Sharif Digital Repository

Since the injection of the oncolytic viruses in the virotherapy process reduces the toxicity and drug resistance inherent in the chemotherapy; chemovirotherapy as a novel combination therapy has become an efficient cancer treatment. The primary purpose of this paper is to design a robust optimal control strategy for the chemovirotherapy through which the tumor density decreases to its stable condition with limited drug and virus delivery. This desired treatment should be responsive in the presence of input disturbances and parametric uncertainties. In this regard, an ODE (Ordinary Differential Equation) mathematical model of the chemovirotherapy process presenting the connection between the... 

Best cancer treatment is the one which reduces the tumor's density in minimum time with less side effects, considering the input limitations. In this paper, a tracking controller was designed to achieve the mentioned objectives, simultaneously. An ordinary differential equations (ODEs)-based mathematical model of a human's body under chemovirotherapy was selected, which includes the uninfected and infected tumor cells, free viruses, immune cells, and a chemotherapeutic drug. Stability analysis was used to determine the sensible equilibrium points. For tracking purposes, a servo controller based on the entire eigenstructure assignment (EESA) approach was applied to the model, continuously and... 

In this study the ability of artificial neural network (ANN) in forecasting the daily NASDAQ stock exchange rate was investigated. Several feed forward ANNs that were trained by the back propagation algorithm have been assessed. The methodology used in this study considered the short-term historical stock prices as well as the day of week as inputs. Daily stock exchange rates of NASDAQ from January 28, 2015 to 18 June, 2015 are used to develop a robust model. First 70 days (January 28 to March 7) are selected as training dataset and the last 29 days are used for testing the model prediction ability. Networks for NASDAQ index prediction for two type of input dataset (four prior days and nine... 

In this paper a new least mean square (LMS) based adaptive weighting algorithm is proposed. It is appropriate for antenna array systems with moving targets and mobile applications. The essential goal of this algorithm is to reduce the complexity of weighting process and to decrease the time needed for adjusting the antenna radiation pattern. The main lobe of antenna will be adjusted in the direction of desired signal (main signal) and nulls pointed in the direction of undesired signals (interference signals). By predicting the relative velocity of source, the next location of the source will be estimated and the array weights will be determined using LMS algorithm before arriving to the new... 

Reducing the computational complexity as well as convergence time is the main task of adaptive antenna array processing. This article proposes an improved algorithm for estimating the weights of adaptive array elements based on Constant Modulus Algorithm (CMA). In this new type of algorithm, those weights that have higher effect on the radiation pattern will be estimated and antenna pattern will be adjusted by changing these weights. In this research, 3 new algorithms are proposed. By simulating these algorithms and comparing them with conventional full weight CMA, finally new algorithm that has a reduced complexity and an acceptable performance at different signal to noise ratios (SNRs) is... 

Background: Gestational Diabetes Mellitus (GDM) is a health problem that is increasing around the world. Introduction: Prevention of GDM, rather than treatment, could have several benefits in terms of both health and economic cost. Even a slight reduction in maternal glucose in non-diabetic women, particularly in women at high risk for GDM, may have significant benefits for pregnancy results and the future health of off-springs. Probiotics are a relatively new intervention, which are assessed by mothers’ metabolism, and can reduce blood sugar levels, prevent gestational diabetes and reduce the maternal and fetal complications resulting from it. The aim of this study was to review the studies... 

In this paper, a confined infill panel previously experimented under out-of-plane loading is modeled and analyzed by the dynamic explicit method (DEM). This method is shown to have a good estimation of the experimental results, and is thus adopted to investigate the out-of-plane behavior of an infill model. Based on the analytical results, the stress distribution of an infill panel prior to and after cracking, and the effect of an arching mechanism on post-cracking behavior, is studied. A semi-empirical relationship is accordingly developed for predicting the transverse resistance of masonry infills due to one-way arching action, which accounts for the effects of the boundary frame... 

We introduce a new robust simulation optimization method in which the probability of occurrence of uncertain parameters is considered. It is assumed that the probability distributions are unknown but historical data are on hand and using φ-divergence functionality the uncertainty region for the uncertain probability vector is defined. We propose two approaches to formulate the robust counterpart problem for the objective function estimated by Kriging. The first method is a minimax problem and the second method is based on the chance constraint definition. To illustrate the methods and assess their performance, numerical experiments are conducted. Results show that the second method obtains... 

In this article, a new algorithm for rather expensive simulation problems is presented, which consists of two phases. In the first phase, as a model-based algorithm, the simulation output is used directly in the optimization stage. In the second phase, the simulation model is replaced by a valid metamodel. In addition, a new optimization algorithm is presented. To evaluate the performance of the proposed algorithm, it is applied to the (s,S) inventory problem as well as to five test functions. Numerical results show that the proposed algorithm leads to better solutions with less computational time than the corresponding metamodel-based algorithm. © 2017 Taylor & Francis Group, LLC  

There are many steel structures in Iran with semi-rigid saddle connections. It has been observed that, during a strong earthquake, this type of connection can experience a premature fracture, which will endanger the stability of the structure. The present study endeavored to improve the mechanical characteristics including the initial stiffness, yield moment, maximum moment, crack rotation, and load transfer mechanisms of the conventional saddle connections using retrofitting methods. An experimental study was conducted on six full-scale specimens to study the effect of the retrofitting methods on the stiffness, yield moment, and maximum moment of the connection and for the prevention of... 

Results of the seismic performance assessment of a new structural system that has been used in a 54-story reinforced concrete building are presented. The structure, which is still under construction, and has a 'Y-shape' form, utilizes a special structural system that does not include any beams or columns. Instead, walls and slabs are used for carrying both gravitational and lateral loads. The general distinctions of the system are discussed. The structural efficiency of the system is compared with other conventional systems in some existing tall buildings. The seismic responses and dynamic behavior of the structure that were achieved by conducting various analyses are presented. The effects... 

This paper presents a simulation-based study of the delay fault testing in CMOS logic circuits. A novel built-in self-test (BIST) technique is presented for detecting delay faults in this logic family. This scheme does not need test-pattern generation, and thus can be used for robust on-line testing. Simulation results for area, delay, and power overheads are presented. © 2007 IEEE  

This paper investigates the potentialities of the pushover analysis to estimate the seismic deformation demands of concentrically braced steel frames. Reliability of the pushover analysis has been verified by conducting nonlinear dynamic analysis on 5, 10 and 15 story frames subjected to 15 synthetic earthquake records representing a design spectrum. It is shown that pushover analysis with predetermined lateral load pattern provides questionable estimates of inter-story drift. To overcome this inadequacy, a simplified analytical model for seismic response prediction of concentrically braced frames is proposed. In this approach, a multistory frame is reduced to an equivalent shear-building... 

This paper presents a new method for optimization of the dynamic response of structures subjected to seismic excitation. This method is based on the concept of uniform distribution of deformation. In order to obtain the optimum distribution of structural properties, an iterative optimization procedure has been adopted. In this approach, the structural properties are modified so that inefficient material is gradually shifted from strong to weak areas of a structure, This process is continued until a state of uniform deformation is achieved. It is shown that, in general, for a MDOF structure, there exists a specific pattern for distribution of structural properties that results in an optimum... 

Saddle connections are semi-rigid connections that are widely used in Iran. Many existing buildings contain this type of connection. The present study conducted full-scale experiments and used extensive numerical modeling to study the mechanical characteristics of saddle connections. The mechanical characteristics examined were the moment-transfer mechanism, initial stiffness, yield moment, maximum moment, and fracture rotation. The configuration and dimensions of the experimental and numerical specimens were chosen to be similar to those of saddle connections in existing buildings. A parametric study was conducted to determine the factors affecting the mechanical characteristics of these...