bluuebunny/crossref_metadata_2025 huggingface dataset:
Calibration for Instrument Argumentation Skills on the Subject of Fluid Statics Using Item Response Theory
Authors: Affandy Harry , Arya Nugraha Dewanta , Nourma Pratiwi Scundy , Cari C.
Published: March 2021

This study aims to calibrate the instrument of argumentation skills on the subject of Fluid Statics using item response theory (IRT). The blueprint instrument developed based on the aspects and sub-aspects of argumentation skills, totaling 20 items. The scoring uses the Partial Credit Model (PCM) principle in 4 categories. Subjects involved in the study were 206 undergraduate students at two different universities. The validation of the instrument using expert judgment techniques, which consisted of linguists, physicists, and educational measurement experts. Instrument calibration for argumentation skills is carried out by (1) analysis of item fit with PCM by testing goodness of fit items, (2) testing prerequisite analysis, (3) reliability, (4) difficulty level, and (5) Standard Error of Measurement (SEM). The test developed is valid with Aiken V index values in the range 0.93 to 1. The analysis of IRT assumptions uses two parameters, the adequacy test of the sample and the factor analysis. The Chi-Square value in the Bartlett test is 2202.67 with df 190, and a p-value value (Sig.) <0.05 indicates that the sample size used has met the unidimensional requirements. The instrument developed has met the criteria for scoring the Polytomus items, based on a) the MNSQ INFIT value is in the range of 0.70 to 1.30, and b) the difficulty index test is in the range -2.00 <b <2.00. The results of the reliability estimate on the test equipment obtained a reliability value of 0.86, which means that the reliability of the test is in the high category. The graph of the information function and SEM converge on the ability scales of -2.8 and +1.5, meaning that the skills test kit argues it is suitable for testees in the low to moderate ability range.
The Development of HOTS-Based Mathematics Teaching Materials in Elementary School
Authors: Nurlaily Vivi Astuti , Sholihah Husna Imro’athush , Wulandari Rizki Ayu , Sa’diyah Arifatus
Published: March 2021

Teaching material is one component that occupies an important role in the learning process. Teaching material with HOTS component will be able to clearly distinguish ideas or ideas, argue well, be able to solve problems, be able to construct explanations, be able to hypothesize, and understand complex matters more clearly. The research aims to produce valid, practical, and effective HOTS-based mathematics teaching materials in elementary schools. The research type is research and development (R&D). The subjects of this study were students and teachers of SDN 4 Ngawen Blora. Data collection techniques used were interviews, questionnaires, and tests. The research result presented is based on the results of limited trials. To this research, it was found that the average mathematics learning achievement increased from 57.50 to 86,50. The prototype of HOTS-based mathematics teaching materials that was developed has shown good results with a percentage of assessment by the teacher of 95.45%. Students show an interest in HOTS-based mathematics teaching materials. Students feel challenged by the activities and learning activities presented. However, a few things need to be fixed, that is unclear pictures of the presentation aspect to students. Additionally, the teacher also provides suggestions and input on improvements to the HOTS-based mathematics teaching material prototype. The suggestion given includes replacing unclear images and providing explanations that match with the image, enlarging the image size that contained in the prototype, and correcting typographical errors. Moreover, the revised prototype results will be used in further trials.
Developing HOTS-based Model to Improve Mathematical Problem Solving Skill of Elementary School Teacher Education (PGSD) Students
Authors: Nurwulandari Ika , Rofiq M Aunur
Published: March 2021

The purpose of this development research is to produce Higher Order Thinking Skill (HOTS)-based pre-service training model for students of PGSD Study Program of STKIP Muhammadiyah Blora who take Mathematics I courses. The teaching materials are in the form of HOTS-based teaching materials and evaluation questions to measure students’ mathematical problem solving abilities. Teaching materials developed meet valid and effective criteria. This type of research is development research following Borg and Gall procedures. This research leads to the improvement of students’ mathematical problem solving abilities after applying Mathematics based on Higher Order Thinking. In addition, through this teaching material, students become accustomed to high-level thinking so that they are able to solve any mathematical problems given even the average student’s mathematical problem-solving ability was increased from 57.50 to 87.90. Thus, the development of HOTS-based mathematics learning modules can improve students’ mathematical problem solving abilities.
Analysis of Changes in Forest Health Status Values in Conservation Forest (Case Study: Plant and Animal Collection Blocks in Wan Abdul Rachman Forest Park (Tahura WAR))
Authors: Safe’i Rahmat , Darmawan Arief , Kaskoyo Hari , Rezinda Citra Farshilia Gayansa
Published: March 2021

Data and information on the health condition of conservation forests can be obtained by periodically monitoring forest health. Forest health monitoring is intended to monitor, assess, and report on the current status, changes and long-term trends in the health of forest ecosystems. This study aims to obtain changes in the value of the status of conservation forest conditions. The location of this research is in the Wan Abdul Rachman Forest Park (Tahura WAR) in the plant and animal collection block area. This study used the Forest Health Monitoring (FHM) method with a sample measuring plot in the form of six FHM clusters. The stages of this research are making measuring plots, monitoring forest health, and assessing the health of conservation forests. The results showed that the change in the value of the status of the health condition of conservation forests was that the cluster plots 1, 2, and 5 had changed and the cluster plots 3, 4, and 6 did not change. Thus there is a change in the value of the health status of conservation forests which tends to be better.
The Conceptual Framework for Problem and Research-Based Learning (PRBL) Model in Learning The Natural Sciences to Empower Students’ Analytical Thinking Skills
Authors: Suyatman  , Saputro Sulistyo , Sunarno Widha , Sukarmin
Published: March 2021

Analytical thinking skills are part of critical thinking skills and higher-order thinking skills that are the demands of students in the 21st century. This study aims to produce a conceptual framework for a model in science learning to empower students’ analytical thinking skills. The method used in this study was a qualitative method, with the primary source was literature review. Data collection techniques employed literature study which collected data through books and journals. The data obtained from the literature were collected and processed by editing, organizing, and finding the results. Data analysis in this research was content analysis to analyze in-depth the contents of the literature being studied. The results of this study consisted of: 1) The conceptual framework of the modified science learning model is called the problem and research-based learning (PRBL) model, 2) The modified PRBL model has the potential to empower students’ analytical thinking skills. This study illustrates to lecturers and subsequent researchers that the modified PRBL model demonstrates the potential to empower analytical thinking skills. The researcher suggests the next researchers conduct research on the application of the PRBL model in the field to test the validity and practicality of the model.
Exposure Factor Control with Exposure Index Guide As Optimizing Efforts in Chest Pa Examination
Authors: Irsal Muhammad
Published: March 2021

Participation between radiographers and medical physicists is needed in optimizing efforts to control the selection of exposure factors by the required clinical radiographic examination. This research is descriptive quantitative by analyzing of exposure index results used in the chest PA examination as an effort to optimizing radiation dose. Also, statistical analysis was carried out to determine the relationship between exposure and the exposure factor using the Spearman test. Results the Spearman test results for underexposure to kV 0.207, and mAs 0.012, meanwhile for overexposed to kV -0.283 and mAs 0.166, the radiographer can make efforts to optimize radiographic examinations by considering the optimal selection of exposure factor parameters which can use a combination of exposure index by assessing the deviation index indicator and maximizing use post-processing or windowing to improve image quality.
The Development of a Four Tier-Based Diagnostic Test Diagnostic Assessment on Science Concept Course
Authors: Fakhriyah F. , Masfuah S.
Published: March 2021

A learning success could be seen from the material mastery and conceptual understanding inculcation obtained by the students. To find out how students’ misconceptions occur, it could be done by developing a diagnostic assessment. This research aims to develop and describe the instrument validity of the four-tier diagnostic test for diagnosing misconceptions by the Primary School Teacher Education program of Universitas Muria Kudus on Science Concept course. This research applies the Research and Development design. It consists of a preliminary study, diagnostic test development, and diagnostic test validation. This article discusses the development and four-tier diagnostic test instrument validation results. The developed instrument consisted of 40 question items. They were Physics and Biology materials. The validation stage involved content and face validities. The expert judgment results showed an average score of 93.09, with very valid criterion. Thus, the four-tier based diagnostic test was valid and could be implemented. The reliability calculation obtained the r-count score = 0.698, while the r-table score = 0.514. The r-count is higher than r-table, then the instrument was reliable. It showed that the instrument was valid and reliable and could be implemented for the students of Primary School Teacher Education. Based on the validation result, the Four-Tier based diagnostic test was valid and reliable to apply for diagnosing the students’ misconceptions in science concept course.

Faculty of Universitas Muria Kudus that allowed us to conduct this research. Thanks to the executive team for assistance.
The Building of Students’ Problem Solving Skills through STEM Aproach with Virtual Simulation Media
Authors: Parno  , Anggraini R T , Hidayat A , Fauziyah S , Pramono N A , Supriana E , Ali M
Published: March 2021

The problem solving difficulty level of the topic of optics is ranked number two among other topics in physics, but the solution to this situation by implementing STEM approach with Virtual Simulation Media (VSM) in Problem Based Learning is still rarely done. This study aims to develop students’ problem solving skills on the topic of optical instrument through PBL-STEM with VSM learning. The type of this research is a quasi-experimental with Pre-and Posttest Design, involving grade XI students in Malang, Indonesia. There are experiment and comparison classes, which received, respectively, PBL-STEM with VSM and PBL learning models. This study uses The Optical Instrument Problem Solving Skills Test with the alpha Cronbach reliability of 0.83. Data were analyzed using the Mann-Whitney U test and independent sample t test, N-gain, and effect size. The results showed that the students in experimental class had significantly better problem solving ability than the students in comparison class. PBL-STEM with VSM class has N-gain in medium category, while PBL class has low category. The two classes had the highest increase in the “useful description” step and the convex lens subtopic, and the lowest increase in the “logical progession” step and the telescope and camera subtopics. The PBL-STEM with VSM class has a practical effect of the “very large” category toward the PBL class in building problem solving skills. Therefore, research of Experiment-Comparison class pair is recommended to be widely implemented in schools as an effort to improve problem solving ability of student.
The Study on Factors Affecting the Synthesis of Methyl Ester Sulfonate from Palm Oil using CaO Catalyst with Microwave-Assisted
Authors: Sahila S , Qadariyah L , Mahfud M
Published: March 2021

Methyl ester sulfonate can be synthesized from palm oil using sodium bisulfite as a sulfonating agent with microwave-assistance as a heating energy source. The use of microwave as an energy source can reduce the reaction time and increase the product. Methyl ester sulfonate can be produced in several stages, that is transesterification, sulfonation, purification, and neutralization. The transesterification process was carried out by reacting palm oil and methanol with a mol ratio of 1:9 and 1%wt of KOH catalyst at a microwave power of 300 watts, and a temperature of 60°C for 10 minutes. Methyl ester was sulfonated using sodium bisulfite at a power of 300 watts for 40 minutes at a temperature of 80°C-100°C. This process also used a CaO catalyst of 1.5% and the mole ratio of methyl ester:NaHSO3 is 1:2. The resulting methyl ester sulfonate was then purified by the addition of methanol and heated in a microwave power of 300 watts, at temperature 55°C for 10 minutes and then neutralized with NaOH. The resulting methyl ester sulfonate has a density of 0.8626 gr/ml, viscosity of 3.51 cSt, pH of 1.68, yield of 98.67%, and surface tension of 32.23 dyne/cm.
Transesterification of Kapok Seed Oil (Ceiba Pentandra) Into Biodiesel Using Natural Zeolite Catalysts
Authors: Sunarti A.R. Yelvia , Roesyadi Achmad , Kurniawansyah Firman
Published: March 2021

Impact due to the depletion of fossil-based petroleum reserves and high level of air pollution due to exhaust emissions from the use of fossil fuels, it is necessary to further develop renewable energy sources. This research carried out the development of the transesterification process of kapok seed oil (Ceiba pentandra) into biodiesel using natural zeolite catalyst of Tasikmalaya. In this study, natural zeolite was modified by chemical activation and calcination at temperature 450°C using furnace. Spectrophotometric analysis of the natural zeolite showed the Si/Al ratio before modification was 0.2542 and after modification, it increased to 0.3339. X-Ray Diffraction showed the presence of Si phase at angle 27° with an intensity of 100% and Al phase at angle of 48° with an intensity of 12%. Brunauer Emmet Teller analysis showed the surface area of the natural zeolite catalyst was 699,820 m2/g. The transesterification process was carried out by reacting kapok seed oil with methanol at ratio of 1: 3, 1: 6 and 1: 9 and reacted at temperature of 50°C, 60°C, 70°C, and 80°C with percent catalyst 5% by weight of oil. The highest biodiesel yield was obtained at operating conditions 60°C with mole ratio of 1: 9 which was 67.90%. The FAME content contained in biodiesel was dominated by ME linoleic at 64.94%, ME oleic by 15.87% and ME palmitate by 14.84%.
Implementation of Industrial 4.0 Library Based on Mobile using QR-Code
Authors: Lestariningsih T , Afandi Y , Kusbandono H , Syafitri E M , Winarno B , Phonistyawati A , Atmaja A P , Suhasto R B I N
Published: March 2021

Libraries are an important element in the world of education so that libraries need to innovate by collaborating library services with technology. AR is the concept of combining virtual objects with real objects that are used to display interesting library service information so that it can improve library performance in providing information to people in need. The purpose of this study was to implement AR using QR-code to facilitate users in terms of college library collection services. In the development of multimedia research methodology, there are six stages, namely 1. concept 2. design 3. material collecting 4. assembly 5. testing 6. Distribution. These six stages can be carried out in an irregular manner, so that the stages of multimedia development can swap positions. But for this stage there is one stage that must be the first thing to do, namely the concept stage. The result obtained is the implementation of AR by using QR-code for library services such as library plans, bookshelves and book synopses in universities.
Android Based Emergency Button with Position Share System
Authors: Setia L D , Yulianto S V , Atmaja A P
Published: March 2021

Development goals on this Panic Button application is to make it easier to call the nearest hospital for help. Panic Button works as a notification or alarm which tells that a danger is happening to an outpatient in emergency level and needs of immediate help. It is an android information-based which make it possible for outpatients to tell or send a notification message to the hospital medical workers when they are in an emergency problem. The system will send a notification after he/she clicks the SOS button. Using this emergency button is only to send a notification message and activate an integrated alarm. This system consists of mobile application, management information system and alarm system which was developed using Arduino Wemos D1 including ESP8266. Android application was developed using Google Firebase System as a notification system. When someone clicks the SOS button, the android application will send a data to management information system through Application Programming Interface (API). While the management information system will switch the alarm status to ‘danger’. The alarm system will check the alarm status frequently through API and if ‘danger’ status is found, it will change its status to ‘alarm’ and ring. All the hospital medical workers who are in charge of the patients who use this android application and is connected through the same system will get a notification message and they can check the source location or call the outpatients using smartphones.
AHP and TOPSIS Integration for Green Supplier Selection: A Case Study in Indonesia
Authors: Utama D M
Published: March 2021

Recently, the problem of global warming arising from manufacturing activities has attracted attention. One of the triggers of global warming is the aspect of production. This aspect requires raw materials supplied by the supplier. The selection of the right supplier by considering environmental aspects can reduce the problem of global warming. The purpose of this study is to integrate the AHP and TOPSIS methods in green supplier selection. Eight criteria are used to select suppliers weighted by the AHP method. AHP weighting results are used to select suppliers with the TOPSIS method. A case study was applied to an offset printing company in Indonesia. The results show that the quality criteria have the highest importance. In addition, the results showed that the AHP and TOPSIS methods were easy to use in Green Supplier Selection.
Face Recognition System using Micro Unmanned Aerial Vehicle
Authors: Atmaja A P , Setyawan S B , Setia L D , Yulianto S V , Winarno B , Lestariningsih T
Published: March 2021

With the price of UAV or people often call Drone getting cheaper, making this technology can be enjoyed not only for limited communities but also for the general public. The camera features mounted on the drone can be used for face detection and recognition. In this paper, we implement Haar-Cascade based classifier for face detection and recognition using OpenCV Python on a micro UAV that only 34.7 gr weight. The face detection process is done in real-time using an FPV camera that is controlled indoors at a distance of less than 50m. From the results of the experiment, it appears that the angle of the face is very influential, especially on the face that is not fully open, like a woman who wears a hijab. The best angle to take is in the position of flying in front of the face in accordance with the slope of the FPV camera mounted on the micro UAV.
Multi Criteria Analysis of Road Handling Type at Banda Aceh – Meulaboh National Road Segment Indonesia
Authors: Isya M. , Fadhly N. , Saputra Arie
Published: March 2021

The western and southern path of highway that connects Banda Aceh to Meulaboh City is national road. The distance between the two cities is 246 kilometers. On the connecting link between the two cities there are at least three locations in the mountainous area. Roads geometric in these locations have low capacity, uphill and downhill with high grade and also have a small curved radius. These conditions cause low levels of road services and the risk of traffic accidents is high. These three segment area are: Paro, Kulu and Geurutee mountain area. Traffic at these three road locations is often hampered and also has a high risk in terms of safety. Consider with current and future traffic condition, there is a discourse to increase the capacity of existing roads or plans for new road trace on the mountain with tunnels construction. In the feasibility study stage, there will generally be alternatives that must be selected for the best alternative. To choose the best alternative, it should be done by considering the many criteria. For this reason, this paper is the selection of the best route using the Multi Criteria Analysis (MCA) method.
Monitoring System of Heart Rate, Temperature and Infusion in Patients Based on Microcontroller (Arduino Uno)
Authors: Devis Yesica , Irawan Yuda , Junadhi  , Zoromi Fransiskus , Herianto  , Amartha Mohd Rinaldi
Published: March 2021

A patient who is hospitalized generally gets health monitoring including 3 parameters including heart rate, body temperature and level of intravenous fluid usage. These three parameters are used as an indication of the patient’s significant health development. Body temperature is needed because in addition to being an indicator of a person’s health, it also has little to do with heart performance, namely the more the body temperature moves away from normal body conditions, then it affects how fast or slow the heart pumps blood. throughout the body. To solve this problem, the researchers intend to create a three-parameter monitoring system, namely heart rate, body temperature and intravenous drips for patients. This monitoring system is also designed to provide a sound warning indicator in case of abnormal conditions in the monitored parameters. From the test results, it can be concluded that the device can display indicators of patient health development with 3 parameters, namely heart rate, body temperature and the level of infusion usage.
Synthesis of Sodium Silicate from Rice Husk Ash as an Activator to Produce Epoxy-Geopolymer Cement
Authors: Handayani L , Aprilia S , Abdullah  , Rahmawati C , Bakri A M Mustafa Al , Aziz I H , Azimi E A
Published: March 2021

Rice husk ash (RHA), a byproduct of the rice industry, is the primary source of amorphous silica for producing sodium silicate solutions to replace standard commercial sodium silicate in geopolymer mixture design. The effect of various concentrations of NaOH used as an activator to produce epoxy-geopolymer cement was studied. Three initial concentrations of NaOH were used (8, 10, and 12M) to examine the optimum dissolution and formation of silica oligomers that can function as the activator during the geopolymerization. The result indicated the increase of NaOH concentration raises the silica yield strength. The silica yield found was 65.84%, 70.53% and 72.06% on NaOH use of 8, 10, 12 M, respectively. IR-spectra results showed silica functional groups and the sodium silicate were successfully synthesized. The IR spectra indicated the appearance of hydroxyl bonds, which strengthen the geopolymer matrix. SEM results showed the C-S-H and N-A-S-H bonds in the geopolymer. With 10M NaOH, the compressive strength of the geopolymer cement paste was optimal at 27.53 MPa. Thus, Rice husk ash (RHA) is feasible to be used as an activator in high calcium fly ash-based epoxy geopolymer cement.
Design Indoor FM Communication Based on SDR and GNU Radio Using Validated Spectrum Analyzer
Authors: Harianto B B , Rifai M , Irfansyah A , Suprapto Y
Published: March 2021

The number of software in the telecommunications world allows us to make an FM simulation, one of the software is GNU Radio. This paper will explain FM communication simulations that use a guide between GNU Radio and RTL-SDR and are validated using a spectrum analyzer. The simulation is carried out twice, the first simulation tests the SDR transmit which will be tested in the simulation to be carried out in the GNU Radio worksheet. The second simulation tests an SDR receiver that uses a frequency of 100.3 MHz. Validation is done at a distance of ± 1 meter using a spectrum analyzer connected to the antenna and will receive frequencies of 60,65,70,75 and 80 MHz which will be compared with GNU Radio readings. The parameters to be used are signal to noise ratio (SNR) and beam power. From the results of the first simulation study using GNU Radio worksheets obtained the value of the emission power of -12.4 dBm and the second simulation obtained a value of -12.87. While the validation results show that the value obtained is the accuracy of 99.5% on the measurement of the transmitter’s power value while the signal to noise ratio of 99.78%.
The application of social attribute on Sustainable Affordable Housing (SAH): Klang Valley Area, Malaysia context
Authors: Alias N H , Basrah N , Majid R A , Rahim N A
Published: March 2021

Affordable housing has become government initiative in ensuring that all Malaysians are able to own their own homes. Hence, the availability of affordable houses in meeting the needs of the population is the main agenda in ensuring sustainability in affordable housing unit. In this regard, the social attributes representing one of the sustainable dimension are being investigated to see how far this housing development category is capable of meeting the needs of the local population. A total of 24 social attributes were reviewed on residential properties. The data were collected through a questionnaire survey distributed among 400 medium income earner respondents. Three of the respondent’s profile (job status, age and monthly income) were selected to be analyzed on the social aspects studied after presenting a strong significant relationship with affordable housing knowledge. Through the chi square test, the results show that 21 social attributes are very significant on affordable housing and should be fully applied in sustainable affordable housing development.
A Methodological Framework for Operationalization of Flood Risk Management
Authors: Herath HMM , Wijesekera NTS
Published: March 2021

Flood risk management has undergone significant transformations during the recent past. Climate change is very likely to bring a higher probability of extrememe weather events. Climate change is a significant challenge for urban growth in costal delta cities. Transformation of floodplains for urban development is a vital component of flood exposure, and changes in this component can lead to variations in flood risk. Socio ecological system conceptualizations suggests that resilience is the key to managing complex systems and to reduce vulnerability which is a result from the inherent uncertainty of flood risk. Theoretical understanding of flood risk management has advanced over the years but it is still seen that there are shortcomings in the operationalization concepts and methods. One of the main reason is lack of a common framework for clear recognition and understanding of the components of flood risk management for all stakeholders. Therefore, this research has questioned the current status of flood risk management and provide recommendations for operationalization. The Analytic Hierarchy Process (AHP) is a multi-criteria analysis technique that can be applied for structuring of complex decision-making problems involving multiple stakeholders, and scenarios. Therefore, this paper has developed a solution model for structuring the complexity of flood risk management and increase the certainty of the objectives of stakeholders. Result of the study has highlighted the main criteria and the sub criteria to structure the complexity of the planning process for operationalization of flood risk management.
Database and Application Migration in the Financial Services Industry Sector in the Acquisition Environment and Environmental Science
Authors: Trisnawaty N W , Hidayanto A N , Ruldeviyani Y
Published: March 2021

Financial Services Industry (FSI) is a sector with day-to-day business transaction operation dealing with numbers of classified information owned by its customers. It can be managed by the private sector or other institutions pointed by the government, either it is a bank or an insurance company. Aiming to improve services, acquisitions between companies can occur. There will be a migration of applications and databases in the acquisition process. This process will present certain constraints and challenges and prone to data fraud. Improper handling will also have a negative impact on the environment, especially e-waste generation of IT components from financial sector due to company’s acquisition case. So, study on database and application migration is important to be conducted. This research aims to identify constraints and challenge factors behind application and database migration in the FSI during a company acquisition. It uses a descriptive qualitative method with a case study approach that examines as much data as possible regarding the subject under study. The case studies use a single-case method, considering that the cases studied are unique and essential. The migration methodology used in this study combines application migration and databases from previous research journals and is added to the processes that occur in the field. Two factors become obstacles and challenges in the migration process, namely technology and non-technological factors. Database migration strategy uses a big-bang strategy based on joint decisions between the business and IT teams. The organizational challenge is the approval process for the transfer of membership management and data conditions that require validation and confirmation before migration. This research suggests using a mature migration strategy to anticipate technical and organizational constraints applying clear and scheduled policies and regulations.
Study of extra virgin olive oil as liquid insulation in transformer
Authors: Romadhona G , Wibowo K M , Royan R
Published: March 2021

Mineral oil, which is the basis of petroleum, has long been used as an insulating and cooling medium for transformers. In fact the petroleum has a limited supply, over time it will run out, cannot be renewed, even petroleum is poisonous, cannot be decomposed. In this study, researchers used vegetable oil that is renewable, biodegradable, and safe for living things and the environment, namely olive oil with good quality, from the first pressed of olives, which is called extra virgin olive oil to be applied to transformers as an insulating and cooling medium. To determine the feasibility of using extra virgin olive oil as transformer oil, the test is to determine the value of the breakdown voltage. Breakdown voltage is the voltage value when the transformer components become connected because oil cannot perform its function as insulation. Tests carried out according to international standards IEC 156, 296 and SPLN 49-1. The breakdown voltage value at room temperature (28 °C) is 46.73 kV, at a temperature of 50 °C where the transformer operates is 48.31 kV. At a temperature of 50 °C the breakdown voltage value is higher due to heating which causes water content, air bubbles, and voids to be reduced.
Mechanical properties of porous asphalt with gilsonite additive
Authors: Rochaeti R , Endawati J , Oktaviani T
Published: March 2021

The porous asphalt mixture is an asphalt mixture that consist of high void and a small proportion of fine aggregate. The presence of a high void reduces the value of marshall stability. Many attempts to increase the value of marshall stability by adding substances into the porous asphalt mixture has been done by several researchers. Modified porous asphalt can be achieved by adding gilsonite to the mixture which aims to accomplish the main function of the porous asphalt layer as well as to improve the quality of mixed performance. The method used in this study is an experimental method. The test that conducted in this study using two types of gradations that are Japan and Australia gradation. The research was Marshall characteristic test with 2.5%, 3.5%, 4.5%, 5.5%, 6.5% of gilsonite content and 0% as the control. The results showed that porous asphalt mixture using gilsonite proved to increase the value of Marshall stability compared to non-modified porous asphalt mixture by 24%. The mixture reaches a maximum state at 5.5% gilsonite content. The best performance is produced by the mixture using Japanese gradation.
Design and development of student attendance information system using QR code in accounting department of Politeknik Negeri Semarang
Authors: Sarana S , Sadida A , Mansyur A W , Suwondo A
Published: March 2021

This study aims to streamline the lecture attendance system and overcome indications of cheating on student absences in the lecture process in class. Manual attendance list causes lost time of lectures and waste of paper, and therefore the need for an attendance system to reduce these problems. Higher education with all its strategic activities cannot be separated from the importance of using information technology. One of the important activities routinely carried out by a tertiary institution is to record Academic Administration activities (teaching and learning process), this routine activity involves many interests both from the lecturers, administration and from the learning facilities and infrastructure they have. This activity must be made an information system in order to facilitate all parties and produce information that is fast and valid. One such information is student information about absence which can be caused by permission, illness or even negligence. This activity is carried out every day so that if and error occurs or negligence will harm all parties involved in the teaching and learning process therein. This article discusses how to design and build an Academic recording information system in the form of student attendance that can produce accurate and timely information available to meet the needs of students, Academic Administration and department managers so that the information system can be aligned with academic regulations and can be accepted by system users. The object used is the Semarang State Polytechnic Accounting Department. The method used is to use the Unified Model Language approach which consists of Use Case Diagrams, Class Diagrams, and Data Dictionaries. While the development model using waterfall, the stages include analysis of the existing system, concept design, physical design, implementation and testing. The output of the research is an Android-based student attendance information system application using QR Code which generates information for students, Academic Administration and department managers.
Sediments discharge analysis using tank model for disaster mitigation
Authors: Mulyono T , Jumi J , Azizah A
Published: March 2021

Environmental degradation as a result of deforestation carried out in the Catchment resulted in a decrease in its ability to store water. This has the effect of increasing the amount of sediment discharge. The process of estimating sediment discharges is very difficult because the data input variables are many and varied, usually, the data are very limited, because the erosion process occurs until the sediment discharge mechanism is quite complex. The process of sediment discharges in Catchment s is influenced by rain and surface runoff and is represented in the storage type. In this study, an approach using the Tank Model was conducted. The purpose of this study is to develop a tank model for sediment discharge analysis in disaster mitigation. The steps are setting the field experiment for collecting rain and discharge sediment data as the model input and setting the model analysis by making the structure and formulation of the tank model. There are 3 proposed tank models namely Tank Model 1 (three tanks, series, and cascade), Tank Model 2 (two cascade tanks), and Tank Model 3 (three cascade tanks). Model parameters are determined using the Genetic Algorithm (AG) method optimization approach. The analysis shows that Tank Model 3, composed of 3 (three) cascade tanks, represents a Catchment better than the other 2 tank models. This can be seen from the value of the accuracy of the model, namely the value of volume error (VE), the value of relative error (RE), the value of the mean least square error (RMSE), and the value of the correlation coefficient (R). But still has a range of differences for the value of sediment discharges, the cause may be a factor in the pattern of rain spread in the hydrological process, synchronization of the measurement process and data length, and the possible assumptions of the model parameters.
Euclidean distance digital image processing for jaundice detect
Authors: Rahayu E P , Widyawati M N , Suryono S
Published: March 2021

Jaundice is a serious health issue. Late treatment of jaundice cases in babies may result in neurodevelopmental disorder and irreversible brain damage. Diagnosis inaccuracy is usually caused by the fact that health professionals and health service providers often rely on visual observation instead of laboratory examination. Lack of expertise in detecting jaundice is a serious matter. This research proposes a method of web-based digital image processing as an alternative for early detection of jaundice based on babies’ complexion. Images of babies’ complexion and color calibration cards are taken to obtain images for online analysis. Determination of bilirubin levels is carried out using the method of Euclidean approximate distance of RGB values from babies’ complexion and those of color calibration cards. Results show correlation of Euclidean distance to bilirubin level of babies of 0.93596 and web-based digital image processing accuracy of 90%. These mean that the information system developed here is capable of detecting jaundice cases. This research was performed observationally in high-risk prenatal ward involving 30 infants as samples.
GPS-based fire detection system (Global Positioning System) and SMS Gateway
Authors: Aryanti A , Mekongga I , Dewi R S
Published: March 2021

This research aims to produce a GPS-based fire detection system (Global Positioning System) and SMS Gateway. The benefits of this detection system can detect early fire occurrence based on the detection of temperature conditions by accommodating the nature of the fire and able to detect any rise in temperature caused by the existence of the fire. This detection system must also be able to read any smoke produced by a fire. To realize the system, required sensors capable of reading the temperature and smoke. The Arduino Uno microcontroller is the brain control system of the system. At a temperature of> 35 C, the system will activate the DHT 11 and MQ 2 sensors that detect smoke> 50 ppm from fire. The system will activate Buzzer as a warning in the form of the next alarm sound Global Positioning System (GPS) will provide information in the form of coordinates of the location of the point of fire through GSM SIM900 Module Short Message Service (SMS) to the user. The results obtained mq2 = 128 ppm and temperature value = 38 ° C and GPS data with latitude of -3.04798388 and a longitude of 104.78263092. From the data it is seen that the mq2 value reaches> 50ppm and the temperature value reaches> 35 ° C, and the detector outputs buzzer sound and warning notification of coordinate point in the form of SMS containing the message “FIRE available” with the coordinates of the location of the fire detected by GPS.
Concrete mix design modelling based on variation of hidden layer and neuron of ANN for virtual learning development
Authors: Santosa S , Suroso S , Utomo M B , Martono M , Mawardi M , Santosa Y P
Published: March 2021

Artificial Neural Network (ANN) is a Machine Learning (ML) algorithm which learn by itself and organize its thinking to solve problems. Although the learning process involves many hidden layers (Deep Learning) this algorithm still has weaknesses when faced with a high noise data. Concrete mixture design data has a high enough noise caused by many unidentified / unmeasurable aspects. Information needs about the compressive strength of early age concrete (under 28 days) are often needed while the construction process is still ongoing. H2O’s Deep Learning type of ANN has been tried to predict the compressive strength of early age concrete, but the results are less than optimal. This study aims to improve the H2O’s-ANN prediction model using Bagging to reduce the influence of noise and overfitting. The lowest RMSE that are able to be achieved in this research with Bagging is 6.385 while it is 6,674 without Bagging. This result proves that Bagging is significant to reduce the Deep Learning error rate for predicting the compressive strength of early age concrete. Future work this model, as a new innovation in machine learning in civil engineering vocational education subject, can be used to various concrete mixture design and learning about concrete. Because this concrete mix design model is digital, it can be used for virtual learning. Currently the author is conducting research to create a virtual concrete mix design learning model.
Smart wind turbine three-layers flat blade with control system Arduino-based for blade angle
Authors: Sahid S , Suwarti S , Prasetyo B , Mulyono M
Published: March 2021

The objective of the design of a three-layers flat blade smart wind turbine with an Arduino blade angle configuration system is to study experimentally the performance of a wind turbine Three-layersflat blade horizontal guide with various wind speed variations, and apply automatically to blade blade speed average for weather. Tests are carried out to obtain the value of wind turbine power coefficient (Cp). Tests that use variations in wind and blade angle. Variations in wind speed are obtained by variations in refineries from wind turbines. The performance of Three-layersbflat blade wind turbines has the highest Power Coefficiency (Cp) values at certain blade angles on variations in wind speed at a wind speed of 5 m/sec with a blade angle of 15º at 57.84%; at a wind speed of 6 m/sec with a blade angle of 20º of 36.24%; at a wind speed of 7 m/sec with a 25º blade angle of 51.39%; at a wind speed of 8 m / sec with a blade angle of 30º of 39.37%; and at a wind speed of 9 m/s with a blade angle of 35º of 28.24%. After obtaining data about wind speed and angle with the highest Cp value, the wind speed that will be used as the input of the Arduino control system, and the output is a large blade blade that changes to adjust the wind speed.
Wind energy conversion system with capacity of 450 W in order to support teaching and learning process in the laboratory
Authors: Herlambang Y D , Mulud T H , Bono B , Suwarti S , Suwoto G
Published: March 2021

This study examines a 5-blade Horizontal Axis Wind Turbine to obtain the best performance at different wind speeds. The dimensions of this wind turbine have a rotor diameter of 1200 mm, blade length of 600 mm, number of blades 3 pieces, and blade material made of fiberglass. The research method uses different wind speed test parameters. The speed test using a blower is 4 m / s, 5.1 m / s, 6.5 m / s, and 7.5 m/s with the load of the lamp is 10 W, 20 W, 30 W, 40 W, 50 W, and 60 W. Subsequently analyze the characteristics of the wind turbine. The results of testing the wind turbine at a speed of 4 m/s obtained a maximum efficiency of 36.4% at 496.3 rpm turbine rotation. Power generator 15.8 W at a voltage of 20V and current 0.79 A.
Assessment of site-specific features to the unit cost of micro hydro power plant
Authors: I A V Marfori III , Culaba A B , Ubando A
Published: March 2021

Micro hydro power is a renewable source of energy and is commonly utilized for remote communities for electricity generation. The sustainability of a micro hydro system can be evaluated based on initial capital cost and the overall power output. The ratio of the capital cost and the overall power output is the unit-cost. In this paper, site specific characteristics specifically canal length and penstock slope are analysed to determine its effect in the unit-cost for micro hydro power plants. Calculations were conducted to quantify the total head loss that results from varying canal length and penstock slope. Capital cost is then evaluated using a disaggregated method based on literature. The results show that the canal length and penstock slope will give a significant effect on the micro hydro unit cost. Aside from the common micro hydro parameters of head and flowrate, the site-specific characteristic can also influence the sustainability of the system. It is therefore necessary to include the site-specific characteristics in the assessment of micro hydro systems.
Contact stress analysis and optimization of spur gears
Authors: Loc N H , Anh L T
Published: March 2021

Gear drive is one of the most important components in mechanical power transmission systems. Gears in gearbox generally fail when the working contact stress exceeds the contact fatigue limit. In the scope of this paper, the researcher studies gear design methods based on ISO 6336 and draws a comparison with AGMA 9001. In addition, this paper also presents the optimal gear design results with 3D gear models designed in CAD software, then imported into CAE software for topology and shape optimization. More specifically, the amount of material that can be removed from the gear body without affecting the properties of the gear mesh is considered and calculated. Consequently, the aim of this research is to reduce the weight of the gears and choose the optimal parameters of gear pair by contact stress.
Design of the double pass solar collector for drying
Authors: Nguyen Duy Tue , Nhut Do Tri
Published: March 2021

Solar energy is the free and nearly endless source which can be applied in various fields. Viet Nam locates near the equation and has enormous solar radiation, so this is the good chance for us to harness it. Moreover, Viet Nam is also the agricultural country with the large number of export product. With the large advantage in having enormous solar radiation, we can save up the large amount of energy for drying and other applications. In this paper, the 2 double pass solar collectors which have fins and without fins for drying were designed and simulated by CFD Ansys in some different conditions. The result displays that with the same size, the outlet temperature of the solar collectors with fins is 2 times higher than the without fins one. This temperature can reach 94.6°C with solar radiation 1026.32W/m2, mass flow rate 0.12kg/s and can reach 68.63°C with the same radiation and mass flow rate 0.18kg/s, so it is eligible for agricultural drying.