Sharif Digital Repository

In this paper application of Ionic Polymer Metal Composite (IPMC) as actuator in a deformable ring capable of locomotion is studied. Such a deformable ring moves as a result of gravitational force acting on its body when its shape changes. It can be used in exploration, search and rescue missions in future, where using conventional robots with rigid bodies and actuators is impossible. Large deformation induced by small stimulating voltage, low stiffness the sensing characteristics that in future work can be used in feedback control make IPMC a good choice for such an application. In this work first a model for IPMC is introduce that can be used in simulating deformation of IPMC in different... 

This article presents a nonlocal sinusoidal shear deformation beam theory (SDBT) for the nonlinear vibration of single-walled boron nitride nanotubes (SWBNNTs). The surrounding elastic medium is simulated based on nonlinear Pasternak foundation. Based on the nonlocal differential constitutive relations of Eringen, the equations of motion of the SWBNNTs are derived using Hamilton's principle. Differential quadrature method (DQM) for the nonlinear frequency is presented, and the obtained results are compared with those predicted by the nonlocal Timoshenko beam theory (TBT). The effects of nonlocal parameter, vibrational modes, length, and elastic medium on the nonlinear frequency of SWBNNTs... 

We prepared porous silicon samples coated by continuous palladium layer in electroless process. Scanning electron microscopy (SEM) showed cauliflower-shape Pd clusters on the surface. I–V curves of Schottky like Pd/porous Si samples were measured in air and in hydrogen. These measurements showed a metal–interface–semiconductor configuration rather than an ideal Schottky diode. Variations of the electrical current in the presence of diluted hydrogen at room temperature revealed that the samples can sense hydrogen in a wide range of concentration (100–40,000 ppm) without any saturation behavior. Hydrogen sensing properties of these samples were investigated at room temperature for a duration... 

In this paper application of ionic polymermetal composite (IPMC) as an actuator in a deformable circular robot is studied. Large bending deformation induced by small stimulating voltage, low stiffness and the sensing characteristics that in future work can be used in feedback control make IPMC a good choice for such an application. Here, first a model for IPMC is proposed that can be used in simulating different arrangements of actuators. The parameters of the model are determined using results of blocked force and free displacement tests. Using this model, potentials of an IPMC-made ring-like robot in passing obstacles and the effect of the number of segments on the rings performance are... 

Despite being the most widely prescribed and misused type of medication, opioids continue to function as robust pain relief agents; however, overdosing is a significant cause of fatalities among opioid users. The δ-opioid receptor (DOR) has immense promise in treating long-term pain by producing anxiolytic and antidepressant-like outcomes. Although DOR agonists play a crucial role, their clinical implementation is restricted because of the probable manifestation of severe, life-threatening complications. A Python-based machine learning approach was employed to develop a quantitative structure–activity relationship (QSAR) model in this study. To address this, 4217 compounds and their... 

Objectives: To investigate the effects of competitive and noncompetitive volleyball exercises on the functional performance and motor control of the upper limbs in chronic stroke survivors. Design: Randomized clinical trial. Setting: Outpatient rehabilitation center. Participants: Chronic stroke survivors (N=48). Interventions: Participants were randomly assigned to competitive (n=16) or noncompetitive (n=16) volleyball exercise groups (60min/d volleyball exercise+30min/d traditional rehabilitation, 3d/wk for 7wk) and control group (n=16). Main Outcome Measures: Reach and grasp motor control measures were evaluated through kinematic analysis. Functional outcomes were assessed via Motor... 

Short-term hydrothermal scheduling (STHTS) is a highly non-linear, multi-model, non-convex, and multi-dimensional optimization problem that has been worked upon for about 5 decades. Many research articles have been published in solving different test cases of STHTS problem, while establishing the superiority of one type of optimization algorithm over the type, in finding the near global best solution of these complex problems. This paper presents the implementation of an improved version of a variant of the Particle Swarm Optimization algorithm (PSO), known as Accelerated Particle Swarm Optimization (APSO) on three benchmark test cases of STHTS problems. The adaptive and variable nature of... 

Short term hydrothermal scheduling (STHTS) is a non-linear, multi-modal and very complex constrained optimization problem which has been solved using several conventional and modern metaheuristic optimization algorithms. A number of research articles have been published addressing STHTS using different techniques. This article presents a comprehensive review of research published for solving the STHTS problem in the last four decades. © 2013 IEEE  

This work presents the development of a novel antifungal ternary approach that is eco-friendly, biocompatible, and cost-effective. It consists of Bryum argenteum extract, silver nanoparticles, and healing clay smectite. The research focuses on the green production of silver nanoparticles using an aqueous extract of Bryum argenteum as a stabilizing and reducing agent, as well as the synthesis of clay dispersion and plant extract. The silver nanoparticles were characterized by FTIR, SEM, UV–Vis spectroscopy, and XRD. Using a standard phytochemical screening procedure, the aqueous, ethanolic, and acetonic extracts of Bryum argenteum were subjected to phytochemical screening. Silver... 

In this paper application of Ionic Polymer Metal Composite (IPMC) as actuator in a deformable ring capable of locomotion is studied. Such a deformable ring moves as a result of gravitational force acting on its body when its shape changes. It can be used in exploration, search and rescue missions in future, where using conventional robots with rigid bodies and actuators is impossible. Large deformation induced by small stimulating voltage, low stiffness the sensing characteristics that in future work can be used in feedback control make IPMC a good choice for such an application. In this work first a model for IPMC is introduce that can be used in simulating deformation of IPMC in different... 

Background: Comprehensive and comparable estimates of health spending in each country are a key input for health policy and planning, and are necessary to support the achievement of national and international health goals. Previous studies have tracked past and projected future health spending until 2040 and shown that, with economic development, countries tend to spend more on health per capita, with a decreasing share of spending from development assistance and out-of-pocket sources. We aimed to characterise the past, present, and predicted future of global health spending, with an emphasis on equity in spending across countries. Methods: We estimated domestic health spending for 195...