An integrated vendor-buyer inventory model with partial backordering

, Article Journal of Manufacturing Technology Management ; Volume 23, Issue 7 , 2012 , Pages 869-884 ; 1741038X (ISSN) Moshrefi, F ; Jokar, M. R. A ; Sharif University of Technology

2012

Abstract

Purpose - The purpose of this paper is to analyze the effects of supply chain coordination on inventory management while the retailer inventory cycle consists of a shortage period and the backorder rate linearly decreases as a function of shortage duration. It is intended to consider how on-hand inventory and shortage durations are altered when the decisions are centralized. Design/methodology/approach - Mathematical modelling of inventory costs for the retailer and the vendor is used to formulate objective functions. The vendor sets his inventory period as an integer multiple (n) of the retailer inventory cycle in which the integer multiple is a decision variable. Solution spaces of models...

Evaluating Vendor Managed Inventory Policy considering Partial Variable Backorder

, M.Sc. Thesis Sharif University of Technology Moshrefi, Fateh (Author) ; Akbari Jokar, Mohammad Reza (Supervisor)

Abstract

Inventory problems are studied for a long time and many authors have investigated models with shortage phenomenon. To reduce inventory holding cost or decaying items we can have a shortage period in witch a part of demand is backordered; Although we pay fines to pending costumers, as shortage period is extended a larger portion of them will refuse to wait until replenishment. So, calculating an optimal duration for on hand inventory and shortage period with respect to inventory costs has became an interesting research field. However, related studies are rarely appeared in supply chain researches, where an integrated inventory model for a supplier and a retailer is proposed; especially when a...

A macro analytic success model for Entrepreneurial university

, Article World Applied Sciences Journal ; Volume 27, Issue 8 , 2013 , Pages 1049-1056 ; 18184952 (ISSN) Fateh rad, M ; Mansourian, F ; Lotfi, H ; Sharif University of Technology

2013

Abstract

One of the new forming world discipline feature is knowledge based innovation. World new discipline, vitality condition is to establish new science and technology and suitable utility from that. Therefore, the new era witness those grand variations in university systems and for more utilization process in national, regional and international economical development. In this context, traditional university variation and conversion to Entrepreneurial University and holding and creating idea and supporting it to transform in final product or service is concerned, which means knowledge-based entrepreneurship. Thus, this university can develop knowledge-based staff and has nontraditional processes...

Investment cost optimization for industrial project portfolios using technology mining

, Article Technological Forecasting and Social Change ; Volume 138 , 2019 , Pages 243-253 ; 00401625 (ISSN) Azimi, S ; Rahmani, R ; Fateh rad, M ; Sharif University of Technology

Elsevier Inc 2019

Abstract

Large technology-intensive enterprises and companies face a constant challenge: How can a set of selected high-tech projects get done in a manner that would minimize the total cost across all projects? In majority of cases, projects are assumed independent, leading to a separate cost evaluation. This assumption often does not hold for real-world project portfolios, frequently sharing overlapping technologies. In this paper, we show how the order of the execution of the projects can directly affect the total cost of the portfolio, due to shared dependencies. Modeling the problems in this area can be achieved by combining two main fields: graph theory and technology mining. A novel method is...

Effects of Price Ceiling on Uniform Price Electricity Auction Markets

, M.Sc. Thesis Sharif University of Technology Moshrefi, Hamid Reza (Author) ; Ebrahimnejad, Ali (Supervisor) ; Mohaghegh, Mohsen (Supervisor)

Abstract

One of the most common applications of multi-unit auctions is the energy markets, including the electricity markets. In this study, using the simulation of a uniform price wholesale electricity market, the effects of the price ceiling on the behavior of power plants and market clearing prices have been investigated. The results show that the implication of price ceilings causes power plants to reduce the slope of their bidding function near the ceiling price, and as a result, the market-clearing price decreases compared to the previous state in the absence of the price ceiling. It was also observed that the higher the probability of reaching the price ceiling (higher total demand), the more...

Subject-specific and function-specific applicability of a hand-forearm musculoskeletal model

, Article Biomedical Engineering - Applications, Basis and Communications ; Volume 27, Issue 6 , 2015 ; 10162372 (ISSN) Hosseininejad, S ; Farahmand, F ; Fateh, H. R ; Forogh, B ; Sharif University of Technology

World Scientific Publishing Co. Pte Ltd 2015

Abstract

There is ambiguity on the quantitative validity of the predictions revealed by musculoskeletal models for muscle forces. This study investigated the consistency between the predictions of a musculoskeletal model of the upper limb and the experimental data for a number of different subjects and functional tasks. Six normal subjects performed isokinetic eccentric or isotonic concentric contraction tests of the wrist muscles in well controlled conditions, using a robotic apparatus, and the net joint torque and angular velocities, as well as the surface electromyograms (EMG) signals of the muscles, were recorded. The experiments were then simulated using a parametric musculoskeletal model of...

An effective collaboration model between industry and university based on the theory of self organization: A system dynamics model

, Article Journal of Science and Technology Policy Management ; Volume 6, Issue 1 , 2015 , Pages 2-24 ; 20534620 (ISSN) Fateh Rad, M ; Seyedesfahani, M. M ; Jalilvand, M. R ; Sharif University of Technology

Emerald Group Publishing Ltd 2015

Abstract

Purpose - This study aims to investigate the relationship between university and industry as two major infrastructures of national innovation system in all leading scientific and industrial settings. Design/methodology/approach - Large complex organizations with high technology that follow non-linear dynamic rules need to define concepts and adopt new approaches to achieve organizational efficiency and effectiveness. Among various models, a dynamic model of innovation was developed based on a joint investment between industry and university. Hence, the concepts of systems thinking and system dynamics were used.Findings- The results reveal three levels of industry and university communication...

Discovering associations among technologies using neural networks for tech-mining

, Article IEEE Transactions on Engineering Management ; 2020 Azimi, S ; Veisi, H ; Fateh rad, M ; Rahmani, R ; Sharif University of Technology

Institute of Electrical and Electronics Engineers Inc 2020

Abstract

In both public and private sectors, critical technology-based tasks, such as innovation, forecasting, and road-mapping, are faced with unmanageable complexity due to the ever-expanding web of technologies which can range into thousands. This context cannot be easily handled manually or with efficient speed. However, more precise and insightful answers are expected. These answers are the fundamental challenge addressed by tech-mining. For tech-mining, discovering the associations among them is a critical task. These associations are used to form a weighted directed graph of technologies called “association tech-graph” which is used for technology development, trend analysis, policymaking,...

Discovering associations among technologies using neural networks for tech-mining

, Article IEEE Transactions on Engineering Management ; Volume 69, Issue 4 , 2022 , Pages 1394-1404 ; 00189391 (ISSN) Azimi, S ; Veisi, H ; Fateh-Rad, M ; Rahmani, R ; Sharif University of Technology

Institute of Electrical and Electronics Engineers Inc 2022

Abstract

In both public and private sectors, critical technology-based tasks, such as innovation, forecasting, and road-mapping, are faced with unmanageable complexity due to the ever-expanding web of technologies which can range into thousands. This context cannot be easily handled manually or with efficient speed. However, more precise and insightful answers are expected. These answers are the fundamental challenge addressed by tech-mining. For tech-mining, discovering the associations among them is a critical task. These associations are used to form a weighted directed graph of technologies called 'association tech-graph' which is used for technology development, trend analysis, policymaking,...

Comparison of strengths of five internal fixation methods used after bilateral sagittal split ramus osteotomy: An in vitro study

, Article Dental Research Journal ; Volume 17, Issue 4 , 2020 , Pages 258-265 Sarkarat, F ; Ahmady, A ; Farahmand, F ; Fateh, A ; Kahali, R ; Nourani, A ; Rakhshan, V ; Sharif University of Technology

Wolters Kluwer Medknow Publications 2020

Abstract

Results on the strength and displacement of internal fixation methods for bilateral sagittal split ramus osteotomy are controversial, and some designs have not been adequately studied. Therefore, this study was conducted to compare techniques using bicortical or monocortical screws. Materials and Methods: In this in vitro study, 35 sheep hemi-mandibles were randomly assigned to five groups of seven each: fixation using (1) a 13 × 2 screw, (2) two 13 × 2 screws (arranged vertically), (3) three 13 × 2 screws, (4) 1 plate with 4 holes and four monocortical screws, and (5) a Y-shaped plate and five monocortical screws. Specimens underwent vertical forces until failure. Breakage forces and...