bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of the effect of nose shape and geometry at supersonic speeds for missile performance optimisation
Authors: Kim B K , Al-Obaidi A S M 
Published: July 2023

Abstract
This paper investigated and analysed the influence of the missile nose shapes and geometry on the drag force coefficients at supersonic Mach numbers ranging from 2 to 5. The nose shape investigation includes a pointed cone, pointed ogive, and blunt cone with a constant length and diameter of cylindrical afterbody. Subsequently, the nose length was manipulated to investigate how the nose geometry with different fineness ratios affected each drag component. The drag force coefficient and its components were determined using a program called MATLAB_Aerody, in which a semi-empirical approach was implemented for the calculations. The program was validated against the semi-empirical results with existing theoretical and experimental results. The comparison showed a maximum error of 3.6%. The results of the nose shape analysis show that a sharper and more slender nose with a pointy tip produces a minimal drag. Nose bluntness, however, creates considerable additional drag force due to a higher wave drag coefficient by forming detached or bow shock waves. At supersonic speeds, increasing the fineness ratio significantly reduces the drag force by drastically decreasing the wave drag coefficient with a marginal increase in the skin friction coefficients. However, the results show an insignificant additional gain for the skin friction drag and a reduction in the wave drag coefficient when the nose has a fineness ratio beyond 4.5. Furthermore, the results from both analyses show that the base drag coefficient is invariant with the nose shape and the fineness ratio. Therefore, a better missile performance can be achieved with a sharper and more slender nose shape with a higher fineness ratio.
Fabrication of hydrogel controlled-released Phosphorus encapsulated in starch-polyvinyl alcohol film
Authors: Selapa Sivashanggary , Phang Siew Wei , Shuib Anis Suhaila , Tee Jen Looi 
Published: July 2023

Abstract
Traditional soluble phosphorous(P) fertilizers can easily leach into water systems causing water eutrophication, a major environmental problem caused by an excess release of nutrients. Controlling the release of P in response to the plant demand could reduce fertilizer’s losses and also reduce environmental pollution. This study establishes a concept of controlled release fertilizer, in which a hydrogel fertilizer film is fabricated by incorporating starch, polyvinyl alcohol and ammonium dihydrogen phosphate fertilizer which tend to immobilize the release of phosphate ions and accelerate responsively their release rate in the presence of water. The experiment aims to study the effect of incorporating Starch, and Polyvinyl alcohol (PVA) to Ammonium Dihydrogen Phosphate fertilizer by varying the composition of PVA-Starch-Ammonium Dihydrogen Phosphate and preparing the films through solution casting method. FTIR is being used to investigate the effect of Starch, PVA, and Ammonium Dihydrogen Phosphate composition on the intermolecular bonding of the fabricated film. A total of 10 samples with different material composition is prepared and the intermolecular bonding between this composition is being compared with that of pure starch, pure PVA and pure Ammonium dihydrogen phosphate fertilizer. The FTIR peak will reveal evidence of hydrogen bonding between phosphate molecules and the functional group of polymer molecules as well as showed all the characteristics band of Starch, PVA and Ammonium Dihydrogen Phosphate. The varying formulation of film corresponded to varying intensity of peak and also stretching vibrations.
Automated Parcel Loading-Unloading Mechanism Design for Delivery UAV
Authors: Eu Kwok Quan , Phang Swee King 
Published: July 2023

AbstractUnmanned Aerial Vehicle or UAV has evolved rapidly because of improved regulations and advancement in technology. During the COVID-19 pandemic, delivery UAVs were utilized more often than ever to deliver medical supplies, as well as parcels. Delivery UAVs work by collecting the goods and keeping it in a designated holder, which it then navigates through an area and dropping it off at the receiving point. The main factors that are considered for the design of a delivery UAV mechanism includes size and weight of parcels, security and the efficiency of loading and unloading parcels. The drop-box mechanism takes in the factors contributing to existing delivery UAV mechanisms and provides a solution that can overcome most of these concerns. The mechanism was designed through SOLIDWORKS software and 3D-printed. With the help of SOLIDWORKS, an analysis was performed, and it was concluded that the mechanism could handle a maximum of 2kg. Aside from that, the mechanism drops off parcels automatically and encourages contactless delivery.
A study on transfer function to estimate the central aortic blood pressure waveform
Authors: Leonard Batende Vwikalo , Sooriamoorthy Denesh 
Published: July 2023

Abstract
Noninvasive measurement of the central aortic blood pressure has become an important technique that has generated a lot of interest around the medicine industry because it can estimate the central aortic blood pressure waveform without inserting a pressure-sensing catheter into the ascending aorta. The accuracy of noninvasive estimation of aortic hemodynamics and cardiac contractility is still debatable in noninvasive measurement of the central aortic blood methods. The objective of this project is to investigate the transfer functions available for converting radial blood pressure waveforms to central aortic blood pressure waveforms. In this project, three different transfer functions will be investigated which are The Generalized Transfer Function, N-Point Moving Average and Adaptive Transfer Function in order to recommend the effective method in terms of accuracy. The study methodology will be conducted through the software MATLAB R2021b. The investigation of these three methods will be conducted with data collected from virtual subjects from the HaeMod database. The Generalized transfer function, N-Point Moving Average and Adaptive Transfer Function will be coded, evaluated, and analyzed as part of the methodology. The determination of the most effective method among the three transfer functions will be attributed according to output comparison of Systolic peak differences, the RMSE and the MAPE between the estimated central aortic blood pressure and the measured central aortic blood pressure.
New Dynamic Time-of-Use Tariff For Islanded Microgrid System With High Penetration of Renewable Energy
Authors: Nazar J. , Jamian J.J. , Baharudin M.A. , Syed Nasir S.N. 
Published: July 2023

Abstract
This paper proposes a dynamic time-of-use (d-TOU) tariff scheme for microgrid (MG) systems in islanded mode. The main problem for the islanded MG is the high cost of electricity, and the output from renewable energy is uncontrollable compared to the traditional grid. Therefore, this paper focuses on developing a suitable tariff scheme that provides reliability and financial benefits for both utility and customer. The time zone energy prices based on the Levelized Cost of Energy (LCOE) are introduced for islanded MG. The results show a contradiction between islanded MG with the standard traditional power generation TOU. Even though the LCOE obtained for MG is higher than conventional electricity rates, the greenhouse gas (GHG) emissions rate is reduced by 85%. In conclusion, the proposed d-TOU tariff scheme is suitable for the islanded MG system and it is beneficial for both the utility and the customer by not causing a financial burden to the utility and encouraging the customer to make a demand response in the future.
A Wheeled Mobile Robot Obstacles Avoidance for Navigation Control in a Static and Dynamic Environments
Authors: Sariff Nohaidda , Xing Bryan Tan Shun 
Published: July 2023

Abstract
This research focuses on the performance of the obstacle avoidance feature implemented on a wheeled mobile robot by using Sugeno Fuzzy Inference System (FIS). The test was done using a simulation software Webots and the layout was first draft out using walls, floors, and objects in order to set a boundary and obstacles for the simulation. To test the effectiveness and efficiency in terms of time and distance, the simulation time and trajectory of the Khepera implementing the Sugeno FIS was recorded and compared with the Khepera without implementing the Sugeno FIS. The inputs of the ultrasonic sensors were also recorded in order to analyze whether if the Khepera detects incoming objects or if Khepera follows the rules set in the algorithm.
Design and Control of Autonomous Rover for Foliage Navigation
Authors: Chow Kin Long , Phang Swee King 
Published: July 2023

Abstract
Implementation of UGV in civilian applications is getting trendy and normalized due to its solid achievement in executing mission under harsh environments. The UGV foliage environment-oriented applications even attracted the people’s attention in correspond sectors to ease their tasks with guaranteed performance. Given this, the development of the autonomous rover from sensors and control aspects with the consideration of foliage environment interest people to enhance its functionality. To ensure the sensor is not easily affected by the environment factor, the radar and the camera are selected to provide the environment perception to the rover. The approach for a linear Proportional-Derivative (PD) controller with the dynamic modelling of the UGV is also discussed in this paper. The study shows preliminary results that are working.
HAp-Ti-6Al-4V Interface Fretting Wear Failure Prediction in Different Bio-lubricants using FEM
Authors: Yi Teoh Zhi , Nagentrau M. 
Published: July 2023

Abstract
Plasma-sprayed hydroxyapatite (HAp) coated titanium alloy (Ti-6Al-4V) has been widely used as the material for artificial hip implants. However, studies have greatly challenged their long-time usage due to fretting wear behavior at the HAp-Ti-6Al-4V interface. Wear particles from the HAp coating may activate inflammation at surrounding organs, further leading to implant loosening, implant failures and even total hip replacement (THR) revision surgeries. Hence, present research aims to adopt the finite element methodology (FEM) in predicting fretting wear failure at the HAp-Ti-6Al-4V interface of uncemented hip implant femoral stem component under different body environments (bio-lubricants). A finite element (FE) model based on the half-cylinder on flat contact configuration subjected to actual mechanical and tribological properties under different bio-lubricants is developed with the modified Archard wear equation adopted to examine the fretting wear behavior through simulations. A parametric study is then conducted to evaluate the combined effects of different mechanical and tribological properties, including HAp coating thickness, bone elastic modulus and loading condition, under different bio-lubricants on the fretting wear behavior of HAp-Ti-6Al-4V interface. Lastly, single and multiple regression analyses are performed to formulate fretting wear predictive equation that acts as a fast-fretting wear failure prediction tool. The FE predicted results in this paper prove that the maximum wear depth at HAp-Ti-6Al-4V interface is promoted under lower coefficient of friction (COF), smaller HAp coating thickness, smaller bone elastic modulus and larger intensity of fatigue loading. The formulated predictive equations suggest a strong correlation between independent and dependent variables due to R-squared (R2) values being larger than 0.75 which guarantee goodness of fit.
The effects of different plant species in greenwall filtration system on lakewater treatment
Authors: Chan Nicole Yoong Xin , Tee Lee Hong , Oh Kai Siang , Lam Weng Hoong , Yoon Li Wan , Phang Eunice Siew Wei 
Published: July 2023

Abstract
It is a concern when 90% of Malaysia’s water supply comes from lakes that hold moderate to bad water quality status. Greenwalls are a sustainable modern-day filtration system that proves to be a solution in tackling this lakewater quality issue. To date, there are still questions unanswered regarding the treatment performance of the greenwall filtration system used for lakewater treatment as most research conducted is related to greywater treatment in terms of water quality. Thus, this research aims to investigate the effects of different plant species, filter media ratio and lakewater flowrate on the lakewater treatment performance in a greenwall filtration system. In this work. the plant species between Epipremnum aureum and Mentha piperita as well as the filter media ratio of coir to perlite between 3:1, 1:1 and 1:3, the lakewater flowrate between 15 L/h, 30 L/h and 160 L/h with the highest treatment efficiency for lakewater was investigated and chosen. First, experimental work was conducted with a constant plant species which was Epipremnum aureum and a constant filter media ratio of 1:1 (coir:perlite) to filter lakewater at different flowrates of 15 L/h, 30 L/h and 160 L/h where the initial and final sample of the lakewater was collected. The system ran for 3 hours each time and is referred to as a cycle. The COD and pH of the lakewater were tested before and after each cycle to compare the water quality. This study aims to justify and determine how different plant species as well as the filter media ratio and lakewater flowrate affect the lakewater treatment performance. The results show that Mentha piperita with fibrous root type, filter media ratio of 3:1 of coir to perlite and lakewater flowrate of 30 L/h provide the greatest removal efficiency of pollutants from lakewater. Ultimately, this study will contribute to the ever-growing research of greenwall filtration system for lakewater treatment making this treatment method more feasible for future commercial applications.
Study of refrigerant flow consistency and tolerance control of a distributor for air conditioner
Authors: Chew Eushayne , Al-Obaidi Abdulkareem Sh Mahdi , Chng Ming Hui 
Published: July 2023

Abstract
In the residential air-conditioning system, a refrigerant distributor is a device that connects the outlet of an expansion valve to each evaporator coil circuit when paired with a multi-circuit evaporator. The efficiency of the heat exchanger is significantly impacted by the two-phase refrigerant’s distribution. Only when the distributor has consistent performance can the heat exchanger be utilized efficiently. Hence, the aim of this study is to identify the impact of manufacturing tolerance of the distributor for air conditioner on the flow consistency. Preliminary analysis for different rules of factors such as the installation angle, barrel diameter and branching angle are studied through Computational Fluid Dynamics (CFD) simulation to analyze the parameter sensitivity. Based on the mean value of the standard deviation of the mass flow rate and quality at each path, the distributor’s performance is evaluated. It is found that the tolerance control on barrel diameter and installation angle will give significant impact on the flow performance, this is because the evaluation of standard deviation for mass flow rate and quality for these conditions are above average, that are 0.443 and 0.0161 respectively. On the contrary, a minimal influence is seen when the branching angle can be controlled within 1 degree tolerance. The following parameters’ effect on flow consistency are presented in order of largest to smallest: barrel diameter, installation angle and branch angle. A thorough study on the performance for the existing distributor is conducted and the tolerance of the important geometrical parameters (i.e., barrel diameter and branch angle) and working condition (i.e., installation angle) are identified.
Investigation of the Effect of the Wind Speed on the Aerodynamic and Architectural Design of Tall Buildings
Authors: Hui Yong Win , Al-Obaidi Abdulkareem Sh. Mahdi , Mari Tamil Salvi , Gunasagaran Sujatavani , Ching Michael 
Published: July 2023

Abstract
The magnitude, speed, direction, and distribution of the wind are known to have a negative impact on high-rise buildings, particularly when the building is extremely tall. As the height of the building increases, the effect of the wind increases significantly. This results in a high wind pressure exerted on the building which causes the wind loads subjected by the buildings to increase considerably. Thus, this study investigates the wind effect on tall buildings and proposes a solution to reduce the aerodynamic drag through a design that meets both architectural and aerodynamic considerations. Investigation of wind effect on tall buildings with different wind speeds, heights and shapes is carried out. Numerical methods are utilized to study the wind pressure, drag coefficient and pressure distribution on different types of buildings. ANSYS Fluent is used for computational fluid dynamics (CFD) simulation to assess the drag coefficient of the buildings. The drag coefficient of the building is determined in Reynold’s number range of 1×106 to 2×106. The study is conducted in low subsonic speed (Ma < 0.3). The result shows that the drag coefficient of the building tends to be constant at low subsonic speeds. Besides, the study found that the drag coefficient increases by 1% to 3% for every 0.1 m increment in the height of the building. The study also found that a cylindrical building has the lowest drag coefficient because of its more streamlined shape. Overall, this study provided guidance and recommendations for wind resistance which can be taken into consideration when designing tall buildings. Hence, the building can be built even taller while maintaining its rigidity and stability.
The effect of air velocity and indoor ambient properties on the effective operating range of an air ionizer device
Authors: Karim H , Nagentrau M , Ling K J N H , Chin W M 
Published: July 2023

Abstract
Air ionizers are devices that purify the indoor air by artificially generating negative air ions (NAIs) which are proven to improve air quality and well-being of humans. Hence, more ionizers are being incorporated into heating, ventilation and air conditioning (HVAC) applications nowadays. . Every ionizer has its effective range of operation, which is the area inside a room that can potentially be covered by significant concentration of NAIs compared to the general concentration of ions naturally present in the room. This range may change depending on the indoor temperature, humidity and fan speed of the HVAC unit as preferred by the room occupants. Present research intends to design an experimental setup that could measure negative air ion (NAI) concentration at varying distances from an ionizer under different values of the aforementioned parameters. The experiment was conducted inside an indoor psychrometric test room to allow controlling of ambient temperature and humidity. Air velocity through the ionizer was varied from 1.5 m/s to 4.5 m/s, whereas the range of temperature and relative humidity were set from 25°C to 31°C and 60% to 80% respectively. To evaluate the ionizer’s operating range, NAI concentration was measured at every preset longitudinal (0 cm to 75 cm), lateral (-25 cm to 25 cm) and elevation (-15 cm to 15 cm) distance relative to the ionizer for 6 minutes using an ion counter named “Air Ion Counter Model AIC2”. The results reveal that the ionizer’s effective operating range increased with velocity, with the furthest range recorded at 4.5 m/s. Whereas a negative correlation was found between the ionizer’s effective operating range with temperature and humidity, with the furthest range recorded at 25°C and 60% respectively. The results also show that most ions were distributed in areas below and towards the right side from the ionizer’s perspective.
Numerical Analysis of Delamination of High-Performance Concrete (HPC) Strengthened Reinforced Concrete (RC) Beam
Authors: Wong Jehoshaphat C.Q , Nagentrau M. , Mansor S.H. 
Published: July 2023

Abstract
This study investigates the numerical analysis of delamination behavior of high-performance concrete (HPC) strengthened reinforced concrete (RC) cantilever T-beam by using finite element method. A length of 1000 mm reinforced concrete cantilever T-beam and height of 1600 mm reinforced concrete column will be created. Besides that, the truss members such as the stirrups and the rebars will also be added into the structure as a reinforcement. The HPC layer will be assigned on the top of the cantilever T-beam as a coating material. The study is to investigate the influences on the delamination behavior when the thickness, width, and coefficient of friction of the HPC layer has been applied on the model as a coating material. Finite element model (FEM) will need to be created and justified in ABAQUS software before applying the parameters for analysis. Limited studies had been conducted on the delamination behavior of using HPC layer as a strengthening mechanism and analyze the output such as the COPEN and SDEG. Based on the results extracted from the software, the delamination behavior can be observed and analyzed and investigate the influence of difference parameter has been assigned. Therefore, this research paper will analyze the influence of the layer thickness, width of the layer, and the coefficient of friction between the substrate and the layer.
On the locating rainbow connection number of amalgamation of complete graphs
Authors: Bustan A W , Salman A N M , Putri P E 
Published: July 2023

AbstractLocating rainbow connection number determines the minimum number of colors connecting any two vertices of a graph with a rainbow vertex path and also verifies that the given colors produce a different rainbow code for each vertex. Locating rainbow connection number of graphs is a new mathematical concept, especially in graph theory, which combines the concepts of the rainbow vertex coloring and the partition dimension. In this paper, we determine the locating rainbow connection number of amalgamation of complete graphs.
Coefficient estimation of simultaneous equations in the case of stochasticity of exogenous variables
Authors: Minitaeva A M 
Published: July 2023

Abstract
The paper deals with the question of obtaining such an estimate of the parameters of the model of simultaneous equations, which would have better statistical properties in comparison with the estimates of both the usual method of least squares and two-, three-step methods of least squares, as well as the method of fixed point and other methods of evaluating the coefficients of the equations considered in the system simultaneously. The main drawback of methods based on minimization of the sum of squares of deviations of real observations from some theoretical dependence is that the sum of squares of errors that correlate with the values of variables included in the expression for these errors is minimized. A violation of the basic assumption of least-squares methods about the independence of predetermined variables and errors leads to the fact that least-squares estimation methods in this case lose their best properties: unbiasedness, efficiency, and consistency. The paper proves the theorem about the efficiency of estimates obtained using two-step least squares methods and that of estimates obtained using the method of factorization of simultaneous equations.