bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of hydroxyapatite by cytotoxicity test and bending test
Authors: Sirait M , Sinulingga K , Siregar N , Doloksaribu M E , Amelia  
Published: February 2022

Abstract
Hydroxyapatite has been synthesized as a bone graft material by analyzing the membrane made according to the cytotoxicity test and bending test. The method used is dry ball milling. Cytotoxicity testing was carried out by making isolated osteoblast cells cultured in a 75 cm2 cell flask containing a minimum of essential media. Based on the cytotoxicity test, it was found that hydroxyapatite is not toxic with cell viability above 60% (non-toxic requirements ISO 10993-5). From the variation of the hydroxyapatite mixture used, the average cell viability was (100.48 ± 11.98)%. A mixture of 2.5% Ag and 5% Ag with hydroxyapatite also provides good viability, which is above 60%, which means it is not toxic. The results of the analysis of the bending test and the compressive test showed that the larger the hydroxyapatite mixture, the lower the bending and compressive test results. The maximum bending test on a 10% mixture is 22.1 M.Pa and the compressive test on a 5% mixture is 16 °ShD.
Rolling uphill experiment – a close look and explanation
Authors: Wirjawan Johannes V.D. , Founda Noviani Elisabeth Pratidhina 
Published: February 2022

Abstract
Rolling uphill experiment is one of fascinating experiments that easily attracts students’ attention due to its contradictory with common sense. Although it has been explained qualitatively, explicit explanation of the phenomenon is hardly found. In this study the researchers will describe the detail setting of the experiment and quantitatively set the formula to ascribe the relationship amongst the involved variables which allow the rolling uphill happens. It turns out that the relationship among the involved variabloes is a simple one and can be easily understood.
The use of thermo electric generator to utilize the waste heat from the biomass stove into electricity
Authors: Tambunan B H , Simanjuntak J P , Koto I 
Published: February 2022

AbstractIndonesia has a huge potential for biomass energy resources. In 2013, the estimated potential of forest biomass in Indonesia for bioenergy was 132 PJ, 50.4% from harvest residues and 49.6% from wood processing residues. Until now, the technology of burning biomass using a stove continues to develop. Biomass stoves are designed, modified and tested to get maximum performance, at least approaching the performance of LPG-fueled stoves. Several studies concluded that about 14.66% of the total heat loss is on the walls of the biomass stove. The purpose of this study was to investigate whether the waste heat in the wall of a biomass stove can be used to generate electricity. Many researchers have studied the heat loss on the walls of the biomass stove, this heat loss can reduce the thermal efficiency of the stove and can cause the stove user to feel uncomfortable. Based on the Seebeck effect method where the temperature difference can be converted into electricity. If there is a temperature difference between the two sides of the thermoelectric, electricity will arise. This principle is used by thermoelectric generators. To maximize the temperature difference, the cold side of the Thermoelectric Generator (TEG) needs a cooling system. In this study, the TEG was attached to the wall of the biomass stove, then the voltage generated by the TEG was measured for each type of biomass fuel. the highest average voltage produced by wood chips, followed by candlenut shells, corn cobs and coconut shells. This is unique, although the calorific value of coconut shells (19,5 MJ/kg) is higher than hard wood (18,8 MJ/kg) and corn cobs (5.32 MJ/Nm3), but the highest average voltage is produced by wood 1.30 volts, then 1.12 volts of candlenut shells, 1.08 volts of corn cobs, and 0.79 volts of coconut shells.
Microplastic waste polluted water measurement development based on parameter of physics
Authors: Indrasari W. , Sakinah F. , Umiatin U. 
Published: February 2022

Abstract
Currently, microplastics are detected in almost all water areas of the world. Hundreds of tons of microplastic waste produced and disposed of in the waters impact tissue damage and reduce water quality. A measurement system for detecting water polluted by microplastic waste based on the parameter of physics has been developed. This developed system is composed of a water pH sensor, salinity sensor, conductivity sensor, magnetic sensor, and Arduino Uno as the control system. The sensor characterization was carried out using standard tools to determine the sensitivity of each sensor. This process found that the sensitivity of the water pH sensor, water conductivity sensor, magnetic field sensor, and salinity sensor was -0.1702 V/pH, 0.9 mV/ppm, 0.0018 V/Gauss, and 0.1905 V/PPT, respectively. The prototype measured these parameters in synthetic wastewater and natural water samples contaminated by microplastic waste. Synthetic wastewater is a mixture of water, salt, and scrub with different concentrations. Meanwhile, the natural sample water originates from seven rivers around the Jakarta area. This system is equipped with an HC-06 Bluetooth module to transfer measured data to the Android application to be monitored directly by the smartphone..
Prototype of water level monitoring system using magnetic sensor and ultrasonic based on Arduino Mega 2560
Authors: Indrasari W , Kadarwati L V 
Published: February 2022

Abstract
Water level monitoring is an activity to observe the water level by identifying and anticipating flood problems that will arise for action to be taken as early as possible. This system is connected by water level measurement. This prototype uses two types of sensors to measure the water level, the UGN3503 magnetic sensor will detect the water level horizontally, and ultrasonic sensors will detect vertically. Arduino Mega 2560, as a control system, regulates the work of the integrated sensors. The experiment using one UGN3503 sensor is obtained the maximum deviation on the addition or reduction of water by 3 mm. The overall system experiment shows that the measurement results of the UGN3503 sensor are closer to the actual height than ultrasonic. The data region affected by the water overflow is processed in ArcGIS software to predict that area. The relationship between height alterations to the overflow area is described in a linear equation.
Evaluation of trashrack replacement design for malalo intake of singkarak hydro power plant in west Sumatera
Authors: Kurniawan Elfin , Simaremare ArionmaroAsi 
Published: February 2022

Abstract
Singkarak hydro power plant (SHPP) with the capacity of 175 MW provide essential supply to Sumatera Interconnection System thus reliable and efficient operation of the hydro power plant component must be maintained. With the damaged experienced by the trash rack during Padang earthquake, the operation of the power plant was disturbed and replacement of trash rack need to be executed. This study evaluate the modification of trash rack replacement in terms of head loss, potential energy and revenue losses. This simple evaluation finds that the replacement design gives lower head loss which translated to lower energy and revenue losses. The potential energy and revenue losses also increase exponentially with the increase of trash rack blockage. This result amplify the importance of trash rack design and cleaning during operation of a hydro power plant.
Impact of the HFC migration to FTTH on the efficiency and reliability of the internet provider services business (A case Study)
Authors: Khalil  , Siregar Marsul , Sihombing Denny 
Published: February 2022

Abstract
This paper presents the impact on the efficiency, reliability, and quality of the Internet provider services due to the migration of the Hybrid Fiber Coaxial (HFC) to the Fiber To The Home (FTTH) infrastructure. The implementation of the emerging technology on communication caused an increase in the internet service provider business competition and it makes the company that engaged in this field will compete to provide the best service to the customers as especially on the efficiency and reliability of the services to whom using the FTTH. The comparison and analysis of the impact of the HFC stand-alone to the FTTH technology migration process on both of the customers sides as well as the Network Availability and the percentage of uptime (connection to the ISP’s) of customer devices are provided. In this case study, it is found that the infrastructure cost of the technology HFC system is cheaper about 53.93 percent than the technology FTTH system. However, from a reliability perspective, FTTH is much better than HFC. It is found that the impact of the migration from HFC to FTTH shows the yearly Network Availability was 98.635 percent with a downtime of 2,819,473 minutes. And it provides an increase of Network Availability after construction (during commissioning or acceptance test). In addition, it was found that the correlation between uptime/downtime before migrating during employed the HFC technology, there were many problems caused by power supply problems and high losses of the coaxial cable. So if the coaxial cable is replaced by the fiber optic cable, will be there is an increase in the availability of the Network Availability during 2020 by 1.301 percent. Also by takeout the FDT on the FTTH, it is predicted that the cost reduction about 10 percent, faster implementation for the schedule and fewer cables maintain.
Motion control development for autonomous ground robots in agriculture task
Authors: Latif M. , Hardi Shofia , Herawati Sri 
Published: February 2022

Abstract
Motion control for autonomous ground robots to solve tasks in agriculture is investigated in this study. Motion control is designed and developed to track the reference trajectory. The model is developed in detail based on the kinematics and dynamics of the robot. The novelty of this research is to solve the problem of controlling agricultural robots on the problem of tracking a rectangular spiral trajectory. The motion controls described in this study were developed and validated in a simulation. Accuracy of the developed system is validated by measuring the error tracking using MSE and RMSE. Conclusion shows that the developed motion control for autonomous ground robots works well based on the validation results.
Development of PISA-based test on mechanical wave material in senior high school
Authors: Baiziah Destri , Sahyar  , Derlina  
Published: February 2022

Abstract
This study aims to develop a PISA-based test on mechanical wave material in high school in accordance with good test qualification standards in terms of validity, reliability, level of difficulty, discriminatory power and effectiveness of distractors. The type of research is development research, using the ADDIE model. The data analysis technique used is qualitative and quantitative. The results of qualitative analysis, the quality of the PISA-based test is very good with a percentage of validity of 84.75% based on the results of validation by 5 experts who are reviewed in terms of material, construct and grammar. Quantitative analysis of the quality of the PISA-based test are good. Analysis of 38 items in the small group test obtained 36 items accepted and 2 items rejected. The large group test obtained: (1) 32 valid items (88.89%), 4 invalid items (11.11%). (2) the reliability of the tests is included in the Very Good category with a value of 0.839. (3) 4 (11.11%) questions in the easy category, 30 (83.33%) questions in the medium category and 2 (5.56%) in the difficult category. (4) The discriminatory power of questions obtained 1 (2.78%) questions in the very good category, 31 (86.61%) questions in the good category and 4 (11.11%) questions in the bad category. (5) 32 (88.89%) items are effective and 4 (11.11%) items are ineffective. The items received were 30 (83.33%) questions, 2 (5.56%) items revised, and 4 (11.11%) items rejected.
Development of teaching materials like PISA for physics mechanical wave topic in high school
Authors: Fonna Nurdianita , Bunawan Wawan , Derlina  
Published: February 2022

Abstract
This study aims to describe the validity, practicality and effectiveness of physics teaching material like PISA. The method carried out in this study uses Research and Development (R&D) development research using the ADDIE model consisting of 5 main phases or stages, namely 1) Analyze (Analysis), 2) Design (Design), 3) Develop (Development), 4) Implement (Implementation), 5) Evaluate (Evaluation). Physics teaching materials developed in the form of teaching materials like PISA. The subjects in this study were students of class XI MIA I SMA Swasta Dharma Pancasila Medan. The results of the study obtained that the validity of teaching materials to the material by the validator obtained results from the content feasibility aspect of 88%, the language feasibility aspect by 86% and the presentation feasibility aspect by 87% while the validity of the teaching materials to the media by the validator obtained a result of 87% so that it met the category valid. The results of the effectiveness test show that teaching materials are effective for use in the learning process with a percentage value of 82% with a very effective category. The practicality of teaching materials in the very practical category of student responses obtained a percentage value of 90%. This shows that the physics teaching materials like PISA have met the valid, practical and effective criteria. And there is an increase in student learning outcomes in the good category after applying high school physics teaching materials like PISA.
Analysis of momentum and impulse on students’ creative thinking skill through project based learning integrated STEM (science, technology, engineering, mathematics)
Authors: Saputri Mawarni , Syukri Muhammad , Elisa  
Published: February 2022

Abstract
The aim of this study was to analyze students’ creative thinking skills on momentum and impulse material through Project based learning integrated STEM. The type of research used is a quasi experiment. The data analysis was carried out through ten creative thinking skills test in essay form. Before instrument test are tested on students, expert validation tests were carried out first. The creative thinking skill test indicators used consist of fluency, flexibility, originality and elaboration. The results of the study showed that the average value of students’ creative thinking skills are classified as creative category. Average percentage of students’ creative thinking skills scores for each indicator obtained are the lowest indicator is originality, while the highest indicator score is fluency. The implementation of Project based learning integrated STEM has a positive impact in improving students’ creative thinking skills especially in physics learning.
Interactive learning media innovation using lectora inspire solubility and solubility product materials
Authors: Lukman I , Silalahi A , Silaban S , Nurfajriani  
Published: February 2022

Abstract
This research aims to determine the feasibility level of interactive learning media using lectora inspire material solubility and solubility product which was developed based on the BSNP standard integrated interactive media. This type of research uses the Research and Development (R & D) method with the Analysis, Design, Development, Implementation, Evaluation (ADDIE) model. The instrument used is an interactive media integrated BSNP questionnaire given to one lecturer of technology science, one lecturer of chemistry education, and one high school chemistry teacher. The data was processed using descriptive statistics. The results showed that interactive learning media using lectora inspire material solubility and solubility product which was developed was very feasible to use reffering to the BSNP standard integrated interactive media with content feasibility of 4.8, and presentation feasibility of 4.9. This research was carried out only until the development stage.
The effect of reflector application for solar panel output improvement
Authors: Bintang Salman , Muhammad Aulia Rahman S , Sinaga Denny Haryanto , Dewy Mega Silfia , Tarigan Rizky Falmi Setiawan , Marpaung Paulinson Riki 
Published: February 2022

AbstractThe potential of solar energy as a renewable energy source is widely available in nature. Sunlight is abundant and even for tropical countries, the sun shines almost all year round. Therefore, solar power plants are very suitable for application in Indonesia. Solar electrical energy is generated by components called solar panels. This component converts energy from sunlight into electrical energy. Solar Reflector used in solar panels is a mirror. A plane mirror is a mirror that has a flat surface like a straight line, where one surface is coated with a reflecting metal so that the surface of the flat mirror can reflect more than 95 percent of the light that hits it. In this research, reflectors were added to the solar panels on the right and left sides. The reflector on the solar panel is shaped at an angle of 70 degrees. The reflector serves to optimize the light around the solar panel and focus the light towards the solar panel so as to produce greater output power. The highest voltage and watt are at 11.00 AM. 27 July 2021 is good condition for solar panels with average 19.63 V and 56.81 W.
Utilization of pineapple (ananas comosus l) leaves plant waste as a natural biosorbent
Authors: Herlinawati H. , Sihombing Junifa Layla , Kembaren Agus , Masdiana  
Published: February 2022

Abstract
The adsorption process is more suitable because the costs required are not too expensive and will not cause new contaminants. Currently, research is being promoted on the use of alternative adsorbents derived from nature. Natural adsorbents in addition to having good adsorption ability, are also more economical. Natural biosorbent from pineapple leaves (Ananas comosus L) which had previously been carried out with carbonation, biosorbent activation, and biosorbent characterization using XRD and BET instruments, respectively. The results of the XRD analysis characterization obtained the diffraction pattern of pineapple leaves carbon, there are several sharp peaks, which are very clear at a diffraction angle of 2θ between 25 to 65 degrees, with a crystallinity degree of 32% and pineapple leaves activated carbon, increased the number of degrees of crystallinity at a diffraction angle of 2θ between 20 to 65 degrees, with a degree of crystallinity of 42.26%. The results of the XRD analysis characterization showed that pineapple leaves biosorbent and pineapple leaves activated carbon had amorphous material structure. This material is composed of atoms that are arranged irregularly and randomly scattered. The results of the BET analysis characterization obtained that each graph meets the classification of type I, type II, and type V adsorption isotherms, it means that these carbons have the same type, namely micropores (< 2nm). The surface area according to BET data on pineapple leaves carbon was 70,418 m2/g and carbon activated had an outer surface area of 39,394 m2/g. Likewise with the results of BJH data, where the surface area of pineapple leaves carbon is 44,775 m2/g higher than carbon activated is 25,685 m2/g.
Industrial field work practice information system design
Authors: Syahputra Fahmy , Dalimunthe Amirhud , Sidabutar Uli Basa 
Published: February 2022

Abstract
The Faculty of Engineering, Universitas Negeri Medan requires the development of technology and communication in assisting performance and processes in carrying out their functions. Its development must produce benefits for the Faculty so that academic implementation runs smoothly, as well as assisting organizations in carrying out the required processes to help organizational managers make decisions. Changes in the form of the process used with the development of technology and communication are expected to encourage organizations to have better management.
Control optimal analysis of SEIR model of covid 19 spread in Indonesia
Authors: Rangkuti Y.M. , Firmansyah  , Landong A. 
Published: February 2022

Abstract
In this paper we use optimal control techniques, SEIR model of Covid 19 in case Indonesia, in order to establish vaccination, personal protective measures and treatment plans to control the spread of an infectious disease. We validate them by the use of the Maximum Principle. The findings revealed that the best practice of combining all three intervention measures considerably reduces the proportion of people who are exposed and symptomatic, as well as those who are asymptomatic.
Focal intensity landscapes of tightly focused spatially varying bright ellipse fields
Authors: Pal Sushanta Kumar , Kumar Singh Rakesh , Senthilkumaran P 
Published: February 2022

Abstract
Vector vortex beams play an important role in tailoring tightly focused fields by creating an additional longitudinal component at the focal plane. Until now, mainly focusing properties of fundamental, higher order vector fields and negative indexed ellipse fields have been investigated. In this paper we numerically analyze tight focusing behaviour of ellipse fields embedding C-point singularities of index

I
C

=
±

1
2

,

I
C

=
±
1

,

I
C

=
±

3
2

and

I
C

=
±
2

. We show that both the sign and absolute value of C-point index (I

C
) of the ellipse fields play an important role in tailoring the focal intensity landscapes. For negative index C-points the intensity distribution of the longitudinal components show symmetries that correspond to the number of separatrices present in the polarization distribution. At the focal plane, both transverse and longitudinal components of the ellipse fields are found to be embedded with phase singularities. These ellipse fields can be useful in advanced microscopy for shaping the focus of light fields for various applications.
The integrated contribution of surface topology to anti-icing effectiveness
Authors: Truong Mai Xuan , Hanh Vu Thi Hong , Nguyen Thanh-Binh 
Published: February 2022

Abstract
The effects of topology parameters at micro-scale on anti-icing performance have not been investigated theoretically and clearly. In this work, we figured out the affection of structure parameters and derived quantities to anti-icing performance in terms of adhesive strength. Well-textured silicon microstructure with different topologies and surface energies was generated via the lithography process. The parameters including pillar height, top diameter, and spacing were simultaneously investigated through the transition energy barrier approach. The results demonstrated the integrated contribution of all parameters in anti-icing performance, instead of independent effects. Furthermore, our results disclosed the correlation contribution of edge and top effects in adhesion strength. This insight should lead to an understanding of icing phenomena and the design of icephobic surfaces.