Sharif Digital Repository

Advanced metering infrastructure (AMI) provides 2-way communications between the utility and the smart meters. Developing authenticated key exchange (AKE) and broadcast authentication (BA) protocols is essential to provide secure communications in AMI. The security of all existing cryptographic protocols is based on the assumption that secret information is stored in the nonvolatile memories. In the AMI, the attackers can obtain some or all of the stored secret information from memories by a great variety of inexpensive and fast side-channel attacks. Thus, all existing AKE and BA protocols are no longer secure. In this paper, we investigate how to develop secure AKE and BA protocols in the... 

In this paper a self-oscillating mixer is presented fundamental signal generated by the oscillator subcircuit in the mixing process. The oscillator core consumes 3mA of current from a 1.8 V DC supply and results in an output power of -0.867 dBm per oscillator, and a measured phase noise of -91, -102 and -108 dBc/Hz at 100 KHz, 600 KHz and 1 MHz from the carrier, respectively. In the mixing process the proposed mixer achieved IIP3 of 0 dBm with conversation gain of 1.93 dB. The circuit was designed and simulated in 0.18-μm CMOS technology by ADS2010  

Copper slag (CS) is an industrial waste, which is generally disposed of in landfills, posing threats to the environment. Alternatively, it can be used as natural aggregate replacement in concrete/mortar, however, it results in a significant increase in material density, production and handling cost. The use of crumb rubber in combination with CS can overcome these problems, but there was no prior study on effect of such combination on the properties of alkali activated mortars (AAMs). The primary aim of this study is to address the problem stated above by replacing CS with 5, 10, 15% (by volume) crumb rubber in alkali-activated slag mortars. Furthermore, the effect of pre-treatment of crumb... 

The authors regret that there was an error in the SEM images presented in Fig. 4 of the article. The corrected SEM images as presented here. It is noteworthy that this change does not affect any of the conclusions. The authors would like to apologize for any inconvenience caused. © 2022 Elsevier Ltd  

In this study, the optimum curing temperature and alkaline solution-to-binder (S:B) ratio of geopolymer mortars based on waste ceramic powder (WCP) were investigated. For this purpose, mixes with S:B ratios of 0.4–0.7 were prepared and cured at 60, 75, 90, and 105 °C. The density, compressive and flexural strengths were measured at 3, 7, 14, and 28 days. Higher S:B ratios enhanced the flow of the fresh mortar. The optimum mortar was obtained for S:B ratio of 0.6 and curing temperature of 90 °C. The SEM analysis revealed that the optimal mix had a dense matrix with minimum pores. © 2019 Elsevier Ltd  

This paper studied the durability, microstructure, and fire behavior of lightweight mortars based on cement, metakaolin (MK), ultrafine ground granulated blast furnace slag (UGGBFS), ceramic waste powder (CWP), and clay brick waste powder (CBWP). Two sets of mixes were prepared with two types of lightweight aggregate including lightweight expanded clay aggregate (LECA) and pumice aggregate. Regarding the durability assessment, the electrical resistivity and water absorption of the mortars were measured. The UGGBFS-based alkali-activated mortar with pumice aggregate exhibited the highest electrical resistivity and lowest water absorption, while CBWP-based geopolymer mortar with LECA showed... 

The authors regret that there was an error in the caption of Fig. 15. The corrected caption for Fig. 15 as presented here. It is noteworthy that this change does not affect any of the conclusions. Fig. 15. SEM micrograph of geopolymer mortar with clay brick waste: (a) with LECA and magnification of 60×, (b) with pumice aggregates and magnification of 2000×, (c) with pumice aggregates and magnification of 500×, (d) with pumice aggregates and magnification of 1000×. The authors would like to apologize for any inconvenience caused. © 2022 Elsevier Ltd  

One of the most used types of auctions in the smart grid is the double auction, in which both buyers and sellers can respectively submit their bids and asks to participate in the auction. In recent years, many schemes have been designed to propose a double auction mechanism for the smart grids; however, few of these schemes consider the information security aspects and users’ privacy. In this paper, we propose a protocol that helps different double auction mechanisms be implemented securely in the smart grids. This protocol not only can satisfy the security requirements of a double auction scheme but is also compatible with the smart grid technologies. In this scheme, in order to preserve... 

The authors regret that there was an error in the labels of Fig. 5. The authors have re-analyzed the XRD patterns of micro-silica for more accuracy of the presented information. Please refer to the corrected figure as presented here. It is noteworthy that this change does not affect any of the conclusions. The authors would like to apologise for any inconvenience caused. © 2021 Elsevier Ltd  

A 6-bit passive phase shifter for S frequency band has been designed in a standard HEMT technology. A new switched-network topology has been proposed for implementing the 5.625 phase shift step which these digital bits are series with each other. We used Advanced Design System (ADS2010) to perform simulations. These digital bits will produce 64 different mode phase shift of -177.15 to +177.15 degree. In all cases simulation obtained less than 1 % error  

The authors regret that there were minor errors in the labels of the XRD patterns of cement and micro-silica presented in Figs. 1 and 2, which have been corrected in the figures included here. In addition, due to concerns over the reliability of the XRD pattern of pumice shown in Fig. 9, as caused by a low signal count, the authors have re-analyzed the pumice and the updated XRD pattern has been included here. It is worth noting that these changes do not affect any of the conclusions. The authors would like to apologise for any inconvenience caused. © 2021  

In this paper, we propose an efficient secure data aggregation scheme for the smart grid, which supports both lossy and lossless data aggregation. In order to reduce the computational overhead of the control center, our proposed model includes a number of entities, called gateways, which act as intermediaries between the users and the control center. At the end of each measurement interval, each user generates a report which is encrypted using the Paillier cryptosystem and contains the user's consumption amount during the previous measurement interval as well as his or her prediction of consumption during another interval in the future. After receiving the user's reports, gateways perform... 

In recent years, determining the common information privately and efficiently between two mutually mistrusting parties have become an important issue in social networks. Many Private set intersection (PSI) protocols have been introduced to address this issue. By applying these protocols, two parties can compute the intersection between their sets without disclosing any information about components that are not in the intersection. Due to the broad range of computational resources that the cloud can provide for its users, determining the set intersection by cloud may decrease the computational cost of the users. The proposed protocol by Abadi et al. is one of the introduced protocols in this... 

The authors regret that there was an error in the SEM image presented in Fig. 4(c) of the previously print version of the article. Please refer to the corrected SEM image as presented here. It is noteworthy that this change does not affect any of the conclusions. The authors would like to apologise for any inconvenience caused. © 2021 Elsevier Ltd  

Copper slag (CS) is an industrial by-product, which is commonly disposed in engineered landfills. Prior studies have successfully incorporated CS as an aggregate phase in cementitious materials. However, the alkali-activated material (AAM) incorporating CS has been scarcely studied. Specifically, the elevated temperature behavior of AAM with CS has not been investigated previously. The present paper aims to study the effects of elevated temperature treatment on the mass loss and residual strength of alkali-activated slag mortars incorporating 0–100% (by volume) of CS with an incremental step of 20% instead of natural sand. The mass loss, compressive and flexural strengths, and microstructure... 

Alkali-activated slag (AAS) binder has been recognized as a suitable material for construction applications owing to its low carbon footprint and good mechanical and durability performance. As a promising alternative to the conventional Portland cement binder, it is important to maximize the performance of AAS composites under normal and harsh environmental conditions such as exposure to fire. The use of fibers in a brittle matrix is a well-known approach to enhance the mechanical strength and cracking behavior under thermal loading. In this study, polypropylene fiber (PPF), glass fiber (GF), and basalt fiber (BF) are used at volume fractions of 0.5%, 1%, and 1.5% in AAS mortar mixes. First,... 

The objective of this work is making comparison between thermodynamic models and data-driven techniques accuracy in prediction of hydrate formation pressure as a function of temperature and composition of gas mixtures. The Peng-Robinson (PR) and Patel-Teja (PT) equations of state are used for thermodynamic modeling and Artificial Neural Networks (ANNs) and Adaptive Neuro-Fuzzy Inference System (ANFIS) are used as data-driven models. The capability of each method is evaluated by comparison with the experimental data collected from literature. It is shown that there is a good agreement between thermodynamic modeling and the experimental data in most of the cases; however, the prediction...