Pub Date : 2021-01-01DOI: 10.3844/ajeassp.2021.152.161
H. Elhegazy, A. Ebid, I. Mahdi, S. Haggag, I. A. Rashid
Corresponding author: Hosam Elhegazy Department of Structural Engineering and Construction Management, Faculty of Engineering and Technology, Future University in Egypt, Egypt Email: hossam.mostaffa@fue.edu.eg Abstract: There are numerous structural lateral systems used in multistory buildings design such as the shear wall, frame system, framed with core, dual systems and superframes, etc. Additionally, the system of slabs such as (Solid Slab, Flat Slab, Flat plates, Hollow blocks, ... and Waffle Slabs). Generally, the structural systems of multi-story buildings are considered to be different types. Multi-story buildings are commonly used in residential, commercial and administrative projects; therefore, determining the structural system with minimum cost is the top priority of the structural designer. This research aims to introduce recommendations for the optimum structural system for a multi-story Reinforced Concrete (R.C.) building from a perspective of direct cost to help decision-makers in the preliminary design for choosing the optimum structural system. This paper outlines the development of charts to predict optimal structural system costing, using the status of early conceptual design as the charts input. In order to achieve that goal, a parametric study was carried out using 27 RC buildings with several stories ranging between 5 to 50 floors and grid spacing ranged between 6.0 to 12.0 m. Three floor systems were considered which are solid, ribbed and flat slabs.
{"title":"Decision Making and Predicting the Cost for the Optimal Structural System of Multi-Story Buildings","authors":"H. Elhegazy, A. Ebid, I. Mahdi, S. Haggag, I. A. Rashid","doi":"10.3844/ajeassp.2021.152.161","DOIUrl":"https://doi.org/10.3844/ajeassp.2021.152.161","url":null,"abstract":"Corresponding author: Hosam Elhegazy Department of Structural Engineering and Construction Management, Faculty of Engineering and Technology, Future University in Egypt, Egypt Email: hossam.mostaffa@fue.edu.eg Abstract: There are numerous structural lateral systems used in multistory buildings design such as the shear wall, frame system, framed with core, dual systems and superframes, etc. Additionally, the system of slabs such as (Solid Slab, Flat Slab, Flat plates, Hollow blocks, ... and Waffle Slabs). Generally, the structural systems of multi-story buildings are considered to be different types. Multi-story buildings are commonly used in residential, commercial and administrative projects; therefore, determining the structural system with minimum cost is the top priority of the structural designer. This research aims to introduce recommendations for the optimum structural system for a multi-story Reinforced Concrete (R.C.) building from a perspective of direct cost to help decision-makers in the preliminary design for choosing the optimum structural system. This paper outlines the development of charts to predict optimal structural system costing, using the status of early conceptual design as the charts input. In order to achieve that goal, a parametric study was carried out using 27 RC buildings with several stories ranging between 5 to 50 floors and grid spacing ranged between 6.0 to 12.0 m. Three floor systems were considered which are solid, ribbed and flat slabs.","PeriodicalId":7425,"journal":{"name":"American Journal of Engineering and Applied Sciences","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73195973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.3844/AJEASSP.2021.7.24
R. Torre, S. Brischetto
Strain gauges are ordinary transducers for strain measuring; their operation relies on the electrical resistance, which varies as the underlying substrate is subjected to mechanical deformation. The mechanical strain can be obtained by converting the electrical signal through a gauge factor, provided by the manufacturer. It was demonstrated that its values are not unique; it may be influenced by the geometrical characteristics of both the specimen and the strain gauge and by their respective moduli of elasticity. This can be extremely dangerous when low modulus materials are studied. This study confirms that even with commercial strain gauges specifically designed for low modulus materials the effect might be present. An experimental method for its evaluation is discussed; tensile specimens are used as a test bench and their modulus is determined using both strain gauges and a non-contact method (Digital Image Correlation). The results show that a local reinforcing effect is present and a higher tensile modulus is obtained when contact transducers are bonded to polymeric specimens. The amplitude of this effect is predicted with established methods available in the literature and through a simple 2D Finite Element (FE) model. All these models require the elastic modulus of the strain gauge to be considered; a digital procedure to estimate it for any wired transducer is therefore proposed. The predicted results were found to be consistent with those experimentally measured; this validated the method, thus advising on how to evaluate the phenomenon also when this information is not available.
{"title":"Reinforcing Effect of Strain Gauges on 3D Printed Polymers: An Experimental Investigation","authors":"R. Torre, S. Brischetto","doi":"10.3844/AJEASSP.2021.7.24","DOIUrl":"https://doi.org/10.3844/AJEASSP.2021.7.24","url":null,"abstract":"Strain gauges are ordinary transducers for strain measuring; their operation relies on the electrical resistance, which varies as the underlying substrate is subjected to mechanical deformation. The mechanical strain can be obtained by converting the electrical signal through a gauge factor, provided by the manufacturer. It was demonstrated that its values are not unique; it may be influenced by the geometrical characteristics of both the specimen and the strain gauge and by their respective moduli of elasticity. This can be extremely dangerous when low modulus materials are studied. This study confirms that even with commercial strain gauges specifically designed for low modulus materials the effect might be present. An experimental method for its evaluation is discussed; tensile specimens are used as a test bench and their modulus is determined using both strain gauges and a non-contact method (Digital Image Correlation). The results show that a local reinforcing effect is present and a higher tensile modulus is obtained when contact transducers are bonded to polymeric specimens. The amplitude of this effect is predicted with established methods available in the literature and through a simple 2D Finite Element (FE) model. All these models require the elastic modulus of the strain gauge to be considered; a digital procedure to estimate it for any wired transducer is therefore proposed. The predicted results were found to be consistent with those experimentally measured; this validated the method, thus advising on how to evaluate the phenomenon also when this information is not available.","PeriodicalId":7425,"journal":{"name":"American Journal of Engineering and Applied Sciences","volume":"41 1","pages":"7-24"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82677612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.3844/AJEASSP.2021.51.63
Hamid Ranjkesh Adarmanabadi, A. Rasti, M. Razavi
Electrical resistivity is a non-destructive, cost-effective and sensitive method to evaluate soil's physical and chemical properties. Electrical resistivity has been used widely in surface and subsurface exploration. The electrical resistivity is directly related to the subsurface geotechnical and geothermal properties like porosity, temperature, salinity and water content. Recently uses of waste material as an additive to improve the soil engineering properties are growing because of their cost-effectiveness. Cement Kiln Dust (CKD) is a waste material of the cement manufacturing process. CKD is widely used as an additive material in ground improvement to improve soil's geotechnical properties. This study is mainly focused on the effect of CKD on the electrical resistivity properties of the soil. In this study, the electrical resistivity of a natural soil slope treated with CKD and a test model in the laboratory was investigated. Besides, the effects of CKD on soil pH and electrical resistivity were studied by performing a series of tests to predict the soil's corrosivity potential. The soil was treated with 0, 5, 10 and 15% of CKD and the electrical resistivity of the soil was measured at different water contents, porosities and curing times. The results indicate that the soil's electrical resistivity increases by increasing the CKD content and curing time. Additionally, an increase in water content or porosity decreases the electrical resistivity of CKD treated soil. Furthermore, the electrical resistivity measurement is a practical method to determine the stabilized soil's geotechnical and geomechanical properties.
{"title":"The Effects of Cement Kiln Dust on the Soil Electrical Resistivity","authors":"Hamid Ranjkesh Adarmanabadi, A. Rasti, M. Razavi","doi":"10.3844/AJEASSP.2021.51.63","DOIUrl":"https://doi.org/10.3844/AJEASSP.2021.51.63","url":null,"abstract":"Electrical resistivity is a non-destructive, cost-effective and sensitive method to evaluate soil's physical and chemical properties. Electrical resistivity has been used widely in surface and subsurface exploration. The electrical resistivity is directly related to the subsurface geotechnical and geothermal properties like porosity, temperature, salinity and water content. Recently uses of waste material as an additive to improve the soil engineering properties are growing because of their cost-effectiveness. Cement Kiln Dust (CKD) is a waste material of the cement manufacturing process. CKD is widely used as an additive material in ground improvement to improve soil's geotechnical properties. This study is mainly focused on the effect of CKD on the electrical resistivity properties of the soil. In this study, the electrical resistivity of a natural soil slope treated with CKD and a test model in the laboratory was investigated. Besides, the effects of CKD on soil pH and electrical resistivity were studied by performing a series of tests to predict the soil's corrosivity potential. The soil was treated with 0, 5, 10 and 15% of CKD and the electrical resistivity of the soil was measured at different water contents, porosities and curing times. The results indicate that the soil's electrical resistivity increases by increasing the CKD content and curing time. Additionally, an increase in water content or porosity decreases the electrical resistivity of CKD treated soil. Furthermore, the electrical resistivity measurement is a practical method to determine the stabilized soil's geotechnical and geomechanical properties.","PeriodicalId":7425,"journal":{"name":"American Journal of Engineering and Applied Sciences","volume":"12 1","pages":"51-63"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87975745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.3844/AJEASSP.2021.139.151
A. Piroddi, M. Torregiani
One of the most complex challenges that wireless communication systems will face in the coming years is the management of the radio resource. In the next years, the growth of mobile devices, forecast (CISCO, 2020), will lead to the coexistence of about 8.8 billion mobile devices with a growing trend for the following years. This scenario makes the reuse of the radio resource particularly critical, which for its part will not undergo significant changes in terms of bandwidth availability. One of the biggest problems to be faced will be to identify solutions that optimize its use. This work shows how a combined approach of a Reinforcement Learning model and a Supervised Learning model (Multi-Layer Perceptron) can provide good performance in the prediction of the channel behavior and on the overall performance of the transmission chain, even for Cognitive Radio with limited computational power, such as NB-IoT, LoRaWan, Sigfox.
{"title":"Combining Q-Learning and Multi-Layer Perceptron Models on Wireless Channel Quality Prediction","authors":"A. Piroddi, M. Torregiani","doi":"10.3844/AJEASSP.2021.139.151","DOIUrl":"https://doi.org/10.3844/AJEASSP.2021.139.151","url":null,"abstract":"One of the most complex challenges that wireless communication systems will face in the coming years is the management of the radio resource. In the next years, the growth of mobile devices, forecast (CISCO, 2020), will lead to the coexistence of about 8.8 billion mobile devices with a growing trend for the following years. This scenario makes the reuse of the radio resource particularly critical, which for its part will not undergo significant changes in terms of bandwidth availability. One of the biggest problems to be faced will be to identify solutions that optimize its use. This work shows how a combined approach of a Reinforcement Learning model and a Supervised Learning model (Multi-Layer Perceptron) can provide good performance in the prediction of the channel behavior and on the overall performance of the transmission chain, even for Cognitive Radio with limited computational power, such as NB-IoT, LoRaWan, Sigfox.","PeriodicalId":7425,"journal":{"name":"American Journal of Engineering and Applied Sciences","volume":"36 1","pages":"139-151"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77468516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.3844/AJEASSP.2021.25.50
Mebougna L. Drabo, S. Budak, S. Egarievwe, Richard Lagle
Multilayered thermoelectric Sn/Sn+SnO2 thin films were prepared using KJL DC/RF magnetron sputtering system under Ar gas plasma on the SiO2 substrates. The thicknesses of the fabricated thin films were found using Filmetrics UV thickness measurement system. The fabricated thin films were annealed at different temperatures for one hour to tailor the thermoelectric properties. In this study, unannealed, annealed at 150 and 300°C samples were characterized using Thermo Fisher XPS system brought to the Alabama A&M University by the NSF-MRI support. X-ray Photoelectron Spectroscopy (XPS), also known as Electron Spectroscopy for Chemical Analysis (ESCA) is a type of analysis used for characterization of various surface materials. XPS is mostly known for the characterization of thin films-which are coatings that have been deposited onto a substrate and may be comprised of many different materials to alter or enhance the substrate’s performance. XPS analysis provides information for composition, chemical states, depth profile, imaging and thickness of thin film. This paper focuses on the application of XPS techniques in thin film research for Sn/Sn+SnO2 multilayered thermoelectric system and SiO2 substrates annealed at different temperatures. Since SiO2 substrates were used during the deposition of the multilayer thin films, we would like to perform detailed XPS studies on the SiO2 substrates. SiO2 substrates is being used with many researchers, this manuscript will be good reference for the researchers using SiO2 substrates. Thermal treatment of the substrates and the multilayered thin films has caused some changes of the XPS characterization including binding energy, depth profile, peak value and FWHM. The treatment effects were discussed and compared to each other.
{"title":"XPS Studies of the SiO2 Substrates and Thermoelectric Thin Films of Sn/Sn+SnO2 under the Effects of the Different Thermal Treatments","authors":"Mebougna L. Drabo, S. Budak, S. Egarievwe, Richard Lagle","doi":"10.3844/AJEASSP.2021.25.50","DOIUrl":"https://doi.org/10.3844/AJEASSP.2021.25.50","url":null,"abstract":"Multilayered thermoelectric Sn/Sn+SnO2 thin films were prepared using KJL DC/RF magnetron sputtering system under Ar gas plasma on the SiO2 substrates. The thicknesses of the fabricated thin films were found using Filmetrics UV thickness measurement system. The fabricated thin films were annealed at different temperatures for one hour to tailor the thermoelectric properties. In this study, unannealed, annealed at 150 and 300°C samples were characterized using Thermo Fisher XPS system brought to the Alabama A&M University by the NSF-MRI support. X-ray Photoelectron Spectroscopy (XPS), also known as Electron Spectroscopy for Chemical Analysis (ESCA) is a type of analysis used for characterization of various surface materials. XPS is mostly known for the characterization of thin films-which are coatings that have been deposited onto a substrate and may be comprised of many different materials to alter or enhance the substrate’s performance. XPS analysis provides information for composition, chemical states, depth profile, imaging and thickness of thin film. This paper focuses on the application of XPS techniques in thin film research for Sn/Sn+SnO2 multilayered thermoelectric system and SiO2 substrates annealed at different temperatures. Since SiO2 substrates were used during the deposition of the multilayer thin films, we would like to perform detailed XPS studies on the SiO2 substrates. SiO2 substrates is being used with many researchers, this manuscript will be good reference for the researchers using SiO2 substrates. Thermal treatment of the substrates and the multilayered thin films has caused some changes of the XPS characterization including binding energy, depth profile, peak value and FWHM. The treatment effects were discussed and compared to each other.","PeriodicalId":7425,"journal":{"name":"American Journal of Engineering and Applied Sciences","volume":"1 1","pages":"25-50"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78588893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.3844/AJEASSP.2021.73.80
Mohammad Najjartabar Bisheh, Abbas Raissi, Saeedeh Mokhtari
Business intelligence tools now play an important role in data collection, processing and analyses of organizations. Managers may use outputs of such tools and make improved decisions. To provide an even better situation for managers, business intelligence tools may be used to predict future and display present and past statuses of the organization. Available business intelligence tools predict future based on historical data, i.e., they are said to enjoy backward approaches. In this study, it was tried to change extrapolation of historical trends according to our expectations of future events so that forward approaches could be employed for prediction purposes.
{"title":"Combination of Backward and Forward Approaches for Future Prediction by Business Intelligence Tools","authors":"Mohammad Najjartabar Bisheh, Abbas Raissi, Saeedeh Mokhtari","doi":"10.3844/AJEASSP.2021.73.80","DOIUrl":"https://doi.org/10.3844/AJEASSP.2021.73.80","url":null,"abstract":"Business intelligence tools now play an important role in data collection, processing and analyses of organizations. Managers may use outputs of such tools and make improved decisions. To provide an even better situation for managers, business intelligence tools may be used to predict future and display present and past statuses of the organization. Available business intelligence tools predict future based on historical data, i.e., they are said to enjoy backward approaches. In this study, it was tried to change extrapolation of historical trends according to our expectations of future events so that forward approaches could be employed for prediction purposes.","PeriodicalId":7425,"journal":{"name":"American Journal of Engineering and Applied Sciences","volume":"24 1","pages":"73-80"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84774584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.3844/ajeassp.2021.351.363
G. Gregori, G. Paparo
{"title":"Time-Resolution of Climate Change Monitoring Volcanic Cycles, Stromboli, Ocean Floor Biota and Pandemics (?)","authors":"G. Gregori, G. Paparo","doi":"10.3844/ajeassp.2021.351.363","DOIUrl":"https://doi.org/10.3844/ajeassp.2021.351.363","url":null,"abstract":"","PeriodicalId":7425,"journal":{"name":"American Journal of Engineering and Applied Sciences","volume":"55 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76632550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.3844/AJEASSP.2021.1.6
A. Okassa, J. P. Ngantcha, A. Ndtoungou, P. Ele
In this study, we compress and decompress the vibration signals from the functioning of a ball bearing. The methodology used to compress the vibration data in this study is to reduce the size of the data by reducing the spectral redundancy of the samples. We have used the DCT, which is recognized for its representational parsimony and bleaching power. To reduce the execution time of the algorithm, we used the Lazy wavelet. This wavelet separates the original signal into two signals half the size of the original signal. Parallel processing of two halves of the original signal reduces the computational load of the algorithm. We tested (compressed and then decompressed) these signals using three compression algorithms separately under the same quantification and coding conditions. These are the algorithms based on DCT, WHT and the Lazy Wavelet associated with DCT. The comparison made on the basis of the measurements of SNR, MFD, MSE, PRD and CR allowed to retain the algorithm based on the use of the Lazy wavelet and the discrete cosine transform. The results are considered very encouraging.
{"title":"Use of Lazy Wavelet and DCT for Vibration Signal Compression","authors":"A. Okassa, J. P. Ngantcha, A. Ndtoungou, P. Ele","doi":"10.3844/AJEASSP.2021.1.6","DOIUrl":"https://doi.org/10.3844/AJEASSP.2021.1.6","url":null,"abstract":"In this study, we compress and decompress the vibration signals from the functioning of a ball bearing. The methodology used to compress the vibration data in this study is to reduce the size of the data by reducing the spectral redundancy of the samples. We have used the DCT, which is recognized for its representational parsimony and bleaching power. To reduce the execution time of the algorithm, we used the Lazy wavelet. This wavelet separates the original signal into two signals half the size of the original signal. Parallel processing of two halves of the original signal reduces the computational load of the algorithm. We tested (compressed and then decompressed) these signals using three compression algorithms separately under the same quantification and coding conditions. These are the algorithms based on DCT, WHT and the Lazy Wavelet associated with DCT. The comparison made on the basis of the measurements of SNR, MFD, MSE, PRD and CR allowed to retain the algorithm based on the use of the Lazy wavelet and the discrete cosine transform. The results are considered very encouraging.","PeriodicalId":7425,"journal":{"name":"American Journal of Engineering and Applied Sciences","volume":"513 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77852455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.3844/ajeassp.2021.398.408
D. Armand, Doko K. Valery, Wade Doukago Yacoubou Soumanou, Michozounnou Bénoît, Vianou Antoine
Corresponding Author: Djossou Ayihaou Armand Laboratory of Thermophysical Characterization of Materials and Energy Appropriation (Labo-CTMAE)-Polytechnic School of Abomey-Calavi (EPAC), 01 BP 2009 Cotonou (Benin) Email: ayihaou@yahoo.fr Abstract: To simultaneously meet the need of thermal confort and living environment protection, vegetable biomass valorisation in building sector is of particular importance. In this context, the main objective of this study is to produce a lightweight composite concrete based on millet pods and lateritic gravel with a cement matrix for use in buildings to help improve thermal comfort and protect environment. To achieve this, the composite formulation with 250 kg.m cement dosage and an 0.8 water to cement ratio was used to manufacture two type test specimens of (4 4 16) cm dimensions for porosity tests and (4 4 5) cm for thermal tests with a millet pod rate varying from 0 to 6% with a step of 2%. Average thermophysical characteristics of 5 tests carriesd out over 5 days, namely: Thermal conductivity, thermal diffusivity, thermal effusivity, thermal phase and damping, were experimentally measured using fluxmetric method similar to that of mini hot plate method with two Peltier elements as fluxmeters. Results obtained showed that for 0, 2, 4 and 6% millet pods dosage, thermal conductivity values obtained are respectively 1.18 W.m.K, 0.74 W.m.K, 0.63 W.m.K and 0.61 W.m.K, i.e., a reduction of 93.44%. For same millet pod dosage, thermal effusivity values are 2157.33 J.m.K.s, 1236.34 J.m.K.s, 946.03 J.m.K.s and 775.04 J.m.K.s, i.e., a reduction of 64.07%. On the other hand, it was observed 3.00.10 m.s, 3.56.10 m.s, 4.47.10 m.s and 6.25.10 m.s, i.e., an increase of 108.33% for thermal diffusivity. With regard to dynamiquc thermal characteristics, it was obtained an increase from 5.43 to 13.18% for thermal damping and, from 61.00 to 84.20 min for thermal phase. Through on the one hand, thermal conductivity and effusivity decrease and on the other hand, thermal damping and phase shift increase, it is retained that characterized eco-concrete should contribute to thermal losses limitation, energiy saving and improved thermal comfort.
通讯作者:Djossou Ayihaou Armand材料与能源占用热物理特性实验室(Labo-CTMAE)- Abomey-Calavi理工学院(EPAC)， 01 BP 2009 Cotonou(贝宁)Email: ayihaou@yahoo.fr摘要:为了同时满足热舒适和生活环境保护的需求，建筑领域的蔬菜生物质价值评价尤为重要。在这种背景下，本研究的主要目的是生产一种基于小米豆荚和红土砾石的轻质复合混凝土，并以水泥为基体，用于建筑中，以帮助改善热舒适性和保护环境。为实现这一目标，复合材料的配方为250公斤。水泥掺量为M，水灰比为0.8，分别制备了尺寸为(4416)cm和(445)cm的两种类型试样进行孔隙度试验和热试验，谷子荚率为0 ~ 6%，步长为2%。采用类似于微型热板法的通量法，以两个珀耳帖元件作为通量计，实验测量了5天内进行的5项试验的平均热物理特性:导热系数、热扩散系数、热渗出系数、热相和阻尼。结果表明，在添加量为0、2、4和6%时，谷子豆荚的导热系数分别为1.18、0.74、0.63和0.61，降低了93.44%。在相同谷子投加量下，热溢出率分别为2157.33、1236.34、946.03和775.04，降低了64.07%。另一方面，在3.00.10、3.56.10、4.47.10和6.25.10 m s时，热扩散系数增加了108.33%。动态热特性方面，热阻尼从5.43 min增加到13.18%，热相从61.00 min增加到84.20 min。通过一方面降低导热系数和渗透系数，另一方面增加热阻尼和相移，保留了特征生态混凝土应该有助于限制热损失，节能和改善热舒适性。
{"title":"Thermal Characterization of an Eco Conce Based on Lateritic Gravel, Millet Pods and Cement","authors":"D. Armand, Doko K. Valery, Wade Doukago Yacoubou Soumanou, Michozounnou Bénoît, Vianou Antoine","doi":"10.3844/ajeassp.2021.398.408","DOIUrl":"https://doi.org/10.3844/ajeassp.2021.398.408","url":null,"abstract":"Corresponding Author: Djossou Ayihaou Armand Laboratory of Thermophysical Characterization of Materials and Energy Appropriation (Labo-CTMAE)-Polytechnic School of Abomey-Calavi (EPAC), 01 BP 2009 Cotonou (Benin) Email: ayihaou@yahoo.fr Abstract: To simultaneously meet the need of thermal confort and living environment protection, vegetable biomass valorisation in building sector is of particular importance. In this context, the main objective of this study is to produce a lightweight composite concrete based on millet pods and lateritic gravel with a cement matrix for use in buildings to help improve thermal comfort and protect environment. To achieve this, the composite formulation with 250 kg.m cement dosage and an 0.8 water to cement ratio was used to manufacture two type test specimens of (4 4 16) cm dimensions for porosity tests and (4 4 5) cm for thermal tests with a millet pod rate varying from 0 to 6% with a step of 2%. Average thermophysical characteristics of 5 tests carriesd out over 5 days, namely: Thermal conductivity, thermal diffusivity, thermal effusivity, thermal phase and damping, were experimentally measured using fluxmetric method similar to that of mini hot plate method with two Peltier elements as fluxmeters. Results obtained showed that for 0, 2, 4 and 6% millet pods dosage, thermal conductivity values obtained are respectively 1.18 W.m.K, 0.74 W.m.K, 0.63 W.m.K and 0.61 W.m.K, i.e., a reduction of 93.44%. For same millet pod dosage, thermal effusivity values are 2157.33 J.m.K.s, 1236.34 J.m.K.s, 946.03 J.m.K.s and 775.04 J.m.K.s, i.e., a reduction of 64.07%. On the other hand, it was observed 3.00.10 m.s, 3.56.10 m.s, 4.47.10 m.s and 6.25.10 m.s, i.e., an increase of 108.33% for thermal diffusivity. With regard to dynamiquc thermal characteristics, it was obtained an increase from 5.43 to 13.18% for thermal damping and, from 61.00 to 84.20 min for thermal phase. Through on the one hand, thermal conductivity and effusivity decrease and on the other hand, thermal damping and phase shift increase, it is retained that characterized eco-concrete should contribute to thermal losses limitation, energiy saving and improved thermal comfort.","PeriodicalId":7425,"journal":{"name":"American Journal of Engineering and Applied Sciences","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85700504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-01DOI: 10.3844/ajeassp.2020.748.758
R. Khosravi, R. Fatahi, H. Siavoshi, F. Molaei
Using a software-based experiment design, the application of the leaching process for the extraction of manganese from Zinc Plant Slag (ZPS) was investigated. In this study, the effect of different parameters, i.e., H2SO4 concentration, pulp density, agitation rate, temperature and reaction time, was investigated. Response Surface Methodology (RSM) based on the Central Composite Design (CCD) has been implemented to consider the main parameters. A hydrometallurgical route to manganese silicate from spent zinc plant residue has been proposed in this investigation. Based on the investigation, Mn can be extracted from ZPS in sulfuric acid without any oxidant agents. The results showed that the optimum conditions of this study are an H2SO4 concentration of 2 mol/L and a solid/liquid ratio of 0.07 g/mL at 50°C for 150 min and an agitation speed of 1000 rpm. A manganese leaching efficiency higher than 83% is reached under these conditions, with a corresponding 22% iron, 23% lead, 68% zinc and 65% aluminum.
{"title":"Recovery of Manganese from Zinc Smelter Slag","authors":"R. Khosravi, R. Fatahi, H. Siavoshi, F. Molaei","doi":"10.3844/ajeassp.2020.748.758","DOIUrl":"https://doi.org/10.3844/ajeassp.2020.748.758","url":null,"abstract":"Using a software-based experiment design, the application of the leaching process for the extraction of manganese from Zinc Plant Slag (ZPS) was investigated. In this study, the effect of different parameters, i.e., H2SO4 concentration, pulp density, agitation rate, temperature and reaction time, was investigated. Response Surface Methodology (RSM) based on the Central Composite Design (CCD) has been implemented to consider the main parameters. A hydrometallurgical route to manganese silicate from spent zinc plant residue has been proposed in this investigation. Based on the investigation, Mn can be extracted from ZPS in sulfuric acid without any oxidant agents. The results showed that the optimum conditions of this study are an H2SO4 concentration of 2 mol/L and a solid/liquid ratio of 0.07 g/mL at 50°C for 150 min and an agitation speed of 1000 rpm. A manganese leaching efficiency higher than 83% is reached under these conditions, with a corresponding 22% iron, 23% lead, 68% zinc and 65% aluminum.","PeriodicalId":7425,"journal":{"name":"American Journal of Engineering and Applied Sciences","volume":"61 1","pages":"748-758"},"PeriodicalIF":0.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79695678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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