Pub Date : 2023-10-17DOI: 10.24200/sci.2023.53774.3405
Xin Ma, Wenqing Wu, Yuanyuan Zhang
The discrete grey modelling technique is a novel methodology of grey predictionmodels, which is effective to improve the effectiveness and applicability of greymodels. In order to build a more general and effective univariate grey predictionmodel, the discrete grey modelling technique is utilised in this paper to builda quadratic polynomial discrete grey model, abbreviated as the QPDGM. Theproperties of the QPDGM model have been discussed, which indicate that thenew model can be regarded as an extension of the conventional discrete greymodel and nonhomogeneous grey model, and it is also coincidence with threeclasses of exponential sequences. The QPDGM model is finally applied to predictthe energy consumption of China, including the electric power, crude oil andnatural gas consumptions. The results have been compared to some commonlyused univariate grey prediction models, which indicates the QPDGM model isgenerally more accurate than other models.
{"title":"Application of a novel quadratic polynomial discrete grey model to forecast energy consumption of China","authors":"Xin Ma, Wenqing Wu, Yuanyuan Zhang","doi":"10.24200/sci.2023.53774.3405","DOIUrl":"https://doi.org/10.24200/sci.2023.53774.3405","url":null,"abstract":"The discrete grey modelling technique is a novel methodology of grey predictionmodels, which is effective to improve the effectiveness and applicability of greymodels. In order to build a more general and effective univariate grey predictionmodel, the discrete grey modelling technique is utilised in this paper to builda quadratic polynomial discrete grey model, abbreviated as the QPDGM. Theproperties of the QPDGM model have been discussed, which indicate that thenew model can be regarded as an extension of the conventional discrete greymodel and nonhomogeneous grey model, and it is also coincidence with threeclasses of exponential sequences. The QPDGM model is finally applied to predictthe energy consumption of China, including the electric power, crude oil andnatural gas consumptions. The results have been compared to some commonlyused univariate grey prediction models, which indicates the QPDGM model isgenerally more accurate than other models.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136078481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-17DOI: 10.24200/sci.2023.61173.7179
Munazza Saeed, Bilal Ahmad, Chemseddine Maatki, Tasawar Abbas, Bilel Hadrich, Sami Ullah Khan, Karim Kriaa, Qazi Mehmood Ul-Hassan, Lioua Kolsi
This investigation presents the heat and mass transfer phenomenon for the chemically reactive flow of second grade fluid subject to the homogeneous and heterogeneous (HH) chemical reactions. The viscosity of fluid is assumed to be temperature dependent instead of constant. The motivations for considering the viscosity as a function of temperature is justified with applications of metallurgical process, crude oil extraction, geothermal systems and machinery lubrication. Additionally, viscous dissipation and temperature dependent heat generation and absorption effects are also introduced to improve the thermal transportation phenomenon. The interaction of different new variables facilitates the problem into dimensionless form. The numerical achievements are predicted with implementing the Runge Kutta (RK4) method. The physical onset behind the parameters have been reported. The tabular quantitative analysis is performed for different physical quantities.
{"title":"Temperature dependent heat generation and variable viscosity features for viscoelastic fluid with homogeneous and heterogeneous (HH) chemical reactions","authors":"Munazza Saeed, Bilal Ahmad, Chemseddine Maatki, Tasawar Abbas, Bilel Hadrich, Sami Ullah Khan, Karim Kriaa, Qazi Mehmood Ul-Hassan, Lioua Kolsi","doi":"10.24200/sci.2023.61173.7179","DOIUrl":"https://doi.org/10.24200/sci.2023.61173.7179","url":null,"abstract":"This investigation presents the heat and mass transfer phenomenon for the chemically reactive flow of second grade fluid subject to the homogeneous and heterogeneous (HH) chemical reactions. The viscosity of fluid is assumed to be temperature dependent instead of constant. The motivations for considering the viscosity as a function of temperature is justified with applications of metallurgical process, crude oil extraction, geothermal systems and machinery lubrication. Additionally, viscous dissipation and temperature dependent heat generation and absorption effects are also introduced to improve the thermal transportation phenomenon. The interaction of different new variables facilitates the problem into dimensionless form. The numerical achievements are predicted with implementing the Runge Kutta (RK4) method. The physical onset behind the parameters have been reported. The tabular quantitative analysis is performed for different physical quantities.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136039753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-17DOI: 10.24200/sci.2023.60185.6650
Ali Mehrvar, Mohsen Motamedi, Abouzar Jamalpour
Modeling and determining the optimal conditions for the jet electrochemical machining (Jet-ECM) process is critical. In this study, a hybrid approach combining numerical and design of experiments (DOE) methods have been applied to model and determine the optimal conditions for Jet-ECM. The voltage (V), inner tool diameter (I), initial machining gap (G), and electrolyte conductivity (C) are considered input variables. Additionally, dimensional accuracy (E) and machining depth (D) are response variables. Twenty-seven numerical simulations have been performed using the Box–Behnken design to implement the response surface methodology (RSM). Consequently, two mathematical models have been obtained for these response variables. The effects of the input variables on the response variables are investigated using statistical techniques such as variance analysis. Furthermore, the desirability function approach has been applied to determine the optimal conditions for dimensional accuracy and depth of machining. The results show that the optimal values for achieving maximum depth of machining while maintaining a dimensional accuracy of 0.05 mm are as follows: electrolyte conductivity of 8 S/m, voltage of 36.9 V, initial machining gap of 200 μm, and inner tool diameter of 0.4 mm.
{"title":"Modeling of Jet Electrochemical Machining Using Numerical and Design of Experiments Methods","authors":"Ali Mehrvar, Mohsen Motamedi, Abouzar Jamalpour","doi":"10.24200/sci.2023.60185.6650","DOIUrl":"https://doi.org/10.24200/sci.2023.60185.6650","url":null,"abstract":"Modeling and determining the optimal conditions for the jet electrochemical machining (Jet-ECM) process is critical. In this study, a hybrid approach combining numerical and design of experiments (DOE) methods have been applied to model and determine the optimal conditions for Jet-ECM. The voltage (V), inner tool diameter (I), initial machining gap (G), and electrolyte conductivity (C) are considered input variables. Additionally, dimensional accuracy (E) and machining depth (D) are response variables. Twenty-seven numerical simulations have been performed using the Box–Behnken design to implement the response surface methodology (RSM). Consequently, two mathematical models have been obtained for these response variables. The effects of the input variables on the response variables are investigated using statistical techniques such as variance analysis. Furthermore, the desirability function approach has been applied to determine the optimal conditions for dimensional accuracy and depth of machining. The results show that the optimal values for achieving maximum depth of machining while maintaining a dimensional accuracy of 0.05 mm are as follows: electrolyte conductivity of 8 S/m, voltage of 36.9 V, initial machining gap of 200 μm, and inner tool diameter of 0.4 mm.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136078460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-17DOI: 10.24200/sci.2023.62539.7901
Hamed Lasjerdi, Zahra Nasiri-Gheidari
Variable reluctance resolver is one of the popular sensors used in the industry. Because they can operate at high temperatures, withstand shock and less expensive and easier to manufacture. Despite the mentioned advantages, the variable reluctance resolver may suffer from faults that lead to inaccurate position. The paper aims to reduce position error under short circuit fault by changing parameters such as excitation frequency, number of signal and excitation poles, shape of the air gap, slot opening width and the number of teeth. The effect of each parameter on reducing the position error is examined to determine whether it has a positive, a negative or zero effect. Finally, the optimal case is introduced by selecting the best value for each parameter, which significantly reduces the position error.
{"title":"Improving the Performance of Variable Reluctance Resolver Against Short Circuit Using Physical Parameters","authors":"Hamed Lasjerdi, Zahra Nasiri-Gheidari","doi":"10.24200/sci.2023.62539.7901","DOIUrl":"https://doi.org/10.24200/sci.2023.62539.7901","url":null,"abstract":"Variable reluctance resolver is one of the popular sensors used in the industry. Because they can operate at high temperatures, withstand shock and less expensive and easier to manufacture. Despite the mentioned advantages, the variable reluctance resolver may suffer from faults that lead to inaccurate position. The paper aims to reduce position error under short circuit fault by changing parameters such as excitation frequency, number of signal and excitation poles, shape of the air gap, slot opening width and the number of teeth. The effect of each parameter on reducing the position error is examined to determine whether it has a positive, a negative or zero effect. Finally, the optimal case is introduced by selecting the best value for each parameter, which significantly reduces the position error.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":"20 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136039751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-17DOI: 10.24200/sci.2023.62495.7870
Iraj Ahadzadeh, Samira Dabbagh
A cost-effective piezoresistive sensor based on PVC/Reduced graphene oxide (rGO) was fabricated and its performance was investigated. The weight percent range from 0.1 to 30% of rGO in PVC matrix was studied. Composite parts were prepared by using the solution casting method from tetrahydrofurane (THF) solvent followed by solvent evaporation. The plot of electrical conduction versus rGO percentage was constructed to obtain the percolation threshold concentration. It was found that the percolation threshold of rGO leading to a continuous stable electrical conductivity in PVC matrix is about 25% beyond which electrical resistance was reduced from about 800 GΩ to lower than 100 KΩ range. The relative changes in electrical resistance of prepared polymer parts as a result of impact (stress), stretch and bending deformation were studied. The results showed that the fabricated composite can be used for sensing and/or monitoring and measurement of any mechanical displacement with high sensitivity, promising reproducibility and satisfactory durability. It must be mentioned that, during impact tests of polymer composites, a small piezoelectric effect was also observed for which further complimentary studies are being planned to be performed in near future in order to better understand this effect and its underlining molecular basis.
{"title":"Fabrication of a Cost-effective Piezoresistive Pressure Sensor Based on PVC/Reduced Graphene Oxide (rGO) Composite","authors":"Iraj Ahadzadeh, Samira Dabbagh","doi":"10.24200/sci.2023.62495.7870","DOIUrl":"https://doi.org/10.24200/sci.2023.62495.7870","url":null,"abstract":"A cost-effective piezoresistive sensor based on PVC/Reduced graphene oxide (rGO) was fabricated and its performance was investigated. The weight percent range from 0.1 to 30% of rGO in PVC matrix was studied. Composite parts were prepared by using the solution casting method from tetrahydrofurane (THF) solvent followed by solvent evaporation. The plot of electrical conduction versus rGO percentage was constructed to obtain the percolation threshold concentration. It was found that the percolation threshold of rGO leading to a continuous stable electrical conductivity in PVC matrix is about 25% beyond which electrical resistance was reduced from about 800 GΩ to lower than 100 KΩ range. The relative changes in electrical resistance of prepared polymer parts as a result of impact (stress), stretch and bending deformation were studied. The results showed that the fabricated composite can be used for sensing and/or monitoring and measurement of any mechanical displacement with high sensitivity, promising reproducibility and satisfactory durability. It must be mentioned that, during impact tests of polymer composites, a small piezoelectric effect was also observed for which further complimentary studies are being planned to be performed in near future in order to better understand this effect and its underlining molecular basis.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136078478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-17DOI: 10.24200/sci.2023.61477.7330
Basir Rashedi, Amir Abdollahi, Masoud Rashidinejad
In this paper, the quantitative flexibility of EH is evaluated considering a flexibility index which is based upon available maximum capacity as well as the response time of generating units. Here, the impact of simultaneous EH operation and construction are investigated on quantitative flexibility considering both uncertain supply and demand side resources. Hence, a new structure so-called multi-objective simultaneous operation/construction optimization of multi-carrier EH is presented which consists of a decrease in operation and construction costs as well increase in power system flexibility. The demand side uncertainties, including thermal/electrical demand, are implemented by the Gaussian distribution function, and uncertainty on the supply side, including gas pressure uncertainty (GPU), is modeled by the probabilistic–possibilistic Z-number method. Also, in multifarious cases, the performance of the proposed index is evaluated. It is shown how flexible resources like electrical storage systems (ESS), thermal storage systems (TSS), electrical demand response programs (EDRP), and thermal demand response programs (TDRP) can increase the flexibility of the EH. It is also conducted that how the flexibility enhancement can increase construction costs.
{"title":"Simultaneous energy hub operation and construction for investigating quantitative flexibility considering uncertain supply and demand side resources","authors":"Basir Rashedi, Amir Abdollahi, Masoud Rashidinejad","doi":"10.24200/sci.2023.61477.7330","DOIUrl":"https://doi.org/10.24200/sci.2023.61477.7330","url":null,"abstract":"In this paper, the quantitative flexibility of EH is evaluated considering a flexibility index which is based upon available maximum capacity as well as the response time of generating units. Here, the impact of simultaneous EH operation and construction are investigated on quantitative flexibility considering both uncertain supply and demand side resources. Hence, a new structure so-called multi-objective simultaneous operation/construction optimization of multi-carrier EH is presented which consists of a decrease in operation and construction costs as well increase in power system flexibility. The demand side uncertainties, including thermal/electrical demand, are implemented by the Gaussian distribution function, and uncertainty on the supply side, including gas pressure uncertainty (GPU), is modeled by the probabilistic–possibilistic Z-number method. Also, in multifarious cases, the performance of the proposed index is evaluated. It is shown how flexible resources like electrical storage systems (ESS), thermal storage systems (TSS), electrical demand response programs (EDRP), and thermal demand response programs (TDRP) can increase the flexibility of the EH. It is also conducted that how the flexibility enhancement can increase construction costs.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":"503 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136039754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-17DOI: 10.24200/sci.2023.59611.6337
David Mahlangu, Olufemi Adetunji, Makoena Sebatjane
We present an inventory model to determine the optimal selling price and cycle time for two mutually complementary commodities that are subject to deterioration. Each commodity's demand is influenced by its own selling price, the selling price of the complementary product, and the passage of time. Numerical examples and sensitivity analysis results are presented to demonstrate the usefulness of the inventory model. We conducted sensitivity analysis on the impacts of the changes in key parameters of the model on the decision variables and the objective (profitability) of the inventory system. We observed that as the deterioration rate of either item increases, the model proposes shorter replenishment cycle length, which reduces the profit. Our model’s novelty is the inclusion of mutual (two-way) complementarity in the Economic Order Quantity model, where both items are deteriorating and have time-dependent demands.
{"title":"An economic order quantity model for two deteriorating items with mutually complementary price and time dependent demand","authors":"David Mahlangu, Olufemi Adetunji, Makoena Sebatjane","doi":"10.24200/sci.2023.59611.6337","DOIUrl":"https://doi.org/10.24200/sci.2023.59611.6337","url":null,"abstract":"We present an inventory model to determine the optimal selling price and cycle time for two mutually complementary commodities that are subject to deterioration. Each commodity's demand is influenced by its own selling price, the selling price of the complementary product, and the passage of time. Numerical examples and sensitivity analysis results are presented to demonstrate the usefulness of the inventory model. We conducted sensitivity analysis on the impacts of the changes in key parameters of the model on the decision variables and the objective (profitability) of the inventory system. We observed that as the deterioration rate of either item increases, the model proposes shorter replenishment cycle length, which reduces the profit. Our model’s novelty is the inclusion of mutual (two-way) complementarity in the Economic Order Quantity model, where both items are deteriorating and have time-dependent demands.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136078300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-10DOI: 10.24200/sci.2023.62894.8090
Nima Salek Gilani, Alireza Fereidunian
This study intends to quantify, model and evaluate the impact of preventive maintenance (PM) on interruption duration (IntD) in electricity distribution systems, based on analyzing the data from the dashboard of an electricity distribution company and expert opinions. Following the data cleaning, the data are analyzed to identify the failure modes and their effects, to recognize the critical components (FMEA). Subsequently, the PM activities associated with them are investigated, to analyze the maintenance activities scheduling impact on IntD, employing expert judgment as a decision support. The data analysis reveals that the fuses and fuse holders experience the highest interruptions frequencies and durations, nominating them as critical components. Then, the impact of maintenance activity (inspection time) on the IntD percentage change is analyzed, leading to calculation of the sensitivity of IntD to maintenance activity. The quasi-linear shape of the IntD and ENS percentage decreases versus PM inspection time, i.e. the intended sensitivities is observed, thus two linear models are developed to represent this impact, suitable for maintenance optimization problems which need linear models convexity. Moreover, two indices of SIntDPM and SENSPM are introduced as maintenance KPIs representing the sensitivities, to prioritize PM actions versus their impact on IntD.
{"title":"A Phenomenological Approach to Analysis of Maintenance Activities Impact on Interruption Duration in Electricity Distribution Systems, based on Historical Data and Expert Judgment","authors":"Nima Salek Gilani, Alireza Fereidunian","doi":"10.24200/sci.2023.62894.8090","DOIUrl":"https://doi.org/10.24200/sci.2023.62894.8090","url":null,"abstract":"This study intends to quantify, model and evaluate the impact of preventive maintenance (PM) on interruption duration (IntD) in electricity distribution systems, based on analyzing the data from the dashboard of an electricity distribution company and expert opinions. Following the data cleaning, the data are analyzed to identify the failure modes and their effects, to recognize the critical components (FMEA). Subsequently, the PM activities associated with them are investigated, to analyze the maintenance activities scheduling impact on IntD, employing expert judgment as a decision support. The data analysis reveals that the fuses and fuse holders experience the highest interruptions frequencies and durations, nominating them as critical components. Then, the impact of maintenance activity (inspection time) on the IntD percentage change is analyzed, leading to calculation of the sensitivity of IntD to maintenance activity. The quasi-linear shape of the IntD and ENS percentage decreases versus PM inspection time, i.e. the intended sensitivities is observed, thus two linear models are developed to represent this impact, suitable for maintenance optimization problems which need linear models convexity. Moreover, two indices of SIntDPM and SENSPM are introduced as maintenance KPIs representing the sensitivities, to prioritize PM actions versus their impact on IntD.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136360806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-09DOI: 10.24200/sci.2023.60289.6706
Zahra Fatemi, Seyed Jafar Sadjadi, Armin Jabbarzadeh, Ahmad Makui
To maintain a competitive advantage, manufacturers of household appliances should promote the product’s energy efficiency, considering the impact on customer purchasing behavior. Since the product’s energy efficiency and pricing policies influence customers’ purchasing decisions, manufacturers confront significant challenges in balancing costs and demand since they must consider their profit-maximizing objective and government regulations. The Stackelberg game framework represents the interactions between the government, the leader, and a manufacturer, the follower, incorporating the government’s involvement in environmentally dependent social welfare under a tax structure. This paper proposes closed-form equilibrium using a game theory approach and geometric programming (GP) to solve the government’s and manufacturers’ non-linear decision models. The analytical results offer insight into the management’s approach to the product’s energy efficiency. The findings demonstrate that when clients’ concerns about energy-saving grow, the net payoff to the total manufacturer revenue ratio continuously decreases. The outcomes imply that the manufacturer must allocate significant revenue to tax expenditures in markets with more price-sensitive clients. As a motivation for research, this paper explores the application of the proposed model by examining a numerical example of a real-world refrigerator manufacturer case to obtain further managerial insight.
{"title":"Investments in energy efficiency with government environmental sensitiveness: An application of geometric programming and game theory","authors":"Zahra Fatemi, Seyed Jafar Sadjadi, Armin Jabbarzadeh, Ahmad Makui","doi":"10.24200/sci.2023.60289.6706","DOIUrl":"https://doi.org/10.24200/sci.2023.60289.6706","url":null,"abstract":"To maintain a competitive advantage, manufacturers of household appliances should promote the product’s energy efficiency, considering the impact on customer purchasing behavior. Since the product’s energy efficiency and pricing policies influence customers’ purchasing decisions, manufacturers confront significant challenges in balancing costs and demand since they must consider their profit-maximizing objective and government regulations. The Stackelberg game framework represents the interactions between the government, the leader, and a manufacturer, the follower, incorporating the government’s involvement in environmentally dependent social welfare under a tax structure. This paper proposes closed-form equilibrium using a game theory approach and geometric programming (GP) to solve the government’s and manufacturers’ non-linear decision models. The analytical results offer insight into the management’s approach to the product’s energy efficiency. The findings demonstrate that when clients’ concerns about energy-saving grow, the net payoff to the total manufacturer revenue ratio continuously decreases. The outcomes imply that the manufacturer must allocate significant revenue to tax expenditures in markets with more price-sensitive clients. As a motivation for research, this paper explores the application of the proposed model by examining a numerical example of a real-world refrigerator manufacturer case to obtain further managerial insight.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135149683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-09DOI: 10.24200/sci.2023.60404.6783
Jamil Abbas Haider, Sana Gul, Sohail Nadeem
The peristaltic flow of nanofluids is a topic of growing interest in fluid dynamics. This study investigates the effect of temperature-dependent viscosity and electric conductivity on the peristaltic flow of nanofluids. The mathematical model of the peristaltic flow is developed using the governing equations of continuity, momentum, and energy for a Newtonian fluid. Large wavelength and small Reynolds number assumptions are used to study peristaltic flow to simplify the equations of continuity, momentum, and energy. In this article, the nanofluids are assumed to be electrically conducting and temperature dependent, and the effects of Hartman number and Eckert number is studied. The resulting equations are solved using the Shooting Method. The results show that the temperature-dependent viscosity and electric conductivity significantly affect the peristaltic flow of nanofluids. The flow rate and pressure gradient decrease with increasing viscosity and conductivity while the temperature and heat transfer rate increase. Moreover, the nanofluid concentration and particle size significantly impact the flow characteristics. In conclusion, this study comprehensively analyses the peristaltic flow of nanofluids with temperature-dependent viscosity and electric conductivity. The results can be useful for understanding the behaviour of nanofluids in various applications, such as drug delivery systems, microfluidics, and thermal management.
{"title":"Numerical Investigation of the Heat Transfer and Peristaltic Flow Through a Asymmetric Channel Having Variable Viscosity and Electric Conductivity","authors":"Jamil Abbas Haider, Sana Gul, Sohail Nadeem","doi":"10.24200/sci.2023.60404.6783","DOIUrl":"https://doi.org/10.24200/sci.2023.60404.6783","url":null,"abstract":"The peristaltic flow of nanofluids is a topic of growing interest in fluid dynamics. This study investigates the effect of temperature-dependent viscosity and electric conductivity on the peristaltic flow of nanofluids. The mathematical model of the peristaltic flow is developed using the governing equations of continuity, momentum, and energy for a Newtonian fluid. Large wavelength and small Reynolds number assumptions are used to study peristaltic flow to simplify the equations of continuity, momentum, and energy. In this article, the nanofluids are assumed to be electrically conducting and temperature dependent, and the effects of Hartman number and Eckert number is studied. The resulting equations are solved using the Shooting Method. The results show that the temperature-dependent viscosity and electric conductivity significantly affect the peristaltic flow of nanofluids. The flow rate and pressure gradient decrease with increasing viscosity and conductivity while the temperature and heat transfer rate increase. Moreover, the nanofluid concentration and particle size significantly impact the flow characteristics. In conclusion, this study comprehensively analyses the peristaltic flow of nanofluids with temperature-dependent viscosity and electric conductivity. The results can be useful for understanding the behaviour of nanofluids in various applications, such as drug delivery systems, microfluidics, and thermal management.","PeriodicalId":21605,"journal":{"name":"Scientia Iranica","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135149374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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