bluuebunny/crossref_metadata_2025 huggingface dataset:
Production of biodiesel based on moringa seed oil at varied reaction times by using CaO catalyst from chicken eggshells
Authors: Ruslan  , Hardi J , Sosidi H , Ridhay A , Agus A Y
Published: February 2021

Moringa seed oil has many long-chain fatty acid contents that very potential transformed become fatty acid methyl ester or biodiesel. CaO material that was obtained from calcinating of chicken eggshells can be used as a heterogeneous catalyst at biodiesel production from Moringa seed oil. The purpose of this research was to determine the reaction time that produced biodiesel with the highest mass fraction of fatty acid methyl esters and also to determine the characteristics of biodiesel. Biodiesel was made through a transesterification reaction by using CaO catalyst at a mole ratio of oil: methanol of 1:6 for 1, 2, 3, and 4 hours. Transesterification reaction for 2 hours resulted in a methyl ester mass fraction of 82.69%. GC-MS analysis result has shown that methyl oleate had the highest concentration of 86.56% at a retention time of 37.62 minutes. The characteristics of biodiesel including the acid number of 0.09 mg KOH/g, saponification number of 356.4 mg KOH/g, iodine number of 0.635 g iod/100g, cloud point of 13°C, pour point of 20°C, and cetane number of 61.45.
Helmholtz coils model as pulsed electromagnetic field therapy devices for fracture healing using comsol multiphysics
Authors: Nismayanti A , Jannah H , Rugayya S , Maskur  , Adawiyah R
Published: February 2021

The World Health Organization in 2009 recorded that more than a million people died due to accidents, and about 2 million people had physical accidents, namely fractures. The main challenge for clinicians today is finding an effective and inexpensive method of fracture healing. In this case, a pulsed electromagnetic field (PEMF) can be used, which is a non-invasive technique that is inductive and generates a magnetic field due to changes in the electric field. So this research aims to create a simulation design of PEMF therapy device for fracture healing. The stages of this research method are to make Helmholtz coil modelling of PEMF therapy device using Comsol Multiphysics with variations in the number of turns, the distance between two coils, voltage or current, and coil diameter, to obtain the correct magnetic field value to accelerate fracture healing. The result of this research is the successful design of a PEMF device that produces a magnetic field value B is 1.5 mT on the number of turns N is 150, the distance between two coils r is 2.5 cm, the current value I is 0.5 A, and coil diameter D is 5 cm.
The effect of polymer concentration in chloroform on P3HT:PCBM nanoparticulate organic photovoltaic device performance
Authors: Ulum M S , Sesa E , Belcher W
Published: February 2021

Investigations about the effect of concentration of polymer (1:1 Poly (3-hexylthiophene) (P3HT):phenyl C61 butyric acid methyl ester (PCBM)) in chloroform have been performed. Six different concentrations varying from 36 mg/ml to 179 mg/ml, were used to prepare P3HT:PCBM nanoparticulate organic photovoltaic (NP-OPV) devices. Using Dynamic Light Scattering (DLS), KLA-Tencor Alpha Step 500 profilometer, UV-visible spectroscopy (UV-Vis), we analyze and optimize the concentration of polymer in chloroform in producing NP-OPV devices. Higher concentration resulting in a bigger size of nanoparticle and thicker thin film we have, so that affects the efficiency of NP-OPV devices. In this investigation, the highest efficiency was achieved when using a concentration of 54 mg/ml.
Identification and characterization of ketapang seeds oil (Terminalia catappa L.) using the gas chromatography-mass spectrometry (GC-MS)
Authors: Napitupulu M , Firdaus Muhammad , Walanda D K
Published: February 2021

Ketapang plants (Terminalia catappa L.) grow on the beach and are known to contain oil. Research on oil content, lathering number, % FFA, and identification of fatty acids of ketapang fruit seed oil conducted using the Gas Chromatography-Mass Spectrometry (GC-MS) method. Results showed that ketapang seed oil content was 24.23%, saponin number was 33.3%, and % FFA was 3.65%. There are eight components identified in Ketapang fruit seeds. They are components of fatty acids: Hexadecanoic acid, octadecanoic acid, 9,12 hexadecanoic acid, 9,12 octadecanoic acid, 10-octadecanoic acid, 9-octadecanoic acid, docosanoic acid, and tetracosanoic acid identified.
Identification of distribution changes of leachate in a landfill
Authors: Musa M D T , Elisabeth J C , Jamidun  , Labania H M D
Published: February 2021

The distribution of leachate in the Kawatuna landfill, Palu City, which is still implementing the Open Damping system, has been researched in 2011 where it was detected up to a depth of 7 meters and led to reservoir of leachate. The Landfill Control system has been implemented, but the leachate pipe was not functioning, and part of the storage pool was damaged during the earthquake on September 28, 2018, so that leachate is scattered everywhere. This study aims to determine changes in the distribution of leachate used geoelectric-resistivity method with Wenner-Schlumberger configuration. Data were collected at 3 points within the landfill site and 1 point outside the location, with a length of 48 meters each and processed using EarthImager 2D software. From the research results, it is obtained that the resistivity value of leachate is 1–9.7 ohmmeter. Based on the cross-sectional resistivity analysis, leachate was spread to a depth of 9.7 m, which indicates an increase depth of 2.7 m and the distribution direction was not leading to reservoirs of leachate
Liquefaction and normal fault in Talise Valangguni and Tanamodindi Villages of Palu City; a preliminary observation of impact MW 7.5 earthquake in 2018 at Central Sulawesi Province, Indonesia
Authors: Abdullah  , Abdullah A I
Published: February 2021

Talise Valangguni and Tanamodindi Village are among the areas that affected by 28 September 2018 earthquake. This fact-based on our findings about ground surface deformation, the liquefaction and normal fault surface rupture effect. We then make further observations to record the existing hazard characteristics and delineate the affected area to see the hazards configuration to geological factors. The results showed there were 5 liquefaction areas with about 0.13-1.29 km2. The liquefaction effect characteristics that we found are fracture, downlift-uplift, wavy surface, sudden stagnant water, and lateral spreading. Liquefaction sites in this area are identical in seasonal river routes and strongly influenced by lithological, hydrogeological, and earthquake. The sediment deposits are dominated by saturated sand, which can experience significant infiltration, worsening the soil strength size. As a result, this area is susceptible to liquefaction effects when strong earthquakes occur. Meanwhile, normal faults are ± 1.5 km long, oriented west-east, where the southern block has decreased between 5-30 cm. We suspect that this fault existed before the earthquake and appear on the surface after the quake, contributed by shocks and gravity. We hope that this information can be used as a reference for spatial planning for Palu City in disaster mitigation.
Indication of ore mineralization in Bora Area, Sigi Regency, Central Sulawesi
Authors: Marliani  , Asrafil
Published: February 2021

Bora area have a mineralization system associated with geothermal activity, characterized by the presence of veins in the rock. This study aims to determine the indication of ore mineral. The method that used in this research is geological field survey and mineragraphic analysis. The results showed that the vein texture in the study area was in the form of crustiform-colloform, moss, and zoned crystal textures. Mineragraphic analysis results show the mineral content of ore associated with veins in the rock including pyrite, chalcopyrite and covelite. This proves that indication ore mineral in bora area is associated with the veins formed in the rock.
Rotation of the curve as far as α with center P(m, n)
Authors: Hasanah S U , Rahmawati S , Pathuddin
Published: February 2021

Mathematics consists of several scientific groups, including the geometry group. Rotation material is one of the sciences that is included in the transformation geometry group and is a deductive science and is still growing and developing, both in terms of theory and in terms of usage. In line with the development of transformation geometry, there have been many ways or approaches that have been successfully compiled by experts. The problems studied in this research are: How is the image of a curve when it is rotated as far as αº with the center P(m, n) and what are the characteristics of the image. This research uses literature review method, which is to conclude and identify theories that can support this research, especially those related to parameter equations, rotation and others. Using the parameter equation, image the curve with the equation f (x,y) = 0 to be rotated as far as αº with the center of P(m, n) is f (x,y) = 0. The relationship between the line and the equation f (x,y) = 0 with its image, if it is rotated as far as with the center of P(m, n), among others: If a straight line is rotated by the center of P(m, n), then its shadow coincides with the original line.
Characteristics of lipid content from the analysis of structural and optical properties of brown seaweed (Sargassum
polycystum) after defatting by petroleum ether: preliminary studies
Authors: Rahmi M H , Metusalach M , Rahim S W , Heryanto  , Tahir D
Published: February 2021

In Indonesia, one species of brown seaweed is Sargassum polycystum, which has not been optimally utilized. Whereas their wide range of potentiality, especially their bioactive compounds. Several authors have reported that the chemical composition of seaweeds varies according to maturity, habitats, environmental conditions, treatment, and species. This work describes the structural and optical properties of Sargassum polycystum after treatment by petroleum ether to remove lipid content. The structural properties determined from the quantitative analysis of XRD spectra. The chemical bond and optical properties determined from the quantitative analysis of FTIR Spectra by applying Kramers-Kronig relation. The data XRD showed an increasing the average of the crystallite size from (23.92 nm Scherrer method; 14.35 nm Williamson-Hall method; 19.23 nm Size strain plot method) to (32.39 nm Scherrer method; 20.07 nm Williamson-Hall method; 28.06 nm method) after treatment. The analysis of FTIR showed COC, CCH, CH, and OH bonding.
The thinking process of the teachers with pseudo contingent when giving scaffolding in the teaching and learning of mathematics
Authors: Anwar  , Yani B , Khairunnisak C , Mailizar
Published: February 2021

This study aims to describe thinking processes of teachers with pseudo contingent when they give scaffolding in the teaching and learning of mathematics. The participants of this study were two teachers who teach mathematics at high schools in Banda Aceh and Aceh Besar. To collect the data, the researchers recorded the teachers’ classroom practices by using videotape. Later on, the researchers interviewed the teachers by using a method namely stimulated recall. Furthermore, the researchers explored the teachers’ thinking processes based on three criteria consisted of generating ideas, clarifying ideas and assessing ideas. Findings showed that the participants only considered learning outcome as a component which has to be mastered by the students rapidly. In other words, the teachers only assisted the students to understand the subject without considering the value of their assistance. Moreover, the participants were not eager to understand the mathematical concepts. Therefore, they had misconceptions about contents of mathematics given and were not able make decisions when they gave the scaffolding to the students.
High school students’ mathematic literacy performance in solving linear programming problem
Authors: Sugiarto Iwan Jadi , Usodo B , Saputro D R S
Published: February 2021

The mathematic literacy performance is the capability that is gotten by students applied on daily activities. The ability which uses logical thinking and knowledge that they got can solve the proses of learning till the subject can be used for life in 21 centuries. This research supposes to describe mathematic ability of student on grade XI IPA 1 SMA N 1 Karangdowo. This type of research is qualitatively descriptive. The research subject of 32 students which are taken using purposive sampling method. The result of research shows that mathematic literacy performance of student only reach on the third level, those are can present the resource information. The first indicator is 87,50% which the highest categorized. The second indicator is 75,78% which the higher categorized. The third indicator is 70,31% which the medium categorized. The fourth indicator is 39,06% which the low categorized. The fifth indicator is 1,56% which the lower categorized and on the sixth indicator is 0%, so that overall can be seen the average mathematic literacy performance for student grade XI IPA 1 is 45,70% with low categorized. The teacher should not push comprehension routine procedural but also variety in giving problem.
Exploration Ethnomathematics on Traditional House Ume Kbubu in North Central Timor Districts
Authors: Tlonaen Maritce Alfrida , Deda Yohanis Ndapa
Published: February 2021

One solution to preserve the culture that exists in each region is to introduce culture to students through the world of education especially mathematics education. It is said so because mathematics has actually been applied by the community in various daily activities. Introducing culture through mathematics learning can be done by observing regional culture, exploring the mathematical concepts contained in the culture and then applying it in class learning. The purpose of this study is to explore the hidden mathematical concepts in the traditional house of Ume Kbubu in North central Timor (TTU) Districts. This research is a qualitative research with ethnographic approach. Data collection techniques through interviews, observation, and documentation. Data analysis techniques were carried out by data reduction, data presentation and conclusion drawing. The results of this study were mathematical concepts contained in the structure of Ume Kbubu buildings in TTU Regency including cones, tubes, circles, squares and similar concepts. From these results it can also be explained to students about points, lines and angles. Through mathematical concepts wich found it can be used to facilitate students to understand the abstract mathematical concepts. In addition, it can also be used as a tool to introduce students to the existing culture.
How are Students’ Conceptual Understanding for Solving Mathematical Problem?
Authors: Kholid Muhammad Noor , Imawati Ayu , Swastika Annisa , Maharani Swasti , Pradana Lingga Nico
Published: February 2021

This study describes students’ conceptual understanding in solving mathematical problems. Conceptual understanding is an important component in learning mathematics. By learning mathematics students are able to apply concepts and think logically. The qualitative research took students of SMP Negeri 1 Gatak Sukoharjo Indonesia. There were 59 students who were tested to find out the conceptual understanding. All students are categorized into 16 students with high mathematical ability (Subject S-1), 25 students with moderate ability (Subject S-2), and 18 students with low mathematical ability (Subject S-3). Data collected through tests, video recordings, field notes, and interviews. Data analysis techniques include data reduction, data presentation, and drawing conclusions. The validity of the data is obtained through validation and triangulation. Subjects with high mathematical ability can solve mathematical problems correctly. Subjects with moderate mathematical abilities are able to solve the given problem but not all indicators on understanding the concept fulfilled. Subjects with low mathematical abilities are not able to solve problems precisely. Research contributes as a new reference to the theory of conceptual understanding.
The effect of using worksheet on students’ number sense ability
Authors: Wulandari Nourma Pramestie , Safitri A S , Novitasari D , Salsabila N H , Suliani M
Published: February 2021

Number Senseis a basic thing to learn mathematics, especially on numbers material. As a matter of fact, the preliminary research showed that students’number senseability was so poor. Therefore, using students’ worksheet as learning media on numbers material are expected to help students to understand the material. It implies, students’number senseability can be better. The aim of this study is to figure out the effect of using worksheet on students’number senseability. This study is using quantitative method with Wilcoxon Test. The number of 37 students were involved as a sample and chosen by random sampling technique. The result showed that the average score = 75.24 after students got the worksheet are higher than before they got the worksheet = 55.04. The result of hypothesis withZscore = -5.314 and p value = 0.000, soHtwas accepted. It means that there was different between before and after using the students’ worksheet. This result also showed that there was the effect of using worksheet on students’number senseability with an average increase of 19,00.
Learning Style Preferences and Students’ Abilityn Mathematical Investigation on Display Data
Authors: Maulina Shofiya , Nisa Lulu Choirun , Nadhifah
Published: February 2021

A mathematical investigation is an inquiry activity to solve a mathematical problem. Good investigative skills will support mathematical problem-solving and mathematical literacy. The purpose of this study is to explore students’ mathematical investigation based on Kolb’s learning styles: diverging, assimilating, converging, and accommodating. Mathematical investigation is measured by four indicators, i.e Specialization, Conjecturing, Justification, and Generalization. This is a qualitative study and the subjects were 7th-grade students of Islamic Secondary School Manahijul Huda Ngagel, Pati, Central Java. The results showed that there are differences students’ ability of mathematical investigastion for accomodator and divergent, also for accomodator and convergent. Students with accommodating learning styles have better investigative abilities, demonstrated on indicators specialization, conjecturing, justification and generalization. Students with assimilation learning styles have a good specialization and generalization but are less successful in the process of conjecture and justification. Conversely, students with convergent learning styles are only good at specialization, but not for conjecturing, justification, and generalization. Students with divergent learning styles have the most difficulty when doing divergent less able to do specialization, conjecture, and generalization.
Visual-spatial intelligence level of junior high school students: what difficulties are experienced by the students
Authors: Triutami Tabita Wahyu , Novitasari D , Tyaningsih R Y , Elvierayani R R , Lu’luilmaknun U
Published: February 2021

Visual-spatial intelligence is one important intelligence to solve mathematics problems, especially in geometry. The present research aims to find out junior high school students’ visual-spatial intelligence level and to identify the components of visual-spatial intelligence that are poorly mastered by students. The instrument of this research was a visual-spatial intelligence test. The test consisted of 18 multiple choice questions arranged based on three components of visual-spatial intelligence. The participants were 77 third grade junior high school students in Lombok, Indonesia. The collected data were analysed a using descriptive quantitative method. The findings were 2 students had a high level of visual-spatial intelligence, 65 students had an average level of visual-spatial intelligence, and 10 students had a low level of visual-spatial intelligence. In terms of the ability to accurately perceive the visual world, students were still weak when it comes to counting a particular configuration question. In terms of transforming visual experience, students have difficulty when working on questions about mental rotation. In terms of modifying visual experience, questions about folding and unfolding a particular configuration were poorly mastered by students.
The effect of application of contextual teaching and learning model on mathematical problem solving ability based on self regulated learning of high school students in Pekanbaru
Authors: Zubaidah Amir MZ , Supriyanto Desi Puspitasari , Andriani Lies , Nurdin Erdawati
Published: February 2021

This objective of study was to analyze whether any differences in mathematical problem solving abilities (KPMM) between the students taking Contextual Teaching and Learning (CTL) with students taking Direct Learning (PL), based on students’ Self Regulated Learning (SRL), and finding whether there were any effects of the interaction between the learning model and SRL on KPMM students. This research was a quasi-experimental study involving social science class X students in the odd semester at SMA Negeri 2 Pekanbaru in the academic year 2019/2020. The sample taken was class X IPS 1 and X IPS 2 using purposive sampling. Research data were collected through posttest of mathematical problem solving abilities, students’ SRL questionnaire. Data were analyzed through two-way ANOVA. Based on the findings of data analysis, it were concluded that: 1) There were differences in KPMM between students taking CTL learning with students taking PL; 2) There were differences in KPMM students when analized from the level of SRL; and 3) There was no effect of interaction between learning models with SRL on KPMM students
The decision tree classification with C4.5 and C5.0 algorithm based on R to detect case fatality rate of dengue hemorrhagic fever in Indonesia
Authors: Abdullah Afif Zakiy , Winarno B , Saputro D R S
Published: February 2021

Dengue hemorrhagic fever (DHF) is a deadly disease that is transmitted through mosquito bites from the genus Aedes especially Aedes aegypti, Aedes aegypti can occur every year and affect any age. DHF has a high case fatality rate (CFR). Therefore we need a method that can detect CFR of DHF in Indonesia, one of which is the decision tree classification based on C4.5 and C5.0 algorithm. C4.5 and C5.0 algorithm starting with forming a root node and ending with a leaf node by evaluating attributes using information gain to measure the effect of attributes in classifying a dataset. In this article, an applied research is carried out, namely applying the decision tree classification with C5.0 and C4.5 algorithm based on R software to detect CFR of DHF in Indonesia. The attributes used are the incidence rate (IR), population density, many hospitals, and many medical personnel. The results show that C5.0 algorithm has a big error than the C4.5 algorithm, while the C5.0 algorithm has a smaller tree than the C4.5 algorithm.
A Class of Non-Linear AGARCH(1,1) Model in Modeling Volatility of Returns
Authors: Nugroho Didit Budi
Published: February 2021

There are various forms of GARCH (Generalized Autoregressive Conditional Heteroskedasticity) modeling. The contribution of this study is to propose a class of non-linear AGARCH (Asymmetric GARCH) model by applying the Simple Tukey transformation to the lagged-volatility equation. The model is fitted to the daily returns of buying exchange rate of the USD (US Dollar) to the IDR (Indonesian Rupiah) from January 2010 to December 2017. The Adaptive Random Walk Metropolis (ARWM) method is employed in the Markov chain Monte Carlo algorithm to estimate model parameters. This study finds that both asymmetric effect (between return and volatility) and non-linearity in volatility are statistically significant, suggesting to incorporate both parameters into the GARCH(1,1) model. To choose the better fit model, the Log-likelihood Ratio Test (LRT) and Deviance Information Criterion (DIC) are employed. The empirical results indicate that the proposed model outperforms the basic AGARCH(1,1) model. Therefore, this study suggest a new class of non-linear AGARCH model.
AMAZonn (A Multicollinearity-adjusted Adaptive LASSO for Zero-infated Count Regression) with Weight of Expectation Maximization Standard Error Adaptive LASSO (SEAL AL) for Zero Inflated Poisson Data
Authors: Ismah  , Notodiputro Khairil Anwar , Sartono Bagus
Published: February 2021

Lasso as selecting predictor variables continue to experience development like an adaptive Lasso which gives weight value in its formula. In a modelling case, variables selecting technique is needed in order to get a stable model, however, multicollinear cases are often found in several cases which caused the models obtained are unstable since the values of variance became large. Besides, data counting on response variable, with the presence of excess zero, causes the linear model cannot be applied, hence, using generalized linier modelling with zero inflated poisson (ZIP) model can become the solution. Thus, in this research, ZIP model will be applied after selecting the variables through AMAZoon (A Multicollinearity-adjusted Adaptive LASSO for Zero-infated Count Regression) with Weight ofExpectation Maximization Standard Error Adaptive LASSO(SEAL AL), and the comparison towards the results gained by ZIP model without prior variables selection will be done. The comparison was seen based on the value of the smallestAkaike Information Criterion(AIC). The data analysis revealed that there was multicollinear case in the data, and also ZIP model, after conducting the variables selection by using AMAZoon with Weigth SEAL AL, reached smaller AIC than ZIP model which having no variable selection. Therefore, ZIP model after the selection of variables by using AMAZoon with Weight of SEAL AL was better to be used when multicollinear happened.
Microstructure and nanomechanical properties of the exoskeleton of an ironclad beetle (Zopherus haldemani)
Authors: Lee Nayeon , Berthelson Parker R , Nguyen Vina , Garrett Me'Lanae , Brinda AnneMarie K , Moser Robert D , Horstemeyer M F , Rhee Hongjoo , Prabhu R K
Published: February 2021

This study examined natural composite structures within the remarkably strong exoskeleton of the southwestern ironclad beetle (Z. haldemani). Structural and nanomechanical analyses revealed that the exoskeleton’s extraordinary resistance to external forces is provided by its exceptional thickness and multi-layered structure, in which each layer performed a distinct function. In detail, the epicuticle, the outmost layer, comprised 3%–5% of the overall thickness with reduced Young’s moduli of 2.2–3.2 GPa, in which polygonal-shaped walls (2–3 μm in diameter) were observed on the surface. The next layer, the exocuticle, consisted of 17%–20% of the total thickness and exhibited the greatest Young’s moduli (∼15 GPa) and hardness (∼800 MPa) values. As such, this layer provided the bulk of the mechanical strength for the exoskeleton. While the endocuticle spanned 70%–75% of the total thickness, it contained lower moduli (∼8–10 GPa) and hardness (∼400 MPa) values than the exocuticle. Instead, this layer may provide flexibility through its specifically organized chitin fiber layers, known as Bouligand structures. Nanoindentation testing further reiterated that the various fibrous layer orientations resulted in different elastic moduli throughout the endocuticle’s cross-section. Additionally, this exoskeleton prevented delamination within the composite materials by overlapping approximately 5%–19% of each fibrous stack with neighboring layers. Finally, the innermost layer, the epidermis contributing 5%–7 % of the total thickness, contains attachment sites for muscle and soft tissue that connect the exoskeleton to the beetle. As such, it is the softest region with reduced Young’s modulus of ∼2–3 GPa and hardness values of ∼290 MPa. These findings can be applied to the development of innovative, fiber-reinforced composite materials.
Application of spectra pre-treatments on firmness assessment of intact sapodilla using vis-nir spectroscopy
Authors: Kusumiyati  , Mubarok S , Sutari W , Hadiwijaya Y
Published: February 2021

This study aimed to obtain the best calibration model from various spectra pre-treatment methods to assess sapodilla fruit firmness using vis-nir spectroscopy. Before the spectra data measurement, samples were treated with storage of 0, 5 and 10 days at room temperature. Spectra data measurement was carried out using the NirVana AG410 visible and near infrared spectrometer from 312 to 1050 nm with interval of 3 nm. RAW spectra were pre-treated using the multiplicative scatter correction (MSC), standard normal variate (SNV), and Savitzky-Golay first derivative (dg1) with 9 points of smoothing. The calibration model was developed using PLS (partial least squares) method. Validation was done by K fold cross validation method. The results showed the MSC and SNV spectra were able to eliminate noises of RAW spectra, whereas in the dg1 spectra, noises were still visible. The best model was acquired by SNV spectra with R2 (coefficient of determination) of calibration and validation of 0.882 and 0.870, root mean square error of calibration (RMSEC) and root mean square error of cross validation (RMSECV) values of 2.92 and 3.08, and the ratio of performance to deviation (RPD) of 2.76. The result indicated the spectra pre-treatments were able to improve the accuracy of calibration model on assessment of sapodilla fruit firmness.
Rapid detection of patchouli oil mixed by coconut oil using NIRS technology and chemometrics method
Authors: Zulfahrizal  , Muhammad Syaifullah , Munawar Agus Arip , Mahlinda
Published: February 2021

Aceh patchouli oil is sometimes mixed with various oils for profit resulting in the low quality of patchouli oil. This low quality caused Aceh patchouli oil to depress its selling price. The main objective of this study is to develop NIRS technology to investigate the authenticity of patchouli oil mixed with coconut oil using Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) methods. This present study uses 6 kinds of sample treatment namely pure oil and mixed oil with a total of 42 samples for calibration and 18 samples for validation. The results showed that NIRS Technology with PCA and LDA methods provides a solution opportunity to solve the problem of counterfeiting patchouli oil with coconut oil. The PCA method successfully obtained a classification model that was able to provide a clear visual appearance to distinguish between pure patchouli oil and a mixture of patchouli oil and coconut oil. Meanwhile, the LDA method successfully obtained a validated classification model with the number of errors 1 out of 18 independent validation samples to distinguish between pure patchouli oil and non-patchouli oil.
The KUB chicken farming technologies for the household in West Nusa Tenggara
Authors: Astiti LGS , Widiastuti E , Sudarmayanti BA , Adnyana IPCP , Yasin M , Triguna Y , Agustini N
Published: February 2021

In Indonesia, there are various serious efforts have been conducted by the government to fight against the poverty until recently. One of the leading projects recommended by the Indonesian Agricultural Development Research Agency was the assisted KUB chicken farming packages that has been carried out through the 2018-2019 BEKERJA Program. The KUB chicken was recommended because it has various advantages such as being able to be harvested at the age of 70 days and high egg production (180 eggs/year). Meanwhile, to assess the effectiveness of the program, especially in behavior and perceptions of poor households (participant of the program) involved towards farming of KUB chicken, an in-depth study was conducted in two sub-districts in Central Lombok district. There are 200 respondents randomly selected from 20 villages. The required data was gathered with structured questionnaire. It uses 13 indicators of KUB chicken farming technology as an instrument. Furthermore, the data, then analyzed using of descriptive analysis, regression and t-test with SPSS software. The result shows that gender, age, education and experience of respondents did not have a significant effect (P> 0.05) on their perception about KUB chicken farming technology. In contrary, the knowledge that taught through technical assistance has significant impact (P<0.05) on it. Amongst 13 components of technology that has disseminated and known by respondents, 38% of it has been applied. Moreover, the total score of respondent’s perception on farming of KUB chicken was 3.57. It means that the poor household involved in the program has accepted the technology for farming of KUB chicken that has been disseminated.
Rapid classification based on image using residual neural networks
Authors: Setiawan H , Millinath R
Published: February 2021

Every human being is created with a certain gender, female or male. Gender differences provide opportunities for mating and producing offspring for regeneration. With the development of the world of information technology, the recognition of gender based on digital photos can be done for the needs of biodata, permission to access public toilets and others. The process of sex classification based on photographs with the use of residual neural networks has been carried out in this study. The process consists of several stages, namely the learning process of the features of each image that has been classified in a male or female class. The next process was carried out by resnet classification of 3,354 pictures (jpg) of men (1414 files) and women (1940 files). The data divided into 2 parts, 80% for training, 20% for testing data. The results of total images of 588 from total available data obtained an accuracy rate of 89.49%.
The investigation on cowrie honeypot logs in establishing rule signature snort
Authors: Satria E , Huda T P S , Iqbal M , Sarjana F W
Published: February 2021

The attack of brute force is still one of the popular attacks used to hack into your account unauthorized by a computer system. Brute force is also the most crucial attack and has a high risk of the system being taken over. Investigating brute force attacks is useful for building strong computer network defense systems. In this study, Snort acts as an intrusion prevention system and Cowrie Honeypot as a tool to investigate anomalous behavior that occurs when a brute force attack happened. The aim of this research is to improve Snort's rule signature performance from brute force attacks by relying on the results of the Cowrie Honeypot log investigation. The results obtained, namely Snort rule signature successfully improved detection capabilities with performance in matching the same packet only requires a short processing time, respectively: 3.5 microsecs in Hydra attacks, 3.8 microsecs in Medusa attacks and 2.3 microsecs in Ncrack attacks.
Agriculture environment monitoring: rapid soil fertility evaluation by means of near infrared spectroscopy
Authors: Munawar A A , Yunus Y , Devianti D , Satriyo P
Published: February 2021

In agricultural practices, the development of environmental controlling programs is essential in maintaining soil fertility. It should be monitored constantly in real time situation by predicting soil properties such as nutrients and mineral contents. The main purpose of this presented paper is employ the near infrared spectroscopy (NIRS) technique in determining nitrogen (N) and magnesium (Mg) content of agricultural soil rapidly and simultaneously. Near infrared spectra data of soil samples were obtained by acquiring absorbance data in wavelength range from 1000 to 2500 nm using a portable sensing device NIR with a photodiode array detector. Spectra data were enhanced using mean normalization approach to improve prediction accuracy. Further, prediction models were developed by means of partial least square regression (PLSR) followed by cross validation. The results showed that both soil fertility properties (N and Mg) can be predicted by NIRS with maximum correlation coefficient (r) were 0.93 and 0.91 for N and Mg respectively. It may conclude that NIRS technique was able to be used in agriculture environment monitoring especialy to predict soil fertility properties.
Thermal vision of oil palm fruits under difference ripeness quality
Authors: Fauziah WK , Makky M , Santosa  , Cherie D
Published: February 2021

Indonesia is the primary producer of palm oil. The edible oil in the palm fruits mesocarp obtained through mechanical extraction, where the quantity and quality of oil regulated by the fruit ripeness upon harvest. When oil forms and accumulate in the mesocarp, it replaces the moisture until the optimum ripeness reached before oil started to deteriorate. However, due to its nature, harvesting the fruits at optimum ripeness is challenging. Since water and oil have different thermal properties, in this study, we developed a Thermal-Vision system to observe the thermal properties of the fruits before harvest. Five harvest windows selected, namely 110-130, 131-150, 151-170, 171-190, and 191-200 days after anthesis (DAA). The recorded images then processed to determine the surface temperature of each fruit. The oil obtained from fruits as quality parameter evaluated. Additionally, Moisture Content (MC) of fruits mesocarp measured. Models were developed using the Multilayer Perceptron Artificial Neural Network algorithm to correlate fruits' thermal properties with measured parameters (Oil Content). The coefficient determination (R2) of FFB ripeness with the OC of 0.9058 and OC with temperature of 0.8039.The models successfully predict with R2 upon calibration was 0.7818 with SEC of 0.0831. While upon validation R2 value was 0.9535 and SEP of 0.0003.
Development of a low-cost modular VIS/NIR spectroscopy for predicting soluble solid content of banana
Authors: Pahlawan M F R , Wati R K , Masithoh R E
Published: February 2021

Soluble solids content (SSC) is one of the most important parameters of banana associated with taste and consumer acceptance. NIR spectroscopy has been applied for nondestructive determination of SSC, but limited studies were conducted for a low-cost and modular VIS/NIR spectroscopy. This study was conducted to develop a calibration model to predict SSC in bananas using a modular type of VIS/NIR spectroscopy in the range of 350-1000 nm by varying distances of fiber optic probe to samples. Two varieties of bananas, namely Musa acuminata × balbisiana and Musa acuminata ‘Lady Finger’ were used. Partial least square regression (PLSR) was used to build a calibration model and to predict SSC of bananas. Normalization, baseline correction, standard normal variate (SNV), and multiple scattered (MSC) correlation were used for spectra preprocessing. The research showed that using 2 cm probe-sample distance and SNV method resulted in the best model with the coefficient correlation of calibration

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and prediction

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of 0.95 and 0.87, respectively. This study proved that probe-sample distances affected the efficiency of the model for VIS/NIR spectroscopy. This work concluded that the low-cost modular VIS/NIR spectroscopy is a promising tool for SSC measurement.
Novel utilization of coffee processing by-products: kombucha cascara originated from ‘Gayo-Arabica’
Authors: Muzaifa M , Andini R , Sulaiman M I , Abubakar Y , Rahmi F , Nurzainura
Published: February 2021

One of the current significant environmental challenges that have to be dealt with the majority of farmer in Indonesia, especially those on Gayo highlands - is the absence of an optimal utilization of coffee by-products or waste, which is deliberately produced in a great amount during the coffee processing. The Gayo highlands are located in the middle regions of Aceh province and widely known as the most extensive arabica coffee plantation all over Indonesia, with a total area 101,473 hectares. The aim of this research was to optimally utilize the by-products or the exfoliated cherry-pulp into the so called kombucha cascara bearing great economical potential. However, further information in terms of its optimum processing condition (the length of fermentation duration, concentration of kombucha starter) from the cherry pulp into kombucha cascara has been much unexplored. In order to reveal that, we were trying to apply the effects of wo determinants, namely: i) fermentation duration (8,12 days); ii) starter concentration applied (3%, 5%, and 7%) on kombucha cascara’s chemical parameters [pH, total phenolic amount, antioxidant activity] and sensory in the form of hedonic test. Such test enabled us in describing consumers’ preference based on its ‘pronounced’ the taste. Results showed that pH was ranged from 2.63 until 3.10, meanwhile, a relatively high antioxidant activity ranging from 25.78 and 51.69% noted with a total phenolic compound between 64.00 - 105.20 mg GAE (Galic Acid Equivalent)/ml were measured. This can be inferred that quality was shown to be deliberately affected both by the length of fermentation and starter’s concentration, albeit the first one was to be more affecting. The longer the fermentation period, the lower the acidity value, and interestingly, significant decreases by total phenolic compound and antioxidant activity were also measured. It is also concluded that 12-days fermentation process added with 5% started received the highest score for sensory test.
Database application based on quick response method in Subulussalam Aceh
Authors: Putra D S , Fardiansyah  , Febrianti D H , GS A D
Published: February 2021

Customers are a very important part of the sustainability of a company. The PT. PLN (Persero) is a state electricity company in Indonesia. It has many customers in the Subulussalam district. This study aims to design a customer data management system for PT. PLN (Persero) using the QR code scanner. The method used in this system uses a use case diagram and waterfall model. The database design uses the Entity Relationship Diagram (ERD) model. The system implementation uses PHP as the system interface and MySQL as its database. By scanning the QR code on the customer's meter so the officer can find out the customer's identity number and data. The system test results show that field officers can access customer data in realtime so that the information obtained becomes faster and more accurate.
Chemical and microbiology assessment of salted fish (anchovy and catfish) product in Banda Aceh District as a parameter of food safety
Authors: Lubis Y M , Zaidiyah  , Yusriana  , Dinti S S
Published: February 2021

The process of salted fish which tends to neglect the elements of sanitation and hygiene and the use of formaldehyde provides a potential hazard if consumed by the community. This study aims to determine the chemical quality parameters of catfish and anchovy salted fish products circulating in Banda Aceh District Market. The analysis carried out are the analysis of moisture content, salt content, acid insoluble ash content, total plate count and formalin qualitative test. The results showed that 3 out of 5 local markets meet the SNI (Indonesian National Standard) requirements (8273: 2016) for moisture content. Salt content for both of salted fish in 5 local market meet the SNI. On the other hand, acid insoluble ash content and total plate count find higher than SNI requirement. The test results showed that catfish and anchovies in all the selected market are positive containing formaldehyde.
Study of mineral properties in granite rocks Ujung Karang village, South Aceh
Authors: Iman B B D , Sihombing A R , Jalil Z , Amri A , Putra D S
Published: February 2021

Granite rock is a non-metallic rock, one of which is located in Ujung Karang Village, South Aceh Regency, this rock has a high commercial value, but depends on the type and color that is owned. So to find out need to do a basic study of these rocks. The purpose of this study was to obtain preliminary information on the constituent minerals and dominant colors that appeared in the granite rocks of Ujung Karang Village. This research method uses X-ray fluorescence (XRF) and Scanning Electron Microscopy (SEM) techniques. The test results showed that 17 dominant mineral phases were identified, while others were minor phases. The largest mineral phase is in the SiO2 compound at 63.6%, while the smallest mineral phase is in the ZnO compound at 0.01%. While the surface morphological observations obtained 46.49wt% O elemental bases, then 28.60wt% Si elemental bases, and 09.57wt% basic element Al, besides these elements, there are also other elements namely 05.65wt% O basic elements, 04.68wt% Na basic elements %, the element Fe is as broad as 03.72wt%, and Mg is as basic as 01.71wt%. The surface morphology in these rock samples is irregular with varying grain sizes. Visually visible colors are dark and white, and it can be assumed that the elements contained in the granite are predominantly Si or Silica elements.
A Method of Reliability Weight Distribution of Wind Turbines
Authors: Li Xin , Wang Ying , Zhang Lele , Zhao Jingshen , Liang Sheng
Published: February 2021

Aiming at solving the reliability weight distribution problems of SL1500 wind turbines from Sinovel Wind Group Co., Ltd, an integrated method of historical fault maintenance data-based, improved fuzzy hierarchy analysis process and entropy weight method is proposed to achieve the weight distribution of each subsystem of wind turbine. The method takes both maintenance data and expert knowledge into consideration, which can well avoid one-sided problem from the view of considering only subjective or objective factors. The modified weight distribution algorithm is more practical for further reliability evaluation of wind turbine.
An Improved High-Moment Method for Reliability Analysis Based on Polynomial Chaos Expansion
Authors: Zhao Jianyu , Guo Jianbin , Wang Jingyan , Xu Hao
Published: February 2021

For structural reliability analysis, the moment method provides a relatively effective way to estimate the failure probability only using the moment information of a given model. However, it may introduce extra computation costs to obtain the required moments of the model output accurately, especially for some high moment methods like the third-moment method and the fourth-moment method. This study improves the traditional high-moment method based on the polynomial chaos expansion (PCE). The proposed method firstly derives the PCE-based high order moment algorithm by multiplying the orthogonal polynomials of PCE itself. Then, the integration between the PCE and the high-moment method are proposed for failure probability calculation. Besides, different input distributions as well as correlations among input variables are also taken into consideration to expand the scope of suitability. Compared with the existing methods, the proposed method is more efficient and accurate for structural reliability analysis by an engineering example.
Study on the Reduced Reliability of A Certain Amplifier Caused by Electrostatic Discharge (ESD)
Authors: Zhu Guixia , Lan Jian , Li Diliang , Qian Yugang , Zhou Tianmi , Hu Yuying
Published: February 2021

This paper introduces and analyzes the single-channel tripping accident of a reactor as a result of false triggering of a certain amplifier caused by electrostatic discharge (ESD). In response to this problem, a simulated operational amplifier circuit platform is built in practice to verify the analysis results, and a solution is proposed at last. In addition, further analysis is made to the existing preventive maintenance plans, and cable shielding is found to be problematic; therefore, the principle and analysis of cable shielding are given here.