Pub Date : 2024-01-01DOI: 10.22581/muet1982.2401.2756
Anqa Min Allah, Jamshaid Iqbal, Shahid Amjad
Pakistan is facing chronic energy crises since many years. This paper aims to provide an overview of the current status of energy efficiency and conservation practices at organizational level in Pakistan. The first phase of this study evaluates the trends in electricity consumption in selected buildings over the last six years (2017–2022). Subsequently, a survey was conducted in selected buildings to assess employee morale and knowledge of energy efficiency and conservation. Results show an insignificant change in electricity consumption in selected buildings during the past six year’s period indicating a poor culture of energy savings in the selected organization. Despite a constant electricity consumption from 2017 to 2022, a significant fluctuation in average billing amounts was observed. This is possibly due to electricity tariff that has continuously been fluctuating since last few years in Pakistan including Karachi. Study reveals that more than 50% of the employees in selected organization were aware about the importance of energy efficiency and conservation however, they rarely practice the energy saving measures during their routine activities. This is perhaps due to the lack of sense of national stewardship among the employees. It was also found that most of the employees of the selected organization are aware and motivated towards the environmental and climate change concerns related to energy production and its efficient use. However, again a small number of employees were found practicing the energy conservation and efficiency measures. According to this study, companies should encourage staff members to save energy by offering frequent trainings and educational opportunities. Additionally, the organizations ought to think about switching to renewable energy sources.
{"title":"Organizational level energy conservation and efficiency - a case of public sector organization in Karachi, Pakistan","authors":"Anqa Min Allah, Jamshaid Iqbal, Shahid Amjad","doi":"10.22581/muet1982.2401.2756","DOIUrl":"https://doi.org/10.22581/muet1982.2401.2756","url":null,"abstract":"Pakistan is facing chronic energy crises since many years. This paper aims to provide an overview of the current status of energy efficiency and conservation practices at organizational level in Pakistan. The first phase of this study evaluates the trends in electricity consumption in selected buildings over the last six years (2017–2022). Subsequently, a survey was conducted in selected buildings to assess employee morale and knowledge of energy efficiency and conservation. Results show an insignificant change in electricity consumption in selected buildings during the past six year’s period indicating a poor culture of energy savings in the selected organization. Despite a constant electricity consumption from 2017 to 2022, a significant fluctuation in average billing amounts was observed. This is possibly due to electricity tariff that has continuously been fluctuating since last few years in Pakistan including Karachi. Study reveals that more than 50% of the employees in selected organization were aware about the importance of energy efficiency and conservation however, they rarely practice the energy saving measures during their routine activities. This is perhaps due to the lack of sense of national stewardship among the employees. It was also found that most of the employees of the selected organization are aware and motivated towards the environmental and climate change concerns related to energy production and its efficient use. However, again a small number of employees were found practicing the energy conservation and efficiency measures. According to this study, companies should encourage staff members to save energy by offering frequent trainings and educational opportunities. Additionally, the organizations ought to think about switching to renewable energy sources.","PeriodicalId":44836,"journal":{"name":"Mehran University Research Journal of Engineering and Technology","volume":"39 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139127644","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 : 2024-01-01DOI: 10.22581/muet1982.2401.2969
Abdullah Abdullah, Shahid Mehmood, Rana Atta Ur Rahman
This paper explores the optimization of Tungsten-Inert-Gas (TIG) welding process parameters for creating a hybrid structure of Aluminium 6061 and Stainless Steel 304 using a copper filler rod (ER-Cu). The Welding of these two materials has industrial relevance owing to its weight reduction capabilities and environmental benefits. However, Aluminium and Stainless-Steel have different melting points and thermal properties. Aluminium has twice coefficient of thermal expansion and six times coefficient of thermal conductance as compared to Stainless-Steel. This difference often results in residual stresses and brittle intermetallic compounds in the weld region. We have chosen the Welding Current, Welding Speed, and Gas Flow Rate as input parameters, and Ultimate Tensile Strength (UTS) and Micro-hardness as response parameters. We have employed the Response Surface Methodology (RSM) using a Box-Behnken design to evaluate the influence of input parameters on UTS and Micro-hardness. Furthermore, an Analysis of Variance (ANOVA) is conducted to determine the input parameters' significance on the response parameters. Our surface plots demonstrate that UTS improves with increased Welding Current and reduced Welding Speed. Simultaneously, Micro-hardness increases with elevated Welding Speed and decreased current, up to a specific limit. The peak value of UTS (79 MPa) was observed with a Current range of 85-90 A, Speed range of 95-100 mm/min, and Gas Flow Rate of 14.5-15 l/min. On the other hand, maximum Micro-hardness (260HV) was obtained with a Current range of 80-85 A, Speed range of 105-110 mm/min, and Gas Flow Rate of 14.5-15 l/min. This research contributes to improving the manufacturing process of hybrid structures, specifically by optimizing the advantages of both Aluminium and Stainless Steel while addressing the challenges that arise during their combination. The study's conclusions have major consequences for sectors looking to take advantage on the mutually beneficial characteristics of different metals in welding applications.
{"title":"Investigating parametric effects during TIG welding of dissimilar metals","authors":"Abdullah Abdullah, Shahid Mehmood, Rana Atta Ur Rahman","doi":"10.22581/muet1982.2401.2969","DOIUrl":"https://doi.org/10.22581/muet1982.2401.2969","url":null,"abstract":"This paper explores the optimization of Tungsten-Inert-Gas (TIG) welding process parameters for creating a hybrid structure of Aluminium 6061 and Stainless Steel 304 using a copper filler rod (ER-Cu). The Welding of these two materials has industrial relevance owing to its weight reduction capabilities and environmental benefits. However, Aluminium and Stainless-Steel have different melting points and thermal properties. Aluminium has twice coefficient of thermal expansion and six times coefficient of thermal conductance as compared to Stainless-Steel. This difference often results in residual stresses and brittle intermetallic compounds in the weld region. We have chosen the Welding Current, Welding Speed, and Gas Flow Rate as input parameters, and Ultimate Tensile Strength (UTS) and Micro-hardness as response parameters. We have employed the Response Surface Methodology (RSM) using a Box-Behnken design to evaluate the influence of input parameters on UTS and Micro-hardness. Furthermore, an Analysis of Variance (ANOVA) is conducted to determine the input parameters' significance on the response parameters. Our surface plots demonstrate that UTS improves with increased Welding Current and reduced Welding Speed. Simultaneously, Micro-hardness increases with elevated Welding Speed and decreased current, up to a specific limit. The peak value of UTS (79 MPa) was observed with a Current range of 85-90 A, Speed range of 95-100 mm/min, and Gas Flow Rate of 14.5-15 l/min. On the other hand, maximum Micro-hardness (260HV) was obtained with a Current range of 80-85 A, Speed range of 105-110 mm/min, and Gas Flow Rate of 14.5-15 l/min. This research contributes to improving the manufacturing process of hybrid structures, specifically by optimizing the advantages of both Aluminium and Stainless Steel while addressing the challenges that arise during their combination. The study's conclusions have major consequences for sectors looking to take advantage on the mutually beneficial characteristics of different metals in welding applications.","PeriodicalId":44836,"journal":{"name":"Mehran University Research Journal of Engineering and Technology","volume":"70 8","pages":""},"PeriodicalIF":0.6,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139128223","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 : 2024-01-01DOI: 10.22581/muet1982.2401.2910
Muhammad Awais, Feroz Ahmed Soomro, Shreen El-Sapa, Rahim Bux Khokhar
Heat transfer occurs as a result of density differences caused by temperature changes. It has several industrial applications. To improve performance, one must investigate the heat transfer behaviour of the working fluid. Hence, the purpose of this work is to report a heat transfer analysis of a partially heated trapezoid cavity filled with a hybrid nanofluid. The temperature conditions of the cavity are such that the bottom boundary is partially heated, inclined side boundaries are kept at a lower temperature, and the upper boundary is kept adiabatic. A trapezoidal shape heated obstacle is considered in the cavity’s centre. The heat transfer and flow take place inside the cavity due to density variation. The mechanism is regulated by mass, momentum, and energy conservation, as well as related boundary constraints. The solutions are determined by the use of a numerical technique known as the Finite Element Method after the governing equations are transformed into non-dimensional form, which brings up physical parameters affecting the heat transfer and flow. The initial study is performed for three types of nanofluids with silver 𝐴𝑔 and magnesium oxide 𝑀𝑔𝑜 nanoparticles inside water 𝐻2𝑂, kerosene 𝐾𝑒, and engine oil 𝐸𝑂. The study revealed that the engine oil-based hybrid nanofluid produced an increased heat transfer rate. Simulation is performed using engine-based hybrid nanofluid with the range of physical parameters, such as Rayleigh number 𝑅𝑎 (105≤𝑅𝑎≤107), Hartmann number 𝐻𝑎 (0≤𝐻𝑎≤100) and nanoparticles volume fraction 𝜙 (0≤𝜙≤0.2). It is found that the heat transfer rate is enhanced by increasing the fraction of nanoparticles in the base fluid. Moreover, imposition of magnetic field has reverse impact on the fluid movement.
{"title":"Heat transfer augmentation through engine oil-based hybrid nanofluid inside a trapezoid cavity","authors":"Muhammad Awais, Feroz Ahmed Soomro, Shreen El-Sapa, Rahim Bux Khokhar","doi":"10.22581/muet1982.2401.2910","DOIUrl":"https://doi.org/10.22581/muet1982.2401.2910","url":null,"abstract":"Heat transfer occurs as a result of density differences caused by temperature changes. It has several industrial applications. To improve performance, one must investigate the heat transfer behaviour of the working fluid. Hence, the purpose of this work is to report a heat transfer analysis of a partially heated trapezoid cavity filled with a hybrid nanofluid. The temperature conditions of the cavity are such that the bottom boundary is partially heated, inclined side boundaries are kept at a lower temperature, and the upper boundary is kept adiabatic. A trapezoidal shape heated obstacle is considered in the cavity’s centre. The heat transfer and flow take place inside the cavity due to density variation. The mechanism is regulated by mass, momentum, and energy conservation, as well as related boundary constraints. The solutions are determined by the use of a numerical technique known as the Finite Element Method after the governing equations are transformed into non-dimensional form, which brings up physical parameters affecting the heat transfer and flow. The initial study is performed for three types of nanofluids with silver 𝐴𝑔 and magnesium oxide 𝑀𝑔𝑜 nanoparticles inside water 𝐻2𝑂, kerosene 𝐾𝑒, and engine oil 𝐸𝑂. The study revealed that the engine oil-based hybrid nanofluid produced an increased heat transfer rate. Simulation is performed using engine-based hybrid nanofluid with the range of physical parameters, such as Rayleigh number 𝑅𝑎 (105≤𝑅𝑎≤107), Hartmann number 𝐻𝑎 (0≤𝐻𝑎≤100) and nanoparticles volume fraction 𝜙 (0≤𝜙≤0.2). It is found that the heat transfer rate is enhanced by increasing the fraction of nanoparticles in the base fluid. Moreover, imposition of magnetic field has reverse impact on the fluid movement.","PeriodicalId":44836,"journal":{"name":"Mehran University Research Journal of Engineering and Technology","volume":"80 15","pages":""},"PeriodicalIF":0.6,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139125050","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}
Computer networks have become the backbone of our interconnected world in today's technologically driven landscape. Unauthorized access or malicious activity carried out by threat actors to acquire control of network resources, exploit vulnerabilities, or undermine system integrity are examples of network intrusion. ZSL(Zero-Shot Learning) is a machine learning paradigm that addresses the problem of detecting and categorizing objects or concepts that were not present in the training data. . Traditional supervised learning algorithms for intrusion detection frequently struggle with insufficient labeled data and may struggle to adapt to unexpected assault patterns. In this article We have proposed a unique zero-shot learning hybrid partial label model suited to a large image-based network intrusion dataset to overcome these difficulties. The core contribution of this study is the creation and successful implementation of a novel zero-shot learning hybrid partial label model for network intrusion detection, which has a remarkable accuracy of 99.12%. The suggested system lays the groundwork for future study into other feature selection techniques and the performance of other machine learning classifiers on larger datasets. Such research can advance the state-of-the-art in intrusion detection and improve our ability to detect and prevent the network attacks. We hope that our research will spur additional research and innovation in this critical area of cybersecurity.
{"title":"A novel approach to intrusion detection using zero-shot learning hybrid partial labels","authors":"Syed Atir Raza, Mehwish Shaikh, Raybal Akhtar, Aqsa Anwar","doi":"10.22581/muet1982.2401.2945","DOIUrl":"https://doi.org/10.22581/muet1982.2401.2945","url":null,"abstract":"Computer networks have become the backbone of our interconnected world in today's technologically driven landscape. Unauthorized access or malicious activity carried out by threat actors to acquire control of network resources, exploit vulnerabilities, or undermine system integrity are examples of network intrusion. ZSL(Zero-Shot Learning) is a machine learning paradigm that addresses the problem of detecting and categorizing objects or concepts that were not present in the training data. . Traditional supervised learning algorithms for intrusion detection frequently struggle with insufficient labeled data and may struggle to adapt to unexpected assault patterns. In this article We have proposed a unique zero-shot learning hybrid partial label model suited to a large image-based network intrusion dataset to overcome these difficulties. The core contribution of this study is the creation and successful implementation of a novel zero-shot learning hybrid partial label model for network intrusion detection, which has a remarkable accuracy of 99.12%. The suggested system lays the groundwork for future study into other feature selection techniques and the performance of other machine learning classifiers on larger datasets. Such research can advance the state-of-the-art in intrusion detection and improve our ability to detect and prevent the network attacks. We hope that our research will spur additional research and innovation in this critical area of cybersecurity.","PeriodicalId":44836,"journal":{"name":"Mehran University Research Journal of Engineering and Technology","volume":"19 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139128193","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 : 2024-01-01DOI: 10.22581/muet1982.2401.3009
Muhammad Awais, Tayyab Naveed, Fiaz Hussain, S. Malik, Assad Farooq, S. Krzywinski
Human thermal comfort within various environmental conditions is of paramount importance in a wide range of industries, including clothing design, indoor climate control, and occupational safety. Researchers are always in search the sophisticated tools and techniques that simulate the thermal regulation of human body under different environmental conditions. The present research aims to present a precise methodology for the simulation of clothed thermal manikin in controlled environmental conditions. A comprehensive method is recommended that consists of the use of 3D body scanning technology, different 2D and 3D CAD as well as thermal simulation software. The results of the simulations are very satisfactory, which are later validated with the wear trials with the help of the same clothed thermal manikin and under the same environmental conditions. The comparative analysis shows some deviations that are discussed thoroughly and the need for further research is highlighted in the papers as well. Furthermore, the present research gives us a digital platform to understand the clothing's thermal comfort and the parameters that affect it with the consideration of the draping behavior of the clothing, microclimate, thermal properties, and surrounding environmental conditions.
{"title":"Simulation-based thermal analysis and validation of clothed thermal manikin","authors":"Muhammad Awais, Tayyab Naveed, Fiaz Hussain, S. Malik, Assad Farooq, S. Krzywinski","doi":"10.22581/muet1982.2401.3009","DOIUrl":"https://doi.org/10.22581/muet1982.2401.3009","url":null,"abstract":"Human thermal comfort within various environmental conditions is of paramount importance in a wide range of industries, including clothing design, indoor climate control, and occupational safety. Researchers are always in search the sophisticated tools and techniques that simulate the thermal regulation of human body under different environmental conditions. The present research aims to present a precise methodology for the simulation of clothed thermal manikin in controlled environmental conditions. A comprehensive method is recommended that consists of the use of 3D body scanning technology, different 2D and 3D CAD as well as thermal simulation software. The results of the simulations are very satisfactory, which are later validated with the wear trials with the help of the same clothed thermal manikin and under the same environmental conditions. The comparative analysis shows some deviations that are discussed thoroughly and the need for further research is highlighted in the papers as well. Furthermore, the present research gives us a digital platform to understand the clothing's thermal comfort and the parameters that affect it with the consideration of the draping behavior of the clothing, microclimate, thermal properties, and surrounding environmental conditions.","PeriodicalId":44836,"journal":{"name":"Mehran University Research Journal of Engineering and Technology","volume":"22 12","pages":""},"PeriodicalIF":0.6,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139129840","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 : 2024-01-01DOI: 10.22581/muet1982.2401.2877
Rabia Almas, Nadir Ali Rind, Abdul khaliq Jhatial
The synthetic dyes used in textile industry cause severe health and environmental problems. Since production of these colors includes a noteworthy quantity of energy, water, and poisonous chemicals. Therefore, natural dyes from waste provide a significant source of study for the extraction of pigments. To use these natural dyes to its full extent, researchers used mordants to change the hue of the same natural dye and to get a range of shades from same source. Nonetheless, these mordants are toxic in nature. Therefore, to address this issue, in the present study, sustainable and environment friendly natural ingredients are studied to change the hue of the natural cutch dye. The results revealed that these natural ingredients can successfully developed new shades from the same natural dye without any negative effect on the fastness properties of the dyed cotton fabric.
{"title":"Sustainable natural dyeing of cellulose with agricultural medicinal plant waste, new shades development with nontoxic sustainable elements","authors":"Rabia Almas, Nadir Ali Rind, Abdul khaliq Jhatial","doi":"10.22581/muet1982.2401.2877","DOIUrl":"https://doi.org/10.22581/muet1982.2401.2877","url":null,"abstract":"The synthetic dyes used in textile industry cause severe health and environmental problems. Since production of these colors includes a noteworthy quantity of energy, water, and poisonous chemicals. Therefore, natural dyes from waste provide a significant source of study for the extraction of pigments. To use these natural dyes to its full extent, researchers used mordants to change the hue of the same natural dye and to get a range of shades from same source. Nonetheless, these mordants are toxic in nature. Therefore, to address this issue, in the present study, sustainable and environment friendly natural ingredients are studied to change the hue of the natural cutch dye. The results revealed that these natural ingredients can successfully developed new shades from the same natural dye without any negative effect on the fastness properties of the dyed cotton fabric.","PeriodicalId":44836,"journal":{"name":"Mehran University Research Journal of Engineering and Technology","volume":"49 26","pages":""},"PeriodicalIF":0.6,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139125487","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 : 2024-01-01DOI: 10.22581/muet1982.2401.2938
Khurram Shahzad Baig, Fazeel Ahmad, Usman Asghar, Waqas Ahmed Khan
Previously, activated carbon was used as adsorbent for the removal of heavy metals at batch scale and the reported removal efficiency was up to 25 % (while in our technique the efficiency is up to 75%). The large industries operate with continuous processes and discharge large amount of wastewater containing heavy metals. No research was published for continuous operation using fluidized bed adsorption column till now. The novelty of this study is on the mode of operation (continuous operation at large scale under fixed and fluidized bed conditions), Biosorbent activated carbon (AC), and maximum efficiency of arsenic removal (i.e. 75 %). The Biosorbent activated carbon prepared from waste agriculture material. Industrial wastewater consists of many inorganic and organic pollutants which are discharged into water bodies resulting the serious health problems. Now a days, concentration of arsenic has much increased as compared to the permissive concentration level (25mg/L). Therefore, there is need to reduce this concentration up to threshold value (10μg/L). The use of biosorbents for arsenic removal from wastewater has global significance due to its widespread availability and low cost. Biosorption of Arsenic strongly depends on the initial metal concentration, contact time, speed of stirring, pH and temperature. The maximum arsenic as (III) removed at pH-7.5 is 70%, it was improved to 83% by agitation in batch experiments. While in continuous mode experiments (Fixed bed) the bed height and flow rates were varied. At the Fluidized bed experiments, the maximum As (III) removed was 75%. The effects of several factors such as pH, initial solute concentration, biosorbents dose, has been revaluated in this paper. The low cost, easily available biosorbent AC is recommended for removal of arsenic from contaminated wastewaters to bring them in compliance.
{"title":"Biosorption studies on arsenic (III) removal from industrial wastewater by using fixed and fluidized bed operation","authors":"Khurram Shahzad Baig, Fazeel Ahmad, Usman Asghar, Waqas Ahmed Khan","doi":"10.22581/muet1982.2401.2938","DOIUrl":"https://doi.org/10.22581/muet1982.2401.2938","url":null,"abstract":"Previously, activated carbon was used as adsorbent for the removal of heavy metals at batch scale and the reported removal efficiency was up to 25 % (while in our technique the efficiency is up to 75%). The large industries operate with continuous processes and discharge large amount of wastewater containing heavy metals. No research was published for continuous operation using fluidized bed adsorption column till now. The novelty of this study is on the mode of operation (continuous operation at large scale under fixed and fluidized bed conditions), Biosorbent activated carbon (AC), and maximum efficiency of arsenic removal (i.e. 75 %). The Biosorbent activated carbon prepared from waste agriculture material. Industrial wastewater consists of many inorganic and organic pollutants which are discharged into water bodies resulting the serious health problems. Now a days, concentration of arsenic has much increased as compared to the permissive concentration level (25mg/L). Therefore, there is need to reduce this concentration up to threshold value (10μg/L). The use of biosorbents for arsenic removal from wastewater has global significance due to its widespread availability and low cost. Biosorption of Arsenic strongly depends on the initial metal concentration, contact time, speed of stirring, pH and temperature. The maximum arsenic as (III) removed at pH-7.5 is 70%, it was improved to 83% by agitation in batch experiments. While in continuous mode experiments (Fixed bed) the bed height and flow rates were varied. At the Fluidized bed experiments, the maximum As (III) removed was 75%. The effects of several factors such as pH, initial solute concentration, biosorbents dose, has been revaluated in this paper. The low cost, easily available biosorbent AC is recommended for removal of arsenic from contaminated wastewaters to bring them in compliance.","PeriodicalId":44836,"journal":{"name":"Mehran University Research Journal of Engineering and Technology","volume":"69 13","pages":""},"PeriodicalIF":0.6,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139127253","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 : 2024-01-01DOI: 10.22581/muet1982.2401.2679
Asif Durez, Muhammad Umer Sohail, Muzaffar Ali, Umer Azeem Khan
Passive cooling of photovoltaics (PV) using phase change materials (PCM) may be extremely effective owing to their enormous implicit specific heat. However, the low rate of heat transfer, high solar radiation, and ambient temperature drop its efficiency by 0.45%/ᵒC. Only such a small fraction of solar irradiance is turned into electrical energy by PV cells; most of the irradiation is transformed into heat; hence, cells start operating above ambient temperature. Therefore, the exterior heat of photovoltaic panels is controlled by applying artificial cooling to enhance their efficiency. The current research aims on the significant benefits of using PCM to reduce panel surface temperature in terms of boosting energy efficiency and maintaining thermal comfort. This study demonstrates a successful design of PV controlled-temperature module using phase change materials for hot climate, especially for south Asian regions. The surface temperature of solar panels has been reduced using computational analysis and experimental study on paraffin wax. In this work, Paraffin wax used, which reduced the panel surface temperature by 5-7ᵒC, generating a 29% increase of the modified PV panel relative efficiency compared to its standard value.
{"title":"Thermal analysis and efficiency enhancement of solar modified PV panels through organic PCM under climate conditions of Pakistan","authors":"Asif Durez, Muhammad Umer Sohail, Muzaffar Ali, Umer Azeem Khan","doi":"10.22581/muet1982.2401.2679","DOIUrl":"https://doi.org/10.22581/muet1982.2401.2679","url":null,"abstract":"Passive cooling of photovoltaics (PV) using phase change materials (PCM) may be extremely effective owing to their enormous implicit specific heat. However, the low rate of heat transfer, high solar radiation, and ambient temperature drop its efficiency by 0.45%/ᵒC. Only such a small fraction of solar irradiance is turned into electrical energy by PV cells; most of the irradiation is transformed into heat; hence, cells start operating above ambient temperature. Therefore, the exterior heat of photovoltaic panels is controlled by applying artificial cooling to enhance their efficiency. The current research aims on the significant benefits of using PCM to reduce panel surface temperature in terms of boosting energy efficiency and maintaining thermal comfort. This study demonstrates a successful design of PV controlled-temperature module using phase change materials for hot climate, especially for south Asian regions. The surface temperature of solar panels has been reduced using computational analysis and experimental study on paraffin wax. In this work, Paraffin wax used, which reduced the panel surface temperature by 5-7ᵒC, generating a 29% increase of the modified PV panel relative efficiency compared to its standard value.","PeriodicalId":44836,"journal":{"name":"Mehran University Research Journal of Engineering and Technology","volume":"79 12","pages":""},"PeriodicalIF":0.6,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139128130","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}
This research investigates the influence of incorporating small-diameter polypropylene fibers on the mechanical properties of concrete. The studied concrete properties include compressive strength, tensile strength, flexural strength (both plain and reinforced), shear strength, and the mitigation of shrinkage cracks. A total of 92 specimens were meticulously fabricated in the laboratory, comprising cylinders (12 inches in length and 6 inches in diameter), beams (20 x 4 x 4 inches), larger beams (60 x 9 x 9 inches), and slab panels (48 x 48 x 4 inches). During the specimen casting process, a consistent mix with a ratio of 1:2:4 and a water-cement ratio of 0.60 was consistently applied. The polypropylene fiber content varied at 0%, 0.2%, 0.4%, and 0.6% for each property examination. Results indicate a positive impact on all concrete properties studied upon the addition of polypropylene fibers. However, the optimal percentage of polypropylene fibers exhibited variability for each variable and property under investigation. This research contributes insights into the nuanced effects of polypropylene fibers on concrete properties, providing a basis for further exploration and practical application in optimizing concrete performance and durability.
本研究探讨了加入小直径聚丙烯纤维对混凝土机械性能的影响。所研究的混凝土性能包括抗压强度、抗拉强度、抗弯强度（普通强度和增强强度）、抗剪强度以及收缩裂缝的缓解。实验室共精心制作了 92 个试样，包括圆柱体（长 12 英寸，直径 6 英寸）、梁（20 x 4 x 4 英寸）、较大的梁（60 x 9 x 9 英寸）和板块（48 x 48 x 4 英寸）。在浇注试样的过程中，始终使用比例为 1:2:4 和水灰比为 0.60 的混合料。在每次性能检测中，聚丙烯纤维的含量分别为 0%、0.2%、0.4% 和 0.6%。结果表明，添加聚丙烯纤维对所研究的所有混凝土性能都有积极影响。然而，聚丙烯纤维的最佳比例对于每个变量和所研究的性能来说都存在差异。这项研究有助于深入了解聚丙烯纤维对混凝土性能的细微影响，为进一步探索和实际应用优化混凝土性能和耐久性奠定了基础。
{"title":"Evaluation of strength parameters of plain and reinforced concrete with the addition of polypropylene fibers","authors":"A. Ajwad, Usman Ilyas, Lutufullah Muzammal, Azhan Umer, Syed Muneeb Haider","doi":"10.22581/muet1982.2401.2735","DOIUrl":"https://doi.org/10.22581/muet1982.2401.2735","url":null,"abstract":"This research investigates the influence of incorporating small-diameter polypropylene fibers on the mechanical properties of concrete. The studied concrete properties include compressive strength, tensile strength, flexural strength (both plain and reinforced), shear strength, and the mitigation of shrinkage cracks. A total of 92 specimens were meticulously fabricated in the laboratory, comprising cylinders (12 inches in length and 6 inches in diameter), beams (20 x 4 x 4 inches), larger beams (60 x 9 x 9 inches), and slab panels (48 x 48 x 4 inches). During the specimen casting process, a consistent mix with a ratio of 1:2:4 and a water-cement ratio of 0.60 was consistently applied. The polypropylene fiber content varied at 0%, 0.2%, 0.4%, and 0.6% for each property examination. Results indicate a positive impact on all concrete properties studied upon the addition of polypropylene fibers. However, the optimal percentage of polypropylene fibers exhibited variability for each variable and property under investigation. This research contributes insights into the nuanced effects of polypropylene fibers on concrete properties, providing a basis for further exploration and practical application in optimizing concrete performance and durability.","PeriodicalId":44836,"journal":{"name":"Mehran University Research Journal of Engineering and Technology","volume":"33 4","pages":""},"PeriodicalIF":0.6,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139129502","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 : 2023-10-05DOI: 10.22581/muet1982.2304.2906
Rafaqat Hussain Arain, Riaz Ahmed Shaikh, Safdar Ali Shah, Sajjad Ali Shah, Saima Rafique, Ahmed Masood Ansari
In order to protect the web against automated attacks, CAPTCHAs are most widely used mechanism on the internet. Numerous types of CAPTCHAs are introduced due to weaknesses in the earlier designs. Animated CAPTCHAs are one of the design alternatives. Instead of presenting the whole information at once, animated CAPTCHAs present information in various frames over the specific interval of time. As CATPCHAs are ubiquitously used to avoid the serious threats from bots therefore it is important to verify their effectiveness. In this research we have verified their robustness against machine learning attacks. It has been proved that adding the extra time dimension does not necessarily ensure protection against automated attacks. We have attacked the Hello CAPTCHA scheme, which is the most popular animated CAPTCHA scheme available on the internet. By applying novel image processing and machine learning techniques, these CAPTCHAs are decoded with high precision. A pre-trained CNN is used to recognize the extracted characters. In this research, 6 popular types of animated CAPTCHAs along with 41 sub types were successfully deciphered with an overall precision of up to 99.5 %.
{"title":"Decoding the animated text-based captchas to verify their robustness against automated attacks","authors":"Rafaqat Hussain Arain, Riaz Ahmed Shaikh, Safdar Ali Shah, Sajjad Ali Shah, Saima Rafique, Ahmed Masood Ansari","doi":"10.22581/muet1982.2304.2906","DOIUrl":"https://doi.org/10.22581/muet1982.2304.2906","url":null,"abstract":"In order to protect the web against automated attacks, CAPTCHAs are most widely used mechanism on the internet. Numerous types of CAPTCHAs are introduced due to weaknesses in the earlier designs. Animated CAPTCHAs are one of the design alternatives. Instead of presenting the whole information at once, animated CAPTCHAs present information in various frames over the specific interval of time. As CATPCHAs are ubiquitously used to avoid the serious threats from bots therefore it is important to verify their effectiveness. In this research we have verified their robustness against machine learning attacks. It has been proved that adding the extra time dimension does not necessarily ensure protection against automated attacks. We have attacked the Hello CAPTCHA scheme, which is the most popular animated CAPTCHA scheme available on the internet. By applying novel image processing and machine learning techniques, these CAPTCHAs are decoded with high precision. A pre-trained CNN is used to recognize the extracted characters. In this research, 6 popular types of animated CAPTCHAs along with 41 sub types were successfully deciphered with an overall precision of up to 99.5 %.","PeriodicalId":44836,"journal":{"name":"Mehran University Research Journal of Engineering and Technology","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135483419","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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