bluuebunny/crossref_metadata_2025 huggingface dataset:
Steady-state analysis of hybrid solar-wind power integration in 20kV distribution system
Authors: Syafii  , Laksono H D , Alfac A
Published: March 2021

This paper reports the steady-state performance of a grid-connected photovoltaic-wind power system in a 20 kV active distribution system. The system was initially designed to meet a typical of State Electricity Company (Perusahaan Listrik Negara, PLN) primary feeder in Indonesia. In this study, 200 kWp solar power capacity and 200 kW wind power capacity were selected in the simulation of power flow analysis to evaluate the better system states. The results of the study using four cases show that the better voltage profile is obtained in conditions where the hybrid system is placed on the bus, which has the lowest voltage and on the load bus, which farthest from the source. The presence of power injection from solar and wind power plants on low voltage (LV) buses has reduced the active power flow from the grid utility. All load bus voltages have above 0.95 p.u in these cases, already within PLN standard. The lowest level of losses of 11 kW and 50 kVAr are obtained in the case where hybrid Photovoltaic (PV) and Wind Turbine (WT) with capacitor integration in the distribution network. Power losses are secured far below 10% as the losses permitted according to the PLN standard. Therefore, the integration of PV and wind turbine into a 20 kV distribution network can improve the voltage profile and reduce total system losses.
Performance Analysis of Diversity Selection Combining Technique in Rayleigh Fading Channel
Authors: Baharuddin  , Luthfi A , Andre H , Angraini R
Published: March 2021

This paper discussed a performance analysis of diversity selection combining technique in Rayleigh fading channel, in wavelet domain. It proposed diversity selection combining (DSC) method to combat errors during image transmission on wireless channels. The aim of using DSC in the system is to improve the performance of the system. The testing of the system was done by conducting experiment. The experiment was done by testing BER and PSNR. The result showed that BER was decrease to 13.4% in average compared to the system without DSC. PSNR was increased to 2.2 dB in average. The result of this simulation showed that the system with DSC in the image transmission system improvedthe system performance significantly when comparing to the system without DSC.
Design of Polarimetric-Based Optical Current Sensor for Electric Power System Application
Authors: Nasir M , Adrianti
Published: March 2021

Many problems arise in the electric power protection system due to applying a ferrous core current transformer (CT). One of the most crucial problems is a magnetic saturation issue, which tends to cause a measurement error on the secondary side of the CT and could reduce the performance of the protection system. An alternative solution to this issue is the needs to develop an electric current sensor utilizing optical materials. A polarimetric-based optical current sensor (OCS) is a technique considered to be compatible with the future smart grid environment. The OCS principles are based on the magneto-optic Faraday effect that could produce optical rotation in the optical media when a polarized light propagates in those materials. Due to the linear and circular birefringences effect in optical fiber medium are exist, therefore, in this paper the OCS and its associated elements are modelled by considering the birefringence effect in the optical sensor system including optical fiber links. Then, the OCS model is translated to a computer simulation program using a computer application software. Orientation of the second polarizer (analyzer) to the first polarizer in the simulation were conducted using two different angles which are angle α of 45° and 90°. Performance assessment of the OCS model is presented using two various electric current of the power system test to investigate the presence or absence of the saturation effect that may arise in the polarimetric-based optical current sensor model. The simulation results have provided that the saturation effect disappear in the simulation and the analyzer orientation angle α of 45° gives better performances of optical power modulation than the other angle.
Food Waste Composting with The Addition Of Cow Rumen Using The Takakura Method and Identification of Bacteria that Role in Composting
Authors: Dewilda Y , Silvia S , Riantika M , Zulkarnaini
Published: March 2021

The purpose of research to measure and analyse the quality and quantity of food waste composting by adding cow rumen activator and efective microorganisme (EM4). This research do to identify the dominant bacteria that play a role in composting. The composting method applied in this research is Takakura composting. The method for bacterial identification was referred to as the Bergey’s manual which consisted of a gram stain test and a biochemical test. Three types of composter variation are being use in this composting, variation 1 consist of (food waste and maturecompost), variation 2 consist (food waste, mature compost and EM4 activator) and variation 3 consist (food waste, mature compost and cow rumen activator). The parameter which include maturity, quality (moisture content, temperature, pH, texture, color, C/N ratio, P and K), and the quantity of compost. The results showed that not all variations met the compost maturity and compost qualitybased on the SNI 19-7030-2004 standart such as organic carbon in variation 1B and C/N ratio in variations 1A and 1B. The affects of addition activators to composter give short time and good quality of compost. Composting with the addition of cow rumen activator is the fastest composting for 7 days with C/N ratiois 19.22%, P is 0.34%, Kis 2.08%. Composting with EM 4 activator occurred for 8 days with C/N ratio is 20.53%, P is 0.30%, K is 1.82%. Composting without the addition of activator is the longest composting which is 11 days with C/N ratio is 23.74%, P is 0.21%, Kis 1.76%. The results show variation 3 with the addition of cow’s rumen is the best composting with a score of 15. The results of the identification of dominant bacteria that a role play in composting are some Bacillus sp bacteria which are bacteria that degrade organic matter.
Performance of anammox biofilm reactor under tropical temperature
Authors: Zulkarnaini Z , Primasari B , Saputra D J
Published: March 2021

Application of anaerobic ammonium oxidation (anammox) process for mainstream wastewater in the lower temperature is a current challenge where most of the anammox reactors planted in the sub-tropical country. The purpose of this study was to analyze the performance of nitrogen removal using anammox process at room temperature in a tropical country. The experiment was carried out using 300 mL an up-flow anaerobic sludge blanket (UASB) reactor in treating low ammonia concentration artificial wastewater at tropical temperature without any adjustment. The reactor filled with 50% in volume spiral-sheet plastic (polyethylene terephthalate) as the carrier. Anammox bacteria Candidatus Brocadia sinica as seeding acclimatized in room temperature for three months before the experiment. The reactor fed with 70 mg-N/L for both ammonium and nitrite with variations in hydraulic retention time (HRT) 24 hours and 12 hours. The maximum nitrogen removal rate (NRR) achieved 0.12 kg-N/(m3·d) at nitrogen loading rate (NLR) 0.14 kg-N/(m3·d) and NRR 0.25 kg-N/(m3·d) at NLR 0.28 kg-N/(m3·d). The anammox process was stable at room temperatures (15-28°C) in a tropical country for nitrogen removal and anammox bacteria grown on plastic media.
Effect of Occupational Noise Exposure to Work-Fatigue of Indonesian Crumb Rubber Plants
Authors: Ihsan T , Afriani N , Edwin T , Derosya V , Sari P N
Published: March 2021

The purpose of this research was to analyze the effect of noise on the level of work-fatigue in the production area of three crumb rubber plants at Padang City, Indonesia. It also examines the impact of age, period work, marital status, and education level on work-fatigue. Occupational noise in the working area was measured using a Sound Level Meter, while work-fatigue was measured using the Indonesian fatigue measurement questionnaire (KAPUK2). The respondents of this study were workers in these plants, 213 people in the wet-area, and 135 people in the dry-area. Results showed that the average noise of the production area had exceeded the threshold value, which was 90.98 dB. There were 26.19% experienced mild-fatigue, 71.43% moderate-fatigue, and 2.38% heavy-fatigue. Noise, age, and working experience were a related and significant influence on work-fatigue, where the probability value was respectively 0.046, 0.001, and 0.000 (p≤ 0.05). The results of multiple regressions showed that occupational noise was the most influential factor in the occurrence of work-fatigue with an odds ratio of 3.92.
Designing carbon dioxide absorbent and detector products using the Quality Function Deployment (QFD) method
Authors: Ginting R , Ramadhan M
Published: March 2021

Global warming is defined as an increase in the average temperature of the earth’s surface caused by an increase in the amount of greenhouse gases in the earth’s atmosphere. The largest contributor to greenhouse gases on earth is carbon dioxide (CO2). It is hoped that this CO2 detector and absorber tool can solve the problem of harmful gases generated from existing industries. This tool is silver with a size of 30 × 30 cm, and the material used is aluminum and has an additional function in the form of a coil cable. The design of this tool uses the method of brainstorming techniques and sampling techniques by means of open and closed questionnaires to determine the type of product. After that, a market survey is conducted using sampling techniques and determining the validity and reliability of the product with competitor I, competitor II and competitor III. The stages from problem to sub problem are determined to classify the goals that will be made in designing the product. Sub-problem to sub-solution steps are carried out to determine the Quality Function Deployment (QFD) of the product.
Evaluation of e-commerce services quality using Fuzzy AHP and TOPSIS
Authors: Ishak A , Ginting R , Wanli W
Published: March 2021

Rapid technological developments require people to use information and communication technology to transact goods/services. Based on a survey by the Central Statistics Agency (BPS), of all data collection efforts, only 15.08% are e-commerce entrepreneurs. This shows that business conducted via the internet in Indonesia is still low. The low utilization of e-commerce can be caused by several obstacles, one of which is the customer trust that is built when customer satisfaction is met. This research was conducted to evaluate the quality of e-commerce services using Fuzzy AHP and TOPSIS. The determination of sub-criteria is done using the Delphi method. After that, the calculation of consistency is carried out using the AHP method. The results of calculations using Fuzzy AHP-TOPSIS show that the best e-commerce orders are Tokopedia (0.6206), Bukalapak (0.5208), Elevenia (0.2094) and Shopee (0.1910). Based on the research results, the recommendation for e-commerce with the best service quality is Tokopedia, this is because Tokopedia has the highest weight on the sub-criteria for product return services compared to other e-commerce. The results of this study can be used by other e-commerce companies to improve service quality based on criteria and sub-criteria that are considered important according to expert opinion.
Structure modeling and analysis for improving the strength of horizontal pump system
Authors: Haryanto I , Yohana E , Mahdi I , Sihotang I H , Choi K-H
Published: March 2021

Generally, pumps are used as equipment to move liquids from one place to another, such as in power plants, petroleum companies, etc. One of the kinds of the pump is the Horizontal Pumping System which consists of a motor, trust room, cradle, pump, and base. This study is motivated by the problem appearing of load increase at the suction and discharge nozzle so that it exceeds the allowable load. That load surges cause the pump structure to receive large vibrations, which results in damage to some Horizontal Pump System structures. Therefore, structural analysis on the Horizontal Pumping System to determine the displacement and durability of each cradle are necessary. The purpose of this study is to determine the strength of the pump structure and design additional tools to strengthen the pump structure. In this study, SOLIDWORKS is used for 3D modeling of the Horizontal Pump System structure. Meanwhile, the strength analysis of the structure is conducted using ANSYS Static Structural. Based on the analysis results, there is a quite large displacement in the pump section associated with the suction nozzle. On the other hand, the cradle resistance is still in the elastic deformation area with a maximum value of 24881.97 psi (σy = 3.01x104 psi). Therefore, development is needed by adding a cradle in the pump section associated with a suction nozzle. By adding this cradle there is a reduction in displacement experienced by the pump. Pump displacement changes to 0.036 - 0.097 inches in x-axis, 0.009 - 0.021 inches in y-axis, and 0.001 - 0.005 inches in z-axis.
Preparation Smallest PVA/Binahong Leaf Nanofiber for Wound Dressing Applications by Varying Electrospinning Variable using Taguchi Method
Authors: Ridwan F , Ananta A A
Published: March 2021

Binahong leaf is one of the herbal plants known to have interesting properties such as accelerating wound healing, anti-bacterial, etc. Converting Binahong leaves into fiber will increase their effectiveness because they are easier to absorb. The electrospinning method is used to convert Binahong polymers into Binahong fibers. The Taguchi method is used for experimental design with three factors and three levels. The resulting fiber properties vary with each variation factor. The smallest fiber obtained was 459,993 nm with tip and collector distance, voltage, and weight% PVA, respectively, 8 cm, 20 kV, and 8% (98.6922 P). Wound dressing by using Binahong nanofiber is possible.
Construction technology and treatment effect of RoadMesh reinforcement in joint section between new and existing asphalt pavement
Authors: Xiao Q M , Zha X D , Hu H W , Chen H P , Wang Z W , Wu H
Published: March 2021

In order to verify the application effects of pavement reinforcement technology with RoadMesh steel wire mesh, and relied on the S415 Reconstruction and Extension Project from Xiapuzhen to Jietoutang in Tongshan County, Xianning City, Hubei Province, the application researches on construction technology and treatment effect of RoadMesh reinforcement were carried out for the joint section between new and existing asphalt pavement through scheme design, field construction, tests and analysis and economic comparison. The results show that the tensioning and fixing of RoadMesh are the key construction processes, and the arching and rolling of RoadMesh should be strictly prohibited during its construction. The asphalt pavement performances of RoadMesh reinforcement is better than that of unreinforcement, and the reinforcement effect between lower surface layer and base layer is better than that between base layer and subbase layer. The RoadMesh can effectively improve the integral bearing capacity of asphalt pavement structure and the resistances of reflection cracking and differential settlement in the joint section between new and existing pavement. Compared with the traditional reinforcement of geotechnical synthetic materials, the RoadMesh has higher performance price ratio and better long-term pavement performances. Therefore, the pavement reinforcement technology of RoadMesh can be widely popularized and applied.
A review on the application of natural rubber as asphalt modifier
Authors: Ansari A H , Jakarni F M , Muniandy R , Hassim S
Published: March 2021

Natural rubber as bio-modifier of bitumen and asphalt mixtures has shown to have some beneficial effects. As initially produced, natural rubber consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds, plus water. Natural rubber can consist of various forms including as latex, which is a sticky, milky colloid; cup lump which is a coagulated latex and ribbed smoke sheet. Natural rubber is used extensively in many products and applications, either alone or in combination with other materials as it has a large stretch ratio and high resilience, and extremely waterproof. Due to these properties together with a chemical composition which can be classified as elastomers, natural rubber modification can improve the performance of conventional asphalt mixtures that are currently faced limitation against increased traffic loading and higher axle loads together with the effect of ageing, moisture, and temperature. Also, the application of natural rubber as part of the construction of asphalt mixture pavement might support the national agenda to boost rubber industry. This paper will review the application of various forms of natural rubber as modifier either in bitumen or asphalt mixtures based on previous studies done by other researchers. Numerous studies have been conducted based on different types and composition of natural rubber to determine the performance especially in terms of rutting and fatigue cracking properties.
The effect of using asbuton with used waste diesel oil on the stability of the porus asphalt mix with hot mix cold laid method
Authors: Gusty Sri , Erniati  , Yosis
Published: March 2021

The abundant availability of Asbuton in Indonesia should be proportional to the percentage of its use, however, in the implementation of pavement works, it is still dominated by petroleum asphalt, the price of which tends to be higher than the Asbuton. If you look at the elements in Asbuton, namely minerals and bitumen, it should be superior to petroleum asphalt. One of the factors where the use of Asbuton is not optimal is that the stability value of the mixture using Asbuton is still low compared to the mixture using petroleum asphalt. So this research aims to analyze the stability value of the porous asphalt mixture using Asbuton and waste oil as a rejuvenating agent with hot mix cold laid method. The research method was carried out by carrying out test objects with variations in Asbuton content of 5%, 5.5% and 6% with variations in fuel wastage rate of 0%, 2%, 3% and 4%. The total number of test objects is 36 samples. Then the Marshall test was tested to determine its stability value. The results obtained based on the test results are the highest average stability value at the variation of the levels of Asbuton 6%, 5.5% and 5% respectively 1295.3 Kg with 4% waste oil content; 1238 Kg with 3% used oil; and 773 kg with a waste oil content of 2%. Adding the Asbuton content increases the stability value; however, the level of used oil in the best results still varies. It can therefore be concluded that the highest stability value of a hollow asphalt mixture using an Asbuton content of 6% and a waste oil content of 4% with a value of 1295.3 Kg, meets the specification of the Road Engineering Association of Malaysia (REAM).
Study the Possibility of using Fiber and Polymer Composite Materials in Helical Spring Manufacturing
Authors: Rasol H A , Ismail M R , Najam A A
Published: March 2021

This work deals with studying the possibility of introducing new material into the spring manufacturing and study the properties of this spring and the load-carrying capacity when it is facing compression load. Then, specifying the application that this new composite spring could be used for. One of the applications of springs are in the suspension system, and the primary demand that the designers of automobiles are looking for is improving fuel efficiency, which may be related to the weight of the vehicle. In this research, the steel spring has been replaced by glass and carbon fibers composite with polyester resin as a matrix material. Theoretical analysis has been conducted, and numerical analysis of spring was performed using ANSYS WORKBENCH to simulate the spring under axial compression load. A comparison between the the theoretical and numerical deflection results has been made to predict the best material that can be used for replacement the steel spring. The second part of the research is the selection of materials and the utilized mold in the manufacturing process of the composite helical compression spring by using fibers, it was found that carbon fiber spring has results near to steel spring with stiffness 5.66 and steel 5.49 and glass composite spring 5.018 and carbon composite deflection was less than the glass composite deflection.
Artificial Neural Network Control of a Multiple Effect Evaporators via Simulation
Authors: Ahmed Duraid F , Khalaf Zainab A
Published: March 2021

This research studies the dynamic model and control of multiple effect evaporators of tomato solutions by implementing three control strategies: PID, neural model reference, and neural model predictive controllers. The evaporator’s control is crucial to maintain the product specifications at different operation conditions at minimum operating cost. The model reference control and model predictive control has been designed and evaluated. The simulation results showed that the neural predictive controller is more suitable, has lower overshoot, less offset value, and less integral absolute error.
Study the Effect of Phase Change Material on the Performance of Evacuated Tube Heat Pipe Solar Collector under Iraqi Climatic Conditions
Authors: Ali Sarah H , Eidan Adel A , Sahlani Assaad Al
Published: March 2021

This work presents an experimental study to investigate the effect of integration phase change material (PCM) on thermal performance and efficiency of heat pipe-evacuated tube solar collector (HP-ETSC). The experiments were conducted under the Iraqi weather condition during the winter season (January, February, and March). To thoroughly investigate the thermal performance of HP-ETSC, a new experimental test rig was designed and manufactured based on standard criteria. The results showed that when integrating PCM with the system, it can significantly enhance the thermal capacity of the HP-ETSC system. The efficiency is increased by 3-5% and maintains the high temperature of water for a longer time at night. Moreover, the coefficients of evaporator heat transfer (EHTC) and condenser heat transfer (CHTC) of the heat pipe are also increased. The results from the developed HP-ETEC system are promising, and this experimental model can be applied using different types of phase change materials that are suitable to be used in Iraq.
Improving the Value of the Power Coefficient for Three Straight-Blades Darrieus Wind Turbine
Authors: Khammas Farhan A
Published: March 2021

In this study, an experimental test was carried out using a subsonic wind tunnel to study the improvement of the power coefficient of the three straight-blade Darrieus vertical axis wind turbine. A three-blade vane type vertical axis wind turbine with three movable vanes in each of the blades was fitted in the middle of the three straight-blade Darrieus (0012 Airfoil) vertical axis wind turbine, and they are installed on the same rotor shaft. For this purpose, two vertical axis wind turbine, the first one has three straight-blades Darrieus of type 0012 Airfoil and the second also has three straight-blade Darrieus but of type 0012 Airfoil with a three-blade vane type vertical axis wind turbine with three movable vanes were manufactured. Both turbines were tested using a subsonic wind tunnel at different wind speeds ranging from (4-28) m/s. The consequences showed that in the second turbine test, a power coefficient of Cp=0.39 was obtained, which is greater than the power coefficient of the first turbine (Cp=0.184) after the turbines were tested in a wind tunnel under identical conditions at a wind speed of 6 m/s. Therefore, the second wind turbine produces greater electrical power than the first wind turbine.
A Stochastic Approach to Identify POS in Iraqi National Song using N-Iterative HMM using Agile Approach
Authors: Jassim Abbood Kirebut , Al_Bayaty Boshra F Zopon
Published: March 2021

This research article conveys the use of an agile approach for building an N-iterative HMM model for POST (Part of Speech Tagging) analysis. The agile model is a phenomenon or approach which has vast application. The implementation of such an iterative model is discussed in this paper. Most effectively, the information is conveyed with the help of the exact word we use during the communication. The sentence may not be a complete sentence or grammatically correct sentence, but the purpose of communication is served without any hurdle. Ages witnessing the evolution of the language earlier medium was sign language that might not contain any language communication rules that can be completed. Now complete language with so many tools and API is available, but the way preferred for the processing is the same (logically). The designed iterations lead to improved quality validation by using the word by word score calculation. The experiment is conducted to complete Part of Speech Tagging (POST) for Iraqi National Song (data set of translated Iraqi national song), and the stochastic approach used for completing the tagging is Iterative Hidden Markov Model. The results of the experiments convey the positive impact of the iterative approach over accuracy.
Cloud Computing and its Impact on Online Education
Authors: Al-Malah Duha Khalid Abdul-Rahman , Aljazaery Ibtisam A , Alrikabi Haider Th Salim , Mutar Hussain Ali
Published: March 2021

The cloud computing system has a significant role in the distance education field, because it is an important tributary of virtual education, especially mobile and blended education. Perhaps, the only challenge that must be overawed is the comprehensive coverage of rapid access to the Internet. So, the student can benefit from the applications that we will call from now and onward cloud computing services. There is no need to establish evidence to emphasize the importance of employing technological innovations to develop educational practices for developing educational curricula in Iraqi universities, but it is vital to employ technological innovations in the educational process, and this must be related to overcoming the problems facing the educational process. Therefore, employment should not be for technological dazzling that often accompanies technological innovations, but employment must be a function of urgent needs or demands. In this study, the educational process concept, with its multiple cloud inputs and outputs, was discussed how the education crisis could be overcome in all its institutions by resorting to how to employ the electronic cloud in distance education. This study also examined all the specifications of that environment and the possibility of their application in colleges and educational institutions.
Design of Optimum SIMO-PID Neural Voltage-Tracking Controller for Non-Linear Fuel Cell System Based on a Comparative Study Of Various Intelligent Swarm Optimization Algorithms
Authors: Dhahad Hayder A , Dagher Khulood E , Al-Araj Ahmed S
Published: March 2021

This paper presents the enhancement of the output performance of a non-linear fuel cell (FC) system using a new design that comprises an adaptive SIMO-PID neural controller with different types of online swarm optimization algorithms. The work focuses on improving the use of single-input multi-output (SIMO) PID neural networks to control the non-linear FC system. The goal of the proposed adaptive SIMO-PID neural voltage-tracking controller is to rapidly and precisely identify the optimal hydrogen flow rate and oxygen flow rate control actions that are used to control the (FC) stack terminal output voltage. Three swarm optimization algorithms are used to find and tune the weights of the SIMO-PID neural controller: the Firefly algorithm, chaotic particle swarm optimization algorithm, and proposed hybrid Firefly-chaotic particle swarm optimization (F-CPSO) algorithm. Numerical simulation results show that the proposed controller using the (F-CPSO) algorithm is more accurate than with the FA or CPSO; the proposed SIMO-PID neural controller parameters are obtained more rapidly there is a high reduction in the number of function evolutions. Furthermore, the proposed controller’s ability with the F-CPSO algorithm to generate a smooth flow rate control response for the non-linear (PEMFC) system without voltage oscillation in the output is determined by investigations under load variations.
Cognitive Radio using Spectrum Sensing by Cooperative Two Secondary Users
Authors: Al-Dulaimi Omer Mohammed Khodayer , Vlâdeanu Câlin , Martia Alexandru , Al-DulaimiMohammed Aymen Mohammed Khodayer , Al-Dulaim Mohammed Khodayer Hassan
Published: March 2021

In cognitive radio systems, users that are cognitive (unlicensed) must constantly scan the spectrum for primary (licensed) users to be present. In this article, the researchers display the benefits of cognitive radio collaboration. It is demonstrate that detection times can be reduced by motivating cognitive users to cooperate in the same band, thus increasing overall agility. Next, a cognitive two-user radio network is depicted and a method to exploit the inherent network asymmetry to improve agility. It is shown that our cooperation program improves the efficiency of cognitive users by 35%. The researchers then extend the cooperation scheme to two user-per-carrier multi-corporate networks and calculate the gain in asymptotic agility.
A Review of Collapsible Soils Behavior and Prediction
Authors: Mahmood Mohammed Shakir , Abrahim Mustafa Jamal
Published: March 2021

Collapsible soils are present in arid and semi-arid regions in an unsaturated state and are considered to be one of the problematic soils that face engineering and geotechnical challenges. They are regarded as sensitive soils where their structure and engineering properties change upon wetting (leaching or soaking). The wetting leads to a break in the bonds between the soil particles (salts or clay) and a decrease in the suction power that binds the soil particles together. Large settlement occurs and thus causing problems for the buildings and facilities constructed on them. Recognizing the properties and characteristics of collapsible soils is very important in order to know how to deal with them to avoid unnecessary financial losses and problems. This paper gives an overview of collapsible soils behavior and prediction in many aspects.
Effect of Adding Sawdust to Cement on its Thermal Conductivity and Compressive Strength
Authors: Hafidh Sanaa A , Abdullah Thamer A , Hashim Fanar G , Mohmoud Bashar K
Published: March 2021

In this practical study, the thermal conductivity and compressive strength of a number of cement mortar and sawdust mixtures were measured. This study aims to analyze the possibility of using these mixtures as thermal insulators in the building parts. The materials used in the study were ordinary Portland cement available in the local Iraqi market, sand, and sawdust. Samples were prepared according to American standards. Sawdust in two different sizes (greater than 50 mm and less than 1.4 mm) was added to the cement. The study results showed that adding sawdust caused an apparent decrease in the mixture’s thermal conductivity, which means an improvement in the thermal insulation of the mixtures. The decrease in conductivity also raised with the sawdust mass fraction increase. The thermal conductivity of sawdust and cement mixtures increased when using small sawdust (less than 1.4 mm) compared to the second case (sawdust of large size above 5 mm). The mixture’s thermal conductivity decreased with the increase in the water curing period, and the decrease in conductivity increased with this period. Increasing the sawdust mass fraction resulted in a decrease in the studied mixtures’ compressive strength, and this resistance decreased more when using sawdust of smaller sizes (less than 1.4 mm). The compressibility strength of all the studied products increases with the increase in the treatment time with water due to the cement’s properties.
Water Hammer Mitigation by Air Vessel and Bypass Forward Configuration
Authors: Mery Hadi O , Hassan Jafer M , EKaid Ali L
Published: March 2021

In many industrial applications, liquid is transported by pipelines under high pressure conditions. Thus, any considerable change of fluid velocity will induce destructive pressure waves which may threaten the safety of the hydraulic system. Therefore, finding an effective and appropriate transient control technique is the objective of most related studies. In this paper, the effect of air vessel and HDPE (high density polyethylene) forward configuration techniques on the induced pressure waves were investigated experimentally and numerically. As the transient conditions are triggered owing to the sudden pump trip, each control technique was individually and jointly implemented. Regardless of control devices, the effect of changing the control operational scenario on the generated pressure waves were further investigated. Consequently, the experiments revealed that air vessel and HDPE forward configuration techniques have considerable damping effect to attenuate the water hammer, but the combination of both techniques has higher damping efficiency. Equally important, the changing of the operational scenario affects the severity of the induced surges. As well, the performance of air vessel and the HDPE forward configuration was affected by changing the operational scenario. Finally, the experimental and the numerical results are reasonably converged.
Design and Fabrication of a Nano-Microfluidic Device for Blood and Cancer Cells Separation
Authors: Ali Saad Mahmood , Attallah Saja Basher , Karim Shafaq Hussein
Published: March 2021

In the present work, an attempt has been made to develop, design, and fabricate a low-cost, easily operable micro-fluidic device used for separation, filtration, and purification of the cancer cells from the blood. The fabricated device can also be used for purification and separation of different chemical particles. The response surface methodology (RSM) technique, the full factorial design (FFD), and the expert system 11.0 software program were selected to design, improve, and assess the experimental work. The fabricated device efficiency was tested and evaluated by implementing several experiments. The designed experimental input parameters were the separation method (horizontal, vertical, and the microfluidic method for white blood cell (WBC) separation system; the microfluidic Pore Size 0.43, 3, 8, 12 μm and the air pressure level (0, 50, 100 and 150 mbar). The main experimental results of current research showed that the blood and the rates of cancer cells separating and filtration were increased with increasing the air pressure levels and the microfluidic pores sizes. The best results were obtained for cancer, and tumor-free cell separation rate at an air pressure of 150 mbar with using the horizontal separation system reached 16.91ml, or 3.38 ml/min, which are higher by 2.8 times than the efficiency of the use of the vertical system. The highest quantity of the separated (WBC) was obtained under the same conditions, reached 17.14 ml, or 3.43 ml/min, which is higher than the vertical system’s efficiency by 3.4 times, and higher by 30.08%. Compared with the use of the microfluidic (WBC) separation system. The best-obtained results of red blood cell (RBC) separated quantity reached 5.71 ml or a rate of 1.142 ml/min, which is higher than the efficiency of the vertical system separation by 90.33%. The highest blood cells filtration and purification quantity from the blood-related viruses and bacteria were obtained at 100 mbar air pressure, and the use of the vertical separation system reached 2.50 ml. or at a rate of 0.5 ml/min, which is higher than the productivity of the horizontal system by 8.6 times.
Network Management in Software-Defined Network: A Survey
Authors: Rasool Zaid Ibrahim , Ali Ridhab Sami Abd , Abdulzahra Musaddak Maher
Published: March 2021

SDNs are developed networks that focus on the separation of control aircraft and data. This new model is designed to simplify network management and enable research innovations. It explains the traditional system of SDNs and issues related to the traditional system. This paper explains the background of SDN technology and architecture. At the end of the research, SDN enhances scalability, flexibility, reliability, high availability, security and performance. This paper has tried to simplify and explain every problem with the SDN network and provided an overview of the SDN network general structure, the basics of network management in SDN, and the main challenges in SDN.
Impact of Heavy Hydrocarbon Concentration on Natural Gas Flow through Transportation Pipelines
Authors: Abd A A , Naji S Z , Alwan H H , Othman M R , Tye C T
Published: March 2021

In this work, binary, ternary, quaternion, and quinary natural gas mixtures were evaluated including methane, ethane, propane, butane, and pentane to highlight their impact on pipeline performance and thermophysical properties of natural gas. The results presented that all the heavy hydrocarbons have a negative impact on natural gas phase envelope. For binary mixtures, methane/propane recorded the widest two-phase envelopes while the quinary mixtures generally formed the widest two-phase envelopes over the other mixtures. Besides, the heavy hydrocarbons content of different mixtures increased the critical pressures and critical temperatures in comparison to pure methane. The highest temperature drop of 6.495 °C was recorded by the binary mixture and the lowest temperature drop of 6.341 °C was by quinary mixture. The highest pressure drop of 4.964 bars was caused by the quinary mixture, while the lowest pressure drop of 4.1 bars was by the binary mixture. In addition, the results showed that natural gas density controlled by methane content caused increasing the methane content resulting in reducing the density of natural gas mixture. The viscosity of natural gas is a sensitive parameter to the content of the heavy hydrocarbon concentrations and all heavy hydrocarbons increased the viscosity of natural gas in comparison to pure methane.
Numerical Modelling of Laminar Forced Convection in a Variable Cross-Section Circular Pipe
Authors: Ahmed Sahib Shihab , Almadhhachi Mensour S , Ghyadh Nabeel Abdulhadi
Published: March 2021

A study of three dimensional laminar forced convection with conjugated heat transfer for water flowing inside a circular pipe with variable cross-section area has been numerically conducted. The thermal performance and pressure drop under constant heat flux are also estimated. In this paper, using FLUENT ANSYS, the finite volume method (FVM) is used to evaluate the continuity, momentum, and energy governing equations. For a range of Reynolds numbers less than 2000, heat transfer rates were computed, and Prandtl number equal to 3.7. The effects of Reynolds number and divergent angles (ratio) on the convection coefficient of heat transfer (h) drop in pressure (ΔP), and the thermal-hydraulic performance (η) are analyzed and discussed. The results showed that the use of the divergent ratio increases the thermal-hydraulic performance. Compared to the uniform pipe, it is increased by 23% with a maximum pressure drop decrease by about 240% for ratio=1.8. With the empirical Shah equation, the current model is validated, and the results showed excellent agreement.
Determination and Analysis of Residual Stress for AISI L2 Tool Steel in Electric Discharge Machine (EDM)
Authors: Aghdeab Shukry H , Shwaish Raed R , Salman Tahseen M
Published: March 2021

Electric discharge machine is one of the most important non-traditional cutting processes conducted without contact between the workpiece and tool electrode. Each cutting process was associated with residual stresses, and these stresses are significant in determining life and product performance. This study aimed to determine the residual stress produced in the electric discharge machine (EDM) using the X-ray diffraction method. The used EDM parameters in this study are current Ip (10, 20, 30) A, pulse on-time Ton (50, 100, 150) μs, and pulse off-time Toff (6.5, 12,25) μs these parametric divided into 27 specimens. Full factorial was used to analyze the result using Minilab 17 software. The result showed that approximately between the experimentally and predict result. Also, the result illustrated that the residual stress was increasing with increases in each parametric EDM used. Maximum tensile residual stress is (838.86 Mpa) at a higher value of machine parameters, while the best residual stress achieved is compressive residual stress at low machine parameters, and it reaches 201 Mpa.
The Influence of Nano-Silica on the Properties and Microstructure of Lightweight Concrete: a Review
Authors: Al-Luhybi Ashtar S. , Altalabani Diyar
Published: March 2021

In recent years, the use of nanotechnology materials has increased in strengthening and enhancing the behavior of concrete and its mechanical properties. This is due to the special characteristic of these materials such as its tiny size that considerably improves the microstructure of concrete, which in return gives concrete new properties and dramatically enhances its behavior. The present study seeks to review several previous studies that investigated the effect of adding nano-silica on the mechanical properties, durability, transport properties, and microstructure of lightweight concrete. Based on the results, it has been noted that the addition of nano-silica material has a vital role in improving the properties of lightweight concrete. Moreover, it was observed that there is an increase in the compressive strength, tensile strength, and flexural strength due to the addition of nano-silica material. It has also been concluded that there is an improvement in the durability and transport properties of lightweight concrete.
Using Digital Sustainability in Conserving the Architecture and Urban Heritage
Authors: Al-Mudhaffer Ahmed Faik , Baqer Moha Humam , Saleh Saif Kadhum , Kadhum Ghassan Ibraheem , Mohammed Noor Jasim
Published: March 2021

In recent decade, as the results of frequent wars and internal conflicts, many archaeological and heritage regions of Iraq were subjected to sabotage and looting. Some of these regions were totally destructed. Therefore, searching for mechanisms, means and methods for conserving and reconstructing the heritage is of great importance. This research presents a new proposal that contributes to the conservation of heritage and antiquities virtually through digital sustainability and digitization. This digital conversation in some ways helps in conserving the legacy of the cities that were damaged and destroyed by wars. Additionally, it allows users and those who are interested in heritage in different countries of the world to digitally tour the archaeological city and to see its old features and elements as if they were on the ground of reality. The aim of the research is to “achieve sustainability in preserving heritage and architectural architecture virtually through digital sustainability as it is a reference in the event of the disappearance of heritage buildings in reality”. The research uses auto-cad electronic program, for the purpose of digital documentation of the building. After taking measurements and images using traditional means from measuring tools and the camera, auto-cad used for drawing and then documentation using the calculator. The research has reached a set of conclusions which relate to the interest in heritage and conserving it benefiting from digital sustainability. These cities can be virtual cities with the aim of containing the treatments and heritage elements of the city and buildings.
Aerodynamic Study of Low-Speed Wind Tunnel Contraction Section: Design and Manufacturing
Authors: Kareem Alaa A , Abbas Mohamad K , Khammas Farhan A
Published: March 2021

This work aims to improve the visualization of a subsonic open section type smoke tunnel, which already exists in the AL-Nahrain University/College of Engineering/Mechanical Department Laboratory. This study focuses on modifying the contraction section only to improve the airflow properties in the test section. A numerical study with ANSYS FLUENT R19.0 was carried out to characterize the flow via the contraction section. The parameters that are suggested to be modified are the wall profile and the length of the contraction section. The analysis includes the original contraction section and suggested new profiles to be compared under the same boundary conditions. The new suggested profiles for this work are polynomials of orders (6th, 7th, 8th, 9th, and 10th). A unique analysis is achieved for the 9th order profile, where it is tested with four different inflection points (0.5L, 0.55L,0.6L, and 0.65L). The study focuses on the uniformity, turbulence intensity, boundary layer thickness at the contraction section exit plain, beside the boundary layer separation along with the contraction as comparing parameters. Experimental work was done to validate the numerical results. The experiment work includes building a half-scale of the original smoke tunnel to monitor the new contraction’s direct influence on the test section’s flow. The result showed that the 9th-order wall profile with an inflection point at 0.65L and length of 0.93m is the pest contraction for the aimed smoke tunnel.
The Effect of installation Torque on the Behavior of Helical Piles under Compression Load Tested by Centrifuge Device
Authors: Jabur Jaafer A R , Mahmood Mahmood R , Abbas Saad F
Published: March 2021

In complex geotechnical problems, to perform a realistic study related to the soil-structure interaction and bearing capacity of foundations, a centrifuge modeling must be considered. New centrifuge device for installation and testing screw pile models is designed and manufactured with different velocities depending on the value of N (gravity scaling factor) and applying compression, uplift and inclined loads during rotation and their electronic control. The new installation system for helical piles was used in this device to install each pile with different torque depending on its capacity. Helical piles represent one of the deep innovative foundations as an alternative for increasing the size of the existing foundation solutions. In this study, the helical pile models are tested by centrifuge device with different parameters embedded within sand with relative density (R.D) of 75% and 55% under compression load. These parameters are spacing ratio, diameter and number of helices. The installation torque causes a soil disturbance which increases by increasing the diameter of helix and R.D of soil. The reduction percentages of the bearing capacity of the helical pile models with two helices of diameter (40 mm) embedded in sand with R.D of 75% and 55% are 17% and 9%, respectively, and when R.D of (55%) and helix diameters of 40 mm and 50 mm are 9% and 15%, respectively.