Building project implementation has so many issues and complex performance, such as time, cost, quality, and safety. This study identified and assessed the essential factors influencing the implementation of public building projects, particularly in the Bole Sub-city of Addis Ababa. There were 46 factors identified, validated, and divided into 9 categories. Questionnaires are distributed to 120 respondents, of which 8 for owners, 25 for consultants, 86 for contractors, and one head of the office. The key factors decided upon were: liquidity of the organization, improved availability of commodity prices for people with high experience and expertise, and the quality of equipment and raw materials in the project. The agreement between the parties on the ranking of factors was calculated based on their Relative Importance Index. Besides, the value of the Cronbach’s Alpha for variables calculated above 0.7, which means the data and scale are reliable and accepted for further analysis to correlate the different groups of factors. Results showed that cost, time, quality, productivity, and customer satisfaction are the top five essential factors affecting the performance of the government public building in the study area.
{"title":"Factors Affecting the Performance in the Implementation of Government Building Construction Projects: A Case Study in Bole Sub- City of Addis Ababa","authors":"Serkalem Molla, E. Quezon, Eyob Mekonnen, Woyesa Ararsa, Dumesa Gudissa, Anteneh Tibebu","doi":"10.37896/jxu14.11/020","DOIUrl":"https://doi.org/10.37896/jxu14.11/020","url":null,"abstract":"Building project implementation has so many issues and complex performance, such as time, cost, quality, and safety. This study identified and assessed the essential factors influencing the implementation of public building projects, particularly in the Bole Sub-city of Addis Ababa. There were 46 factors identified, validated, and divided into 9 categories. Questionnaires are distributed to 120 respondents, of which 8 for owners, 25 for consultants, 86 for contractors, and one head of the office. The key factors decided upon were: liquidity of the organization, improved availability of commodity prices for people with high experience and expertise, and the quality of equipment and raw materials in the project. The agreement between the parties on the ranking of factors was calculated based on their Relative Importance Index. Besides, the value of the Cronbach’s Alpha for variables calculated above 0.7, which means the data and scale are reliable and accepted for further analysis to correlate the different groups of factors. Results showed that cost, time, quality, productivity, and customer satisfaction are the top five essential factors affecting the performance of the government public building in the study area.","PeriodicalId":10639,"journal":{"name":"Computational Materials Science eJournal","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79226788","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}
The interaction of cutting tool and workpiece in the contact zone is crucial with regard to tool wear. This is of particular relevance for difficult to machine materials such as titanium Ti6Al4V in continuous operations like turning. Due to the low thermal conductivity of titanium, the heat generated during cutting mainly flows into the tool leading to high tool temperatures. In addition, the low Young’s modulus in combination with the high yield strength of Ti6Al4V leads to high normal and shear stresses acting on the tool surfaces and to detrimental ploughing unless sharp cutting edges are used. Previous attempts to increase the tool life in turning of Ti6Al4V by coatings have not been satisfactory. Temperature active coatings are expected to reduce friction and thus tool wear, allowing for more productive cutting conditions or reduced use of coolant. Tribological conditions strongly differ between rake and clearance face in terms of sliding velocity, stress state and temperature, while insights into the contact zone during cutting are difficult to obtain. Thus, for preliminary assessment of the tool performance, tribological pin-on-disc tests are generally used. However, they suffer from the drawback of a closed friction system, as the pin repeatedly engages the same track on the material specimen, thereby affecting its tribological behavior. In order to suitably emulate mechanical and thermal conditions in continuous cutting, an open friction system has been designed, which is characterized by simultaneous adjustment and measurement of acting forces. At the same time, tool surface temperatures are captured by intermittent radiation measurement. Consequently, the open friction test rig enables the separate investigation of the tribological conditions of rake and clearance face. In this paper, the test rig design and first experimental results obtained from tribological investigations are reported. Separation of forces and subsequent evaluation of stresses acting on both tool surfaces is explained.
{"title":"Development of a Process-Oriented Tribological Test Rig for the Performance Assessment of Tool Coatings in Turning of Titanium Ti6Al4V","authors":"W. Hintze, P. Ploog, Melchior Bluehm, C. Möller","doi":"10.2139/ssrn.3724119","DOIUrl":"https://doi.org/10.2139/ssrn.3724119","url":null,"abstract":"The interaction of cutting tool and workpiece in the contact zone is crucial with regard to tool wear. This is of particular relevance for difficult to machine materials such as titanium Ti6Al4V in continuous operations like turning. Due to the low thermal conductivity of titanium, the heat generated during cutting mainly flows into the tool leading to high tool temperatures. In addition, the low Young’s modulus in combination with the high yield strength of Ti6Al4V leads to high normal and shear stresses acting on the tool surfaces and to detrimental ploughing unless sharp cutting edges are used. Previous attempts to increase the tool life in turning of Ti6Al4V by coatings have not been satisfactory. \u0000 \u0000Temperature active coatings are expected to reduce friction and thus tool wear, allowing for more productive cutting conditions or reduced use of coolant. Tribological conditions strongly differ between rake and clearance face in terms of sliding velocity, stress state and temperature, while insights into the contact zone during cutting are difficult to obtain. Thus, for preliminary assessment of the tool performance, tribological pin-on-disc tests are generally used. However, they suffer from the drawback of a closed friction system, as the pin repeatedly engages the same track on the material specimen, thereby affecting its tribological behavior. In order to suitably emulate mechanical and thermal conditions in continuous cutting, an open friction system has been designed, which is characterized by simultaneous adjustment and measurement of acting forces. At the same time, tool surface temperatures are captured by intermittent radiation measurement. Consequently, the open friction test rig enables the separate investigation of the tribological conditions of rake and clearance face. \u0000 \u0000In this paper, the test rig design and first experimental results obtained from tribological investigations are reported. Separation of forces and subsequent evaluation of stresses acting on both tool surfaces is explained.","PeriodicalId":10639,"journal":{"name":"Computational Materials Science eJournal","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77984416","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 : 2020-10-31DOI: 10.15587/2706-5448.2020.212752
V. Buzovskyi, Mykhail Kologrivov, A. Antonova
The object of research is a data model that characterizes the pumping units of main oil pipelines. The paper considers the creation of pumps database and their characteristics as a component of software systems designed to search for sources of energy saving in pipeline transportation of oil and oil products.
An overview of existing programs for calculating the joint operation of an oil pumping station and a pipeline is given. It is shown that most programs are inaccessible for analyzing the applied data storage technologies, or involve manual input of entry data without using databases. Comparative analysis of spreadsheets and relational databases is performed. It is shown that relational databases better meet the requirements of data convenience, availability, scalability, and performance. A physical model of a relational database is presented. The parent and child entities have been established, which make it possible to fully reflect all information about the pumping unit, namely:
– coefficients of hydraulic characteristics depending on the diameter of the impeller rotor;
– characteristics depending only on the pump make;
– classification of the pump by design or purpose. Relationship types and referential integrity rules are defined between entities when deleting or updating data. For data management, the SQLite system is proposed, which provides data manipulation in the SQL query language and does not require the development of additional software. The analysis of possible ways of organizing multilingualism using a database is carried out. The text of the SQL query is proposed, which allows to select the pump with its characteristics by the pump make and impeller diameter. A database structure is proposed that allows storing information about equipment for oil pipelines for various purposes, which makes it possible for automated calculations of complex technological processes. The pumping unit database is an open source project that is posted on the public web service GitHub.
{"title":"Oil Storages and Main Oil Pipelines Pumps Database Development","authors":"V. Buzovskyi, Mykhail Kologrivov, A. Antonova","doi":"10.15587/2706-5448.2020.212752","DOIUrl":"https://doi.org/10.15587/2706-5448.2020.212752","url":null,"abstract":"The object of research is a data model that characterizes the pumping units of main oil pipelines. The paper considers the creation of pumps database and their characteristics as a component of software systems designed to search for sources of energy saving in pipeline transportation of oil and oil products.<br><br>An overview of existing programs for calculating the joint operation of an oil pumping station and a pipeline is given. It is shown that most programs are inaccessible for analyzing the applied data storage technologies, or involve manual input of entry data without using databases. Comparative analysis of spreadsheets and relational databases is performed. It is shown that relational databases better meet the requirements of data convenience, availability, scalability, and performance. A physical model of a relational database is presented. The parent and child entities have been established, which make it possible to fully reflect all information about the pumping unit, namely:<br><br>– coefficients of hydraulic characteristics depending on the diameter of the impeller rotor;<br><br>– characteristics depending only on the pump make;<br><br>– classification of the pump by design or purpose. Relationship types and referential integrity rules are defined between entities when deleting or updating data. For data management, the SQLite system is proposed, which provides data manipulation in the SQL query language and does not require the development of additional software. The analysis of possible ways of organizing multilingualism using a database is carried out. The text of the SQL query is proposed, which allows to select the pump with its characteristics by the pump make and impeller diameter. A database structure is proposed that allows storing information about equipment for oil pipelines for various purposes, which makes it possible for automated calculations of complex technological processes. The pumping unit database is an open source project that is posted on the public web service GitHub.","PeriodicalId":10639,"journal":{"name":"Computational Materials Science eJournal","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83586565","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 : 2020-10-30DOI: 10.15587/1729-4061.2020.210818
T. Arini, Latifa Hanum Lalasari, L. Andriyah, N. Natasha, F. Yunita, F. Firdiyono, Adjie Maulana Syaputra, Amalia Solehah, A. Subhan
Fluorine-doped tin oxide (FTO) thin films have been deposited by the modified spin coating method at 3000 rpm using tin (II) chloride dehydrate (SnCl2×2H2O) as a precursor, ammonium fluoride (NH4F) as a dopant and ethanol as a solvent. The aim of this research is to find out the quality of the thin film based on the number of cycles (3, 4, 5, and 6 cycles) and annealing temperature (300, 400 and 500 °C). The variation of annealing temperature and number of cycles can affect the crystal structure of the FTO thin film, crystal size and grain size. Increasing the number of cycles and annealing temperature can lead to larger crystallite size and lower dislocation density, so that electrons between the grains can move easily. The large grain can reduce the grain boundary, increasing the electron mobility and decreasing the resistivity. XRD analysis shows that the structure of SnO2 polycrystalline with the most dominant crystal plane (110) is formed in this research when compared to the intensity of other structures. The resistivity value decreases with increasing the annealing temperature and number of cycles. In addition, transparency value also decreases along with increasing the annealing temperature and number of cycles. The optimum results of resistivity and transparency values obtained in this research are 1.692´10-2 Ω×cm and 69.232 % at 500 °C and 5 cycles. These results can be used as a reference for further study to optimize the production of fluorine-doped tin oxide (FTO) thin film with spin coating. Therefore, many factors that affect the production of fluorine-doped tin oxide (FTO) thin film, either dissolving stage or deposition process on the substrate surface still need to be studied deeply to obtain the optimum result.
{"title":"Controller of Fluorinedoped Tin Oxide Thin Films Deposition via Cycles and Annealing Temperatures by Spin Coating Techniques","authors":"T. Arini, Latifa Hanum Lalasari, L. Andriyah, N. Natasha, F. Yunita, F. Firdiyono, Adjie Maulana Syaputra, Amalia Solehah, A. Subhan","doi":"10.15587/1729-4061.2020.210818","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.210818","url":null,"abstract":"Fluorine-doped tin oxide (FTO) thin films have been deposited by the modified spin coating method at 3000 rpm using tin (II) chloride dehydrate (SnCl2×2H2O) as a precursor, ammonium fluoride (NH4F) as a dopant and ethanol as a solvent. The aim of this research is to find out the quality of the thin film based on the number of cycles (3, 4, 5, and 6 cycles) and annealing temperature (300, 400 and 500 °C). The variation of annealing temperature and number of cycles can affect the crystal structure of the FTO thin film, crystal size and grain size. Increasing the number of cycles and annealing temperature can lead to larger crystallite size and lower dislocation density, so that electrons between the grains can move easily. The large grain can reduce the grain boundary, increasing the electron mobility and decreasing the resistivity. XRD analysis shows that the structure of SnO2 polycrystalline with the most dominant crystal plane (110) is formed in this research when compared to the intensity of other structures. The resistivity value decreases with increasing the annealing temperature and number of cycles. In addition, transparency value also decreases along with increasing the annealing temperature and number of cycles. The optimum results of resistivity and transparency values obtained in this research are 1.692´10-2 Ω×cm and 69.232 % at 500 °C and 5 cycles. These results can be used as a reference for further study to optimize the production of fluorine-doped tin oxide (FTO) thin film with spin coating. Therefore, many factors that affect the production of fluorine-doped tin oxide (FTO) thin film, either dissolving stage or deposition process on the substrate surface still need to be studied deeply to obtain the optimum result.","PeriodicalId":10639,"journal":{"name":"Computational Materials Science eJournal","volume":"57 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74200092","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 : 2020-10-30DOI: 10.15587/2706-5448.2020.215048
Valentyna Halushko, A. Halushko, D. Uvarov, A. Uvarova
The object of research is the technology of road surface construction using alternative materials and the possibility of introducing automated systems to increase productivity. The main hypothesis of the study lies in the found alternative material, with the help of which it is possible to reduce the cost of road construction and increase the quality and service life. To reduce the cost of roads, it is necessary to create new construction technologies using innovative or alternative materials, use the latest mechanisms and introduce automated and robotic systems. This can be achieved if to carefully study the technology of the construction process device. One of the materials of the road surface is crushed stone, gravel and sand. Let’s consider as one of the alternative options for mining waste – crushed slag. When determining the main physical and mechanical properties of crushed slag, the standard method for testing crushed stone in stationary laboratory conditions was used. In the course of the study, the methods of system analysis and generalization were used, as well as the method of material testing. The authors of the work analyzed the technological processes of road construction and proposed a material based on the test results – crushed slag from a ferroalloy plant. During the tests, it was confirmed that the material is an alternative quarry crushed stone. Ferroalloy crushed stone has the same field of application, strength, density, frost resistance, but the cost is an order of magnitude less than a ton, creates an economic effect of 31.93 USD per ton. This makes it possible to reduce the cost of the road surface and ensures the quality that meets the regulatory requirements, and the production of modern technologies will reduce the time standard at some construction sites.
When testing crushed slag, the results obtained confirm that this material meets all the requirements and may well replace granite crushed stone in the construction of roads for various purposes. Such material can be used not only in Ukraine, but also in countries with similar requirements for the composition of the roadway.
{"title":"Selection of Effective Material for Road Construction","authors":"Valentyna Halushko, A. Halushko, D. Uvarov, A. Uvarova","doi":"10.15587/2706-5448.2020.215048","DOIUrl":"https://doi.org/10.15587/2706-5448.2020.215048","url":null,"abstract":"The object of research is the technology of road surface construction using alternative materials and the possibility of introducing automated systems to increase productivity. The main hypothesis of the study lies in the found alternative material, with the help of which it is possible to reduce the cost of road construction and increase the quality and service life. To reduce the cost of roads, it is necessary to create new construction technologies using innovative or alternative materials, use the latest mechanisms and introduce automated and robotic systems. This can be achieved if to carefully study the technology of the construction process device. One of the materials of the road surface is crushed stone, gravel and sand. Let’s consider as one of the alternative options for mining waste – crushed slag. When determining the main physical and mechanical properties of crushed slag, the standard method for testing crushed stone in stationary laboratory conditions was used. In the course of the study, the methods of system analysis and generalization were used, as well as the method of material testing. The authors of the work analyzed the technological processes of road construction and proposed a material based on the test results – crushed slag from a ferroalloy plant. During the tests, it was confirmed that the material is an alternative quarry crushed stone. Ferroalloy crushed stone has the same field of application, strength, density, frost resistance, but the cost is an order of magnitude less than a ton, creates an economic effect of 31.93 USD per ton. This makes it possible to reduce the cost of the road surface and ensures the quality that meets the regulatory requirements, and the production of modern technologies will reduce the time standard at some construction sites.<br><br>When testing crushed slag, the results obtained confirm that this material meets all the requirements and may well replace granite crushed stone in the construction of roads for various purposes. Such material can be used not only in Ukraine, but also in countries with similar requirements for the composition of the roadway.","PeriodicalId":10639,"journal":{"name":"Computational Materials Science eJournal","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79080978","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 : 2020-10-30DOI: 10.15587/1729-4061.2020.211793
E. Munapo
The paper presents a new method for solving the 0–1 linear programming problems (LPs). The general 0–1 LPs are believed to be NP-hard and a consistent, efficient general-purpose algorithm for these models has not been found so far. Cutting planes and branch and bound approaches were the earliest exact methods for the 0–1 LP. Unfortunately, these methods on their own failed to solve the 0–1 LP model consistently and efficiently. The hybrids that are a combination of heuristics, cuts, branch and bound and pricing have been used successfully for some 0–1 models. The main challenge with these hybrids is that these hybrids cannot completely eliminate the threat of combinatorial explosion for very large practical 0–1 LPs. In this paper, a technique to reduce the complexity of 0–1 LPs is proposed. The given problem is used to generate a simpler version of the problem, which is then solved in stages in such a way that the solution obtained is tested for feasibility and improved at every stage until an optimal solution is found. The new problem generated has a coefficient matrix of 0 s and 1 s only. From this study, it can be concluded that for every 0–1 LP with a feasible optimal solution, there exists another 0–1 LP (called a double in this paper) with exactly the same optimal solution but different constraints. The constraints of the double are made up of only 0 s and 1 s. It is not easy to determine this double 0–1 LP by mere inspection but can be obtained in stages as given in the numerical illustration presented in this paper. The 0–1 integer programming models have applications in so many areas of business. These include large economic/financial models, marketing strategy models, production scheduling and labor force planning models, computer design and networking models, military operations, agriculture, wild fire fighting, vehicle routing and health care and medical models
{"title":"Development of an Exact Method for Zero-One Linear Programming Model","authors":"E. Munapo","doi":"10.15587/1729-4061.2020.211793","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.211793","url":null,"abstract":"The paper presents a new method for solving the 0–1 linear programming problems (LPs). The general 0–1 LPs are believed to be NP-hard and a consistent, efficient general-purpose algorithm for these models has not been found so far. Cutting planes and branch and bound approaches were the earliest exact methods for the 0–1 LP. Unfortunately, these methods on their own failed to solve the 0–1 LP model consistently and efficiently. The hybrids that are a combination of heuristics, cuts, branch and bound and pricing have been used successfully for some 0–1 models. The main challenge with these hybrids is that these hybrids cannot completely eliminate the threat of combinatorial explosion for very large practical 0–1 LPs. In this paper, a technique to reduce the complexity of 0–1 LPs is proposed. The given problem is used to generate a simpler version of the problem, which is then solved in stages in such a way that the solution obtained is tested for feasibility and improved at every stage until an optimal solution is found. The new problem generated has a coefficient matrix of 0 s and 1 s only. From this study, it can be concluded that for every 0–1 LP with a feasible optimal solution, there exists another 0–1 LP (called a double in this paper) with exactly the same optimal solution but different constraints. The constraints of the double are made up of only 0 s and 1 s. It is not easy to determine this double 0–1 LP by mere inspection but can be obtained in stages as given in the numerical illustration presented in this paper. The 0–1 integer programming models have applications in so many areas of business. These include large economic/financial models, marketing strategy models, production scheduling and labor force planning models, computer design and networking models, military operations, agriculture, wild fire fighting, vehicle routing and health care and medical models","PeriodicalId":10639,"journal":{"name":"Computational Materials Science eJournal","volume":"65 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74423336","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}
Nutmeg belonging to the family of Myristicaceae, is a spice seed from the fruit of a tropical evergreen tree called M.Fragrans Houtt. Owing to the special antimicrobial properties of the essential oil extracted from nutmeg, it is known o be an excellent substitute for sodium benzoate, which is one of the common food preservative used in the market. Sodium benzoate when consumed in excess is found to be carcinogenic to human body comparing to nutmeg oil which is anti carcinogenic. Essential oils and various oleoresins extracted from nutmeg oil is proven to be anti microbial. One of the modern ways to improve the hygienic safety of manufactured food products is to exploit this anti microbial property of nutmeg oil extract. The use of nutmeg oil extract can thus reduce the health issues and turn out to be environmental friendly. This article focuses on the extraction of essential oil from nutmeg as a substitute for food preservatives and its characteristic techniques. Various methodologies like FTIR and HPLC have been carried out.
{"title":"Essential Oil Extracted from Nutmeg to be Used as Substitute for Food Preservatives","authors":"S. M, Saumya Mohan","doi":"10.2139/ssrn.3721532","DOIUrl":"https://doi.org/10.2139/ssrn.3721532","url":null,"abstract":"Nutmeg belonging to the family of Myristicaceae, is a spice seed from the fruit of a tropical evergreen tree called M.Fragrans Houtt. Owing to the special antimicrobial properties of the essential oil extracted from nutmeg, it is known o be an excellent substitute for sodium benzoate, which is one of the common food preservative used in the market. Sodium benzoate when consumed in excess is found to be carcinogenic to human body comparing to nutmeg oil which is anti carcinogenic. Essential oils and various oleoresins extracted from nutmeg oil is proven to be anti microbial. One of the modern ways to improve the hygienic safety of manufactured food products is to exploit this anti microbial property of nutmeg oil extract. The use of nutmeg oil extract can thus reduce the health issues and turn out to be environmental friendly. This article focuses on the extraction of essential oil from nutmeg as a substitute for food preservatives and its characteristic techniques. Various methodologies like FTIR and HPLC have been carried out.","PeriodicalId":10639,"journal":{"name":"Computational Materials Science eJournal","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75693688","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}
A. E. Danon, O. Muránsky, H. Zhu, T. Wei, E. Flores-Johnson, Z.J. Li, J. Kruzic
The mechanical performance of a Ni–Mo–Cr (GH3535) alloy weldment, produced using a matching filler metal, was assessed and compared to the surrounding parent metal. Ambient-temperature mechanical characterisation included hardness testing, small punch testing and uniaxial tensile testing, while a crystal plasticity finite element model was used to assess the impact of crystallographic texture on the mechanical properties. Despite the similar chemical composition, the weld metal exhibited superior strength and ductility to that of the parent metal. The higher strength was primarily attributed to the high dislocation density in the weld metal imbued by the welding-induced thermo-mechanical loading. In contrast, the ductility difference was attributed to M6C carbide stringers in the parent metal that initiated fracture at lower strains than for the weld metal, with the latter containing much finer, well-dispersed M6C carbides.
{"title":"The Effect of Microstructure and Welding-Induced Plasticity on the Strength of Ni–Mo–Cr Alloy Welds","authors":"A. E. Danon, O. Muránsky, H. Zhu, T. Wei, E. Flores-Johnson, Z.J. Li, J. Kruzic","doi":"10.2139/ssrn.3721067","DOIUrl":"https://doi.org/10.2139/ssrn.3721067","url":null,"abstract":"The mechanical performance of a Ni–Mo–Cr (GH3535) alloy weldment, produced using a matching filler metal, was assessed and compared to the surrounding parent metal. Ambient-temperature mechanical characterisation included hardness testing, small punch testing and uniaxial tensile testing, while a crystal plasticity finite element model was used to assess the impact of crystallographic texture on the mechanical properties. Despite the similar chemical composition, the weld metal exhibited superior strength and ductility to that of the parent metal. The higher strength was primarily attributed to the high dislocation density in the weld metal imbued by the welding-induced thermo-mechanical loading. In contrast, the ductility difference was attributed to M6C carbide stringers in the parent metal that initiated fracture at lower strains than for the weld metal, with the latter containing much finer, well-dispersed M6C carbides.","PeriodicalId":10639,"journal":{"name":"Computational Materials Science eJournal","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78916706","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}
Reliable diagnostic framework must have the ability to deal with many diagnostic conditions, including the cases of multiple faults in bearings. Timely and reliable fault detection and assessment in such cases are of utmost importance for the prevention of missed detections, inadequate maintenance, and loss of profits due to failures. The problems of multiple fault diagnosis attracted relatively little attention in the literature on the background of common interest to improvements in single fault diagnosis. Multiple fault diagnosis has additional, in comparison to single fault diagnosis, challenges: submergence of the weak fault by the strong fault, overlap of vibration characteristics in time and frequency domains, coupling of frequency components and so on. To address these challenges, several solutions were proposed, including those based on artificial intelligence. However, majority of intelligent methods relied on manual feature extraction based on prior information of the faults and a new problem usually requires a new design of the feature extractor. Deep learning is a promising tool to cope with known challenges of commonly proposed intelligent methods. This paper presents a new learning-based framework to improve the efficiency of the fault diagnosis in the case of multiple faults of bearings. Deep learning integrated into the framework helps to overcome the challenges of manual feature engineering, while maintaining good diagnostic efficiency. Inputs to the classification stage are presented by versions of the dataset using generic signal processing techniques. Results from this method demonstrate promising outcomes in the detection and classification of multiple faults.
{"title":"Learning-Based Diagnosis of Multiple Faults in Bearings","authors":"Udeme Inyang, I. Petrunin, I. Jennions","doi":"10.2139/ssrn.3718031","DOIUrl":"https://doi.org/10.2139/ssrn.3718031","url":null,"abstract":"Reliable diagnostic framework must have the ability to deal with many diagnostic conditions, including the cases of multiple faults in bearings. Timely and reliable fault detection and assessment in such cases are of utmost importance for the prevention of missed detections, inadequate maintenance, and loss of profits due to failures. The problems of multiple fault diagnosis attracted relatively little attention in the literature on the background of common interest to improvements in single fault diagnosis. Multiple fault diagnosis has additional, in comparison to single fault diagnosis, challenges: submergence of the weak fault by the strong fault, overlap of vibration characteristics in time and frequency domains, coupling of frequency components and so on. To address these challenges, several solutions were proposed, including those based on artificial intelligence. However, majority of intelligent methods relied on manual feature extraction based on prior information of the faults and a new problem usually requires a new design of the feature extractor. Deep learning is a promising tool to cope with known challenges of commonly proposed intelligent methods. This paper presents a new learning-based framework to improve the efficiency of the fault diagnosis in the case of multiple faults of bearings. Deep learning integrated into the framework helps to overcome the challenges of manual feature engineering, while maintaining good diagnostic efficiency. Inputs to the classification stage are presented by versions of the dataset using generic signal processing techniques. Results from this method demonstrate promising outcomes in the detection and classification of multiple faults.","PeriodicalId":10639,"journal":{"name":"Computational Materials Science eJournal","volume":"56 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90855072","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}
Duaa Alrufaihi, Audrey Fernandes, Bhavya Gangar Jaysukh, Pauline Goldery, R. Kaur, Samuler Tirado Alvarez, Daniel Vazquez Navarro, K. Salonitis
Poor quality costs are the total financial losses caused by the products or services not being perfect. Process scrap is a major contributing factor to these losses. Identification of different sources of scrap and the resulting costs is paramount for Continuous Improvement. Furthermore, quantification of this scrap and how the data can be visualised will facilitate decision making by upper management. For this, a methodology that acts as a guide will prove to be of great use in the analysis of scrap generation in any manufacturing plant. In the case study presented, a comprehensive list of the possible sources was made. However, only those which were responsible for a major part of the cost and of great concern were shortlisted. Once identified, several measurement systems were proposed to accurately quantify the resultant scrap. This was then followed by data visualisation using a dashboard that gave a weekly update on the levels of scrap generated.
{"title":"Methodology to Identify and Quantify Sources of Process Scrap on Shop Floor","authors":"Duaa Alrufaihi, Audrey Fernandes, Bhavya Gangar Jaysukh, Pauline Goldery, R. Kaur, Samuler Tirado Alvarez, Daniel Vazquez Navarro, K. Salonitis","doi":"10.2139/ssrn.3718046","DOIUrl":"https://doi.org/10.2139/ssrn.3718046","url":null,"abstract":"Poor quality costs are the total financial losses caused by the products or services not being perfect. Process scrap is a major contributing factor to these losses. Identification of different sources of scrap and the resulting costs is paramount for Continuous Improvement. Furthermore, quantification of this scrap and how the data can be visualised will facilitate decision making by upper management. For this, a methodology that acts as a guide will prove to be of great use in the analysis of scrap generation in any manufacturing plant. In the case study presented, a comprehensive list of the possible sources was made. However, only those which were responsible for a major part of the cost and of great concern were shortlisted. Once identified, several measurement systems were proposed to accurately quantify the resultant scrap. This was then followed by data visualisation using a dashboard that gave a weekly update on the levels of scrap generated.","PeriodicalId":10639,"journal":{"name":"Computational Materials Science eJournal","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77973024","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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