bluuebunny/crossref_metadata_2025 huggingface dataset:
Techno-economic analysis in application of glass solar cell on storey building: A case study of office building
Authors: Fadli H , Dalimi R
Published: March 2021

Urban area populated by edifice and storey building can complicate process of electric energy distribution to the middle of city. Citizen reluctance if their settlement passed by transmission network or being built substation, and bigger cost of underground cable than overhead line increases such difficulty level. If there is problem in delivering electric energy, so the city will face electric energy crisis and disrupt society life. One of solution in overcoming that issue is by installation the glass solar cell (transparent solar cell) with thin film material (CdTe) on storey building, which located in the middle of city and its electric energy supplied by PLN. In this study, glass solar cell will be installed in existing building “W” with solar cell area about 6,916 m2. Glass transparency level of study object building is 30%, so by installing same transparency level of solar cell can supply maximum electric energy 897,184 kWh/year or equal to 35% electric energy demand of building. Economic feasibility analysis applied in this study, where NPV is IDR 398,961,738, IRR is 7.47% and the payback period is 11 years, so this technology is feasible to be implemented economically. If considering the tilt and azimuth angle of solar cell installation, instalment in B and C side of building generates smaller electric energy than A and D side. This condition caused by bigger reduction on solar irradiation energy that accepted by B and C site, namely 66.35% for B side and 67.22% for C side. The usage of glass solar cell contributes to deduct greenhouse gas emission, maximum 732,999 kg/year.
The use of edge cut on microstrip antenna patch with the modified partial ground plane for bandwidth enhancement
Authors: Fernandez R , Ra’id F , Andre H , Baharuddin  , Firdaus
Published: March 2021

This research proposes the use of edge cut on the antenna patch with a modified partial ground plane to overcome the inherent characteristic of the microstrip antenna, which is narrowband. The antenna has to cover all of the LTE frequency bands, which is from 0.824 – 2.4 GHz. FR4 epoxy with a dielectric constant of 4.4 and a thickness of 1.67 mm is used as a substrate for the antenna. The proposed antenna is simulated by an EM Simulator. The simulated results show that the return loss of -18.82 dB and the VSWR of 1.25. These parameters confirms that the antenna is well-matched along with the LTE bands. This wideband antenna has a directional radiation pattern with a maximum gain of 4.65 dB.
A Circular Patch Microstrip Antenna with Partial Ground Plane for WiMAX and WLAN Applications
Authors: Fernandez R , Putra T , Andre H , Firdaus
Published: March 2021

Narrow bandwidth is the main problem of a microstrip antenna. Enhanced bandwidth is done by applying a partial ground plane. The antenna patch layer is a circular formed based on the formula to obtain its initial dimension. The dimension is used as a base for the antenna design with ground plane reduction. The antenna is designed using FR4, which has a thickness of 1.6 mm with a dielectric constant of 4.3. Simulation results from the design of partial ground plane antennas on WiMAX and WLAN band frequencies showed an increase in bandwidth of 3.14 GHz with minimum return loss values of -17.01 dB, gain antenna of 1.32 dB and a directional radiation pattern.
Design analysis of solar panel structure LAPAN-Constellation Satellite using finite element method
Authors: Ramayanti S , Budiantoro P
Published: March 2021

Satellite Technology Center (Pusteksat) of LAPAN currently develops a satellite constellation with communication mission. This satellite will implement a deployable solar array to perform its missions. The objective of this research is to find solar panel structure with natural frequency in accordance with the requirements of the launcher and have the minimum mass. This method starts by determining the requirement of solar panel structure and then designing the solar panel into three models as follow: solar panel structure with solid aluminium sheet model, isogrid and orthogrid model, and honeycomb model. The material used for solar panel structure for aluminium sheet and isogrid and orthogrid model is Al 7075-T6 because the material is light in weight and has a high stiffness to withstand loading conditions. Meanwhile, for solar panel structure honeycomb use aluminium alloy 5052 for both face and core follow the previous satellite. The next step is analyzing the natural frequency of three models solar panel structure with modal analysis. This study shows that solar panel with honeycomb model give the best option as a solar panel structure on a constellation satellite. From the result, it can also predict the modal shapes that can be used as a place to lay the accelerometer when testing and measuring natural frequency on vibration test machines.
Solid Waste Management System Model of Village Tourism Area of Nagari Tuo Pariangan, Indonesia
Authors: Aziz R , Ruslinda Y , Yeni Y S , Dewilda Y
Published: March 2021

NagariTuoParianganis one of the three leading tourist attractions in Tanah Datar Regency. The increase of tourists visits NagariTuoPariangan Area has resulted in increased waste generation, improperly managed existing solid waste management endanger the environment, and sustainable development. This study aims to develop a solid waste management system model of NagariTuoPariangan as an effort to preserve the environment and support tourism development. The generation of solid waste of this area was 786,803 kg/day, with the largest were food waste as 35% and plastic waste of 32% of total waste. The solid waste management system model considers three categories of sorting types (compostable, recyclable, and residue), while the storage use of individual type (trash bags and bin) and communal (bin 40 L, 6 m3 containers). The collection system uses a 1.5 m3 motorized pedicab. The processing method applies composting, enumerating plastic waste, selling paper, and metal waste to the collectors. Moreover, the residue transport using a 6 m3 arm roll truck from the recycling center (TPS 3R) to Bukit Sangkiang Landfill. Meanwhile, the non-technical aspects planned for regulation on waste management by WaliNagari, the formation of Non-Governmental Organizations, adjusting funding according to applicable regulations, and increasing the participation of traders, communities, and visitors.
Defect analysis on PVC pipe using Statistical Quality Control (SQC) approach to reduce defects (Case Study: PT. XYZ)
Authors: Ginting R , Supriadi S
Published: March 2021

Product quality is an important factor affecting the level of development and progress of a company. Statistic Quality Control (SQC) as a quality control tool for production can help companies whether the products produced are still under control or not from the initial process or the final product. The research was conducted at PT. XYZ to find out the causes of defects that occur in the PVC pipe production process. In the research, it is known that the defects that occur are melt, crack and hollow with the majority of defects that occur are melt and crack. By using a Cause and Effect diagram, it is known that the cause of defects occurs due to human, machine, materials and method factors. Solutions for defects that occur are given in the hope that the company will implement the solutions offered to reduce the number of defects that occur in the production process.
Production Scheduling Optimization to Minimize Makespan and the Number of Machines with Mixed Integer Linear Programming
Authors: Farizal F , Gabriel D S , Rachman A , Rinaldi I
Published: March 2021

In production management field, production efficiency can be improved through minimizing machine downtime, optimizing production scheduling, minimizing inventory of raw materials and finished products. In this research, the production efficiency is improved through optimizing production schedule that has two goals; not only minimizing production makespan but also minimizing the number of machines used. For the purpose, a mixed integer linear programming (MILP) model was developed. The model was used to solve a problem producing 6 products with 4 production lines. In this study, product demand was first forecasted with Autoregressive Integrated Moving Average (ARIMA) method. Optimization results comes up with makespan of 295.4 hours using only one production line. As addition, this research is also dealing with three real life production scenarios.
Effect of rock sugar as a pore-forming material on the physical and mechanical properties of hydroxyapatite scaffold
Authors: Indra A , Hadi F , Mulyadi I H , Affi J , Gunawarman
Published: March 2021

Hydroxyapatite (HA) ceramic scaffold had been made using the pressureless sintering method for bone scaffold applications. Micron- and nano-sized HA as the primary material with the addition of polyvinyl alcohol (PVA) as a binder and rock sugar (RS) sized 298-420 μm as pore-forming material had been prepared. RS was applied to produce interconnecting pores in the HA scaffold. The green body was made by uniaxial pressing method at a pressure of 200 MPa. Preheating was carried out at a temperature of 700°C with a holding time of 1 h, aimed at eliminating PVA and RS, and then the temperature was increased to 1200°C with a holding time of 2 h. During the sintering process, the heating rate and cooling rate were maintained at 3°C/min. Physical and mechanical properties were tested respectively, including porosity and compressive strength testing. The results showed that the 23.0% porosity obtained a compressive strength value of 15.6 MPa at a ratio of HA:RS of 65:35 wt%. The highest porosity of 48.4% was obtained with a compressive strength of 4.9 MPa at a ratio of 55:45 wt%. In this study, the maximum addition of RS was only at 45 wt%, while the addition of RS reaching 50 wt% or more could affect the tangential bonding between HA powders during the sintering process.
Lift Study of a Flapping MAV Wing Design Based on Bat Wings
Authors: Suhaimi S , Shuib S , Kadarman A H , Yusoff H
Published: March 2021

Bio-inspiration is a design ideation method that uses observations found in nature to solve a mechanical problem. In this study, a simulation study of a micro air vehicle (MAV) wing design that is based on bat wings was done and validated experimentally. The wing model was generated using an in vivo observation where the margin wing shape was traced and then used to generate a flat wing with a margin shape of a batwing. The lift of the wing was studied at 4m/s wind speed with a flapping angle of 55°, and at the angle of attack from 0° to 35°. The simulation was done using ANSYS V1.6 software and the experimental study was done using an open circuit subsonic wind tunnel. It was observed that the wing has a stall angle of 25° and a CLmax of 3.2. The result also shows that the difference between the simulation and the observation result to be small with 0.2% at the smallest point and 5% at the largest point. This shows that the simulation model was valid and can be used for future wing design.
Crack Analysis on Ti-6Al-4V ELI Coated with Commercial Hydroxyapatite for Implant Material: Literature Review
Authors: Ardhy S , Gunawarman  , Affi J , Yetri Y
Published: March 2021

Ti-6Al-4V Extra Low Intertitial (ELI), a type of titanium alloy that is commonly used for implant material. However, use of Ti-6Al-4V ELI still has some problems. The main one is oxide layer on the surface can be detached during application due to corrosion process. Such corrosion debris is a toxic substance to the human body. It is, therefore, necessary to modify the surface of the implant to avoid corrosion process by using coating method. A good coating material for orthopedic implants comes from ceramics, namely hydroxyapatite (HA). However, there are also an obstacle, HA coating on titanium, sometimes not evenly across the surface, causing cracks on the coating layer surface. There are two methods that are often used in coating materials, namely Electrophoretic Deposition (EPD) and Dip Coating. This study analyzed number of literatures using a searching engine of international reputable journals Science Direct, Pubmed on biomaterials and biomedicine fields using the keywords of Ti-6Al-4V ELI, hydroxyapatite, cracks, EPD method and Dip Coating. This literature review may useful for the readers and researchers, in order to choose the best method for crack reduction in the coated implants. Dip Coating method is better than EPD method in point of view simplicity and cost. Moreover, the coating layer is evenly distributed, no build-up of HA in several surface areas, so that cracks on surface are minimized.
Comparison of Physical and Mechanical Properties of Antifouling PVDF Membranes by Titanium Dioxide and PES Membrane by Titanium Dioxide
Authors: Mataram A , Nukman  , Nasution J D , Riadi M I , Pataras M , Aditya B B , Septano G D , Anisya N , Nadiyah N A
Published: March 2021

The main factor to support daily life is water, but the fact is there are approximately 2.1 billion people currently threatened with a shortage of clean water. Polyethersulfone (PES) and Polyvinylidene Fluoride (PVDF) are polymers that are commonly used for membrane fabrication because they have extraordinary properties in the screening process. The addition of addictive substances into the membrane formation process is no less important as supporting the ability to be even better in membranes Titanium Dioxide (TiO2) as an additive with properties relevant to the two polymers which can cover the shortcomings of the two polymers. The printing process of PVDF and PES membranes with the addition of TiO2 uses a copper plate which is flowed with an electric field of 15000V DC. The results of the surface morphology of Scanning Electron Microscopy (SEM) both showed extraordinary changes compared without modification to the printing process as in previous studies. The tensile strength test results showed uniformity with the membrane morphology and an increase in the maximum stress value of the membrane to 3.86 MPa. Surface roughness values can help identify membrane impurity properties which are also relevant to the results of water treatment performance tests and contact angles. Finally, the process of forming membranes with the additional modification of the printing process can open new avenues to maximize water treatment performance and service life on the membrane.
An Improved Method for Dynamic Behaviour Prediction of Carbon Fibre Reinforced Epoxy (CFRE) using Finite Element Model Updating
Authors: Shah M A S A , Yunus M A , Rani M N A , Mirza W I I W I , Sani M. S. M.
Published: March 2021

The dynamic behaviour prediction scheme of carbon fibre composite structures are extremely challenging to be performed due to the geometrical ply-by-ply properties and the ply orientation issues. In this paper, a laminated carbon fibre reinforced epoxy plate with elastic and linear layers was used with aim to investigate the dynamic behaviour of the carbon fibre reinforced epoxy using practical modelling scheme via finite element modelling and updating method. A simplified FE model of the CFRE plate was developed using shell element properties known as PSHELL to represent geometrical laminated properties. Subsequently, the dynamic behaviour of the FE model was calculated using Nastran SOL103. Potential updating parameters of the FE model was analysed and identified using the sensitivity analysis. The model updating method was then used to update the initial FE model of the CFRE plate based on the experimental modal analysis (EMA) result. The comparison of the results were used in verifying the accuracy of the updated FE model of the CFRE plate. The result suggested that the PSHELL properties can be used efficiently to represent the geometrical laminated properties of the CFRE plate without considering the geometrical effect of ply-by-ply properties.
Effects of construction time on the performance of cement treated base
Authors: Win Maung A N , Lee Y P K , Ho N Y
Published: March 2021

Cement treated base (CTB) has been widely used as a stabilized base layer in pavement for highways, roads, airports, parking areas and some storage areas. CTB comprises mainly three components, namely, cement, water and either natural soil or aggregates. The mixture will become strong and durable after proper compaction and curing. CTB can be produced in central plant, haul to the laying area by dump trucks or can be mixed in-placed using proper materials and equipment. One of the key factors which can affect the performance of CTB is the construction time which consists of mixing to transportation, laying and compaction. This paper describes a study that was conducted to analyse the effects of construction time on the performance properties of CTB. Laboratory tests were conducted for various CTB mixtures. The CTB mixtures were compacted at different time frames and then tested for dry density and unconfined compressive strength. The results were then analysed to study the effects of construction time.
Evaluating the mechanical performance of asphalt mixtures in cyclic torsional shear test
Authors: Yokota S , Shibuya S , Lohani T N , Kamada O , Hisaro Y
Published: March 2021

In this paper, the mechanical performance of asphalt mixtures was examined in cyclic torsional shear test, in which the relationship between the averaged shear strain, γav, and the number of cyclic loading, N, was obtained by using a short, about 25mm height, specimen. In these tests, the effects of some influencing factors such as the type of asphalt mixture, the thickness of specimen and the temperature were examined. In each test, four indices; i.e., the slope of plastic flow line, the slope of stripping line, the number of load applications at the inflection point for stripping and the averaged shear strain at the inflection point for stripping, were defined for the relationship between γav and N. As a result of this study, we clarified that various performances such as rutting resistance, fatigue failure resistance and the stripping resistance of asphalt mixture can be appropriately evaluated by using the cyclic torsional shear test.
Prediction of unconfined compressive strength of cement stabilized pavement materials
Authors: Premarathne R P P K , Sawangsuriya A
Published: March 2021

This paper evaluated and justified suitable prediction equations for unconfined compressive strength (UCS) of cement stabilized pavement materials. Equations by multiple linear regression analysis were also proposed. Data including pavement recycling base and subbase layers were collected from the Bureau of Material, Analysis, and Inspection, Department of Highways, Thailand. Multiple linear regression was conducted using the SPSS software. Three equations obtained from multiple linear regression and past researches were compared. Two criteria were considered in the selection of equations in order to check the accuracy and precision of each equation. First criterion was based on the predicted UCS vs. actual UCS graph. The slope and interception values of each graph were evaluated. Second criterion used two indices: ranking distance (RD) and ranking index (RI). For a good correlation, both these indices shall approach zero. By considering the statistical analysis outputs from the two criteria, a relationship between UCS and California Bearing Ratio – water cement ratio [CBR/(w/c)] proposed by Sunitsakul in 2012 was justified as a suitable equation to predict the UCS of cement stabilized pavement materials. The study also confirmed that the relationship proposed by Sawangsuriya in 2016 for fine-grained soil with plasticity index was not appropriate for the prediction of UCS because the majority of the samples were non-plastic.
Sustainable pavement: A review on the usage of pavement as a mitigation strategy for UHI
Authors: Al-Humairi SFI , Alias AH , Haron NA , Hassim S , Mohd Jakarni F
Published: March 2021

Urban Heat Island (UHI) phenomenon is currently affecting many millions of people worldwide. The higher temperatures are experienced in urban areas as compared to the surrounding countryside. The UHI effect has been a great threat to human habitation, and the way to mitigate this problem has been a global concern over decades. Artificial and manmade pavements have been recognised as one of the major origins that deteriorate the thermal environments for living. On the one hand, commonly used pavement materials could lead to a reduced latent heat flux and an increased sensible heat flux to the environment. Following this, there is a series of experiments and numerical analysis that has been conducted by researchers. The selection of pavement type requires an understanding of a local context of an area and characteristics of the pavements. This current study emphasises on reviewing the features, factors and impacts of different type of pavements, as well as determining the suitability of different types of pavements. It is expected that the outcome from this study can assist in further understanding of pavements and its effects on UHI, as well as can ultimately assist in reducing the effect of UHI on human population.
Investigation on effects of aggregate roughness on bond strength of aggregate-bitumen systems
Authors: Mishra V , Singh D
Published: March 2021

It is critical to understand bonding-behavior of aggregate with bitumen. The surface chemistry and roughness of aggregates play an important role to create sufficient bond with bitumen. Usually, asphalt-bond-strength (ABS) test is used to directly quantify bonding-behavior of aggregate-bitumen system, further, surface-free-energy (SFE) approach has also been used by some researchers. AASHTO T-361 recommends to use aggregates polished with 280-silicon-carbide (SiC) powder to determine bond-strength with bitumen. However, increase or decrease in polishing-level can alter aggregate-roughness and may affect bond-strength. Further, there can be numerous roughness-scale for aggregates such as, arithmetic (Ra), root-mean-square (Rq) and box-roughness (Sa), which needs detailed study. Therefore, one of the strong motivations of this study was to evaluate effects of aggregate-roughness on bond-strength using ABS approach. Similarly, aggregate SFE may change with change in its roughness, thereby affecting aggregate-bitumen bonding. The present study evaluates effects of aggregate-roughness on aggregate-bitumen bond-strength using ABS and SFE approaches. Basaltic substrates and viscosity-grade binder (VG30) were selected for this study. To generate different roughness-levels, aggregate substrates were polished with 220SiC and 1000SiC powders. At each polishing-level, Raand Saparameters were evaluated using zeta-profilometer. The ABS and SFE measurements were conducted on combination of aggregate and bitumen. The results showed that bond-strength increased with increase in aggregate-roughness, indicating better bonding for rough aggregates. Further, Saparameter which remained unaddressed in earlier research studies was recommended to quantify aggregate roughness rather than Raparameters, because it measures roughness over area, which is one of the major contributions of present study.
Dynamic Viscosity Standard of High Viscosity Modified Asphalt Considering Temperature and Load Coupling Effect
Authors: Li Jun , Li Yingtao , Li Mingliang , Lu Haizhu , Cao Dongwei
Published: March 2021

The anti-ravelling and anti-rutting performances of porous asphalt pavement are significantly affected by dynamic viscosity of high viscosity modified asphalt. Climatic and traffic conditions vary greatly due to the vast territory of China, and dynamic viscosity standard has not been recommended up to now aiming at different temperature and load conditions. The influence of high viscosity additive dosage on key property indexes was firstly analysed for asphalt and asphalt mixture, and appropriate dosage was recommended. The dynamic stability changing law of porous asphalt mixture was revealed under different temperature, load and their coupling conditions. Multiple regression relation of them was established. Finally dynamic viscosity standard was proposed considering temperature/load coupling effect. The research results show that when high viscosity additive dosage exceeds 10% for 70# base asphalt, the increasing trend of dynamic viscosity becomes slowing down. Semi-logarithmic relations of dynamic stability with ravelling loss, Marshall stability were respectively found, and double-logarithmic relation of that with dynamic viscosity was found. The appropriate dosage of high viscosity additive is recommended as 12%. Based on multiple regression formula of dynamic stability with dynamic viscosity, temperature and load, the lower limit of 60°C dynamic viscosity is recommended as 50000Pa•s for normal region, 100000Pa•s for heavy-load region, 200000Pa•s for high-temperature region, and 400000Pa•s for heavy-load & high-temperature region.
Application of asphalt rubber cape seal as asphalt pavement surface course for rehabilitated trunk highway in east Gansu
Authors: Han L , Han H , Guo H , Zhu J
Published: March 2021

Although been frequently used as a preventative maintenance measure for asphalt pavements, the Cape seal process has not been widely adopted as a possible alternative for rehabilitated pavement. This research evaluated the feasibility of applying asphalt rubber Cape seal structure into the surface course of reconstructed highway in west China. The Cape seal is composed of 11-16 mm chips spread over asphalt rubber membrane sprayed in advance, by which followed a micro surfacing layer with SBR latex modified asphalt emulsion. Based on a test section in the Banxiao highway project, the construction of asphalt rubber Cape seal and micro-surfacing were investigated experimentally. In addition, to guide the engineers, major issues during construction of the Cape seal were discussed and corresponding countermeasures were suggested.
Feasibility study of low density polyethylene modified bituminous mix in DBM layer of flexible pavement
Authors: Islam SK S , Ghosh A , Ransinchung GDRN , Roy T K
Published: March 2021

An efficient and adequate system of transportation is inevitable for the development of any country. A high traffic intensity in terms of overloaded commercial vehicle, introduction of new axle configuration, significant variations of daily and seasonal temperature of the pavement are significant factors contributing to early development of distress symptoms like ravelling, rutting, cracking, bleeding, shoving and pot holing of bituminous surfacing, which demand a proper strengthening of pavements. The early development of distress in the pavement with the conventional mixes revealed the need of design specification based on performance tests. To overcome such kind of distress, properties of bitumen and bituminous mixes can be improved to meet the requirement of pavement with the incorporation of certain modifiers. The present study evaluates the Low-Density polyethylene (waste milk pouches) modified bituminous mix properties corresponding to the optimum binder content by conducting different performance test. Experimental studies demonstrated that waste milk pouches (6% by weight of the binder) modified bituminous mix gives the best result in terms of stability and durability. Experimental results indicated that using the waste milk pouches in bitumen is not only a cost-effective mix but also a very good solution in terms of improving bitumen pavement mix properties. The present paper aims to highlight the change in properties by addition of modifiers in bitumen and develop a procedure to estimate the reliability of a particular mix design. By considering these aspects, statistically it has been proved that the bituminous mix obtained experimentally, is also reliable to be used in real life scenario.
Prediction of Temperature Cooling Trend of Asphalt Mixtures
Authors: Chu L. , Zhu B. , Fwa T. F.
Published: March 2021

Monitoring of the temperature changes of asphalt mixtures during the mix production and pavement construction phases is important to avoid over-heating, and to ensure that optimum mixing and compaction is achieved. Over-heating or prolonged heating of asphalt mixtures would cause ageing, while inadequate mixing or compaction would result in mixtures with a strength and durability less than design optimal. Careful temperature monitoring would help to avoid such undesirable problems. This study develops a finite-element asphalt mixture cooling temperature prediction software as an asphalt pavement mix design planning tool. For any given asphalt paving design mix, it is able to predict the temperature cooling characteristics of the design mix during the laying and compaction phase. The software can provide the temperature cooling characteristics during a multi-lift paving of asphalt pavement layer. The factors affecting the temperature cooling trend are determined and analysed. They include ambient temperature, laying temperature, solar influx intensity, wind velocity, number of lifts, and lift thickness. A sensitivity analysis is conducted to identify the most influencing factors under different paving conditions.
Effect Dimensions and Shape of Specimens on Some Mechanical Properties of Concrete
Authors: Salman Heba Kadhm , Yaseen Mohammed Hazim , Hamid Rana Mishal , Numan Hesham A. , Noori Abdul_Qader Nihad
Published: March 2021

Due to the effect of the structure element size on concrete’s mechanical properties, larger concrete structures fail under lower stresses than smaller ones. Hence, the laboratory data need to re-evaluate and updated to establish structural design rules and safety regulations. From this standpoint, this research is concerned with studying the effect of dimensions and shapes on the concrete specimen under different amounts of super-plasticizer on the concrete properties. Cubes, prisms, and cylindrical specimens are prepared and subjected to four experimental tests: compressive strength, impact resistance, abrasion resistance, and flexural strength. Besides, four concrete admixtures prepared with different amounts of super-plasticizer, 0.0, 0.50, 1.00, and 1.50 %, as a percentage of cement weight content, respectively. The obtained results from this research proved that both the highest thickness and super-plasticizer dosage resulted in 910% increases in the impact strength and improved in the flexural strength by 56.5%. On the other hand, under all super-plasticizer dosages, an increase in compressive strength, flexural, and impact resistance has resulted. Finally, based on the obtained experimental records, the statistical analysis conducted to present basis formulations illustrated the effect of the dimensions and sizes of concrete specimens with super-plasticizer content on some concrete properties.
A Proposed Approach of Improving Soil Around a Single Lateral Loaded Pile Model by using Nano-Silica Sandy Soil Mixture Material
Authors: Muhammad Ali Rafea Muha , Aziz Laith Jawad
Published: March 2021

This research presented a new method to improve the individual pile’s lateral behavior embedded into sandy soil using silica oxide nanoparticles material. A small-scale model test with many percent of nano-silica material (0, 0.3, and 0.6%) is used at different locations around the pile, such as an adjacent or at a distance of 10 mm away pile face and along pile front or pile behind in additional to untreated soil condition. The nano-silica material is placed into a steel box model as a plane-strain form. The obtained results are presented as relationships among applied lateral load with horizontal, vertical displacement, and rotation. The experimental work results have been validated by comparing with some of the present results (ultimate lateral pile of untreated soil) published by other workers. It clear that the obtained result is in good agreement with Hansen (1961). It is concluded that the perfect percentage of improving the soil by silica oxide nanoparticles was in the (0.6)% because this percentage gave the highest lateral load than that of other percentages at the same lateral and vertical displacement. This is because nanoparticles found in the soil improve the soil’s strength by improving the interaction between soil particles by nanoparticles and filling the voids between soil particles with nanoparticles. All the tests that were obtained for the nanomaterial were mixed and let for three days, and one test was mixed and let for 30 days. This process was for the percentage 0.6 %, so from the results, the perfect period was for three days from the beginning of the mixture of the nanomaterial; this may occur due to the evaporation of the water from the mixture and that lead to a decrease in the interaction between the mixture and the sand in the container when adding the mixture to the physical model.
Assessment of Solar Power Tower System for Closed Space Ventilation: Numerical Investigation
Authors: Wahhab Hasanain A Abdul
Published: March 2021

The small closed space demand increase as a secondary station for commercial production. It leads to the need to improve these stations by enhancing proper self-ventilation and daylighting. The natural air ventilation system significantly works in small closed stations; this system can be improved using different thermal storage materials in the solar collector and integrated approaches in closed space for heating, ventilation, and space conditioning. Three models were simulated; the first model is the normal model (single-pass roof solar collector). The second and third models are solar tower systems; chimney height is 6 m, with external collectors using water and wax containers. Results demonstrated that increasing thermal absorbance (wax container) of the thermal storage unit in the solar collector system enhances system performance. The mean percentage of increasing air velocity between the numerical results of Model-A and Model-B from the standard model is 18.9 % and 11.4%, respectively. Also, the mean percentage of increasing the collector’s efficiency between Model-A and Model-B’s numerical results from the normal model is 8.4 % and 5.3%, respectively.
Optimization of Automotive Bosch-140 Alternator to use as a Generator for Small Wind Turbine
Authors: Abdullah Rawaa J , Mustafa F F , Kadhim H T
Published: March 2021

The generator is one of the costly elements of a small wind turbine. This paper developed a suitable low-cost small wind turbine generator, which can be modified to be easily manufactured. The experiment was conducted in two parts, the first part involves monitoring the current, voltage, power, and temperature for the Bosch 140 alternator before re-winding (initial case), and the second part includes monitoring of parameters (current, voltage, power) with modifying the alternator (Bosch 140) by re-winding depending on the results of the JAMG program simulation (last case). The Bosch 140 alternator was modified consistently by reducing the wire diameter to half to double the windings to evaluate the maximum torque. A genetic algorithm was used to optimize the stator’s design optimization to achieve a maximum torque of the magnet. The final result shows a good indication of the modified alternator’s efficiency, where it is increased by about 30% from the initial case, and the generation of voltage started at a low rotation speed. It was observed that the new optimization of claw-pole alternator provides fairly the double torque with at least 16% reduction in rotation speed.
The Application of Supra_Malleolar Orthosis (SMO) in Iraq: Design and Fabrication Approach
Authors: D Al-Bayati  , Kadhim Ahmed M
Published: March 2021

Due to the importance of the Supra-Malleolar Orthosis in providing treatment for the Iraqi patients, the design and fabrication of Supra-Malleolar Orthosis is presented. This includes studying the material properties and behaviour, and gait cycle for the patient. The experimental part incudes, ratification, molding with inner layer (soft). The material used is called (P-lite or EVA), molding with hard layer. It is polypropylene, reaching the final shape of SMO. Gait cycle for the patient was examined using force plate. Thus, it is found that the orthosis can be manufactured; and tests proved its successful application to satisfy the patient in a sense of comfort. SMOs improve the gait cycles. SMO manufacturing is successful and give good treatment results with low cost.
Investigating the Effects of Climate Change and Sustainable Development of Iraqi Engineers Ethics
Authors: Abbas Yousif H , Hasson Ahmed
Published: March 2021

The impact of heat island is urban in Baghdad, which is a major city colder than the surrounding areas. This study is intended to explain what sectors of the Iraqi society are seen as a concrete challenge to their urban and lifestyle features. Issues about the impacts that climate change and UHI have had on staff were addressed including students and architects, and graduates. The study found that the acceptances of complex issues such as urban heat island as part of climate change and much less recognition of it as the product of human action is moderated in the segments of population of academics, scientists and low among urban residents of Iraqi society. However, low acceptance reflected rather than universal open cynicism a significant degree of confusion among urban citizens. Uncertainty amongst local citizens may be due to theoretical disputes on the causes and potential effects of Urban Heat Island. The findings suggest that scientists are manipulating climate change to follow their own agendas, weakening their faith in research and evidence. This is because of these differences. With just 52 percent of respondents who thought it was easy to comprehend the knowledge presented by climate change and Urban Heat Island, there was a strong need to amend marketing policies in universities and institutes. Results suggest that the Iraqi population’s limited responses to local climate change, current and past extremes of weather warming, water insufficient, and storm seasons support results suggest that Urban Heat Island was not an immediate problem for society. The short to medium term vulnerability Urban Heat Island, defined by their urban climate or lifestyles, was typically not understood or overlooked by a well-educated population.
Experimental Investigation of Sub-Cooled Flow Boiling Heat Transfer in Single Rectangular Metallic Micro-Channel
Authors: Al-Nakeeb Qahtan A , Fayyadh Ekhlas M , Hasan Moayed R
Published: March 2021

In this study, an experimental investigation on the flow boiling heat transfer in single rectangular micro-channel was carried out. The micro-channel was formed by machining 300 μm wide x 700 μm deep groove (i.e. a hydraulic diameter 420 μm) into the surface of brass block having length of 60 mm. The working fluid was deionized water. The experiments were carried out with the mass flux range (300-600 kg/m2.sec), and flux of heat (based on wall) 5.4 to 376.5 kW/m2, inlet sub-cooling of 20 K and 1 atm. working pressure. The results of this study have shown that at heat fluxes with lower range, the local coefficient of heat transfer increased with increasing the flux of heat. This trend is reversed when heat fluxes exceed 64.2, 77.9, 93.8 and 116.7 kW/m2 for mass fluxes 300, 400, 500 and 600 kg/m2.s respectively, where the heat transfer coefficient decreases as the heat flux increases and reach a constant value at the highest heat flux. The experimental results are compared to heat transfer correlations of minichannel and microscale, these correlations gave the results reasonably well.
A Review of Multi-Axial Fatigue Tests
Authors: Almamoori M K , Alizadeh Y , Abolghasemzadeh M
Published: March 2021

Nowadays, estimating the fatigue life of almost any industrial component under multi-axial loads is still a very complicated issue. In this paper, models of multi-axial fatigue for various loading conditions depend on damage parameters conditions shown with a comprehensive review of the multi-axial fatigue machines designed to provide proportional and non-proportional combined loading conditions in the laboratory and corresponding models developed to predict specimens fatigue life. A brief of experimental multi-axial fatigue results reported by previous studies is also presented. Especially, the focus here is on combined bending-torsion and axial-torsion conditions. Such a study allows for a better understanding of the effect of the loading path on material fatigue behaviour during their real operations. Also, predicting fatigue life accurately under non-proportional complex loads will give clear data about when this component is a failure during a real process.
A wavelet-NARX Model for SDINS/GPS Integration System
Authors: Ali Teena Abbas , Hasan Ahmed Mudheher
Published: March 2021

Recently, the Strapdown Inertial Navigation System (SDINS) has been successfully integrated with Global Positioning System (GPS) to obtain reliable navigation solutions. SDINS is based on Micro-Electro Mechanical System (MEMS) sensors such as accelerometer and gyroscope sensors. To improve the overall performance of the integrated navigation system, the Inertial Measurement Unit (IMU) readings is treated through effectively band-limiting the high frequency noise using the Discrete Wavelet Multi-resolution Algorithm (DWMRA) as a first step, while the second step is to enhance the navigation position and velocity through utilizing the Nonlinear Autoregressive model with eXogenous inputs (NARX) to fuse GPS and INS systems. The performance of the proposed integrated navigation system is validated through comparison with other systems. Finally, the obtained results suggest a promising and superior prospect for NARX in the field of navigation for low-cost IMU’s during GPS denied signals, since it outperforms the Conventional Neural Network (CNN) and Extended Kalman Filter (EKF) by 84% and 92%, respectively.
Solution of Inverse and Forward Kinematics Problems for Mobile Robot with Six Mecanum Wheels
Authors: Alwan Hassan M , Volkov A N , Shbani A
Published: March 2021

The wheeled mobile robot has been considered a planner mechanism with linear and angular movement over a horizontal plane. In particular, the wheeled mobile robot’s movement is assumed to result from pure rolling of wheels without slipping. The kinematics model is one of the most fundamental steps in studying any mobile robot. This research presents the kinematic equations of movement of a mobile robot with mecanum wheels. The resulting mathematical model of a wheeled mobile robot was produced using the MATLAB R2014a program. The kinematic modeling technique was investigated by simulating a robot’s walk on a square path.
Numerical Investigation of the Effect of Changing the Thickness of Airfoils used in Wind Turbines on the Lift to Drag Ratio
Authors: Abdulkareem Omar A , Khudheyer Ahmed F , Abbas Ali S
Published: March 2021

In this paper, the effect of changing the thickness of the airfoils on the lift and drag coefficients and lift to drag ratio for three types of airfoils is presented. The study was done by making a 2D simulation by using the commercial software ANSYS FLUENT 2019R1. The airfoils that were selected for the simulation were the NREL S830, SG6043, and SD7062. In order to study the effect of changing the thickness of airfoils on the aerodynamic characteristics, the thickness of NREL S830, SG6043, and SD7062 airfoils was increased and decreased by 20%. The method used to increase and decrease the thickness was done by modifying the coordinates of the upper and lower curves of the baseline airfoils in the y-direction. The simulation was done using the Spalart Allmaras turbulence model for low wind speed (5m/s) and a wide range of attack angles (from 0 to 15 degrees). The aerodynamic characteristics, which are the lift and drag coefficients, lift to drag ratio, and the optimum angle of attack, are presented in this study. It was concluded that reducing the thickness to 20% leads to a remarkable increase in the lift to drag ratio while increasing the thickness leads to a decrease in the lift to drag ratio. It was also concluded that reducing thickness will not always lead to maximizing the lift coefficient but will always reduce the drag coefficient. It was also found that for wind turbines operating in low wind speed regions, the SG6043 airfoil profile is the most suitable as it showed a good aerodynamic performance at low wind speed.
Enhancing Tilt-Integral-Derivative Controller to Motion Control of Holonomic Wheeled Mobile Robot by Using New Hybrid Approach
Authors: Hasan Sameh Fareed , Alwan Hassan Mohammed
Published: March 2021

Trajectory tracking of wheeled mobile robot is the most interesting and important subject in robotic systems field. In this paper, a four mecanum wheeled mobile robot (FMWMR) has been considered. This type was considered because it is the most famous holonomic type of wheeled mobile robot (WMR). The main purpose of this work is to design a new hybrid controller for the trajectory tracking of FMWMR based on the kinematic model. The proposed controller consists of Tilt-Integral-Derivative (TID) controller tuned parameters with neural network as well as social spider optimization i.e., (TID-NN-SSO) which is applied on the kinematic model of the FMWMR. The forward and inverse kinematic equations were derived. The TID controller was used for computing the controlled signals which are the angular velocities of each wheel while the neural network (NN) and social spider optimization (SSO) were to compute the parameters of TID controller. MATLAB/Simulink programing was implemented to simulate the results. A comparative study between TID-NN-SSO and TID controller tuned parameters by using particles swarm optimization (TID-PSO) was conducted. The results of the mean square errors (MSE) in (x and y) coordinates as well as the orientation error obtained from TID–NN-SSO are (2.105*10−4 m, 1.025*10−4 m, 0.0815 rad) and they are less than the MSE that was obtained from TID-PSO which are (0.00567 m, 0.0356 m, 1.22 rad/s). This indicates that TID–NN-SSO is more efficient than TID-PSO.
A Data-Driven Approach Based Bearing Faults Detection and Diagnosis: A Review
Authors: Jawad Saja Mohammed , Jaber Alaa Abdulhady
Published: March 2021

Monitoring the condition of rotating machines is essential for system safety, reducing costs, and increasing reliability. This paper tries to present a comprehensive review of the previously conducted research concerning bearing faults detection and diagnosis based on what is known as model-free or data-driven approaches. Mainly, two data-driven approaches are discussed, which are statistical-based approaches and artificial intelligence-based approaches. The employed condition monitoring techniques in diagnosing faults in different machinery are also deliberated. These include vibration, motor current signature, and acoustic emission signals analysis as they are widely utilized in condition monitoring based data-driven approaches. The advantages, limitations, and practical implications of each approach and technique are presented. However, it has been concluded that very few studies have adopted the statistical-based approach for bearings health monitoring. Thus, it is advised that more investigations have to be conducted in this regard, and hence it will be our next aim.