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991.
Seyed Ahmad Yazdian Kamran Shahanaghi Ahmad Makui 《International journal of systems science》2016,47(5):1155-1175
We investigate joint optimisation of remanufacturing, pricing and warranty decision-making for end-of-life products. A novel mathematical–statistical model is proposed where decisions involve pricing of returned used products (cores), degree of their remanufacturing, selling price and the warranty period for the final remanufactured products. The virtual age reliability improvement approach is chosen to model the upgrading of the cores to higher quality levels. We consider price- and warranty-dependent demand, price- and age-dependent return, and age-dependent remanufacturing cost in the model development. Both linear and non-linear forms of these functions are investigated. First, under some restrictive conditions of upgrade level and age distribution of received cores, special cases of the problem, which can be solved using a recently developed non-linear optimisation solver, are presented. We also implement a particle swarm optimisation algorithm for the solution of the original problem when all the restrictive assumptions are dropped. Finally, numerical experiments and sensitivity analysis are presented to address different aspects of the model and the solution approaches. 相似文献
992.
Mehdi Dadkhah Tomasz Maliszewski Vyacheslav V. Lyashenko 《Behaviour & Information Technology》2016,35(4):298-303
Hijacked journals are cloned websites that resemble the homepages of legitimate journals, whose aim is to collect processing and publication fees from unwary authors. There is a growing recognition that the recent proliferation of these scam sites poses a threat to the integrity of the scientific process. This study presents an approach intended to prevent the indexing of papers published by hijacked journals in scientific databases by using classification algorithms. We will provide an overview of the problem, define key features of hijacked journals, and present a decision tree that can be used to detect hijacked publications. 相似文献
993.
Mehdi Fasanghari Fouad Bahrpeyma Fariborz Jolai 《Neural computing & applications》2016,27(7):1981-1992
While active learning method (ALM) uses error as the learning parameter, selection of the validation data is still challenging. In this paper, to prevent form encountering with sample size problem, we applied an error-independent version of ALM that we call the active fuzzy modeling (AFM) with a distance threshold to model parameters of hydrocarbon reservoirs. In this paper, we demonstrate that measuring the generalization error is a vital factor in the process of ALM. Regression (R) and mean squared error (MSE) for estimating RHOB by AFM were 0.96 and 0.0032, respectively. On the other hand, R of 0.91, 0.89 and 0.92 and MSE of 0.0051, 0.0067 and 0.0047 for ANN, TS-FIS and NF, respectively, illustrate that AFM performs much better in comparison with conventional modeling approaches and produces more reliable results. Comparing the results of the presented method with ANN, TS-FIS and NF in aspect of rapidity, robustness, storage, complexity and acceptability in estimating RHOB reports the accuracy and high-performance behavior of AFM. This method is illustrated by an example of an oil field at NW Persian Gulf. 相似文献
994.
Seyed Mohammad Karim Tabatabaei Saeed Behbahani Pouya Rajaeipour 《Microsystem Technologies》2016,22(10):2435-2446
Energy harvesting is about deriving energy from environment and converting into electricity. In this paper, optimal design of a cantilever piezoelectric energy harvester is presented with the aim to capture electrical power from a vibratory feeder in mining industry. Rayleigh–Ritz method is utilized for the modeling of the cantilever piezoelectric, taking into account possible variation in the width, nonequivalent layer lengths and thickness for unimorph and bimorph configurations. Innovatively, intelligent artificial immune system is utilized for multi-objective optimization of the shape parameters of the system. To verify the presented analytical shape optimization method, finite element analysis of the designed system is also presented, to investigate the output voltage and stress distribution along the piezoelectric layer. Moreover, the experimental setup is generated and verification tests are performed to derive frequency response diagram of the system. The obtained results are encouraging, indicating good agreement between experiments, FE analysis and theoretical results. 相似文献
995.
Seyed Mostafa Banihashemi Tehrani Ali Moosavi Hani Sadrhosseini 《Microsystem Technologies》2016,22(5):965-977
The World Health Organization (WHO) in 2013 reported that more than seven million unexpected losses every year are credited to air contamination. Because of incredible adaptability and expense viability of fibrous filters, they are broadly used for removing particulates from gasses. The influence of appropriate parameters, e.g., the fiber arrangement, solid volume fraction (SVF or α), fluid flow face velocity (mean inlet velocity), and filter thickness (I x ), on pressure drop and deposition efficiency are researched. Furthermore, to study the effects of variation of the laminar flow regime and fiber’s cross-sectional shape on the deposition of particles, only a single square fiber has been placed in a channel. By means of finite volume method (FVM), the 2-D motion of 100–1000 nm particles was investigated numerically. The Lagrangian method has been employed and the Saffman’s lift, Drag, and Brownian forces have been considered to affect this motion. Contribution of increasing the Reynolds number to filtration performance increased with smaller fine aerosols to a level of 59.72 %. However, for over 500 nm, the Re = 100 has more efficient results up to 26.97 %. Remarkably, the single square fiber in Re = 200 regime performs similarly to the optimum choice of multi-fibrous filters. It was portrayed the parallel circular multi-fibrous filter with a ratio of horizontal-to-vertical distances between fibers, l/h = 1.143; α = 0.687, I x = 116.572, and h/d f = 1.0 is the most efficient filter’s structure. The increase in the ratio of vertical distances between fibers-to-fiber’s diameter (h/d f ) and decrease in SVF or α, results in a drastically decrement of the filtration performance of both parallel and staggered structures. The obtained results have been validated with previous research findings. 相似文献
996.
Wireless Networks - In a wireless sensor network (WSN), there is always the possibility of failure in sensor nodes. Quality of Service (QoS) of WSNs is highly degraded due to the faulty sensor... 相似文献
997.
Golsorkhtabaramiri Mehdi Issazadehkojidi Neda Pouresfehani Negin Mohammadialamoti Maryam Hosseinzadehsadati Seyyed Mehrdad 《Wireless Networks》2019,25(5):2393-2406
Wireless Networks - Radio-frequency identification (RFID) is known as a universal technology and has been in the center of attention in the past few years. Readers and tags constitute the main... 相似文献
998.
Aynehband Meghdad Hosseinzadeh Mehdi Zarrabi Houman Gorgin Saeed 《Wireless Networks》2019,25(7):4299-4317
Wireless Networks - As Social networks are widely used by the people around the world, if this infrastructure can be used for event detection systems like fire forest detection, the overall cost of... 相似文献
999.
Vahabi Shahrokh Eslaminejad Mohammadreza Dashti Seyed Ebrahim 《Wireless Networks》2019,25(5):2953-2961
Wireless Networks - Wireless sensor networks (WSNs) is used for the internet of things, and Pervasive/Ubiquitous computing. These networks consist of intelligent nodes which sense data and forward... 相似文献
1000.
Telecommunication Systems - In the original version of this article, unfortunately, there are mistakes in some formulas for determining the number of true different cubic, fourth degree, and fifth... 相似文献