bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative analysis of chatter in micro end milling operations
Authors: Busuyi Omodaratan , Ogunmola Bayo Y. , Obafemi Olatunji O. , Ishola Felix , Adedeji Paul A. , Aworinde Abraham K.
Published: April 2021

The advancement in microfabrication in pursuit of miniaturization is cutting a dynamic role for micro-milling. Micro-milling is a fast and cost-efficient threedimensional fabrication method with the ability to achieve good accuracy, low surface roughness and extraordinary material removal rate (MRR) compared to some other micro manufacturing processes. Given the need for components with high dimensional integrity, identification of appropriate machining conditions is very vital to getting good surface finish. It is also required to couple different complex dynamics which are associated with this machining technique. Chatter during milling and micro-milling process bring adverse effects in surface quality, dimensional accuracy and in tool life. There is need for versatile modelling of micro end-milling dynamics in order to understand how chatter affects the micro end milling operation and to advance the synthetic application of several chatter stability parameters to overcome the limitation imposed by the single chatter stability criterion. This study performs a linear and non-linear analysis of chatter in micro end milling based on the major influential parameters. In addition, a detailed time domain simulation for micro end milling was performed to predict the force a displacement resulting from variable cutter geometries. This dynamic simulation results have significant impact on the actual micro milling process towards the manufacturing of miniaturized parts.
Rural Household Space Cooling and Lighting through a Solar Power-based Electric Supply System
Authors: Awelewa A.A. , Okoma C. , Popoola O.M. , Olajube A.A. , Samuel I.A.
Published: April 2021

Quite a number of households in the world still lack electricity, especially in the sub-Saharan African continent. However, the abundance of solar irradiation in tropical Africa can be advantageously exploited to serve the inhabitants in this region, particularly the extremely low-income earners who not only have access to very inadequate power supply but also experience much discomfort in terms of poor ventilation and heat-triggered infections. This paper focuses on developing a small household-sized solar power-based electric energy supply system together with a temperature control circuit to power a direct current (DC) fan, and a light-regulating circuit to control LED lamps—with additional features such as a digital clock, a remote control, and mobile phone charging units. The system also has a provision for power supply through the mains (whenever it is available). The overall intent is to provide the rural dwellers with a cost-effective way of powering essential devices for basic economic living. This affordable solution is designed, simulated, and constructed to have hardware and software sections supported by various components and devices such as Arduino Mega, Lm35 sensor, RF transceivers, diodes, transistors, regulators, batteries, lamps, a DC fan, etc. The sensor senses room temperature, which is compared with the reference temperature of 25°C programmed on the Arduino microcontroller. When the temperature is less than 25°C, the fan remains stationary but when the temperature is higher than the reference value, the fan begins to run. As the temperature rises further, the speed of the fan increases to maintain adequate ventilation.
Development and Performance Evaluation of a Simple Batch Reactor for Leaching of Potassium Ash
Authors: Adeodu A. O. , Emmanuel A. A. , Daniyan I. A , Bello K. A
Published: April 2021

Leaching is ubiquitously used operation for extracting a substance from a solid matrix through interaction between the solid matrix and liquid. Most batch reactors with fairly advanced sophistication are very costly while the less costly ones are of low performance and have quality challenge. The aim of this paper is to develop a simple batch reactor that uses continuous stirred action to leach caustic potash from potassium ash derived from cocoa pod husk. The batch reactor is made up of a hopper for the passage of the feed to the cylindrical vat, variable speed motorized stirrer, filter mesh, basket filter, heating/cooling system, temperature controller, temperature sensor attached to the heating/cooling system. The design has it novelty by the incorporation of temperature controller and sensor to the heating/cooling system. The criteria for the materials selection of the design were strength, corrosion resistance, machinability and economic value. The consideration of the design was based on existing machine design theories. The performance assessment showed that the reactor is capable of leaching caustic potash from potassium ash derived from cocoa pod husk on the basis of 1 Tonne per day. It was discovered that there is a direct relationship between leaching time and mass of caustic potash extracted and an inverse relationship between the leaching time and mass of sludge. At a leaching time of 30 minutes, the mass of the potash leached was 45kg and the mass of sludge was 30kg, whereas, at a time of 45minutes, the mass of caustic potash increased to 75kg and the mass of the sludge decreased to 25kg. From the evaluation, the efficiency of the machine is 74.14%. The development of a 1ton/day potassium ash leaching reactor was achieved. The machine is useful for processing of caustic potash in reasonable time and quality.
Advanced Manufacturing Technology in Nigeria: A Review
Authors: Akintayo T. C. , Akinlabi S. A. , Okokpujie I. P. , Ishola F. , Akinlabi E. T.
Published: April 2021

This paper reviews the present state of the act of advanced manufacturing technology of the manufacturing in the Nigerian economy. Furthermore, this review also carried out a study on the current trend of an advanced level of operation of the manufacturing industry in Nigeria. In this study, some key changelings are identified, and possible solutions are recommended on why the innovative technology is yet to be embraced and implemented despite the vast and fantastic contribution it could impact on the socio, economic, and political development of the nation. This study will assist the Government of Nigeria to make a move in developing strategic plans on replacing the local manufacturing process to the advanced manufacturing technology (AMT) to strengthen the economy of the nation further.
Development of a Small Hydropower Plant (SHP); A Review Study of Erin-Ijesa Water Fall, Erin-ijesa, Osun State, Nigeria
Authors: Odunfa K.M. , Rosiji Y.O. , Owoseni O. D.
Published: April 2021

Energy demand has been on the increase globally due to the increase in population, urbanization and industrialization. In developing countries, while the rate of energy consumption is increasing, supply which is usually produced from fossil fuels is depleting resulting in energy shortage and pollution. Hence the need to explore alternative or renewable sources of energy to meet current and future energy demand. This paper examines the potential of Erin-Ijesa waterfall as a possible source of power supply to Erin-Ijesa community. The erratic supply of electricity in Nigeria, Erin-Ijesa community inclusive makes it paramount to consider generating electricity from the waterfall. Towards achieving this, the waterfalls data were obtained from Osun State Water Corporation Board Secretariat in Osogbo and a survey was conducted on site at Erin-Ijesa water falls where the flow and the head parameters were collected. The falls gives gross head of 200m with water flow rate of 0.85m3/s. These two parameters were used in the standard hydroelectric power (SHP) equations. The results obtained gave a theoretical power of 1.4MW, compared with the required power consumption of 1MW by the inhabitants of Erin-Ijesa community. A deviation of +0.4 from the required power consumption. It was also observed that the generated power from the falls will be sufficient to supply the entire community. The viability of small hydropower plant and the reduction in design time were established. Small hydropower plant will perform well if explored and executed in Erin-Ijesa, and in Nigeria at large.
Physicochemical Properties of Wood Sawdust: A Preliminary Study
Authors: Oyebanji J.A. , Okekunle P.O. , Oyedepo S.O. , Fayomi O. S. I.
Published: April 2021

In this study, the physicochemical properties such as proximate, ultimate analysis and heating value of five wood species sawdust (WSD) samples have been determined. The Higher Heating Values (HHVs) of the samples were estimated as functions of fixed carbon (FC) and volatile matter (VM), and were also calculated from an elemental composition-based correlation equation. Results showed the ranges of VM and FC were 74.95 – 75.74% and 14.25 – 14.80%, respectively. The High Heating Values (HHV) of Iroko, West African Entada, Ebony, African cam and Rough chaff, according to ultimate analysis-based correlation equation, were found to be 18.85, 18.77, 18.75, 18.55 and 18.52 MJ kg-1, respectively while according to proximate analysis-based correlation equation, were 18.41, 18.53, 18.43, 18.50 and 18.14 MJ kg-1. The high percentage of VM and the value range of FC resulted in appreciable HHVs for the samples. It can be concluded that woody biomass residues are good sources of bio-fuels for sustainable development.
Overview Impacts of Heat Treatment Techniques on Grain Structures of a Steel
Authors: Afolalu S. A. , Salawu E.Y. , Joseph O. O. , Oladipupo S. , Emetere M. E. , Ongbali S.O. , Abioye A.A. , Akinlabi S.A
Published: April 2021

In this study, various techniques used in the modification of the grain structure of steel were considered. It was found that different heat treatment techniques cause changes in the grain structure of steel and subsequent improvement in the mechanical properties of the material. More so, the bimodal grain size, as well as the lamellar structure in steel, will lead to work hardening effect and improved ductility of the steel. The carburization technique also improves the mechanical properties such as hardenability, compressibility, tensile strength, and toughness. While nitriding effects will lead to excellent tribocorrosion performance. More importantly, these heat treatment techniques help to improve the resistance against cyclic load in different application environments. Thus, failures resulting from crack propagation and other failure modes are prevented. In this regard, structural failures are prevented by grain structure modification using heat techniques.
Evaluation of Factors influencing the decision to utilizing ICT-based tools in Construction Project and Planning
Authors: Pedro O. , Afolabi A.O. , Abba T. , Ajibola P.
Published: April 2021

Construction planning represents one of the most critical activities in the construction process. This is because it can help predict the failure or success of a construction project. It can also influence the construction project performance in terms of time, cost, and project quality. However, with the advent of information and communication technologies (ICTs) tools in the construction sector, some construction professionals still utilize manual-based tools. Therefore, this study was aimed at evaluating the factors influencing the decision to use ICT based tools in construction planning. The empirical study utilized a questionnaire instrument to sample 70 construction professionals regarding the subject matter. The data collected was analyzed using compare mean scores, principal factor analysis, and categorical regression. The study showed that level of computer literacy, availability of the ICT tool, and performance expectations played an essential role in the decision to utilize ICT-based tools in construction planning. These decision factors were further categorized into Comparative advantage factors, Operational factors, and Individuals/Project factors. The study showed that there were significant factors that can influence the decision to utilized ICT-based tools. These crucial factors include performance expectancy and facilitating conditions. The study recommended the need to increase access to construction planning software and provide necessary ICT infrastructure to facilitate the usage of available ICT-based tools.
Digital Technologies and Construction Planning
Authors: Abba T. , Afolabi A. O. , Ajibola P. , Olanrewaju P.
Published: April 2021

The construction industry is very vital as it helps provide the necessary buildings and supporting civil infrastructure. However, the problems of productivity, poor planning and poor coordination has not allowed it to maximize its full potential. The use of digitalized solutions in coordinating and planning construction activities can help resolve these challenges. Therefore, the study was aimed at investigating the digital technologies available to construction professionals during construction planning. The study utilized the data instrument of a well-structured questionnaire. A total of 110 construction professional took part in the survey research. The study showed that Microsoft Project, Primavera and Web-based Project Management System are the most used digital technologies in construction planning. Construction professionals identified the benefits of improved quality, better record keeping, and time saving benefits in the use of digital technologies for construction planning. The study showed that there was statistically significant difference in the benefits such as reduction in construction errors, increased flexibility, and access to information in real time. It recommended that construction professionals should increase investment in innovative digital solutions in order to address the challenges facing the construction industry.
A Simplified Design for Biodiesel Production
Authors: Ayoola A.A. , Alagbe E.E. , Agboola O. , Ayeni O.A. , Adeyemi G.A. , Nnabuko D. , Makinwa T.A.
Published: April 2021

In this research work, a simple design for the production of 1kg biodiesel involving two stage esterification-transesterification process, with the use of waste soybean oil (WSO) and NaOH catalyst was considered. CHEMCAD 7.1.2 software was used for the design operation which revealed that four (4) pumps, four (4) heaters, two (2) mixers, one (1) drying equipment and two (2) reactors were involved. Also, the production process design revealed that 0.0513kg/hr of methanol and 0.1800kg/hr of 0.1M H2SO4 were required during the esterification process. While 0.6921kg/hr of methanol, 0.9870kg/hr of WSO as well as 0.1934kg/hr of NaOH catalyst were needed for the transesterification process. The simplicity of the design and high purity level of the biodiesel produced adjudged the design operation good.
Exploring Bandgap Engineering on Photovoltaics and their Possible Economic implications
Authors: Abodunrin T.J. , Emetere M.E. , Ajayi O.O. , Popoola A.P.I. , Popoola O. , Uyor U.O.
Published: April 2021

Bandgap an intrinsic property of molecules on nanoscale, has capability of making alterations in the characteristics of the material through cataclysmic changes from interaction with light. Ultraviolet spectrographs of three organic extracts were explored for their optical frequency and possible use as communication organic optical fiber. The bandgaps of these dye extracts were determined and tailored by varying their absorptivity of ions in electrolytic solvents. A distinctive absorption power, transmittance and amplitude promoted vital regional shifts in wavelength. Interaction with radiation absorbed, influenced a Fermi energy change within a large band gap ≈ 4eV, which is a hypothetical line of symmetry. Results revealed that all the bands below that energy level were entirely filled, whereas all higher-lying bands were completely or nearly empty, with the exception of minimal thermal excitation which is induced at high temperatures.
Titanium Dioxide Nanotube Fabricated at Ambient Temperature via pH5 Acidic Solution
Authors: Araoyinbo A O , Oyedepo S O , Fajobi M A
Published: April 2021

This study focuses on the fabrication of titanium dioxide TiO2 via a pH 5 acidic solution of hydrofluoric acid to produce a nanotube structure of titanium dioxide (TiO2). The anodization processes of some metals have been a well-known method over the years in converting metal foils into its oxide form due to its strong affinity with oxygen. Titanium foils have also been used in this way to convert the metal into its oxide form which has found use in many areas of application. The anodizing method is a simple process but requires knowledge of the key parameters to be suitably controlled in the fabrication of the nanotube structure without destroying the oxide layer initially formed on the surface. The parameters used include a pH 5 of the HF solution, anodizing time of 10 minutes, and a 20 V applied potential from a direct current power supply. After the anodization process the heat treatment of the samples was performed at 300, 500, and 700°C to observe the phase transformation from an amorphous titanium dioxide to anatase and rutile phase. The surface morphology was observed using field emission-scanning electron microscope, energy dispersive x-ray to identify the percentage of the elemental composition present after the anodization process and the phase changes by x-ray diffraction (XRD).
Effect of Machining of Aluminium Alloys with Emphasis on Aluminium 6061 Alloy – A Review
Authors: Samuel A U , Araoyinbo A O , Elewa R R , Biodun M B
Published: April 2021

Aluminium alloy is one of the most widely used engineering materials due to their relatively lower specific weight and corrosion resistance compared to steel. Besides, they are also relatively easier to machine. Aluminium alloys have been found to provide the highest degree of machinability compared to other lightweight metal such as titanium and magnesium alloys. Among every other type of aluminium alloy, the 6061 aluminium alloy has been used for general purposes due to some interesting attributes it possesses when compared to others. The investigation on the effect of machining condition on the corrosion of 6061 aluminium alloy has shown that the machining via electrical discharged provides better resistance to pitting corrosion than the diamond and carbide turning machine. Drilling, turning and cutting may influence the mechanical characteristics of the workpiece by producing hole opening around the low residual stresses and a small layer of extremely stressed material on the newly created surface, making it to become more prone to fatigue, crack propagation and corrosion at the stressed surface. The machining surface integrity has great influences on the fatigue lifetime of material since micro-cracks always initiate at the surface. The traditional machining techniques compared to the non-traditional or non-conventional techniques are more susceptible to the induction of poor surface integrity due to direct contact between the tool and workpiece which are characterised by several damage defects such as micro-cracks, surface hardening, roughness and residual tensile. This paper therefore provides an overview of the classes of aluminium alloys, there applications and machining of the alloys with a keen focus on 6061 aluminium alloy and exposition of various machining technique with both their beneficial and non-beneficial effects on the workpiece, tool life and the environment.
Experimental Assessment of Properties of Earth Soil Used in Concrete Production
Authors: Ogunbayo BF , Aigbavboa OC , Ogundipe KE , Akinradewo OI , Amusan LM , Afolabi AO
Published: April 2021

Soil as an aggregate material is one of the major ingredients for concrete production. One of the soils used as a fine aggregate material for general construction most especially concrete production is the earth soil without resorting to its properties and mechanical analysis. It is based on this that the study assessed the physical properties of the earth soil and mechanical properties of concrete produced through it. In assessing the physical properties’ quality of the earth soil sampled analysis such as grain size distribution, percentage of silt content, water absorption, loose and rodding bulk density, specific gravity, and percentage of void were carried out. Also, mechanical properties of concrete produced with the earth soil were carried out using the compressive strength testing machine. The finding of the study showed that the result of the property analyses carried out on the earth soil does not meet the expected result as stipulated in ASTM C29 / C29M-17a. Also, the result of the mechanical properties of the concrete produced showed that the strength of the concrete decrease as the age of the concrete progresses from 11.23% (7 days), 6.87% (14 days) to 13.12% (28 days). The study suggested that the earth soil is not a standalone aggregate material suitable for construction work most especially concrete production. The study concluded that to boost the property quality of the earth soil, a certain percentage of the aggregate should be stabilized using a well graded fine aggregate material such as river sand in order to boost it suitability for general construction work most especially concrete production.
Application of laccase in aflatoxin B1 degradation: a review
Authors: Okwara P.C. , Afolabi I.S. , Ahuekwe E.F.
Published: April 2021

The second component of the sustainable development goals, which is focused on zero hunger can only be actualized when safety issues that affect food security are tackled. In addressing food safety issues, the decontamination of aflatoxin b1 is a priority. Aflatoxin b1 is a class of mycotoxin that predominantly contaminates crops and their derivative processed foods. It has been reported to trigger the formation of cancer cells as well as pose a serious health challenge in humans that consume the contaminated food. The effective use of laccase enzyme (a ligninolytic enzyme) as an agent of bioremediation for wastewater and industrial effluent treatment initiated its use in aflatoxin degradation. This review highlights the potentials of laccase enzyme as a useful tool in aflatoxin b1 degradation. Also considered is the proposed mechanisms by which laccase enzyme catalyzes aflatoxin b1 degradation, and the factors affecting laccase activity such as temperature, ph, mediators and inhibitors. Studies have shown that due to the non-phenolic characteristic of aflatoxin b1, laccase-catalyzed aflatoxin degradation requires a long time, and was more effective in the presence of a mediator. Various reports observed different degradation time from 55 mins to 72 hours. Such degradation could be > 50 % after 48 hours of exposure to laccase. Furthermore, the use of laccase prevents the presence of chemical residue after treatment giving it advantage over the application of the existing chemical methods. This method provides a safer means of degrading aflatoxin b1 with minimal loss of the nutritional quality of treated food sample.
Application of Digital Logic Method in the Selection of Suitable Polymeric Materials for Ceiling Tiles Production
Authors: Balogun O. A. , Adediran A. A. , Akinwande A. A. , Olayanju T. M. A.
Published: April 2021

Polymeric materials are widely employed in the production of ceiling tiles due to their attractive qualities such as thermal insulation, low water absorption characteristics, light weight, availability, cost effectiveness and their good surface finishing. This study focused on the production, property characterization and the optimization of five different polymer composite material which are 20SE (20 wt.% of sisal reinforced epoxy), 20JH (20 wt.% jute fiber reinforced high density polyethylene), 20BP (20 wt.% bagasse fiber reinforced polypropylene), 6CP (20 wt.% coconut shell ash reinforced Polyvinyl chloride) and 20CL (20 wt.% cotton reinforced low density polyethylene). Selected properties considered are flexural and tensile strengths, thermal conductivity, water absorption and bulk density. The values obtained after characterization were evaluated using digital logic method so as to determine the composite material with the optimum property while putting their cost effectiveness into consideration. The result showed that 20BP (20 wt.% bagasse fiber reinforced polypropylene composite) had the highest performance index and figure of merit, making it the most preferred polymeric composite for ceiling tiles application.
Computational Modelling of the Effect of Coiling on Haemodynamics in Cerebral Aneurysms
Authors: Onyishi H. O. , Oluah C.K. , Ejenakevwe K.A , Jacobs I.O. , Anyaoha C.O.
Published: April 2021

This paper reports the effect of coiling on haemodynamics in cerebral aneurysms. The flow of blood into aneurysms usually leads to rupturing which is fatal. To prevent this flow, coils could be inserted into the aneurysm. The simulations of the haemodynamics in such a coiled aneurysm have been carried out using state-of-the-art computational fluid dynamics, CFD, software. To have a basis of analysis and comparison, the haemodynamics of the uncoiled aneurysm is also simulated and reported. To ensure grid independence, the mesh size for the first case is refined until there is convergence in the results obtained. The results obtained show that blood flow into the aneurysm can be stopped by coiling the aneurysm, thereby preventing rupture of the aneurysm.
Didactic Analysis Of Active-Passive Fire Safety Measures In Tejuosho Ultra Modern Market Complex, Yaba, Lagos
Authors: Aderonmu P. A. , Eghobamien O.V.
Published: April 2021

Fire outbreaks are a leading cause of loss of property and lives in the Nigerian market scene and its neighbouring areas. Although this menace of market fire outbreak has been a recurring index since the early 2000s up till now, a lot of marketplaces still do not have standard fire protection measures in place to prevent fire spread. Neither are they adequately equipped for efficient fire outbreak control. This study investigated the existing active and passive fire safety measures adopted in Tejuosho ultramodern market to create policy guidelines for effective fire safety management practices. This study was carried out in Tejuosho market, Yaba, Lagos because it is one of the most recent market developments where effective fire protection strategies were put in place. Primary data for this research was obtained employing observation and questionnaires. The study revealed that all the active fire protection measures put in place have been well maintained, regularly serviced, highly effective and supported by the passive measures. This study recommended didactic procedures and strategies accessible to the market users and traders whenever an emergency fire outbreak occurs.
Effect of Heat Treatment Methods on the Fatigue Behaviour of Hammermill: A Review
Authors: Edun B.M. , Ajayi O. O. , Babalola P.O. , Salawu E.Y.
Published: April 2021

The production of reliable and sustainable hammermill involves heat treatment which is part of overall cost of production. Heat treatment has engrossed a lot of interests since it is one of the main production methods to improve corrosion resistance of coatings, enhancing malleability, hardness and strength to lessen mechanical or chemical damage. Nevertheless, various heat treatment procedures had resulted to hammermill failure as a result of material wear, erosive wear, impact wear, machine clogging and shock loading wear which eventually affects the efficiency of the hammermill. The study thus engrossed on some particular thermal treatment on mild steels and their impacts on hammermill applications. Progressive loss of material (wear) is a common failure that leads to hammermill fatigue due to cyclic stress posed on the hammers based on literature reviews. The mode of quenching and especially the discrepancy in the concentration affects the efficiency of the crushing unit. The fatigue performance of materials is being enhanced due to stress-relief heat treatment which makes it possible to increase the strength and ductility of the samples. However, the utilization of experimental model and simulation approach for stress prediction for the study is further recommended.
Passivation behaviour and localized corrosion activities of non-toxic surfactant derivatives on Copper
Authors: Elendu I.O. , Odulanmi O.A. , Fayomi O.S.I. , Williams A.B. , Daramola M.
Published: April 2021

In this paper surfactant extracted from Zea mays was experimented on as a corrosion inhibitor for Copper in 0.5 M HCl solution using electrochemical measurement at 298 K at several surfactant concentrations. Open circuit potential measurement, polarization analysis, adsorption, SEM/EDX analysis, were investigated to find out how effective the surfactant is as an inhibitor on Copper. Results gotten depicts that the surfactant extracted from Zea mays performed excellently on Copper as the peak efficiency of inhibition of 86.99% at 20ml. The electrochemical polarization data revealed the inhibitor behaves as an inhibitor of the anodic type. Temkin isotherm of adsorption explained the surfactant adsorption onto the copper layer. SEM/EDX studies indicated that the corrosive impact on copper surface reduced due to the addition of the surfactant. The polarization tests have shown strong concordance with the SEM images.
Information and Communication Technologies for construction services in South Africa: A PROCSA Scope
Authors: Odubiyi T.B. , Aigbavboa C. O. , Thwala W. D.
Published: April 2021

The Professional Client/Consultants Service Agreement Committee (PROCSA) document describes the scope of construction services in South Africa into six stages spanning from stage 0 to stage 6. This study identified the ICT tool used from the project initiation (stage 0) to the construction (stage 5) in the South African construction industry. In this research, construction is classified into the planning, design/estimation, and actual construction. This study determines the ICT tools used in South Africa for construction activities. Through a questionnaire survey for construction stakeholders. An exploratory factor analysis revealed three clusters for the planning, two for the design/estimation, and three for the actual construction. As an implication, this study provides a framework for ICT tools as an infrastructure for development.
Oxidation and Corrosion properties of a Novel Al15Ti30Si30Mo15Ni10 High Entropy Alloy fabricated by Spark Plasma Sintering Technology
Authors: Kanyane L. R. , Popoola A.P.I , Malatji N. , Mthisi A , Fayomi O.S.I
Published: April 2021

The need for new advanced high temperature materials is in high demand. High Entropy Alloy (HEAs) has been described to possess excellent mechanical oxidation and good corrosion resistance properties even far above the ambient temperature. Attempts are made in this research to study the corrosion, oxidation, microhardness and densification properties of Al15Ti30Si30Mo15Ni10 HEA produced by spark plasma sintering (SPS) for high temperature applications. In addition, the effects of SPS temperature (800, 900 and 1000°C) on the microstructure and phase formation of the developed HEA were reported. The microstructural modification and phases present were examined using the scanning electron microscope (SEM) equipped with the energy dispersive spectroscopy (EDS) and X-ray diffractometer (XRD) respectively. Ordered FCC and BCC systems were identified along with clearly defined crystal lattice along with Mo, Ti and Si rich regions were observed. No pores or cracks were observed from the microstructures. Densification of 98.8% accompanied with microhardness of 1445.29HV was achieved for both HEA at 1000°C. The Al15Ti30Si30Mo15Ni10 HEA fabricated at 1000°C displayed a higher polarization value of 3477 Ω.
Geo located alert via bottom up IoT model in times of COVID-19 and other disasters
Authors: Lekshmy H O , Krishnaprasad T R , Vishwanath Gupta G , Namitha K
Published: April 2021

Various disasters either man made or natural have necessitated people around the world to adopt ad-hoc practices in managing or mitigating the aftermath of the disaster. In times of a pandemic or prolonged flood or war it is even more pertinent that people do not detach up on the precautionary/advisory measures. This paper proposes a mechanism integrating a mobile app with other IoT devices, using which the public can participate in issuing a broadcast alert in their locality.
Reviewing the Challenges in Maintaining the Reliability and Accuracy of IOT Systems for Remaining Useful Life Prediction
Authors: Sekar Kalaiarasan , Shah Shahani Aman , Antony Athithan A
Published: April 2021

Internet of things (IoT) has been implemented in aviation predictive maintenance in recent years for the enhancement of better maintenance prediction, to reduce downtime, unnecessary maintenance actions, increase safety, increase system readiness, and refine the management process and to improve component design. The IoT system in predictive maintenance is very optimistic in gathering and analysing, predicting the component failures and to determine the remaining useful life of a systems. Since Remaining useful life of an system is defines as the length from the current time to the end of its useful life. Due to its futuristic increasing demand of IoT in aviation maintenance, the biggest challenge is to ensuring the reliability and accuracy of any specific IoT system allotted for monitoring aircraft components in the near future. Hence, this review paper clearly explains the challenges associated with IoT systems on predicting Remaining useful life.
Design Study of an Electric Motorcycle Chassis Obtained using Topology Optimization
Authors: Ahmad Mohammad Irfan , Dorlikar Pankaj
Published: April 2021

Rising Carbon emission and associated pollution forcing government of India to make stringent emission norms and policies. Hence, it is need of the hour to switch to alternative fuels such as electricity. About 60% of the petrol consumption in India is attributed to the motorcycles and there hasn’t been significant research in the electric mobility in motorcycles. This work is based on study of an electric motorcycle chassis with integrated battery-pack space that has been obtained as a conceptual geometry using topology optimization. The layout of the chassis for this work has been obtained by applying topology optimization on a design domain representing a space obtained on the basis of presently available dimensional measurements of commuter segment motorcycles in India. The chassis has been subjected to linear static and modal analysis for further enhancing the strength, stiffness and natural frequency using the design study approach on critical region.
The thermal and stress analysis of disc brake
Authors: Sainath Alampally , Dehadray Prathamesh Mahesh , Bharath P. , Rao Lokavarapu Bhaskara
Published: April 2021

Braking system has huge importance in vehicles. The disc brake is one of the most important amongst the brake rotors. Brake rotors generate opposing torque on the shaft of the wheel thus converts the kinetic energy of the wheel to heat. The braking components are used to decelerate the vehicle by friction developed on to the wheel when brake is applied. The heat is produced during friction, which will cause negative effects on the brake assembly. This study is to analyze the motor cycle disc brake, which affects the surface of the disc. In order to get those effects on the disc surface the thermal stress analysis and thermal deformation is analyzed using ANSYS. This analysis is used to avoid the damage of the disc due to heat generation. In this study, different materials are compared to choose optimum one for the better performance to deformation, temperature and stresses.
Improving Sound Absorption coefficient and analysis of polyurethane foam reinforced with wood powder
Authors: Gokul M , Gowtham T , Jeyanthi S , Lenin babu M C , jayamani Elammaran
Published: April 2021

When it comes to acoustic insulation Polyurethane foam plays a very vital role for various sound absorption applications. The interest of this paper is to spot out the best combination of bio-based porous materials to obtain the best acoustic property. Here the porous materials used are polyurethane foam, pine wood with air gap. The sound absorption depends on the material properties such as Flow resistivity, porosity, tortuosity, thermal characteristic length and physical characteristic length, the different combinations of materials with air gap are being tested for sound absorption coefficient using impendence tube method using COMSOL. The results are being compared with numerical values obtained using impedance tube that helps us to present the best combination which provides the maximum sound absorption.
The use of programs complexes “Ansys” and “Plaxis 3D” in assessing the influence of the density of sand base on the modulus of deformation
Authors: Antonov V , Al-Naqdi I , Monastyrev P , Pakhomova E , Amelin V
Published: April 2021

The article presents a comparison of the values of the soil deformability characteristics obtained at different densities of the sand base based on the results of laboratory tests3 and the results of computer modeling, using the software systems "ANSYS" and "Plaxis 3D".It was found that for loose sandy soils, at densities of 1.48 – 1.53 g/cm
3, close to experimental values of the deformation modulus were obtained using a three-dimensional finite-element model of polylinear isotropic hardening "PLAS (Miso)," in the program "ANSYS." For average density bases at ρ = 1.55 – 1.66 g/cm3 minimum differences between experimental and numerical values were obtained using the «Plaxis 3D» complex.
Intelligent buildings for energy consumption management
Authors: Bucur I , Axinte P , Pleşcan C , Şerban A
Published: April 2021

The main concern of the paper is the energy consumption management, in relation to the advantages and disadvantages of an intelligent building. The building sector consumes about one third of primary energy. An intelligent use of energy could have an impact on the energy consumption and cost. Energy management is the process of controlling, conserving and monitoring the energy in a building or recently in a home. With the use of sensors, all systems are connected and useful data is gathered to improve the building’s efficiency. Intelligent building design is the future of building and building services sector. Enhancing energy preservation strategies and using sustainable design approaches are necessary in developing intelligent buildings. This implies a more effective approach to reaching the green goals, and it also implies financial savings. Building an intelligent building involves a larger investment, but in the long run the usual expenses will decrease. National grid energy consumption will decrease with the use of renewable energy sources, such as solar or wind energy, if the energy is produced on site. In order to make a difference in the climate change, intelligent buildings depend on the non-fossil sources, which will affect the energy usage. Furthermore, an intelligent building will increase the comfort and productivity of its occupants, for either a workspace or a home.
Renewable energy sources potential evaluation in Romania
Authors: Bucur I , Axinte P , Plescan C , Şerban A
Published: April 2021

Renewable energy sources (wind energy, solar energy, energy hydropower, ocean energy, geothermal energy, biomass and biofuels) are alternatives to conventional fuels in the greenhouse gases emissions reduction process. Because of the EU legislation support, the renewable energy sources have evolved significantly in recent years and in 2009 EU set a target of 20% energy consumption comes from renewable energy sources by 2020. In 2018, the target has been set for 32% of energy consumption from renewable energy sources by 2030. There is currently a debate on the policy framework future for the period after 2030. Greenhouse gas emissions is considered a serious threat regarding climate change, with potentially disastrous effects on humanity. The use renewable energy sources (RES), together with improved energy efficiency, can contribute to the reduction of energy consumption, the reduction of greenhouse gas emissions and, consequently, to prevent dangerous climate change. The potential of biomass, solar, hydro, wind and geothermal energy is very important, especially in recent years, due to financial support mechanisms such as green certificates, which in many European countries helped this sector to developed progressively.
Investigation of HGHE near building basement – a case study
Authors: Bulmez A M , Ciofoaia V , Boian I
Published: April 2021

Ground heat exchangers represent the barrier between installing a ground source heat pump (GSHP) or a heat pump that use another source as water or air. While the vertical ground heat exchangers (VGHE) yield better results than horizontal ground heat exchangers (HGHE), the installation cost is higher than HGHE. Although, HGHE installation cost is a lot more affordable for residential use, it has the disadvantage of requiring a large installation area and lower efficiency than VGHE due to the temperature variation at the surface of the ground throughout the year. This study focuses on investigating possible use of the energy that is lost through the ground from basements in general, to help the heat pump when the HGHE is installed in the proximity of the basement. In order to achieve concluding results, an experiment was conducted at the University of Transilvania from Braşov, at the Faculty of Civil Engineering. In the experiment the HGHE was installed next to the basement exterior wall. In addition, a CFD numerical study was conducted. Firstly, to verify the experimental measurements and secondly, to obtain results with different working parameters. The results indicate that the thermal insulation degree of the basement wall and floor is an important parameter when considering heat loss into the ground. Likewise, the thermal state of the basement, heated or unheated, contributes considerably to the final results. Consequently, positioning the HGHE in the proximity of basements can represent an energetic optimization, especially when the basement is heated and it isn’t thermal insulated, as can be the case for an existing building.
Flood frequency analysis of Casimcea river
Authors: Cerneagă C , Maftei C
Published: April 2021

Flood frequency analysis is the most important statistical technique in understanding the nature and magnitude of high discharge in a river. This technique is used for establishing a relationship between flood magnitude and frequency of occurrence (return period). This study performs the flood frequency analysis of Casimcea river. The Casimcea catchment is located in the Dobrogea-Littoral basin of south-eastern Romania, and covers parts of two counties, Tulcea and Constanta. The main river of Casimcea catchment flows into the Tasaul lake and has two main tributaries (Ramnic and Cartal). In this study, Log-Normal, Log-Pearson Type III and Gumbel probability distributions have been applied on maximum discharge time series data of four hydrological stations, Casimcea and Cheia on Casimcea River and Pantelimonu on its main tributaries Ramnic and Cartal. For this study have been used the annual maximum series data spreading from 29 to 52 years. The frequency analysis will be performed with Hydrognomon. open-source software for the analysis of hydrological data. Hydrognomon is free software licensed under the General Public License (GPLv3).
The influence of materials on the behaviour of joints with multiple bar connections
Authors: Heinemann P , Isopescu D N , Maxineasa S G
Published: April 2021

Joints made out of tubular steel members are often used in industrial constructions, like offshore, trusses or tree-shaped columns. The joint area is the weakest point in a truss structure. Beside the normal static behaviour many non-linearities due to the geometry or to the welding process have to be taken into account. Steel hollow sections are often used. Much research was made on welded nodes so far. To increase the resistance of a joint it is an option to vary the material choice. Many variations were tested in the past. It is possible to change the overall material of a joint or using composite structures, like a concrete filled column. Or the steel of the welding line can get an additional material component. Another aspect is to reinforce the joint for example by a stiffened ring. In this paper a state-of-the-art review of the influence of different materials to the resistance of welded nodes is given.
Thermo-energetic assessment of industrial buildings
Authors: Iancu I E , Moga L
Published: April 2021

The present paper is focused on the assessment of industrial buildings from their thermal and energy performance perspective, driven by the need to reduce energy consumption and CO2 emissions on a worldwide level. A state of the art will be elaborated regarding the environmental impact of buildings that led to an increased pressure on a more energy efficient design. The focus will afterwards turn on the constructive solutions of industrial buildings for a better understanding of their elements and materials used. Aspects regarding the national and international stock of industrial and logistics spaces, demand, price range and future evolution of this sector, are also presented. Description and comparison is conducted on the building envelope thermal performance and its impact on the energy performance of buildings. Several conclusions will be drawn based on the obtained energy indexes and future research paths will be suggested.
Spalling of high strength concrete in fire
Authors: Lalu O , Darmon R , Lennon T
Published: April 2021

This paper reviews a series of experimental tests programmes undertaken at BRE in the UK on the performance in fire of high strength concrete with a particular focus on mix design to assess the effects of spalling. The experiments include a series of fire tests on reinforced and unreinforced concrete columns and tunnel linings. The paper will provide information on the parameters that lead to explosive spalling of tunnel linings in a fire situation and on the measures available to mitigate this hazard.
Static and dynamic plate loading tests of stabilized soil samples used for riverbank consolidation
Authors: Nagy A-Cs , Ilieş N M , Cîrcu A-P , Ciubotaru V-C , Crăciunescu B M
Published: April 2021

Building of an experimental slope protection system on Căpuş river, near Cluj presented the opportunity of in situ testing of stabilized soils. Different hydraulic binder was used on each side of the river, so this testing series provided valuable data about deformability properties of the encountered soil types. There are some deformability parameters used in Romania which were “imported” at the specific request of foreign investors. The strain modulus, Ev, is a parameter expressing the deformation characteristics of a soil and is calculated taking values from the load-settlement curve obtained from the first and second loading cycle, on a static plate load test. In earthworks, the dynamic plate load test using the Light Falling Weight Deflectometer may be used for testing load-bearing capacity as an alternative to the static plate load test which provides the strain modulus, Ev parameter. Dynamic modulus of deformation Evd is a parameter for the deformability of soil under a defined, vertical impact load with the impact duration. Its value is being calculated with the maximum settlement of the load plate. None of these methods made way into official Romanian standardisation, the Evd is subject of a technical agreement, which also contains the correlation of it with Ev. Conducting both static and dynamic loading tests enabled the verification of validity of relation between strain modulus and dynamic modulus.