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A particle swarm optimization approach on economic and economic-statistical designs of MEWMA control charts
, Article Scientia Iranica ; Volume 18, Issue 6 , December , 2011 , Pages 1529-1536 ; 10263098 (ISSN) ; Malaki, M ; Ershadi, M. J ; Sharif University of Technology
2011
Abstract
Control charts are the best tools to monitor main process parameters, and the Multivariate Exponentially Weighted Moving Average, MEWMA, type of this tool is used when there are several correlated quality characteristics to be monitored simultaneously where detecting small deviations of the characteristics is desired. In this paper, the models of both the economic and the economic-statistical design problems of MEWMA control charts are solved by a Particle Swarm Optimization (PSO) approach. The comparison study between the economic and the economic-statistical designs shows better statistical performances of the economic-statistical design with negligible increase in cost. Furthermore, in...
An integrated HFMEA-DES model for performance improvement of general hospitals: A case study
, Article International Journal of Quality and Reliability Management ; 2020 ; Ershadi, M. J ; Akhavan Niaki, S. T ; Sharif University of Technology
Emerald Group Publishing Ltd
2020
Abstract
Purpose: Healthcare failure mode and effect analysis (HFMEA) identifies potential risks and defines preventive actions to reduce the effects of risks. In addition, a discrete event simulation (DES) could evaluate the effects of every improvement scenario. Consequently, a proposed integrated HFMEA-DES model is presented for quality improvement in a general hospital. Design/methodology/approach: In the proposed model, HFMEA is implemented first. As any risk in the hospital is important and that there are many departments and different related risks, all defined risk factors are evaluated using the risk priority number (RPN) for which related corrective actions are defined based on experts'...
An integrated HFMEA-DES model for performance improvement of general hospitals: A case study
, Article International Journal of Quality and Reliability Management ; Volume 38, Issue 1 , 2021 , Pages 1-24 ; 0265671X (ISSN) ; Ershadi, M. J ; Akhavan Niaki, S. T ; Sharif University of Technology
Emerald Group Holdings Ltd
2021
Abstract
Purpose: Healthcare failure mode and effect analysis (HFMEA) identifies potential risks and defines preventive actions to reduce the effects of risks. In addition, a discrete event simulation (DES) could evaluate the effects of every improvement scenario. Consequently, a proposed integrated HFMEA-DES model is presented for quality improvement in a general hospital. Design/methodology/approach: In the proposed model, HFMEA is implemented first. As any risk in the hospital is important and that there are many departments and different related risks, all defined risk factors are evaluated using the risk priority number (RPN) for which related corrective actions are defined based on experts'...
Economic and economic-statistical designs of phase II profile monitoring
, Article Quality and Reliability Engineering International ; Vol. 30, issue. 5 , July , 2014 , pp. 645-655 ; ISSN: 07488017 ; Niaki, S. T. A ; Ershadi, M. J ; Sharif University of Technology
2014
Abstract
In economic design of profiles, parameters of a profile are determined such that the total implementation cost is minimized. These parameters consist of the number of set points, n, the interval between two successive sampling, h, and the parameters of a control chart used for monitoring. In this paper, the Lorenzen-Vance cost function is extended to model the costs associated with implementing profiles. The in-control and the out-of-control average run lengths, ARL0 and ARL1, respectively, are used as two statistical measures to evaluate the statistical performances of the proposed model. A genetic algorithm (GA) is developed for solving both the economic and the economic-statistical...
A hybrid Nelder-Mead simplex and PSO approach on economic and economic-statistical designs of MEWMA control charts
, Article International Journal of Advanced Manufacturing Technology ; Volume 65, Issue 9-12 , 2013 , Pages 1339-1348 ; 02683768 (ISSN) ; Noorossana, R ; Niaki, S. T. A ; Ershadi, M. J ; Sharif University of Technology
2013
Abstract
Economic design of a control chart involves determining its basic parameters such that a cost function is minimized. This design when statistical performance measures are also considered is referred to as the economic-statistical design. In this paper, a simplex-based Nelder-Mead algorithm is used in combination with a particle swarm meta-heuristic procedure to solve both the economic and economic-statistical designs of a MEWMA control chart. The application results on extensive simulation experiments show that the particle swarm can lead the Nelder-Mead algorithm to better results. Furthermore, a comparative study is performed on the performances of three different algorithms of the...
On the scheduling of energy-aware fault-tolerant mixed-criticality multicore systems with service guarantee exploration
, Article IEEE Transactions on Parallel and Distributed Systems ; Volume 30, Issue 10 , 2019 , Pages 2338-2354 ; 10459219 (ISSN) ; Ansari, M ; Ershadi, G ; Hessabi, S ; Sharif University of Technology
IEEE Computer Society
2019
Abstract
Advancement of Cyber-Physical Systems has attracted attention to Mixed-Criticality Systems (MCSs), both in research and in industrial designs. As multicore platforms are becoming the dominant trend in MCSs, joint energy and reliability management is a crucial issue. In addition, providing guaranteed service level for low-criticality tasks in critical mode is of great importance. To address these problems, we propose LETR-MC scheme that simultaneously supports certification, energy management, fault-tolerance, and guaranteed service level in mixed-criticality multicore systems. In this paper, we exploit task-replication to not only satisfy reliability requirements, but also to improve the QoS...
Measuring data quality of theses and dissertations in the data preparation stage of registration systems
, Article International Journal of Information Science and Management ; Volume 21, Issue 4 , 2023 , Pages 189-213 ; 20088302 (ISSN) ; Mohseni, A ; Akhavan Niaki, T ; Sharif University of Technology
Regional Inform. Center for Sci. and Technol
2023
Abstract
Today, academic research plays a very influential role in the economic development of countries. These researches are often recorded and disseminated in the form and structure of theses and dissertations in scientific institutes. The better the quality of this data in the systems that collect and distribute it, the more it can be used and exploited by organizations and businesses. Therefore, providing this data requires proper monitoring to put the output of the recording and dissemination process in good condition. This paper offers a framework for evaluating theses and dissertation data quality. In the framework, the data inconsistency coding structure is introduced and presented in Word...
Economic-statistical design of simple linear profiles with variable sampling interval
, Article Journal of Applied Statistics ; Volume 43, Issue 8 , 2016 , Pages 1400-1418 ; 02664763 (ISSN) ; Noorossana, R ; Akhavan Niaki, S. T ; Sharif University of Technology
Taylor and Francis Ltd
2016
Abstract
Control charts are statistical tools to monitor a process or a product. However, some processes cannot be controlled by monitoring a characteristic; instead, they need to be monitored using profiles. Economic-statistical design of profile monitoring means determining the parameters of a profile monitoring scheme such that total costs are minimized while statistical measures maintain proper values. While varying sampling interval usually increases the effectiveness of profile monitoring, economic-statistical design of variable sampling interval (VSI) profile monitoring is investigated in this paper. An extended Lorenzen–Vance function is used for modeling total costs in VSI model where the...
Economic design of phase 2 simple linear profiles with variable sample size
, Article International Journal of Productivity and Quality Management ; Volume 18, Issue 4 , 2016 , Pages 518-536 ; 17466474 (ISSN) ; Noorossana, R ; Akhavan Niaki, S. T ; Sharif University of Technology
Inderscience Enterprises Ltd
2016
Abstract
Employing profiles using variable sample size (VSS) may improve its effectiveness and hence is investigated in this paper. Besides, the implementation cost of a profile is an important factor in determining the main parameters. In this paper, the Lorenzen-Vance function is first extended to model implementation cost of VSS linear profiles. Then, the resulted economic model is solved using a genetic algorithm (GA). The average run length criterion when process is in control, ARL0 and the average run length measure when process goes out of control, ARL1 , is used to evaluate statistical properties of the designed profile. Moreover, a sensitivity analysis on the main parameters of the...
Desgin and Implementation of Integrated Class EM Power Amplifier at 2.4 GHz
, M.Sc. Thesis Sharif University of Technology ; Medi, Ali (Supervisor)
Abstract
This project proposes a novel design technique for implementation of class-EM power amplifier (PA). Class-EM mode of operation has been proposed as the improved version of class-E; outclasses in terms of efficiency as well as power gain. Specifically, provided that the current fall time of switch is an appreciable portion of a period; frequency of operation is high enough that the switching time of transistor can no longer be considered instantaneous in other words. A novel technique for harmonic injection required for class-EM operation is proposed. Followed by the system of equations and the design methodology governing the proposed circuit. As a proof of concept and verification of the...
Investigation of integrated smooth transistor's switching transition power amplifier-2.4-GHz realization of class-EM
, Article IEEE Transactions on Microwave Theory and Techniques ; Volume 65, Issue 8 , 2017 , Pages 3046-3055 ; 00189480 (ISSN) ; Medi, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
This paper proposes a design technique for the implementation of a class-EM power amplifier (PA). Class- EM mode of operation has been proposed as an improved version of class-E in terms of efficiency and power gain, provided that the current fall time of switch is an appreciable portion of a period; the frequency of operation is high enough that the switching time of transistor can no longer be considered instantaneous. A novel approach for harmonic injection required for class-EM operation is proposed, followed by the system of equations and the design methodology governing the proposed circuit. As a proof of concept and verification of the proposed design method, a class-EM PA is designed...
An economic-statistical design of simple linear profiles with multiple assignable causes using a combination of MOPSO and RSM
, Article Soft Computing ; Volume 25, Issue 16 , 2021 , Pages 11087-11100 ; 14327643 (ISSN) ; Ershadi, M. M ; Haghighi Naeini, S ; Akhavan Niaki, S. T ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
An economic-statistical design with multiple assignable causes following exponential distribution is presented in this paper for linear profiles. For this purpose, a tri-objective optimization model is proposed to minimize the cost with desired statistical performances. Average Run Length (ARL) as the primary statistical measure is employed for the appraisal of the designed linear profiles. The first objective to be minimized is a cost function that models the implementation cost in different states. The second objective is to maximize ARL or the in-control average run-length of the monitoring scheme. The third objective to be minimized is ARL 1 or the out-of-control average run-length of...
A hierarchical machine learning model based on Glioblastoma patients' clinical, biomedical, and image data to analyze their treatment plans
, Article Computers in Biology and Medicine ; Volume 150 , 2022 ; 00104825 (ISSN) ; Rahimi Rise, Z ; Akhavan Niaki, S. T ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Aim of study: Glioblastoma Multiforme (GBM) is an aggressive brain cancer in adults that kills most patients in the first year due to ineffective treatment. Different clinical, biomedical, and image data features are needed to analyze GBM, increasing complexities. Besides, they lead to weak performances for machine learning models due to ignoring physicians' knowledge. Therefore, this paper proposes a hierarchical model based on Fuzzy C-mean (FCM) clustering, Wrapper feature selection, and twelve classifiers to analyze treatment plans. Methodology/Approach: The proposed method finds the effectiveness of previous and current treatment plans, hierarchically determining the best decision for...
AM3D: An accurate crosstalk probability modeling to predict channel delay in 3D ICs
, Article Microelectronics Reliability ; Volume 102 , 2019 ; 00262714 (ISSN) ; Nikoofard, A ; Ershadi, G ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Migration from Two Dimensional Integrated Circuits (2D ICs) to Three Dimensional Integrated Circuits (3D ICs) reduces the delay due to the shorter wire length between sender and receiver. However, Through-Silicon-Vias (TSVs) that connect layers in the structure of 3D ICs can seriously increase the delay due to capacitance coupling between TSVs and lead to crosstalk fault. The severity of crosstalk faults depends on transitions appearing on TSVs that is called transition patterns. To propose an efficient crosstalk tackling mechanisms in 3D ICs, an accurate probability analytical model is required to predict the delay caused by TSVs (3D ICs) in the attendance of these transition patterns. In...
LESS-MICS: A low energy standby-sparing scheme for mixed-criticality systems
, Article IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems ; Volume 39, Issue 12 , 2020 , Pages 4601-4610 ; Hessabi, S ; Ershadi, G ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Multicore platforms are becoming the dominant trend in mixed-criticality systems (MCSs). Multicores provide great opportunities to realize task-level redundancy for reliability enhancement. However, they may experience limited utility in battery-powered mixed-criticality embedded systems. Hence, joint energy and reliability management is a crucial issue in designing MCSs. In this article, we propose the low energy standby-sparing mechanism in mixed-criticality system (LESS-MICS) scheme, which uses the inherent redundancy of multicores to apply the standby-sparing technique for fault-tolerance. Also, by using the inherent redundancy, the LESS-MICS scheme proposes the Parallelism and Reduction...
Regression-based convolutional 3D pose estimation from single image
, Article Electronics Letters ; Volume 54, Issue 5 , March , 2018 , Pages 292-293 ; 00135194 (ISSN) ; Kasaei, S ; Sanaei, E ; Sharif University of Technology
Institution of Engineering and Technology
2018
Abstract
Estimation of 3D human pose from a single image is a challenging task because of ambiguities in projection from 3D space to the 2D image plane. A new two-stage deep convolutional neural network-based method is proposed for regressing the distance and angular difference matrices among body joints. Using the angular difference between body joints in addition to the distance between them in articulated objects such as human body can better model the structure of the shapes and increases the modelling capability of the learning method. Experimental results on HumanEva I and Human3.6M datasets show that the proposed method has substantial improvement in the mean per joint position error measure...
Uncalibrated multi-view multiple humans association and 3D pose estimation by adversarial learning
, Article Multimedia Tools and Applications ; 2020 ; Kasaei, S ; Sanaei, E ; Sharif University of Technology
Springer
2020
Abstract
Multiple human 3D pose estimation is a useful but challenging task in computer vison applications. The ambiguities in estimation of 2D and 3D poses of multiple persons can be verified by using multi-view frames, in which the occluded or self-occluded body parts of some persons might be visible in other camera views. But, when cameras are moving and uncalibrated, estimating the association of multiple human body parts among different camera views is a challenging task. This paper presents novel methods for multiple human 3D pose estimation and pose association in multi-view camera frames in an uncalibrated camera setup using an adversarial learning framework. The generator is a 3D pose...
Uncalibrated multi-view multiple humans association and 3D pose estimation by adversarial learning
, Article Multimedia Tools and Applications ; Volume 80, Issue 2 , 2021 , Pages 2461-2488 ; 13807501 (ISSN) ; Kasaei, S ; Sanaei, E ; Sharif University of Technology
Springer
2021
Abstract
Multiple human 3D pose estimation is a useful but challenging task in computer vison applications. The ambiguities in estimation of 2D and 3D poses of multiple persons can be verified by using multi-view frames, in which the occluded or self-occluded body parts of some persons might be visible in other camera views. But, when cameras are moving and uncalibrated, estimating the association of multiple human body parts among different camera views is a challenging task. This paper presents novel methods for multiple human 3D pose estimation and pose association in multi-view camera frames in an uncalibrated camera setup using an adversarial learning framework. The generator is a 3D pose...
Monitoring data quality using hoteling multivariate control chart
, Article Communications in Statistics: Simulation and Computation ; Volume 52, Issue 4 , 2023 , Pages 1591-1606 ; 03610918 (ISSN) ; Akhavan Niaki, T ; Azizi, A ; Ashtian Esfahani, A ; Edris Abadi, R ; Sharif University of Technology
Taylor and Francis Ltd
2023
Abstract
Nowadays, data and information are recognized as a precious resource in an organization. Data quality indicators help organizations manage the quality of data quantitatively and improve organizational processes. Organizations manage data and information with the help of information systems and make decisions within the framework of data collected and analyzed. On the other hand, continuous evaluation of the quality of data flow in systems can lead to a preventive program to formulate strategies for improving performance. This can be done effectively and efficiently in the form of control charts. In this paper, control charts are employed to monitor the quality of data flow in information...
Economic-Statistical Design and Evaluation of Multivariate Control Charts; An Improvement of Cost Model and Constraints Approach
, M.Sc. Thesis Sharif University of Technology ; Akhavan Niaki, Taghi (Supervisor)
Abstract
Control charts are the best tools for determining the deviations in the main parameters of a process. Exponentially weighted moving average, EWMA, control charts are the best type for determining small deviations. Determining the control charts parameters by means of minimizing a cost model is economic design. Economic-statistical design is achieved by adding statistical constraints to the economic model. Average run length when the process is in control, ARL0, and average run length when the process is out of control, ARL1, are limited in the economic-statistical model. In this thesis the economic-statistical design of a multivariate EWMA control chart is considered and this model is solved...