Sharif Digital Repository

Agent oriented methodologies have become one of the most important issues of software development. Several methodologies have been proposed to guide developers through various stages of agent based system development. Deciding which methodology to be selected in a specific case is a critical problem. This paper presents a quantitative approach to evaluate complexity of agent oriented methodologies due to dependency of stages and phases. This framework focuses on the lifecycle of a methodology and relations between its stages. The proposed models of the methodology and overall process of its lifecycle is discussed thoughtfully and the complexity of the entire methodology lifecycle is... 

Kinetic and morphological aspects of slurry propylene polymerization using a MgCl2-supported Ziegler-Natta catalyst synthesized from a Mg(OEt)2 precursor in the presence and absence of two different external donors are investigated. The kinetic profiles show similar trend in presence and absence of donors. The Mg(OEt)2-based catalyst show a mild activation and a long-standing activity with good replication of the catalyst particles. The results show that synthesized Mg(OEt)2-based Ziegler-Natta catalyst presents a highly stable polymerization activity and good replication due to the uniform Ti distribution all over the catalyst particles. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim  

Thin films of Fe73.1Cu1Nb3.1Si14.7B8.2 alloy with 200, 500, and 800 nm thicknesses have been deposited by RF sputtering. Their magnetic properties have been characterized using Alternating Gradient Field Magnetometer (AGFM) and Vibrating Sample Magnetometer (VSM). The effects of residual stresses investigated by nanoindentation experiments were conducted on the as-deposited samples. It is observed that the coercivity of as-deposited films is inversely proportional to the thickness in relation with the residual stress induced during sputtering. © 2017 Sharif University of Technology. All rights reserved  

The paper aims at investigating the microstructure, failure mode transition, peak load and energy absorption of DP600 dual phase steel during the tensile-shear test. It was found that the welding current has profound effect on the load–displacement characteristics. In the low welding current, welds failed in interfacial failure mode. Increasing welding current resulted in sufficient weld nugget growth to promote double-sided pullout failure mode with improved mechanical properties. Further increase in the welding current caused expulsion and failure mode was changed to single-sided pullout with reduced energy absorption capability. It was found that the fusion zone size is the key parameter... 

Once in biological fluids, the surface of nanoparticles (NPs) is rapidly covered with a layer of biomolecules (i.e., the "protein corona") whose composition strongly determines their biological identity, regulates interactions with biological entities including cells and the immune system, and consequently directs the biological fate and pharmacokinetics of nanoparticles. We recently introduced the concept of a "personalized protein corona" which refers to the formation of different biological identities of the exact same type of NP after being exposed to extract plasmas from individuals who have various types of diseases. As different diseases have distinct metabolomic profiles and... 

Presents information on global MTTS society education initiatives. © 2000-2012 IEEE  

Due to high surface to volume ratio and tunable band gap, two dimensional (2D) layered materials such as MoS2, is good candidate for gas sensing applications. This research mainly focuses on variation of Density of States (DOS) of MoS2 monolayes caused by ethanol adsorption. The nanosheets are synthesized by liquid exfoliation, and then using Scanning Tunneling Spectroscopy (STS) and Density Functional Theory (DFT), local electronic characteristic such as DOS and band gap in non-vacuum condition are analyzed. The results show that ethanol adsorption enhances DOS and deform orbitals near the valence and conduction bands that increase transport of carriers on the sheet. © 2018 IOP Publishing... 

In future wireless networks, network functions virtualization lays the foundations for establishing a new dynamic resource management framework to efficiently utilize network resources. In this paper, a network service can be viewed as a chain of virtual network functions (VNFs), called a service function chain (SFC), served via placement, admission control (AC), and embedding into network infrastructure, based on the resource management objectives and the state of network. To fully exploit such a potential and reach higher network performance, resource management stages should be jointly performed. To this end, two main challenges are: how to present a system model that formulates the... 

Gating of mechanosensitive (MS) channels is driven by a hierarchical cascade of movements and deformations of transmembrane helices in response to bilayer tension. Determining the intrinsic mechanical properties of the individual transmembrane helices is therefore central to understanding the intricacies of the gating mechanism of MS channels. We used a constant-force steered molecular dynamics (SMD) approach to perform unidirectional pulling tests on all the helices of MscL in M. tuberculosis and E. coli homologs. Using this method, we could overcome the issues encountered with the commonly used constant-velocity SMD simulations, such as low mechanical stability of the helix during... 

Tetra-coordinated copper(II) complexes, [CuL2] and [Cu(phox)2], were synthesized by reaction of 1-((4-bromophenylimino)methyl)naphthalen-2-ol, HL, and 2-(2′-hydroxyphenyl)-2-oxazoline, Hphox, ligands with copper acetate, respectively. The complexes were characterized using FT-IR spectroscopy, elemental analyses, and their solid state structures were confirmed by single crystal X-ray diffraction. The catalytic activity of the complexes was evaluated in one-pot azide–alkyne cycloaddition (AAC) click reaction in water without need of any additional agent. The [CuL2] complex showed high catalytic activity in this reaction‌‌‌ and 1,2,3-triazole derivatives were produced in moderate to good... 

We carried out molecular dynamics simulations (MD) to investigate the adsorption of calcium chloride (CaCl2) at n-hexane-water interfaces. We also measured the interfacial tensions (IFT) of the selected systems making use of the pendant-drop method. The histograms of hexane, water, and the ions indicate an electrical double layer (EDL) near the interface. The trend of the EDL indicates that chloride anions intend to adsorb to the interface more intrinsically than calcium cations. The measured interfacial width of the n-hexane-water interfaces decreases with the salt concentration. The average densities of the interfacial and bulk aqueous solutions demonstrate density heterogeneity in the... 

Terahertz spectroscopy is a useful and an efficient method for detection of pure materials and also mixture compounds. In the present study the terahertz spectra of the α-lactose, high explosives RDX and also the binary mixture of mentioned materials has been obtained in the transition mode. The obtained spectra of the pure materials were in a very good agreement with literatures in the range of 0.1 to 1.5 terahertz. The spectra of mixture samples which show the specific fingerprint characters of each component, declare that terahertz spectroscopy can be used effectively for the detection of explosives and chemical compounds even in the mixture samples. © 2016 IEEE  

Response spectra of fixed offshore structures impacted by extreme waves are investigated based on the higher order components of the nonlinear drag force. In this way, steel jacket platforms are simplified as a mass attached to a light cantilever cylinder and their corresponding deformation response spectra are estimated by utilizing a generalized single degree of freedom system. Based on the wave data recorded in the Persian Gulf region, extreme wave loading conditions corresponding to different return periods are exerted on the offshore structures. Accordingly, the effect of the higher order components of the drag force is considered and compared to the linearized state for different sea... 

Providing backhaul connectivity for macro and pico base stations (BSs) constitutes a significant share of infrastructure costs in future heterogeneous networks (HetNets). To address this issue, the emerging idea of flexible backhaul is proposed. Under this architecture, not all the pico BSs are connected to the backhaul, resulting in a significant reduction in the infrastructure costs. In this regard, pico BSs without backhaul connectivity need to communicate with their nearby BSs in order to have indirect accessibility to the backhaul. This makes the radio resource management (RRM) in such networks more complex and challenging. In this paper, we address the problem of cross-layer RRM in... 

Cu2O nanocubes, octahedra, spheres and truncated rhombic dodecahedral were prepared and their structural, morphological, and electronic properties were investigated by X-ray diffraction analysis, X-ray absorption near edge structure, scanning electron microscope and transmission electron microscope and X-ray absorption near edge structure. Cu2O nanocrystals were successfully employed to catalyze the 1,3-dipolar cycloaddition reaction for the synthesis of 1,4-disubstituted triazoles. Cu2O nanocubes and octahedral showed the superior catalytic performance in the cycloaddition reaction. These results reveal that crystal-plane engineering of oxide catalysts is a useful strategy for developing... 

We decorated Zn-doped TiO2-nanoparticle-based photoanodes with carbon nanotube (CNT)-derived TiO2 nanotubes (TNs) to enhance the power conversion efficiency of dye-sensitized solar cells (DSCs). X-ray photoelectron spectroscopy analysis verified that Zn ions, in the range of 0 to 1 at %, were successfully doped into the TiO2 lattice. Field-emission SEM and TEM images of the TNs, as derived from the sol–gel template-assisted route, revealed that a uniform TiO2 coating with a thickness of 60 to 120 nm was deposited on the surface of the CNT template through a noncovalent route. We observed that the cell efficiency improved from 6.80 for pure TiO2 to 7.52 for 0.75 at % Zn-doped TiO2... 

Methods for the regioselective C-H borylation and subsequent cross-coupling of the 2,1-borazaronaphthalene core are reported. Azaborines are dependent on B-N/C=C isosterism when employed in strategies for developing diverse heterocyclic scaffolds. Although 2,1-borazaronaphthalene is closely related to naphthalene in terms of structure, the argument is made that the former has electronic similarities to indole. Based on that premise, iridium-mediated C-H activation has enabled facile installation of a versatile, nucleophilic coupling handle at a previously inaccessible site of 2,1-borazaronaphthalenes. A variety of substituted 2,1-borazaronaphthalene cores can be successfully borylated and... 

In this article, experimental and numerical investigations are performed to study a thermogravitational column (TGC) for the separation of toluene/n-heptane mixture. This research has tried to determine the main significant parameters and their effects on the performance of the process. In experimental examinations, the influence of the main parameters such as feed flow rate, cut and temperature gradient on the performance of the TGC efficiency is studied. In addition, computational fluid dynamics is used to simulate the separation process in this review. The response surface methodology (RSM) was also applied to minimize the number of runs and investigate the optimum operating conditions.... 

In this paper, we present a numerical simulation of a laminar, steady and Newtonian flow of f-graphene nanoplatelet/water nanofluid in a new microchannel design with factors for increasing heat transfer such as presence of ribs, curves to enable satisfactory fluid mixing and changing fluid course at the inlet and exit sections. The results of this study show that Nusselt number is dependent on nanoparticles concentration, inlet geometry and Reynolds number. As the nanofluid concentration increases from 0 to 0.1% and Reynolds number from 50 to 1000, the Nusselt number enhances nearly up to 3% for increase in fluid concentration and averagely from 15.45 to 54.1 and from 14.5 to 55.9 for... 

Autism spectrum disorder (ASD) includes different neurodevelopmental disorders characterized by deficits in social communication, and restricted, repetitive patterns of behavior, interests or activities. Based on the importance of early diagnosis for effective therapeutic intervention, several strategies have been employed for detection of the disorder. The artificial neural network (ANN) as a type of machine learning method is a common strategy. In the current study, we extracted genomic data for 487 ASD patients and 455 healthy individuals. All individuals were genotyped in certain single-nucleotide polymorphisms within retinoic acid-related orphan receptor alpha (RORA), gamma-aminobutyric...