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What happened to complex product systems literature over the last two decades: progresses so far and path ahead
, Article Technology Analysis and Strategic Management ; Volume 30, Issue 8 , 2018 , Pages 948-966 ; 09537325 (ISSN) ; Park, T. Y ; Kiamehr, M ; Sharif University of Technology
Routledge
2018
Abstract
Complex product systems (CoPS) industries largely contribute to industrial development, economic growth and creation of national wealth in both developed and developing economies. CoPS also show a number of specific characteristics as a distinctive category of industrial products in comparison with mass-produced consumer goods. These aspects have attracted the attention of scholars to study CoPS over the last two decades, resulting in a fairly extensive body of literature on the subject. However, there is a further need to connect research findings in this area, to illustrate a macro view of the development in the field, explore common themes, and identify possible paths into the future....
Innovation policy, scientific research and economic performance: The case of Iran
, Article Development Policy Review ; Volume 38, Issue 3 , 2020 , Pages 387-407 ; Babaee, A ; Maleki, A ; Isaai, M. T ; Sharif University of Technology
Blackwell Publishing Ltd
2020
Abstract
Motivation: Why, despite substantial investment in science and technology infrastructure during the last two decades, has Iran performed relatively poorly in terms of innovation and economic output? The investment has been wide-ranging, from the inclusion of science and technology in the National Development Plans to the impressive growth in the number of science and technology parks and incubators. Iran is among the top five countries in terms of science and engineering graduates, and Iran's scientific publications are among the world's fastest-growing. Purpose: This study attempts to discover the reasons for this poor performance despite the investment. Approach and Method: This is a...
Designing an efficient blood supply chain network in crisis: neural learning, optimization and case study
, Article Annals of Operations Research ; Volume 289, Issue 1 , 30 October , 2020 , Pages 123-152 ; Soltanzadeh, S ; Weber, G. W ; Roy, S. K ; Sharif University of Technology
Springer
2020
Abstract
In recent years, attention to blood supply chain in disaster circumstances has significantly increased. Disasters, especially earthquakes, have adverse consequences such as destruction, loss of human lives, and undermining the effectiveness of health services. This research considers a six-echelon blood supply chain which consists of donors, blood collection centers (permanent and temporary), regional blood centers, local blood centers, regional hospitals, and local hospitals. For the first time, we considered that helicopters could carry blood from regional hospitals to local hospitals and return injured people that cannot be treated in local hospitals to regional hospitals due to the...
National laser research progress in context of international developments
, Article Journal of Applied Sciences ; Volume 8, Issue 17 , 2008 , Pages 2958-2966 ; 18125654 (ISSN) ; Sharif University of Technology
2008
Abstract
This study presents an up to date progress of the national and international laser research and developments. The number of scientific publications and accepted patents are considered as a figure of merit and based on these numbers the growth pace for the period of 1990-2003 is investigated. The share of top nations in scientific publications and in particular laser publications in term of their Gross Domestic Product (GDP) is presented. Four countries including the USA, Japan, Germany and China have a laser publication contribution of 58.9% while the rest of the world including (189) countries contribute 41.1%. However, for the case of accepted patents, which are the more important factor,...
Thermodynamic and environmental consideration of advanced gas turbine cycles with reheat and recuperator
, Article International Journal of Environmental Science and Technology ; Volume 4, Issue 2 , 2007 , Pages 253-262 ; 17351472 (ISSN) ; Ghofrani, M. B ; Sharif University of Technology
CEERS
2007
Abstract
The role of gas turbine power plants in electrical energy production has been considerably increased in the last two to three decades. Various methods have been proposed to improve the performance of gas turbine cycles. In this research, two methods, a reheat cycle and a cycle with a reheat and a recuperator, were investigated and compared with a simple cycle. The main objective of this paper is to study the performance of an simple cycle and reheat cycle under actual conditions. In this regard, all processes are treated as actual, and in particular a relatively simple and reliable approach is used to predict the amount of cooling air. The results obtained on the basis of a model developed...
DMLS gets an expert once-over
, Article Metal Powder Report ; Volume 61, Issue 4 , 2006 , Pages 10-13 ; 00260657 (ISSN) ; Pohl, H ; Simchi, A ; Alcantara, B ; Sharif University of Technology
Elsevier Ltd
2006
Abstract
Direct Metal Laser Sintering has real potential for rapid-manufacture applications in the PM arena, reducing lead times and cutting costs. But it has been hampered by the limited range of suitable powders available and their cost. A research group led by Fraunhofer scientists made their own powders and took a closer look.... © 2006 Elsevier Ltd. All rights reserved
Fair allocation of indivisible goods: Improvement
, Article Mathematics of Operations Research ; Volume 46, Issue 3 , 2021 , Pages 1038-1053 ; 0364765X (ISSN) ; Hajiaghayi, M. T ; Seddighin, M ; Seddighin, S ; Yami, H ; Sharif University of Technology
INFORMS Inst.for Operations Res.and the Management Sciences
2021
Abstract
We study the problem of fair allocation for indivisible goods. We use the maximin share paradigm introduced by Budish [Budish E (2011) The combinatorial assignment problem: Approximate competitive equilibrium from equal incomes. J. Political Econom. 119(6):1061-1103.] as a measure of fairness. Kurokawa et al. [Kurokawa D, Procaccia AD, Wang J (2018) Fair enough: Guaranteeing approximate maximin shares. J. ACM 65(2):8.] were the first to investigate this fundamental problem in the additive setting. They showed that in delicately constructed examples, not everyone can obtain a utility of at least her maximin value. They mitigated this impossibility result with a beautiful observation: no...
A theoretical and experimental investigation on wire flat rolling process using deformation pattern
, Article Materials and Design ; Volume 26, Issue 2 , 2005 , Pages 99-103 ; 02613069 (ISSN) ; Karimi Taheri, A ; Sharif University of Technology
Elsevier Ltd
2005
Abstract
In this research the deformation of wire in flat rolling process has been investigated. A theoretical relationship has been developed to relate the reduction in height of wire to the width of contact area between the rolls and wire. This relationship depicts that the width of contact area is proportional to square root of reduction in height of wire. Using that relationship the width of contact area for wires of different diameter have been calculated and compared with the appropriate experimental data after flat rolling. Also, a relationship is developed to assess the effect of reduction in height of wire on the lateral spread in wire flat rolling process. Moreover, the effect of material...
Reliability function of a class of time-dependent systems with standby redundancy
, Article European Journal of Operational Research ; Volume 164, Issue 2 , 2005 , Pages 378-386 ; 03772217 (ISSN) ; Katagiri, H ; Sakawa, M ; Modarres, M ; Sharif University of Technology
2005
Abstract
By applying shortest path analysis in stochastic networks, we introduce a new approach to obtain the reliability function of time-dependent systems with standby redundancy. We assume that not all elements of the system are set to function from the beginning. Upon the failure of each element of the active path in the reliability graph, the system switches to the next path. Then, the corresponding elements are activated and consequently the connection between the input and the output is established. It is also assumed each element exhibits a constant hazard rate and its lifetime is a random variable with exponential distribution. To evaluate the system reliability, we construct a directed...
A mixed methods approach to exploring grammar learning strategies in self-regulation task phases: Evidence from grounded theory and regression analysis
, Article Language Teaching Research ; 2022 ; 13621688 (ISSN) ; Ranjbar, M ; Sharif University of Technology
SAGE Publications Ltd
2022
Abstract
While research into various dimensions of language learning strategies has been thriving over the recent years, grammar learning strategies (GLS) have largely remained under-explored. The present mixed methods research aimed to explore GLS in the three stages of classroom grammar tasks, while striving to determine the sequence of GLS and their contribution to grammar proficiency. In the qualitative phase, 13 participants partook in stimulated recall and semi-structured interviews after completing consciousness-raising (CR) tasks. Then, the grounded theory (GT) methodology was applied to conceptualize a theoretical model. For the quantitative phase, a modified version of Pawlak’s Grammar...
A practical approach to R&D portfolio selection using the fuzzy pay-off method
, Article IEEE Transactions on Fuzzy Systems ; Volume 20, Issue 4 , 2012 , Pages 615-622 ; 10636706 (ISSN) ; Collan, M ; Modarres, M ; Sharif University of Technology
IEEE
2012
Abstract
The objective of this research is to develop a practical research and development (R&D) portfolio selection model that addresses the effective R&D project valuation issue, while tackling R&D uncertainty in portfolio optimization. Fuzzy set theory is employed to capture and model the uncertain project information. To evade the well-known complexities of fuzzy real option valuation, the recently developed fuzzy pay-off method is used to more effectively valuate R&D projects. The resulting problem is formulated as a fuzzy zero-one integer programming model that handles uncertainty of input data in order to determine the optimal portfolio. Two satisfaction measures, which are based on...
Uncertainty evaluation of calculated and measured kinetics parameters of Tehran Research Reactor
, Article Nuclear Engineering and Design ; Volume 240, Issue 10 , 2010 , Pages 2761-2767 ; 00295493 (ISSN) ; Vosoughi, N ; Sharif University of Technology
Abstract
Effective delayed neutron fraction βeff and neutron generation time Λ are important factors in reactor physics calculation and transient analysis. In the first stage of this research, these kinetics parameters have been calculated for two states of Tehran Research Reactor (TRR), i.e. cold (fuel, clad and coolant temperature 20 °C) and hot (fuel, clad and coolant temperature 65, 49 and 44 °C, respectively) states using MTR-PC computer code. The ratio of (βeff) i/(βeff)core plays an important role in reactivity accident analysis codes. This parameter and its contribution to effective delayed neutron fraction from each nucleus have been calculated in cold and hot reactor states. Uncertainty of...
Calculation, measurement and sensitivity analysis of kinetic parameters of tehran research reactor
, Article Annals of Nuclear Energy ; Volume 37, Issue 4 , April , 2010 , Pages 463-470 ; 03064549 (ISSN) ; Vosoughi, N ; Ghofrani, M. B ; Gharib, M ; Sharif University of Technology
2010
Abstract
Effective delayed neutron fraction βeff and neutron generation time Λ are important factors in reactor physics calculation and transient analysis. In the first stage of this research, these kinetic parameters have been calculated for two states of Tehran Research Reactor (TRR), i.e. cold (fuel, clad and coolant temperatures equal to 20 °C) and hot (fuel, clad and coolant temperatures of 65, 49 and 44 °C, respectively) states using MTR_PC code. In the second stage, these parameters have been measured with an experimental method based on Inhour equation. For the cold state, calculated βeff and Λ by MTR_PC code are 0.008315 and 30.190 μs, respectively. In the hot state, these parameters being...
Sensitivity analysis of kinetics parameters of Tehran Research Reactor (TRR)
, Article 17th International Conference on Nuclear Engineering, 12 July 2009 through 16 July 2009 ; Volume 5 , 2009 , Pages 419-423 ; 9780791843550 (ISBN) ; Vosoughi, N ; Nuclear Engineering Division, ASME; The Japan Society of Mechanical Engineers, JSME; The Chinese Nuclear Society, CNS ; Sharif University of Technology
Abstract
In this research, effective delayed neutron fraction (βeff) and neutron generation time (A) of the Tehran Research Reactor (TRR) are calculated for different uranium enrichments from 14.84 w/o to 96.56 w/o U 235 in two states of the TRR, (cold fuel, clad and coolant temperature of 20°C; and hot fuel, clad and coolant temperature of 65, 49 and 44°C, respectively) using the MTR-PC computer code. Comparative analysis shows that both βeff and Λ increase as fuel enrichment decreases. However, variation rate βeff is not the same in two conditions. βeff in the hot state is larger than those calculated in the cold state when fuel enrichment goes more than 83.91%, while the situation is reverse for...
Review of data science trends and issues in porous media research with a focus on image-based techniques
, Article Water Resources Research ; Volume 57, Issue 10 , 2021 ; 00431397 (ISSN) ; Fernando, A. M ; Shams, R ; Singh, A ; Mostaghimi, P ; Babaei, M ; Sharif University of Technology
John Wiley and Sons Inc
2021
Abstract
Data science as a flourishing interdisciplinary domain of computer and mathematical sciences is playing an important role in guiding the porous material research streams. In the present narrative review, we have examined recent trends and issues in data-driven methods used in the image-based porous material research studies relevant to water resources researchers and scientists. Initially, the recent trends in porous material data-related issues have been investigated through search engine queries in terms of data source, data storage hub, programing languages, and software packages. Subsequent to a diligent analysis of the existing trends, a review of the common concepts of porous material...
Providing a Project Management Methodology for Research Projects
,
M.Sc. Thesis
Sharif University of Technology
;
Shadrokh, Shahram
(Supervisor)
Abstract
In this thesis a project management methodology for research projects is presented. Generally, implementing research projects is so complicated because of uncertain attributes of this type of projects. So far, no project management methodology has been developed for research projects. In this thesis first, the main attributes of research projects are identified by considering research projects problems in some organizations. The consideration involves studying documents of research projects, interviewing with project managers, using questionnaires and applying statistical analyses. Then, stakeholders’ expectations of a research project methodology are recognized and characteristics of the...
Modeling and Design of CCHP System for Sharif Energy Research Institute
, M.Sc. Thesis Sharif University of Technology ; Sabbohi, Yadollah (Supervisor)
Abstract
The aim of the present research project has been techno-economical analysis of using a CCHP (Combined Cooling Heating and Power) technology at the building of Sharif Energy Research Institute (SERI). The CCHP at SERI is supposed to supply energy required at the building. Useful energy demand at the building include heating in winter, cooling and air conditioning in summer, lighting and power requirement of electric appliance and equipments. Since there are many technologies that could be utilized as CCHP, an optimal model of energy supply system of the building has been developed in order to identify the most appropriate technology. The application of model has enabled techno logical...
Model for Planning Flow of Knowledge to Optimize Energy and the Environment
, M.Sc. Thesis Sharif University of Technology ; Saboohi, Yadollah (Supervisor)
Abstract
The purpose of this study is to investigate and analyse the technological transition of a new clean energy technology in the market. The agent-based modeling is used in national innovation chain to describe knowledge spillover between main actors in innovation procedure in order to attain renewable energy technology (RET) from basic research to commercial stage. Government’s expenditure on training human resource and R&D activities is modeled as a tool to analyse the development of innovation chain in order to increase diffusion rate of the new technology. Application of the knowledge flow model is demonstrated through analysis of introduction of solar PV in the energy system of Iran and...
Predicting Research Trends by Using Link Prediction in Keywords Network
, M.Sc. Thesis Sharif University of Technology ; Hajsadeghi, Khosrow (Supervisor) ; Kavousi, Kaveh (Co-Advisor)
Abstract
The rapid development of scientific areas in this modern era makes the process of finding new field of research slow and laborious for prospective scholars. Thus, having a vision of the future could be helpful to pick a right path for doing researches and ensuring that it is worth to invest in. This thesis seeks to predict research trends by using link prediction approaches on keywords network and discusses about the performance of various algorithms in different situations. Moreover, for the last part of the experiments, novel link prediction algorithms are proposed by the author, enhances the accuracy of prediction results. The data set collected from Sciencedirect and Scopus by a strong...
Review of Contemporary Islamology Streams as Rational Traditions, Considering Macintyre View Points
, M.Sc. Thesis Sharif University of Technology ; Golshani, Mahdi (Supervisor)
Abstract
Shia theology has gone through different transformations throughout history. In the contemprorary age diverse studies have been carried out in order to discribe it’s preceding changes and future transformations. This tesis tends to show at first that “MacIntyre’s method of historical-philosophical study” is an overally justified model for such studeis, in comparison with the two other models of “Kuhn’s model of scientific revolutions” & “Lakatos’s research programs.” Afterwards, this model has been used for the study of shia theology and a brief narration of the rationality traditions of shia theology through the Iranian tradition has been given. The focus of this section has been on the...