bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of bagasse ash, calcium carbide residue and polyester fiber addition on shear strength of organic clay
Authors: Hatmoko John Tri , Handoko Luky 
Published: March 2021

Abstract
Organic clay has bad engineering properties. It is compressible, sensitive to the changes of water content; and it has poor bearing capacity and shear strength. Therefore, the research regarding improvement of this soil is intensively performed and continually in progress. In this research, bagasse ash (BA), calcium carbide residue (CCR) and polyester fiber were used to improve the shear strength of organic clay. A set of laboratory experiment were performed to study the effects of BA, CCR and polyester fiber inclusions on the shear strength of organic clay. To obtain optimum moisture content (OMC), standard compaction test was worked out for original soil. The oven dried BA (varied as 10 %wt, 20 %wt and 30 %wt) were mixed with the soil, and water was added to its OMC. Then, 1 to 2 %wt freely oriented polyester fiber was mixed with BA-soil samples. The BA-soil specimen and BA-soil specimen containing polyester fiber was investigated through direct shear tests. Finally, 4 %wt CCR was added to both BA-soil mixtures, and BA-soil mixture with fiber inclusion. The direct shear tests were then carried out on those samples with 14, 28 and 36 days curing period. This research shows that calcium carbide residue increases shear strength of BA-soil samples and BA-soil specimens with fiber inclusion. It shows also that fiber inclusion increases ductility of treated soil. However, the use of BA only does not significantly increase the shear strength of stabilized soil.
The formulation of mangosteen peel extract microencapsulation on water content and fungus distribution during storage
Authors: Kusmayadi Andri 
Published: March 2021

Abstract
The purpose of this study was to examine the effect of formulation on microencapsulation of mangosteen peel extract (MPE) on water content and fungus distribution. The treatments tested consisted of: M1 (70% MPE: 30% maltodextrin/MDX), M2 (60% MPE: 40% MDX), M3 (50% MPE: 50% MDX), M4 (40% MPE: 60% MDX), M5 (30% MPE: 70% MDX), and M6 (100% MPE). Each treatment was observed for 0, 2, 4, 6, and 8 weeks. The results showed that the microencapsulation treatment of mangosteen peel extract with maltodextrin (M1 – M5) had a significant effect (P<0.05) on water content and fungus distribution. The water content of the sample starts to increase in the second week and increases with increasing shelf life. The fungal distribution parameters showed the formation of colonies and product damage in the fourth week and continued to increase until the eighth week. This study shows that the microencapsulation treatment (M1-M5) is able to protect the material from environmental influences and can extend the shelf life of the material rather than the control treatment (M6). The M4 treatment containing 40% mangosteen peel extract and 60% maltodextrin showed the best results on the water content and fungus distribution.
Experimental study the effect of surface roughness of a material on its hydrophobicity
Authors: Subagyo Rachmat , Tamjidillah Mastiadi , Irawansyah Herry , Ghofur Abdul , Muchsin  
Published: March 2021

Abstract
To investigate the effect of trapped gas and surface roughness, it is necessary to study more deeply the hydrophobic nature of a material which has a different surface roughness value. This research was conducted experimentally, by first preparing materials that have different grain sizes. Then measuring contact angles, mapping surface roughness, and observing droplets when in contact with the material. This study shows that the increase in droplet volume affects the contact angle formed, the greater the droplet volume the droplet surface tension capability is getting weaker. The smaller the grain size, the higher the contact angle formed, this is due to the particle size that supports the droplet surface, when the particle size is small, the surface tension formed is greater so that the droplet has a high contact angle. Micro/nano size bubbles that spread evenly on the surface of hydrophobic material strongly support the occurrence of hydrophobic properties in a material.
Ballistic limit simulation on commercial medium carbon steel plate with surface hardening using an induction heating
Authors: Purwanto Helmy , Dzulfikar Muhammad , Tauviqirrahman Mohammad , Subagyo Rachmad , Kiryanto  
Published: March 2021

Abstract
Ballistic limit is a speed limit where projectile with a certain shape, angle of attack and size is not able to perforate a target with certain properties and thickness. This paper aims is to determine and analyze the ballistic limit of commercial medium carbon steel plate which has been hardened by induction heating by using finite element based simulation. A plate with a thickness of 8 mm was shot by a deformable blunt projectile with a diameter of 20 mm, a length of 80 mm and a mass of 0.197 kg with an angle of attack of 90° against the plate. Simulation results show that projectile with a speed of 225 m s−1 is still able to penetrate the plate in the form of plugging. The plate can withstand the projectile rate at a maximum speed of 215 m−1. At this speed, the plate is damaged but the projectile does not penetrate. The plate still has ductility properties, as during the simulation there were deflection and bulge in the back side.
Characterization of the γ,α-alumina and its adsorption capability to adsorb nickel (ii) and magnesium (ii) from nickel sulfate as a result of solvent differences
Authors: Fatimah Titin S. , Wahyudi Tatang , Khaerunisa Herni , Saleh Nuryadi 
Published: March 2021

Abstract
This study discusses the characteristics phase of the alumina mixture, namely the γ, α-alumina as well as its ability to adsorb the nickel (II) and magnesium (II) from nickel sulfate due to solvent differences. The γ, α-alumina was synthesized under acidic conditions (pH = 5) from poly aluminum chloride that was calcined at 800 °C by the sol-gel method. The particle size of γ, α-alumina is 15.65 μm; BET specific surface area of 104.12 m2 g−1; mesopores volume of 0.284 mL g−1; and a shape type of IV isotherm curve. Such the characteristic belongs to an adsorbent. The solution of nickel sulfate as Solution (b) has a bigger total adsorption capacity than that of the Solution (a), namely 16.46 mg L−1 and 2.49 mg L−1 respectively. The alkaline buffer formation as the ammonium hydroxide and ammonium chloride in Solution (a) may result in reducing the adsorption capability of the γ,α-alumina. The magnesium concentration of nickel sulfate in Solution (a) is smaller than that of the nickel one, namely 118.36 mg L−1 for the Mg and 486.64 mg L−1 for the Ni. However, the Mg is still more adsorbed around 29.96 mg L−1 compared to the Ni (19.80 mg L−1).
Analysis of corrosion rate at bone implant replacement materials with immersion time variations in simulated body fluid
Authors: Pradityana Atria , Husodo Nur , Ash-Shiddieqy Rizaldy Hakim , Rizal Muhammad Saiful 
Published: March 2021

Abstract
Biomaterials are materials used to replace parts of living systems. 316 L stainless steel has long been used as a substitute material for bone dislocation victims. This research aims to substitute 316 L stainless steel bone implant material with Cr-Ni coated ST 41 carbon steel which has been immersed with varying time-intensity with Simulated Body Fluid. Material testing uses the method of potentiodynamic polarization, electrochemical impedance spectroscopy, and Scanning Electron Microscope. The results of this study are in the form of a comparison of corrosion rate and surface characteristics between 316 L stainless steel and Cr-Ni coated ST 41 Carbon Steel. The immersion time of the material for 12 hours and 366 shows a low corrosion rate with a corrosion rate of 0.0051714 mm year−1 with and 0.001557 mm year−1 for ST41 carbon steel material with Cr-Ni coating, whereas in Stainless Steel 316 L has a corrosion rate value of 0.0029546 mm year−1 and 0.0013166 mm year−1. Surface characteristics show insignificant differences between ST41 steel with Cr-Ni coating and 316 L stainless steel. The results of the study show that Cr-Ni coated ST41 carbon steel material can substitute 316 L stainless steel as a biomaterial in bone implants because it has a low corrosion rate and different insignificant surface characteristics.
Analysis of corrosion rate and surface characteristics in substitution bone implant material with corrosive media simulated body fluid (SBF)
Authors: Pradityana Atria , Husodo Nur , Ash Shiddieqy Rizaldy Hakim , Pamasa Falas Sulthan 
Published: March 2021

Abstract
Bone is a basic part of the human skeletal system which serves as the main foundation of the human skeletal system. and millions of people suffer from bone damage caused by natural diseases or accidents. Bone implants are used to replace, assist or augment diseased or injured biological tissue. One of the medical implants in use today is bone implants. bone implants that are currently commonly used are bone implants with a type of metal material because they have high strength, stiffness, and stiffness. In addition, metal-type bone implants can withstand higher loads than other types of implants. SS 316 L material is often used as a bone implant because it has good mechanical properties and a low corrosion rate. But with a low corrosion rate and good biocompatibility properties, SS 316 L is limited in its use in clinical application. This study aims to find substitute material as bone implants. testing using specimens in the form of ST-41 steel plates coated with Titanium Nitride (TiN) instead of bone implants. Immersion of specimens was carried out with corrosive media in the form of Simulated Body Fluid (SBF) as corrosive media. Testing uses a Scanning Electron Microscope (SEM) to analyze the surface characteristics of the specimen. The results of this study were no damage or apatite coating that protected the surface of the specimen with immersion for 12 hours. While at 336 hours immersion, there is a corrosion point on each specimen. However, the ST-41 steel specimen contained apatite grains on its surface.
Comparison of failure analysis on reheater and waterwall tube power plant base on outer surface
Authors: Drastiawati Novi Sukma , Soekrisno R. , Kis Agustin H.C. , Arsana I Made 
Published: March 2021

Abstract
Visual observation on waterwall tube failure showed crack at the outer surface and fish mouth on reheater tube. An analysis of this research is to compare the causes of failure of waterwall and reheater tube boiler. Method of this used descriptive qualitative with macro and micro visual observation. Crack appeared from the outside waterwall tube occurred at a place attached to the oxide layer, it indicated that failure on this tube achieved in long period. The small crack as a place for new oxide layer and corrosive media. Larger crystal grains at the edge of the oxide layer and tip of crack because the corrosion reaction between oxides and metal, it produces local heat on the area. Failure on reheater tube was presence of scale attached on the outer caused differences in the distribution of temperature between inner and outer surface tube.The dominant factor of this failure occurred intergranular creep fracture. The results shows that main mechanism on waterwall tube failure is physical and mechanical factor on reheater tube.
Effect of bacterial cellulose reinforcement on morphology and tensile properties of starch-based biocomposite
Authors: Suryanto Heru , Pahlevi Ahmad Saifi , Yanuhar Uun 
Published: March 2021

Abstract
This study aims to determine the effect of the addition of bacterial cellulose (BC) from nata de coco to the mechanical properties of the cassava starch-based biocomposite. This study was conducted by a tensile test using a standard specimen of ASTM D-638 type V and fracture morphology using SEM (Scanning Electron Microscopy), using variations in the addition of BC as much as 0% (without additional cellulose), 2.5%, 5%, 7.5%, and 10%. The results showed that the addition of BC to biocomposite could increase their tensile strength and stiffness. Biocomposite with the best mechanical properties was achieved by adding 10% BC to produce tensile strength 19.19 MPa, elongation percentage 10.97%, and modulus of elasticity 173.19 MPa. However, with the addition of higher BC, lower quality bioplastics can also be produced.
Effect of limestone mass concentration on tensile strength and surface morphology of coconut fiber
Authors: Sutrisno  , Soenoko Rudy , Irawan Yudy Surya , Widodo Teguh Dwi 
Published: March 2021

Abstract
The material processing technology was developed to answer the increasing material needs. The material developed is a composite material based on natural fibers. Among many natural fibers and maximum utilization is coconut fiber. This study aims to determine the effect of limestone as a medium for coconut fiber immersion on the tensile strength of a single fiber and the surface morphology of the fiber. Coconut fiber that has been cleaned is soaked in a solution of lime water for 8 hours with a variation of lime content: 0%, 2.5%, 5%, 7.5%, and 10%. Coconut fiber that has been processed is tested by testing a single fiber and SEM. The results obtained from testing a single fiber with 5% limestone content for 8 hours total tensile strength of 236.27 MPa. The tensile strength without treatment, 5% limestone, 7.5% limestone, and 10% limestone are 172,15 MPa, 204.37 MPa, 199.73 MPa and 180.32 MPa. The surface morphology of the fibers with limestone treatment becomes rougher.
Experiment of adding molybdenum to AISI 310 to increase tensile strength
Authors: Permana Diki Ismail , Sumirat Uum , Darwanto Yoko 
Published: March 2021

Abstract
Supercritical coal power plants began in 1983 with 24.1 MPa moisture parameters and 538°C / 538°C temperature (superheated and reheated steam). Ultra supercritical technology began in 1993 with 24.1 MPa and 538°C / 593°C. Starting in 2000, an ultra-high temperature supercritical power plant was built at 25MPa and 600°C / 620°C in Tachibana and Isogo Powerplants. From this phenomenon, together coal at the power plant, there is often damage to the turbine blade because the material from the turbine blade is not able to withstand temperatures> 760°C. So the words between these can be analyzed by adding molybdenum on AISI 310 raw material in order to find a new material that is resistant to temperature > 760°C. Stainless steel is a steel that has an important role in the industry. One type of stainless steel is austenitic stainless steel. In general, stainless steels containing Ni, Cr and no other blends. The strength and tenacity of the austenitic stainless steel can be increased by alloying and thermo mechanical treatment (TMT). In the integration process, a structure can be carried out which can be improved by the mechanical properties of the material. To find out the austenitic stainless steel needs to be developed to increase resistance to the corrosive environment, and also its mechanical properties. This development can be done by combining AISI 310 with Molybdenum
The effect of pure temperature and pressure on alloy hardness of Al-6.7% Cu using squeeze casting method
Authors: Siswanto Rudi , Ma’ruf  , Mukti Adi Marhadi , Subagyo Rachmat 
Published: March 2021

Abstract
Squeeze casting is done by combining the casting and forging processes. The metal solidification process is carried out in a metal mold by pressing it with hydraulic pressure. This study aims to determine the effect of pouring temperature and pressure on the hardness value of the squeeze casting of Al-6.7% Cu alloy material. The process is that the material is melted using a crucible furnace until it melts then poured with a temperature variation of 710 ° C, 730 ° C and 750 ° C. Then it is poured into a metal mold that is heated to a temperature of 250 ° C and then pressed for 60 seconds with variations of 0 MPa, 2.5 MPa, 5 MPa and 7.5 MPa. The test results show that; (1) the higher the pouring temperature, the lower the hardness value, (2) the higher the pressure, the higher the hardness value. (3) The highest hardness value was at pouring temperature of 710 ° C with a pressure of 7.5 Mpa (59 HB) while the lowest hardness value was at pouring temperature of 750 ° C with a pressure of 0 Mpa (34 HB)
Failure mechanism of thermal barrier coating on the first stage turbine blade
Authors: Suwarno  , Muhtadi Handi , Maclauda Isaura F. , Hariyadi Arif 
Published: March 2021

Abstract
One of the main components in a gas turbine for the power plant is the turbine blade. The turbine blade lifetime depends on materials, operation, and maintenance. A prominence reason for accelerate turbine blade degradation is caused by the failure of the thermal barrier coating (TBC). In the present work, we studied the failure of TBC on the 1st stage turbine blade. A scanning electron microscope, optical light microscope, and X-Ray diffraction were used for samples examination. The analysis results showed that the TBC of first stage turbine blades is a plasma-water type sprayed and consists of 7 wt. % yttria-stabilized zirconia (YSZ). Mechanism of separation in the TBC layer is caused by thermal fatigue due to thermal differences expansion between the TBC and the thermally grown oxide (TGO), thereby causing tensile stress and compression on the TBC. The pressure causes micro-cracks on the top coat lead to the separation of the TBC top coat.
The influence of flux type and scrap size on recycling yield of Al drink cans
Authors: Risonarta Victor Yuardi , Anggono Juliana , Nugrowibowo Setyo , Kristoforus Alexander 
Published: March 2021

Abstract
Aluminium is widely used as a beverage can due to its excellence properties, i.e., good deformability; excellent corrosion resistance, high strength to weight ratio and non-toxic. The global consumption of canned drinks in 2017 was estimated at approximately 200 million pieces annually. These aluminium cans should then be recycled to minimize environmental challenges. Challenge, however, exists to optimize the recycling process. In this work, size of recycled cans, flux type, and recycling temperature were investigated to achieve higher recycling and Al yield. After various flux compositions were attempted to increase the recycling and Aluminium yield, the most suitable flux material was a mixture of chloride, fluoride, and SO4. Meanwhile, when the scrap dimension reduced to 1 cm2, the recycling and Aluminium yield showed no significant differences with the yield obtained using a scrap dimension of 4 cm2.
Diagnosis of Age Related Macular Degeneration by Curve Fitting RPE Layer
Authors: Pavithra D , Vanithamani R , Karolinekersin E 
Published: March 2021

Abstract
Optical Coherence Tomography (OCT) of the retina allow high resolution and non-invasive imaging for diagnosis of macular diseases such as Age Related Macular Degeneration (ARMD). The aim of this work is to suppress the speckle noise, segment the retinal pigment epithelium layer and identify the possibilities for diagnosis of ARMD by curve fitting method. Speckle pattern, which is multiplicative in nature, degrades the quality of OCT images. Bilateral and homomorphic-wavelet filters are adopted to minimize the speckle noise in OCT images. The performance of these filters is tested on a set of OCT images collected from an open source database. The experimental results prove that homomorphic-wavelet filter is better in reducing the speckle noise. Structural changes of retinal pigment epithelium layer, a key factor of ARMD, is identified by Graph-based method, which is utilized further in diagnosis of ARMD by curve fitting method. The sum of squares due to error (SSE) values of ARMD images are very higher compared to normal images, which can be used as a feature for diagnosis.
Machine Learning Techniques for Recommender Systems – A Comparative Case Analysis
Authors: Thomas Binu , John Amruth K 
Published: March 2021

Abstract
Recommender System (RS) is one of the most popular applications of Artificial Intelligence which attracted researchers all around the world. Many machine learning algorithms are used to develop RSs. Choosing the best machine learning algorithm to provide users with a product or service is the most challenging task in the area of RSs. Now we are witnessing a paradigm shift in the purchase habits of people from in-shop to online resulting in the availability of online information exponentially growing every day. The ever-increasing online information and the number of online users create new avenues in RS. In an online shopping scenario, these systems must be able to recommend relevant items to the users. The RSs have to deal with the huge amount of information by filtering the relevant information based on the analysis made on the inputs made by the users during their online sessions. These systems can recommend appropriate items to users based on their interest and previous preference which can lead to increased sales. The three major techniques used to build a RS are content-based, collaborative based and hybrid-based. This paper presents the various applications of RSs and makes a detailed comparative study of different machine learning approaches used. The methodologies used for identifying research articles for analysis, the merits and demerits of different techniques in RSs and domain-specific applications of these techniques are well explained here with scientific review analysis.
Performance Analysis of Circular Shape Microstrip Antenna for Wireless Communication System
Authors: Kannadhasan S. , Nagarajan R. 
Published: March 2021

Abstract
In this paper proposes a broad band circular strip antenna based on numerical techniques. For the operating frequencies, a circular patch antenna is installed on FR-4 substrate material 4.2. The proposed antenna uses the finite element method to design an operating frequency from 2GHz to 10GHz. Substrate height is 1.6mm. The circular patch has a circumference of 8.82mm. The antenna displays good output below -16dB is the return loss value and the antenna gain is obtained in the range from 2.4dBi to 10.02dBi. The proposed circular patch antenna is designed and analysed the various parameters like VSWR, Gain, Return Loss, Directivity and Radiation pattern.
Implementation of Multivariate Logistic Regression Model for Cerebral Palsy Identification using Prenatal, Perinatal Risk Factors
Authors: Muthureka K. , Srinivasulu Reddy U. , Janet B. 
Published: March 2021

Abstract
Cerebral Palsy (CP), a static, neuro and motor disorder caused by brain injury in the time period of prenatal, perinatal and postnatal, is the major developmental disability affecting children’s function. Children with CP in children cannot be curable but quality of life can be improve with the help of treatment such as surgery and therapy. Early identification is important to the CP children for starting the treatment. There are numerous Machine Learning (ML) algorithms used in health care for prediction and classification. One of the ML algorithms called Logistic Regression which is used for binary classification using univariate and multivariate. This study, is of interest to enable early identification of CP using prenatal and perinatal risk factors with help of Multivariate Logistic Regression.