Papers by Ahmad Tawfiq Karimi
arXiv (Cornell University), Jun 1, 2014
To counter a general belief that all the paradoxes stem from a kind of circularity (or involve so... more To counter a general belief that all the paradoxes stem from a kind of circularity (or involve some self-reference, or use a diagonal argument) Stephen Yablo designed a paradox in 1993 that seemingly avoided self-reference. We turn Yablo's paradox, the most challenging paradox in the recent years, into a genuine mathematical theorem in Linear Temporal Logic (LTL). Indeed, Yablo's paradox comes in several varieties; and he showed in 2004 that there are other versions that are equally paradoxical. Formalizing these versions of Yablo's paradox, we prove some theorems in LTL. This is the first time that Yablo's paradox(es) become new(ly discovered) theorems in mathematics and logic.
arXiv (Cornell University), May 13, 2022
We present an algorithmic approach to estimate the value distributions of random variables of pro... more We present an algorithmic approach to estimate the value distributions of random variables of probabilistic loops whose statistical moments are (partially) known. Based on these moments, we apply two statistical methods, Maximum Entropy and Gram-Charlier series, to estimate the distributions of the loop's random variables. We measure the accuracy of our distribution estimation by comparing the resulting distributions using exact and estimated moments of the probabilistic loop, and performing statistical tests. We evaluate our method on several probabilistic loops with polynomial updates over random variables drawing from common probability distributions, including examples implementing financial and biological models. For this, we leverage symbolic approaches to compute exact higher-order moments of loops as well as use sampling-based techniques to estimate moments from loop executions. Our experimental results provide practical evidence of the accuracy of our method for estimating distributions of probabilistic loop outputs.
Computer Engineering and Applications Journal, 2016
Multicasting is a service for disseminating data to a group of hostsand it is of paramount import... more Multicasting is a service for disseminating data to a group of hostsand it is of paramount importance in applications with a close collabo-ration of network hosts. Due to limited energy available in the wirelessdevices, energy management is one of the most important problems inwireless networks. Energy aware routing strategies help us to mini-mize the energy costs for communication as much as possible and toincrease the network lifetime. In this paper, we address the problemof energy efficient routing to increase the lifetime of the network. Wepresent three new strategies for online multicast energy aware routingin wireless networks to increase the network lifetime.
1. Young researchers club, Urmia Branch, Islamic Azad University 2. Full Professor of Agriculture... more 1. Young researchers club, Urmia Branch, Islamic Azad University 2. Full Professor of Agriculture Department, Faculty of Agriculture Urmia University 3. Asistant Professor of Agriculture Department, Faculty of Agriculture Urmia University 4. Researcher in Agriculture and Natural Resources Research Center of Western Azerbaijan,Urmia-Iran 5. Young researchers club, khoy Branch, Islamic Azad University Corresponding email: Ahmad_karimi@hotmail.com
Computer Methods in Applied Mechanics and Engineering, 2021
Optimal design of electronic devices such as sensors is essential since it results in more accura... more Optimal design of electronic devices such as sensors is essential since it results in more accurate output at the shortest possible time. In this work, we develop optimal Bayesian inversion for electrical impedance tomography (EIT) technology in order to improve the quality of medical images generated by EIT and to put this promising imaging technology into practice. We optimize Bayesian experimental design by maximizing the expected information gain in the Bayesian inversion process in order to design optimal experiments and obtain the most informative data about the unknown parameters. We present optimal experimental designs including optimal frequency and optimal electrode configuration, all of which result in the most accurate estimation of the unknown quantities to date and high-resolution EIT medical images, which are crucial for diagnostic purposes. Numerical results show the efficiency of the proposed optimal Bayesian inversion method for the EIT inverse problem. c
The main goal of this paper is to develop the forward and inverse modeling of the Coronavirus (CO... more The main goal of this paper is to develop the forward and inverse modeling of the Coronavirus (COVID-19) pandemic using novel computational methodologies in order to accurately estimate and predict the pandemic. This leads to governmental decisions support in implementing effective protective measures and prevention of new outbreaks. To this end, we use the logistic equation and the SIR system of ordinary differential equations to model the spread of the COVID-19 pandemic. For the inverse modeling, we propose Bayesian inversion techniques, which are robust and reliable approaches, in order to estimate the unknown parameters of the epidemiological models. We use an adaptive Markov-chain Monte-Carlo (MCMC) algorithm for the estimation of a posteriori probability distribution and confidence intervals for the unknown model parameters as well as for the reproduction number. Furthermore, we present a fatality analysis for COVID-19 in Austria, which is also of importance for governmental p...
Computer Methods in Applied Mechanics and Engineering, 2020
We develop an electrical-impedance tomography (EIT) inverse model problem in an infinite-dimensio... more We develop an electrical-impedance tomography (EIT) inverse model problem in an infinite-dimensional setting by introducing a nonlinear elliptic PDE as a new EIT forward model. The new model completes the standard linear model by taking the transport of ionic charge into account, which was ignored in the standard equation. We propose Bayesian inversion methods to extract electrical properties of inhomogeneities in the main body, which is essential in medicine to screen the interior body and detect tumors or determine body composition. We also prove well-definedness of the posterior measure and well-posedness of the Bayesian inversion for the presented nonlinear model. The new model is able to distinguish between liquid and tissues and the state-of-the-art delayed-rejection adaptive-Metropolis (DRAM) algorithm is capable of analyzing the statistical variability in the measured data in various EIT experimental designs. This leads to design a reliable device with higher resolution images which is crucial in medicine for diagnostic purposes. We first test the validation of the presented nonlinear model and the proposed inverse method using synthetic data on a simple square computational domain with an inclusion. Then we establish the new model and robustness of the proposed inversion method in solving the ill-posed and nonlinear EIT inverse problem by presenting numerical results of the corresponding forward and inverse problems on a real-world application in medicine and healthcare. The results include the extraction of electrical properties of human leg tissues using measurement data. c
Computers in Biology and Medicine, 2020
We propose a mathematical model based on a system of partial differential equations (PDEs) for bi... more We propose a mathematical model based on a system of partial differential equations (PDEs) for biofilms. This model describes the time evolution of growth and degradation of biofilms which depend on environmental factors. The proposed model also includes quorum sensing (QS) and describes the cooperation among bacteria when they need to resist against external factors such as antibiotics. The applications include biofilms on teeth and medical implants, in drinking water, cooling water towers, food processing, oil recovery, paper manufacturing, and on ship hulls. We state existence and uniqueness of solutions of the proposed model and implement the mathematical model to discuss numerical simulations of biofilm growth and cooperation. We also determine the unknown parameters of the presented biofilm model by solving the corresponding inverse problem. To this end, we propose Bayesian inversion techniques and the delayed-rejection adaptive-Metropolis (DRAM) algorithm for the simultaneous extraction of multiple parameters from the measurements. These quantities cannot be determined directly from the experiments or from the computational model. Furthermore, we evaluate the presented model by comparing the simulations using the estimated parameter values with the measurement data. The results illustrate a very good agreement between the simulations and the measurements.
Logic and Logical Philosophy, 2019
Temporal logic is of importance in theoretical computer science for its application in formal ver... more Temporal logic is of importance in theoretical computer science for its application in formal verification, to state requirements of hardware or software systems. Linear temporal logic is an appropriate logical environment to formalize Yablo's paradox which is seemingly non-self-referential and basically has a sequential structure. We give a brief review of Yablo's paradox and its various versions. Formalization of these paradoxes yields some theorems in Linear Temporal Logic (LTL) for which we give syntactic proofs using an appropriate axiomatization of LTL.
Filozofia Nauki, 2019
Proving a paradox from very weak assumptions helps us to reveal what the source of the paradox is... more Proving a paradox from very weak assumptions helps us to reveal what the source of the paradox is. We introduce a weak non-arithmetical theory in a language of predicate logic and give proofs for various versions of Yablo's paradox in this weak system. We prove Always, Sometimes, Almost Always, and Infinitely Often versions of Yablo's paradox in the presented weak axiom system, which is much weaker than the arithmetical setting.
Journal of Computational Electronics, 2018
This paper presents and evaluates a novel approach based on material implementation to improve th... more This paper presents and evaluates a novel approach based on material implementation to improve the performance of a 1-bit memristor-based full adder. In addition, two new efficient architectures are presented and evaluated for an 8-bit memristorbased full adder, serial memristor-based full adder and parallel-serial memristor-based full adder. Using the proposed approach, the number of required steps to accumulate the sum and carry-out in the proposed serial and parallel-serial 8-bit memristorbased full adder architectures is 168 and 56, respectively. Moreover, the number of required memristors in the proposed serial and parallel-serial memristor-based full adder architectures is 19 and 33, respectively. The evaluation results show that both delay and density are improved in the proposed architectures compared to other memristor-based full adder architectures.
Renewable Energy and Power Quality Journal, 2008
Electricity industry is changing by organizational and legislative evolutions dealing with econom... more Electricity industry is changing by organizational and legislative evolutions dealing with economical and environmental affairs. Besides rapid development in energy generation decreased the related variable costs, considering environmental issues. In this study energy generation technologies are evaluated both from economical and environmental views. Applying Analytical Hierarchy Process (AHP) which is extremely applicable and known as one of the efficient methods to analyze complicated multi criteria problems it is achieved interesting results from evaluation. The main goal of this evaluation which is presented in this essay is to extract total preference weights for generation technology. Total preference weights are determined considering four criteria in fossil fuel power plants and renewable energy resources power plant using this evaluation pattern. For three power plant of gas, steam and combine cycle the total preference weights are calculated by considering seven criteria. For the next eight power plants of wind, small hydro, photovoltaic, solar thermal, micro turbine, biomass, geothermal and fuel cell total preference weights is considered according to seven criteria. Optimum capacity is calculated and determined. Sensitivity analysis is made on two most important criteria of this model named 1-operation and investment cost, and 2-fossil resources scarcity for power plants. 1-Multiple criteria of objective function, 2-possibility of sensitivity analysis on criteria weights and 3-concurrent inspection of qualitative and quantitative criteria in optimization of objective function are three advantages of the proposed model comparing common applying method such as (mono-objective software WASP)
International Journal of Control and Automation, 2017
This study develops and evaluates a novel architecture for class-D CMOS power amplifier. In this ... more This study develops and evaluates a novel architecture for class-D CMOS power amplifier. In this new architecture all stages of class-D amplifier are designed carefully. A second order delta sigma modulation, high switching frequency and three passive feedbacks are used in modulation stage. A special filter is designed to improve the quality of this system. This paper idea is simulated using MATLAB. The simulation results show that the developed class-D CMOS power amplifier architecture has low THD (<0.001), High SNR (>80dB), and high efficiency (>95%), which show that this new architectural design for class-D amplifier has the best performance in terms of THD, and efficiency in comparison with other class-D CMOS power amplifier architectures.
The Critisim of Seyyed Hassan Hosseini’s Poetry from the Viewpoint of Imaginary
Literary Art, Oct 15, 2011
Abstract Imagery is indirect expression of covert meaning beyond the words and classic poets are ... more Abstract Imagery is indirect expression of covert meaning beyond the words and classic poets are informed of the valve of the appropriate, timely and suitable image processing. Seyyed Hossan Hosseini's is work from the point of view of Imagery. In this paper, it is tried to be analyzed imagery in poet's collections, on the basis of elements including: similie, metaphor, symbol, metonymy, figure, paradox, synaeshesia.In the simile part, in seyyed Hassan Hosseini's works, detailed and eloguent simile, works detailed, eloguent simile and sensational have much frequency. On the basis of topic, tenor is often the poet, himself/herself, the poet's hero/heroine and abstract elements and from the point of view of vehicle, natural elements, objects, animals, religious, national elements and nearly abstract elements are rarely used.Among the various kinds of metaphors, ironic and explicit metaphors have high frequency and also, in personification, the poet has noted the abstract concepts and used them increasingly. His constructive elements of imagination, from the point of view of vehicle, are generally natural elements, objects, animals, and images related to eternal God, poet and his/her characteristics, religion, prophet and the hosehold of the prophet of Islam, the images related to revolution, war and martyr that organize the constructive elements of imagination from the point of view of tenor. The poet in all of his works has used the figurative documents. In the part of the symbols, Seyyed Hassan Hosseini, has used the three sources of symbol, that is, nature, national, mythological customs and religion, but more than all he has used nature for presentation of images and expressing of his feeling. The applied symbols in his poetries are generally conventional and customary. The application of elements of nature in the position of symbol has led to forming of social symbolism in his works. Almost all of the available metonymies in poet's works in the point of view of vehicle, current metonymy and from the point of [...]
Apple peel waste as a natural antioxidant for heat-stressed broiler chickens
Tropical Animal Health and Production, 2016
This study was conducted to evaluate the effects of processed apple peel waste (APW), alone or in... more This study was conducted to evaluate the effects of processed apple peel waste (APW), alone or in combination with an enzyme, as a natural antioxidant on broiler chickens under heat stress. A total of 360 unsexed, 28-day-old broilers were assigned to 6 dietary treatments with four replicates (15 broilers per pen). The experiment consisted of a 3 × 2 factorial arrangement with three levels of apple peel waste (0, 50 or 100 g/kg of diet) and two levels of enzyme (0 or 500 mg/kg, ZY Multi(®)). Inclusion of 100-g APW/kg of diet decreased broiler weight gain at 42 days of age. Inclusion of 50 and 100-g APW/kg of diet increased gizzard and small intestine weights. Feeding 50 and 100-g APW/kg increased high-density lipoprotein (HDL) cholesterol and decreased low-density lipoprotein (LDL) cholesterol and malondialdehyde in blood serum at 49 days of age. At 49 days of age, apparent ileal protein digestibility was reduced when 50 and 100-g APW/kg were used in the diet. This study showed that feeding APW up to 50 g/kg from 28 to 49 days of age increased HDL cholesterol and decreased LDL cholesterol in serum and had no adverse effect on broiler performance.
Revista Brasileira de Ciência Avícola, 2012
A study was conducted to evaluate the combined effects of garlic, oyster mushroom and propolis ex... more A study was conducted to evaluate the combined effects of garlic, oyster mushroom and propolis extract on the growth performance, organ weights, antibody response to Newcastle Disease Virus (NDV), serum lipid concentrations and nutrient digestibility of male broilers. A total of 192 day old chicks (Ross 308) were randomly assigned to 3 treatments with 4 replications (16 birds per replication). Experimental treatments were a maize-soybean based diet as control, control diet supplemented with a combination of garlic (30 g/kg), oyster mushroom (2 g/kg) and propolis extract (0.2 g/kg) known as GMP, and control diet supplemented with Virginamycin (0.25 g/kg) as antibiotic. The inclusion of GMP decreased (p < 0.05) live body weight, average daily gain and feed intake but had no effect on feed conversion ratio when compared to control diet. GMP and antibiotic had no effects on relative weight of organs. Antibiotic decreased (p < 0.05) the relative weight of small intestine segments. GMP decreased total cholesterol but did not affect other serum lipids when compared to control group. Antibiotic increased (p < 0.05) cholesterol concentration in serum. The inclusion of GMP to the diet improved antibody response to NDV when compared to control and antibiotic diets. In conclusion, the results showed that GMP decreased growth performance but improved immunity of broiler chickens. More studies should be performed to confirm the action modes of such combinations.
Determination and Allocation of Reactive Power Cost Using Developed Tracing Method
ABSTRACT Abstract - Conventional methods of determining and allocating of reactive power costs wh... more ABSTRACT Abstract - Conventional methods of determining and allocating of reactive power costs which are based on power factor, do not provide an accurate method to consumers reactive power pricing. While support for ensuring proper and continuous reactive power is needed to generate sufficient incentives to generate reactive power. To motivate participates, it is needed to create an economic structure of reactive power. In this paper, a method for determining the cost of reactive power is presented considering direct and indirect costs in generating and transmission. The developed tracing method for allocating reactive power cost is introduced. Simulation results in the IEEE 30-bus test system are considered to test and validate the proposed method. The methodologies, results and discussion presented in this paper show that the presented method is practical and has reasonable speed for determination and allocating reactive power cost.
The Journal of Poultry Science, 2007
The interaction between chick type and xylanase supplementation (Avizyme +-**) of a wheat based d... more The interaction between chick type and xylanase supplementation (Avizyme +-**) of a wheat based diet was investigated using a-ῌ, factorial arrangement. The diet (0./ g wheat/kg) was supplemented with * or + g/kg xylanase and fed to broilers, broiler breeders, or pullets from + to +3 day-old. The basal diet was formulated based on the average of the nutrient requirements of all bird types investigated. Body weight, feed intake, feed: gain ratio, upper intestinal digesta content viscosity, and relative weights of gastrointestinal organs to body weight were determined. There were significant e#ects of chick type on live weight, daily gain, feed intake, and feed: gain ratio (P῍*.*+). During the course of this study, pullets always showed significantly lower body weight, feed intake, daily gain, and higher feed: gain ratio (P῍*.*/). The e#ect of enzyme supplementation on body weight, daily gain, and feed: gain was significant only at later age growth periods (P ῍*.*/). The positive e#ect of enzyme inclusion was only pronounced in broiler chicks. Daily feed intake was not significantly a#ected by enzyme supplementation of the diets (P῎*.*/). Small intestinal digesta content viscosity was not di#erent between di#erent chick classes (P῎*.*/), but enzyme inclusion significantly (P῍ *.*/) decreased digesta viscosity in all three chick types. Gastrointestinal tract characteristics were only a#ected by chick type (P῍*.*/). It was concluded that while performance di#erences between chick types were large as expected, the e#ect of enzyme supplementation on performance was dependent both on chick type and age. The reduction of intestinal digesta viscosity due to enzyme supplementation is not a reliable gauge of the positive enzyme e#ect observed on bird performance when compared across di#erent classes of chicks.
Background and Objectives: In arid and semi-arid regions, wastewater reuse has become an importan... more Background and Objectives: In arid and semi-arid regions, wastewater reuse has become an important element in agriculture. However, irrigation with this resource can be either beneficial or harmful, depending on the wastewater characteristics. The aim of this research was to investigate the soil bacterial and crops quality irrigated with treated wastewater. Material and Methods: This research was conducted on a maize field near the wastewater treatment plant in Shahr-e-kord in summer,2011. Plots were arranged in a randomized complete block design in 3 replications and 2 treatments, well water (W1) with fertilizer and effluent (W2). Results: At the end of growth season, soil samples were collected from depth of 0-5 and 5-15 cm and plant samples consisting of old and new leaves and seeds were collected for bacteriological analysis. According to bacteriological analysis, total number of positive lactose bacteria, total and fecal coliforms in depth of 0-5 cm was 42% more than depth of 5-15 cm. In the case of old leaves, total number of coliform and fecal coliform was 88 and 40 MPN/100 mL respectively. Moreover, for new leaves, it was 38 and 2 MPN/100 ml respectively. Conclusion: According the results, number of indicator bacteria in soil is decreased (about 35%) by passing time.
Using Genetic Algorithm for Social Welfare Maximization in Deregulated Power Markets by Optimal Locating and Sizing of TCSC
ABSTRACT Series FACTS devices such as TCSC, with its ability to directly control the power flow c... more ABSTRACT Series FACTS devices such as TCSC, with its ability to directly control the power flow can be very effective to improve the operation of transmission network. In this paper, corrective solution for congestion management by using TCSC has been reviewed. A novel genetic algorithm for finding the optimal location and size of this device was proposed for congestion management with the aim of increasing social welfare while cost of TCSC was incorporated. The simulation results were successfully tested on IEEE 14-bus system. Analyzing the results with and without FACTS devices confirms that these devices are appropriate for long time congestion management.
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Papers by Ahmad Tawfiq Karimi