus, Gmax. The early experimental studies on the shear modulus of water-saturated or dry soil showed that shear modulus is highly dependent on mean effective sress, p´, and void...
Mechanistic evaluation of cationic dyes adsorption onto low-cost calcinated aerated autoclaved concrete wastes
, Article International Journal of Environmental Science and Technology ; 2021 ; 17351472 (ISSN) ; Eftekhari, M ; Tabrizi, M. G ; Fathollahi Fard, A. M ; Tian, G ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
Application of construction and demolition (C&D) wastes were considered as sustainable development goals (SDGs) for maintaining raw materials. Also, lightweight concretes such as aerated autoclaved concrete (AAC) were used for partitioning spaces in the building industry. Moreover, the waste products of the mentioned materials were increased due to the rise of old construction demolitions. This study contributes a calcinated aerated autoclaved concrete (CAAC) which is efficient, powerful, highly rapid, non-expensive and novel adsorbent for the removal of cationic dyes including malachite green (MG), methyl violet (MV) and methylene blue (MB) form water samples. The impacts of different...
Mechanistic evaluation of cationic dyes adsorption onto low-cost calcinated aerated autoclaved concrete wastes
, Article International Journal of Environmental Science and Technology ; Volume 19, Issue 7 , 2022 , Pages 6429-6444 ; 17351472 (ISSN) ; Eftekhari, M ; Tabrizi, M. G ; Fathollahi Fard, A. M ; Tian, G ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Application of construction and demolition (C&D) wastes were considered as sustainable development goals (SDGs) for maintaining raw materials. Also, lightweight concretes such as aerated autoclaved concrete (AAC) were used for partitioning spaces in the building industry. Moreover, the waste products of the mentioned materials were increased due to the rise of old construction demolitions. This study contributes a calcinated aerated autoclaved concrete (CAAC) which is efficient, powerful, highly rapid, non-expensive and novel adsorbent for the removal of cationic dyes including malachite green (MG), methyl violet (MV) and methylene blue (MB) form water samples. The impacts of different...
Characterizing the variation of small strain shear modulus for silt and sand during hydraulic hysteresis
, Article 3rd European Conference on Unsaturated Soils, 12 September 2016 through 14 September 2016 ; Volume 9 , 2016 ; 22671242 (ISSN) ; Rahimi, M ; Shahbazan, P ; Pak, A ; Gheibi, A ; Sharif University of Technology
EDP Sciences
2016
Abstract
Experimental studies have indicated that the small strain shear modulus, Gmax, of unsaturated silt and clay has a greater amount during imbibition than during drainage, when presented as a function of matric suction. However, due to material properties and inter-particle forces, different behavior is expected in the case of sand. Although considerable research has been devoted in recent years to characterize the behaviour of Gmax of sand during drainage, rather less attention has been paid to the effect of hydraulic hysteresis on Gmax and its variations during imbibition. In the study presented herein, an effort has been made to compare the Gmax behavior of specimens of silt and sand during...
Using Game Theory to Model Covering and Packing Problems
, M.Sc. Thesis Sharif University of Technology ; Zarrabi-Zadeh, Hamid (Supervisor)
Abstract
Game theory is widely used to model diverse phenomena in the real world such as people’s behavior in elections and auctions. It also has natural applications to some other areas such as computer networks, cryptography, and security. In this thesis, we present a general approach to model two important classes of optimization problems, namely, covering and packing problems, using game theory concepts. This model provides an integrated language to explain the problems, and enables us to use game-theoretic tools to further explore and analyze the problems. In our proposed model, the optimum solutions of the modeled problem are always one of the equilibria of the game. Therefore, one can find...
GPU-based Acceleration of Isogeny-based Cryptography
, M.Sc. Thesis Sharif University of Technology ; Bayat Sarmadi, Siavash (Supervisor)
Abstract
Post-quantum cryptography, as one of the newest groups of cryptographic algorithms, is thought to be secure against most sophisticated attacks by the groundbreaking quantum computers. Isogeny-based cryptography is an appealing contender among them due to its exceptional characteristics, especially the shortest public key in key encapsulation, encryption and decryption amid the other nominees of NIST post-quantum standard. However, its high computational complexity is a significant drawback. This research aims to increase the performance of isogeny-based cryptography in the most compute-intensive part, both in throughput and latency perspectives on GPUs and CPUs, which are the most widespread...
Design and Analysis of a Simple Low-Power Network-on-Chip
, M.Sc. Thesis Sharif University of Technology ; Sarbazi Azad, Hamid (Supervisor) ; Hesabi, Shahin (Supervisor)
Abstract
The advancement of technology in the semiconductor industry and the resulting increase in the number of transistors on a chip has led to an increase in the number of processing cores an increase in the number of processing cores in a system on chip (SoC). A surge in the number of processing cores, makes their communication more and more noteworthy. This communication is established through the network on chip (NoC). One of the main challenges in NoC design is power management, as it constitutes a high percentage of the overall power consumption of the chip. One of the most power-hungry components of NoC is the router. According to our observation, some of the components of the routers are...
Probability of missed detection as a criterion for receiver placement in MIMO PCL
, Article IEEE National Radar Conference - Proceedings, 7 May 2012 through 11 May 2012, Atlanta, GA ; 2012 , Pages 0924-0927 ; 10975659 (ISSN) ; 9781467306584 (ISBN) ; Chitgarha, M. M ; Radmard, M ; Nayebi, M. M ; Sharif University of Technology
IEEE
2012
Abstract
Using multiple antennas at the transmit and receive sides of a passive radar brings both the benefits of MIMO radar and passive radar. However one of the obstacles arisen in such configuration is the receive antennas placement in proper positions so that the radar performance is improved. Here we just consider the case of positioning one receiver among multiple illuminators of opportunity. Indeed it is a start for the solution of optimizing the geometry of the multiple receivers in a passive radar
An efficient method for the ring opening of epoxides with aromatic amines by Sb(III) chloride under microwave irradiation
, Article Journal of Chemical Research ; Issue 4 , 2008 , Pages 220-221 ; 03082342 (ISSN) ; Hashemi, M. M ; Mottaghi, M. M ; Foroughi, M. M ; Sharif University of Technology
2008
Abstract
SbCl3 supported on montmorillonite K-10 is an efficient catalyst for the ring opening of epoxides with aromatic amines under solvent-free conditions and microwave irradiation to give the corresponding b-amino alcohols in high yields with high regioselectivity
Resource allocation for uav-enabled integrated sensing and communication (isac) via multi-objective optimization
, Article ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings ; Volume 2023-June , 2023 ; 15206149 (ISSN); 978-172816327-7 (ISBN) ; Naghsh, M. M ; Karbasi, M ; Nayebi, M. M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2023
Abstract
In this paper, we consider an integrated sensing and communication (ISAC) system with wireless power transfer (WPT) where an unmanned aerial vehicle (UAV)-based radar serves a group of energy-limited communication users in addition to its sensing functionality. In this architecture, the radar senses the environment in phase 1 (namely sensing phase) and mean-while, the communications users (nodes) harvest and store the energy from the radar transmit signal. The stored energy is then used for information transmission from the nodes to UAV in phase 2, i.e., uplink phase. Performance of the radar system depends on the transmit signal as well as the receive filter; the energy of the transmit...
MIMO radar signal design to improve the MIMO ambiguity function via maximizing its peak
, Article Signal Processing ; Volume 118 , 2016 , Pages 139-152 ; 01651684 (ISSN) ; Radmard, M ; Nazari Majd, M ; Karbasi, S. M ; Nayebi, M. M ; Sharif University of Technology
Elsevier
2016
Abstract
One of the important obstacles in MIMO (Multiple Input Multiple Output) radars is the issue of designing proper transmit signals. Indeed, the capability of signal design is a significant advantage in MIMO radars, through which, the system can achieve much better performance. Many different aspects of this performance improvement have been considered yet, and the transmit signals have been designed to attain such goal, e.g., getting higher SNR or better detector's performance at the receiver. However, an important tool for evaluating the radar's performance is its ambiguity function. In this paper, we consider the problem of transmit signal design, in order to optimize the ambiguity function...
Detection-localization tradeoff in MIMO radars
, Article Radioengineering ; Volume 26, Issue 2 , 2017 , Pages 581-587 ; 12102512 (ISSN) ; Radmard, M ; Chitgarha, M. M ; Bastani, M. H ; Nayebi, M. M ; Sharif University of Technology
2017
Abstract
Two gains play key roles in recently developed MIMO wireless communication systems: "spatial diversity" gain and "spatial multiplexing" gain. The diversity gain refers to the capability to decrease the error rate of the MIMO channel, while the multiplexing gain implicitly refers to the amount of increase in the capacity of the MIMO channel. It has been shown that there is a fundamental tradeoff between these two types of gains, meaning interplay between increasing reliability (via an increase in the diversity gain) and increasing data rate (via an increase in the multiplexing gain). On the other hand, recently, MIMO radars have attracted much attention for their superior ability to enhance...
Antenna placement and power allocation optimization in MIMO detection
, Article IEEE Transactions on Aerospace and Electronic Systems ; Vol. 50, Issue 2 , April , 2014 , pp. 1468-1478 ; Chitgarha, M. M ; Majd, M. N ; Nayebi, M. M ; Sharif University of Technology
2014
Abstract
It is a well known fact that using multiple antennas at transmit and receive sides improves the detection performance. However, in such multiple-input multiple-output (MIMO) configuration, proper positioning of transmitters and receivers is a big challenge that can have significant influence on the performance of the overall system. In addition, determining the power of each transmitter under a total power constraint is a problem that should be solved in order to enhance the performance and coverage of such a system. In this paper, we design the Neyman-Pearson detector under the Rayleigh scatter model and use it to introduce a criterion for the antenna placement at both transmit and receive...
Ambiguity function of MIMO radar with widely separated antennas
, Article Proceedings International Radar Symposium ; 16 -18 June , 2014 ; ISSN: 21555753 ; Chitgarha, M. M ; Nazari Majd, M ; Nayebi, M. M ; Sharif University of Technology
2014
Abstract
There has been much interest, recently, towards exploiting the Multiple-Input Multiple-Output (MIMO) technique in radar. It is shown that using multiple antennas at transmit and receive sides can improve the performance of the system. However, in order to analyze the system's performance, its ambiguity function, i.e. the ambiguity function of a MIMO radar, is needed to be defined. In this paper, beginning from the information theoretic definitions, we derive such function, specifically for a MIMO radar with widely separated antennas
Choosing the position of the receiver in a MISO passive radar system
, Article European Microwave Week 2012: "Space for Microwaves", EuMW 2012, Conference Proceedings - 9th European Radar Conference, EuRAD 2012 ; 2012 , Pages 318-321 ; 9782874870293 (ISBN) ; Majd, M. N ; Radmard, M ; Nayebi, M. M ; Sharif University of Technology
2012
Abstract
By combining the two ideas of MIMO (Multiple Input Multiple Output) and PCL (Passive Coherent Location) in radar, one can achieve the advantages of both recently developed techniques simultaneously. While using multiple antennas at the receive side provides a spatial diversity of the object to be detected, using multiple illuminators of opportunity, most importantly, makes the radar covert to the interceptors. One obstacle in such MIMO configuration is choosing the positions of the receive antennas. In this paper, after analyzing the Neyman-Pearson detector for the DVB-T based PCL, we introduce the probability of missed detection as a criterion to place the receive antenna. Here, we only...
Adaptive filtering techniques in passive radar
, Article Proceedings International Radar Symposium, Dresden ; Volume 2 , June , 2013 , Pages 1067-1078 ; 21555753 (ISSN) ; 9783954042234 (ISBN) ; Radmard, M ; Majd, M. N ; Nayebi, M. M ; Sharif University of Technology
2013
Abstract
One of the most important obstacles in passive radar applications is removing the direct signal from the target channel. Otherwise, week echoes from the targets in the target channel would be ignored due to the limited dynamic range of the system. One of the most effective techniques in this field is using adaptive filters. In this paper various adaptive filters are introduced and their performances are shown and compared
Ambiguity function based receiver placement in multi-site radar
, Article 2016 CIE International Conference on Radar, RADAR 2016, 10 October 2016 through 13 October 2016 ; 2017 ; 9781509048281 (ISBN) ; Chitgarha, M. M ; Nazari Majd, M ; Nayebi, M. M ; Sharif University of Technology
2017
Abstract
It has been shown that using multiple antennas in a radar system improves the performance considerably, since multiple target echoes are received from different aspect angles of the target. In this way, the target detection is improved. However, when using multiple antennas, some problems, such as designing the transmit signals, synchronization, etc. emerge that should be solved. One of such problems is the receiver placement. Receiver placement deals with choosing a proper position for the receive antenna in order to optimize the whole system's performance. In this paper, a receiver placement procedure based on improving the radar ambiguity function is proposed for the case of a multisite...