bluuebunny/crossref_metadata_2025 huggingface dataset:
Photocatalytic sensor for chemical oxygen demand flow system using N-TiO2/Ti electrode: determination of glucose and potassium hydrogen phthalate
Authors: Nurdin M , Ritonga H , Astria M , Salim L O A , Annisa D , Maulidiyah M
Published: May 2021

The design of the Chemical Oxygen Demand (COD) flow system using TiO2/Ti and N-TiO2 /Ti electrodes has been carried out. TiO2/Ti electrodes were synthesized from the anodizing process followed by the sol-gel method as nitrogen doping (N) to obtain N-TiO2/Ti electrodes. The test results obtained that TiO2/Ti electrodes are only active in UV light and N-TiO2/Ti electrodes can be active in visible light. Determination of the COD value of the flow system for glucose and potassium hydrogen phthalate at various concentrations respectively of 5, 10, 20, and 30 ppm was carried out using the Multi Pulse Amperommetry (MPA) technique. The results of the COD sensor measurement of the flow system on the potassium hydrogen phthalate and glucose obtained light currents increase in proportion to the increase in concentration, which is also significantly proportional to the increase in COD value. The highest COD values for glucose and potassium hydrogen phthalate were at concentrations of 30 ppm respectively of 29.73 and 31.34 mg/L O2 using TiO2/Ti electrodes and for N-TiO2/Ti electrodes respectively 30.91 and 29.20 mg / L O2.
Photoelectrocatalytic performance of ilmenite(FeTiO3) doped TiO2/Ti electrode for reactive green 19 degradation in the UV-visible region
Authors: Azis T , Nurdin M , Riadi L S , Arham Z , Irwan I , Salim L O A , Maulidiyah Maulidiyah
Published: May 2021

FeTiO3 doped TiO2/Ti eletrode synthesized through a sol-gel and dip-coating methods for Reactive Green 19 (RG-19) degradation under UV-Visible irradiation. The electrode was characterized by Scanning Electron Microscope (SEM), Linear Sweep Voltammetry (LSV), and Multi Pulse Amperometry (MPA). The electrodesurface show that a FeTiO3 layer is quite thin and evenly distributed on the surface of the TiO2/Ti electrode. The photocurrent responses of TiO2/Ti and FeTiO3 doped TiO2/Ti showed the TiO2/Ti electrode was active in UV light, while FeTiO3 doped TiO2/Ti was active in the visible light. The optimum condition show that the TiO2/Ti dopedFeTiO3provided RG-19 degradation activity of 95%.
High photoelectrocatalytic activity of selenium (Se) doped TiO2/Ti electrode for degradation of reactive orange 84
Authors: Muzakkar M Z , Maulidiyah M , Ningsi N , Salim L O A , Istiqamah R N , Musdalifah A , Nurdin M
Published: May 2021

Studies on the synthesis of TiO2/Ti doped Se electrode to degrade reactive orange 84 (RO 84) compounds under UV-Visible irradiation have been successfully carried out. The research objective is to obtain the Se-TiO2/Ti electrodes and test performance in degrading RO 84 under irradiation of UV-Visible light by photoelectrochatalytic. Se-TiO2/Ti electrode were prepared by anodizing and dip coating methods. XRD analysis of TiO2/Ti electrode showed the formation of anatase crystals. The surface morphology of the electrode showed the nanotube structure while the composition of the elements in the electrodes was determined by EDX and the presence of selenium was detected at 0.80%. The characteristics of using Linear Sweep Voltammetry (LSV) show that TiO2/Ti electrodes are active in UV light, while Se-TiO2/Ti electrodes are active in visible light. Electrode activity test in degrading RO 84 showed that the Se-TiO2/Ti photoelectrocatalis performance with variations in UV and irradiation of visible light was good in integrating RO 84 with a degradation rate of 98%.
Degradation test of organic congo red compounds using Mn-TiO2/Ti electrode by photocatalytic under the uv-visible iradiation
Authors: Nurdin M , Maulidiyah M , Syahputra R A , Salim L O A , Wati I , Irwan I , Mustapa F
Published: May 2021

Preparation of TiO2/Ti and Mn-TiO2/Ti electrodes was successfully carried out. The purpose of this study was to effect the addition of manganese (Mn) to TiO2 which will be used to degrade congo red organic compounds by photocatalysis. TiO2 is made through an anodic oxidation process. Mn coating is done by doping using the electrodeposition method. The results of the characterization using XRD showed that the TiO2/Ti electrodes were produced in the form of anatase crystals. SEM results show that nanotubes formed on the surface of the thin layer of TiO2/Ti. EDX results show the presence of manganese metal on the surface of TiO2/Ti of 6.58%. The characterization results using LSV showed that the TiO2/Ti electrode was active in UV light at a concentration of 1 ppm with 51.23% degradation and the Mn-TiO2/Ti electrode was active at Visible light at a concentration of 1 ppm with 75.48% degradation.
Bacterial from wawolesea hot springs: crack sealing application to concrete
Authors: Susilowati P.E. , Zaeni A. , Kartini S. , Rajiani N.A. , Hermawan H. , Sudiana I. N
Published: May 2021

Concrete is one of the most widely used construction materials for infrastructure, but concrete has the disadvantage of being easy to crack. One of the factors that influence concrete cracks is rain water, because water can enter and seep into the pores. Several studies have been carried out to overcome the cracking of concrete structures; one of them is the addition of bacteria that have calcium carbonate precipitating activity. Calcium carbonate from bacterial metabolism can closed on cracked concrete surfaces. This method is commonly called Microbial Induced Calcite Precipitation (MICP). The source of bacteria in this study is bacteria at Wawalosea hot springs from the limestone mountain. The research is healing of cracks in concrete compare by bacteria MICP and MICP immobilization using alginate-chitin. The results showed that the concrete made with the addition of MICP isolates as much as 1.6x108 cells / mL had a greater compressive strength than the concrete without the addition of isolates. The value of compressive strength and absorbency of concrete water with the addition of MICP isolates has a compressive strength of 25.78 Mpa and addition imobilization MICP has 18 Mpa. So when compared to concrete without the addition of isolates and concrete with the addition of MICP isolates, the value of concrete compressive strength occurred at 100%.
Identification of sea urchin gonads chemical compounds using thin-layer chromatography from Bokory island, Southeast Sulawesi
Authors: Karmilah  , Musdalipah  , Daud Nur Saadah , Reymon  , Fauziah Yulianti
Published: May 2021

Southeast Sulawesi is one area that has a diversity of potential marine biota as medicinal ingredients, including the sea urchin gonads. Empirically coastal communities have been hereditary, consuming sea urchin gonads as a source of high protein. Considering its potential as a raw material for medicines, it is necessary to conduct a series of tests to guarantee its safety and efficacy. This study aims to determine the chemical compounds of sea urchin gonad extract (Diadema setosumL) by Thin-Layer Chromatography (TLC). The research method uses a Pre-experimental design with a one-shot case study model. Identification of metabolites of sea urchin gonad extracts was carried out in two stages: phytochemical screening and identification by TLC method by UV-Vis. Samples were dried by the Freeze-drying method to get 335.11 g of dry samples and 58.06 g of extracts. The results of the test of the content of water-soluble and ethanol-soluble sea urchin extract were 5.73% and 3.72%. The results showed that in phytochemical screening, ethyl acetate extracts of the positive marine gonads contained alkaloids, saponins, and steroids. In addition, UV-vis 254 nm and 366 nm TLC methods showed alkaloids and saponins. The Rf values are 0.4 and 0.68, respectively.
The search for dipeptidyl peptidase iv (DPP4) inhibitors for the treatment of type 2 diabetes: an in-silico study
Authors: Ruslin  , Al-Febriana K , Usman I , Arba M
Published: May 2021

Dipeptidyl Peptidase IV (DPP4) enzyme is a dissolved plasma enzyme found in the intestinal, kidney and liver capillaries that degrade the Glucagon Like Peptide-1 (GLP-1), which is crucial in regulating blood glucose levels. Thus, DPP4 inhibition was considered as an important strategy to combat diabetes. In this research, a pharmacophore modeling and molecular docking was conducted to identify the potential hits of DPP4 inhibitors. The pharmacophore features consisted of three hydrogen bonds acceptors and one positive ion with Area Under Curve of Receiver Operating Characteristic (AUC-ROC) were 0.72 and GH score of 0.592. Screening on the ZINC database resulted in 1151 hit molecules, in which all molecules were subjected to molecular docking to explore their binding interactions. The binding energies of all ligand were between -5.08 and -10.56 kcal/mol, in which four hit molecules, i.e. The four best hit molecules in term of binding orientation and binding energy were Lig_1418/zinc215387739, Lig_37/zinc7983247, Lig_1432/zinc100998449, and Lig_1037/zinc104157322, exhibited better affinities than that of cognate ligand (ABT341, E=-9.98 kcal/mol), which indicated their potentials as novel DPP4 inhibitors.
Synthesis of graphene-MnxOy nanocomposite as electrode sensors of profenofos
Authors: Azis Thamrin , Agusu La , Kadir L.A. , Rahmad Muh. Resky , A. Tenri L.O
Published: May 2021

Synthesis and characterization of of Graphene-Mnnanocomposites as Pesticide sensor electrodes have been carried out. This study aims to determine the method for synthesizing and characterizing the products of Graphene-Mnnanocomposite synthesis. Modification of Graphene using Mn nanoparticles for profenophos analysis with cyclic voltammetry. This research using with the Modified Hummers method and the liquid phase adsorption method followed by hydrothermal. Characterization of Graphene-Mn oxide nanocomposites are displayed using XRD, SEM-EDX and FTIR. The XRD results showed that there are peaks of Mn3O4 (30.57, 44.39), MnO2 (34.14), and MnO (39.85, 57.85, 68.94). SEM-EDX analysis reveals the surface of graphene sheets containing aggregates in shape small particles attached to graphene sheets. The results of the EDX analysis consisted of Mn 6.26%, C 53.60% and O. 15.45%. The FTIR test indicates the presence of Mn-O bonds in wave number 615.29 cm-1 and other functional groups, such as O-H, C-O, C = C, and C-H. Electrodes with the best composition at pH 6 will be used to detect pesticides profenofos with the Cyclic Voltammetry (CV) method at a scate rate of 0.05 V / s. The detection limit obtained from graphane-Mn measurements on profenofos is 0,000667 M. and the repeatability of graphane-Mn performance is 0.0131. The age of Graphene-Mn electrodes in analyzing profenofos pesticides is 17 days. The selectivity test using Pb (NO3)2 0.1M and Phenol 0.1M disrupting compounds occurred in a negative direction.
The antibacterial inhibition test of gonad sea urchin (diadema setosum) against the growth of staphylococcus aureus
Authors: Irma  , Tee Selfyana Austin , Fithria  , Muhammad Ilyas Y.
Published: May 2021

A The sea urchin is sea animal the rich in vitamin A, vitamin B complex and minerals to the smooth functioning of the nervous system and the metabolism of the human body. Gonad sea urchin contains flavonoids, steroids, triterpenoids, and saponins. This research was conducted to determine inhibition of antibacterial ointment sea urchin gonads against Staphylococcus aureus. The type of research conducted is experimental. This research used a cylinder cup method to measure inhibition zone of gonad sea urchin gonad. After incubation for 24 hours, measured inhibitory zone diameter around the cylinder cup. The results showed that the sea urchin gonads ointment have inhibitory effect on the growth of Staphylococcus aureus bacteria with broad average inhibition zone produced at a concentration of 2% at 2.47 mm, 4% of 1.62 mm, and a concentration of 6% has inhibitory zone Of 1.12 mm, and a positive control of 11.55 mm and the negative control does not provide a drag zone. Based on the ANOVA test results can be concluded that the F test = 0.691 <F table = 3.48 to 0.05, this means significant treatment 3 repetitions in each of the samples showed that there was no significant difference for F count is smaller than F table.
Ethanol and Sugar Production from Sorghum (Sorghum bicolor) Starch at Varying Acidity
Authors: Hadiyanti Nugraheni , Putu Ngurah Wijaya I , Saptorini  , Kustiani Edy
Published: May 2021

Sorghum (Sorghum bicolor), in addition to producing foodstuffs, feed, industrial use, is also potential for ethanol production. Sorghum is also a potential developed because it has a complete adaptation power in marginal land and other non-productive lands. The use of sorghum starch for ethanol production is a renewable fuel alternative and friendly for the environment. The aim of the research was to study the fermentation of sorghum starch into simple sugars and ethanol at varying acidity (pH). The study is experimental research with two treatment factors: pH (4; 6; 7; 8; 9; 10) and sugar levels. Data were collected and analyzed with simple and multiple linear regression analyses. The result showed that the pH treatment applied to influence the enzyme fermentation of sorghum starch. The conclusion of the study is the optimum pH of amylase enzyme activity in fermenting sorghum starch into glucose is pH 8. The relationship between the amount of alcohol, sugar, and pH is very strong at 95.1%. Multiple regression equations to explain the relationship of the three variables that the amount of alcohol (Y) produced in sorghum starch fermentation can be estimated additive by the amount of sugar formed (X1) and pH (X2).
Precipitation Method in Calcium Phosphat Synthesis from Blood Clamshells (Anadara Granosa)
Authors: Nurma Wahyusi K , Karunia N , Satrya M
Published: May 2021

Sources of calcium phosphate can be produced from materials containing calcium carbonate (CaCO3). These materials are usually found in clamshells, eggshells and limestone. Calcium phosphate can be produced by chemical precipitation by reacting calcium carbonate (CaCO3) from a material containing CaCO3 with HCl and then reacting again with Na2HPO4 and calcium phosphate Ca3(PO4)2 is obtained. In this study raw materials used for blood clamshells waste. Precipitation is a method which results in the formation of solids in solution or in other solids during chemical reactions. From the results of XRF analysis it can be seen that the best results entered in the classification of calcium phosphate are at pH 8 with a stirring time of 3 hours and pH 9 with a stirring time of 4 hours there is a Ca/P value of 1.5. At the Ca/P value it forms Tricalcium Phosphate. There are 3 types of Tricalcium Phosphate which are α, β and amorphous. It can be concluded that the longer the stirring time and the pH value increase, the Ca / P value also increases. To form TCP (Tricalcium Phosphate).
Antioxidant Potential of the Shell of Razor Clams (Solen spp) in Antidiabetic Mellitus Type II Therapy
Authors: Anggarani Mirwa Adiprahara , Purnama Erlix Rakhmad , Dalilah Aziz Jihan Shofwatul Islam
Published: May 2021

Razor clams (Solen spp) are one type of bivalves found in Madura waters and suggested to have antioxidant bioactive compounds. This research was conducted to determine the chemical compounds and antioxidant activity as well as testing blood sugar levels on mice that are conditioned to suffer from diabetes mellitus. The extraction method used is stratified by using three solvents which have different polarity. The test being done was phytochemistry tests to determine the bioactive compounds contained in the shell of razor clams, DPPH method to determine antioxidant activity, and blood sugar test in mice. The crude extracts of the shell of razor clams is contained alkaloid and saponins The highest antioxidant activity (IC50) was found from the shell of razor clams extracted eith ethanol was 489.56 ppm. The results of the blood sugar test showed that the addition/consumption of antioxidant extract of razor clams of 0.0063g/20g body weight (BW) was able to reduce blood sugar levels of mices with diabetes mellitus type 2.
Study on Flood Simulation of Tallo Watershed, Makassar City, South Sulawesi Province
Authors: Musliadi  , Chaerul M , Gusty S
Published: May 2021

Tallo watershed has a length of 70 km, its area width is 407.00 ¬¬km2, the river upstream or downstream is at an altitude of ± 1,100 m above sea level located on Mount Kaliapolompo in which the overall length of the river in Tallo watershed totaling ± 131.50 km2. The research objective was to analyze the effect of five-year flood discharge and tidal changes on the inundation area and flood depth in Tallo watershed. The method of rainfall analysis used the Log Pearson type III method where the flow is considered to be two horizontal dimensions with even velocity at each depth. A five-year period with a discharge value of 127.64 m3/s will statistically reoccur every five years with an estimated chance of occurrence of 0.2 or 20% for each year referred to in a 5-year review cycle. The results of the simulation were then known that the five-year flood discharge resulted in flooding with a depth of 0-3 meters from the maximum tide condition (HWSL), and an inundation area of 31.91 km2 inundated the Tallo District, Tamalanrea District, Panakukang District, West Biringkanaya District and northern Manggala District. These areas are located on the left and right of the Tallo River with an altitude between 0 and 2 meters above sea level.
A general framework of covid-19 model with control strategies: the application of large-scale social restrictions, self-quarantine, and immune system improvement in Surabaya, Indonesia
Authors: Artiono Rudianto , Yunianti Dwi Nur , Prawoto Budi Priyo , Astuti Yuliani Puji
Published: May 2021

A covid-19 is a virus disease of worldwide importance which spread not only in a small country such as Mongolia but also in a large country like the United State. It is caused by a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and well known as droplet-borne disease. The droplets containing coronavirus are spread through the air within a meter and deposited on the mucous membranes of suscpetible person. The aim of this study was to produce a general framework model of corona virus disease with the application of large-scale social restriction, self-quarantine and immune system improvement as control strategies to reduce the spread of the disease. This study was conducted in Surabaya, Indonesia with a total of 299 positive patients infected with covid-19 until the fourth week of April, 2020. The transmission routes of the disease had been constructed based on the real problem. Therefore, human population have been divided into some sub-population based on the characteritics of disease symptoms. The spread of covid-19 have been formulated mathematically by using compartment model. Stability analysis had been done for a free disease equilbrium and an endemic equilibrium. Moreover, numerical simulation were also provided to quantify the disease dynamics.
Regional Overview of Food Security from Two Dimensions: Availability and Access to Food, East Java Province
Authors: Lisanty Nina , Andajani Wiwiek , Pamudjiati Agustia Dwi , Artini Widi
Published: May 2021

Food security has always been a topic of keen interest to policy-makers, practitioners, and academics worldwide. In the operational sense, food security concerns the availability, accessibility, and stability of its procurement. The leading indicators of food security at the household level access (physical and economic) to food, food availability and risks associated with food access and availability. A study was conducted by utilizing data from several government institutions to examine the level of regional and household food security of East Java Province. The result showed that the food security level of East Java Province has increased between 2010 and 2017, mainly because of improvements in several indicators of food security and nutrition. However, two main challenges require serious attention, namely: a) increasing economic access to food, mainly through increased investment and infrastructure and b) addressing increased vulnerability to the risk of climate change. In conclusion, this paper discusses information and suggestions to improve the food security level in the province, including approaching programs and policies related to the issues.
Factors Affecting Rice Production
Authors: Ginting Nina Maksimiliana , Andari Gardis
Published: May 2021

This study aims to look at the factors that affect rice production. This research was conducted in Tanah Miring District, Merauke Regency. Site selection is done deliberately (purposive). Sampling using Purposive methods as many as 88 farmers. The data used in this study include primary data and secondary data. Data were analyzed using Multiple Linear Regression Analysis. The coefficient of determination (R2) is 0.955. This coefficient of determination shows that rice production (Y) can be explained by seed variables (X1), fertilizer (X2), pesticides (X3), and labor (X4) by 95.5% while the remaining 4.5% is influenced by factors others are not included in the equation. Significant value of F equal to 0,000, namely seed variables (X1), fertilizer (X2), pesticides (X3), and labor (X4), simultaneously have a significant effect on rice production variable (Y). Partially, seeds and pesticides affect rice production while fertilizer and labor do not affect rice production. The classic assumption test shows that there are no multicollinearity, heteroscedasticity symptoms and normally distributed regression models.
Performance Study of Regional Water Supply Company of Ternate City, North Maluku
Authors: Nagu Nani , Ahadian Edward R , Latif Lita A. , Fabanyo H
Published: May 2021

Regional Water Supply Company (RWSC) of Ternate City is a company managed by the local government which in its operation needs to prioritize the fulfillment of clean water for communities. Therefore the services of RWSC should based on the standards of quality service provided by the National Agency for the Improvement of Drinking Water Supply System. On the other side, the demand for clean water supply and services is increasing every year. This is caused by an increase in population and the development of cities or service areas relating to the improvement of the socio-economic. The purpose of this study is to evaluate the performance of water supply service providers in Ternate City. Data analysis based on the guidelines from the National Agency for the Improvement of Drinking Water Supply System involves several indicators such as the financial aspects, service aspects, operational aspects, and aspects of human resources. The result shows that the score of the financial reaches 0.92, the service aspect 0.88, the operational aspect 0.88, and the human resource aspect 0.52. These results show that the performance of Regional Water Supply Company (RWSC) of Ternate City achieves score 3.2 and it indicates that the performance of Regional Water Supply Company (RWSC) of Ternate City in the healthy category.
Preliminary Study of Digital Manufacturing Requirement for Kampus Merdeka Apprenticeship Program
Authors: Rachmat  , Nugraha Syaiful , Prihandoko LA , Marsujitullah  , Suwarjono
Published: May 2021

Students are allowed to take courses outside campus in the Kampus Merdeka program. In this regard, students need to be equipped with competence related to digital industries’ needs, especially for computer science students. The purpose of this research is to conduct a preliminary study of the abilities needed by the student to execute the Kampus Merdeka program base on stakeholders’ perspectives, who specifically are digital manufacturing in Papua. This research is a quantitative study that employs a survey strategy. Respondents came from various fields related to digital manufacturing, including banks, government offices, private companies, and digital start-ups. The online questionnaire was distributed, and 100 respondents gave responses related to the abilities students must possess for digital manufacturing field working. The findings of this study underline several essential abilities, including industry 4.0 framework knowledge, digital usage skills, and information communication technology (ICT) skills. The findings of this study contribute to a better understanding of the technical capabilities required by stakeholders. The results of this study can be developed into a policy of aligning the capabilities of students with digital manufacturing needs.
Analysis of resources allocation on passenger ship reparation project using work breakdown structure method in pt. xyz
Authors: Rivanda Fristy Novia , As’adi M , Montreano D
Published: May 2021

Each project generally conducts planning and makes a project schedule, when the project should start and completed, how the project will be carried out, and how to provide its resources. Resources are one of the factors that affect the project’s limited amount of profit. So we need a careful and good planning with limited resources in implementing the project in order to use resources efficiently. The purpose of this study is to evaluate the reparation project planning so that there are no more delays in the project by detailing the work package through the Work Breakdown Structure (WBS) method, which in previous studies showed that there was a delay of 4 days using the S-curve. The study was carried out on the KMP (Passenger Motor Ship) repair project at the shipyard PT. XYZ The type of research method used is descriptive qualitative case study approach and purposive sampling. Research methods are using Fault Tree Analysis (FTA) to determine the triggering factors for delays, Critical Path Method (CPM) to determine critical paths, Work Breakdown Structure (WBS) to determine the division of work package levels, WBS dictionary for job identification and resource requirements. Obtained a percentage of 91.3%. Due to the result of work package similarities is x ≥ 75%, there is a tendency for the work package of the WMP KMP Dictionary to further the KMP Repair Project.
Islamic Banking Third-party Funds Grouping uses the Data Mining Clustering
Authors: Hidayat S , Irwansyah R
Published: May 2021

Islamic banking as an intermediary institution (intermediary) between people with excess funds and people who lack funds has a very important influence on the Indonesian economy. In this study, the third-party funds discussed were third-party funds of Islamic banking. The purpose of this study is to analyze the grouping of Islamic banking third-party funds on Indonesia’s economic growth over the past 11 years, from 2009 to 2019 using the K-means algorithm. The data of this study uses time-series data from Islamic banking statistics, namely data on third-party funds for Islamic banking financing sourced from the official website of the Financial Services Authority. The findings of this analysis are in the context of a clustering of Islamic banking third-party funds containing 2 clusters: low (C1) and high (C2). The results obtained are there are 7 data with low clusters and 4 data with high clusters. The results of calculations carried out manually and testing using Rapid Miner, produce the same data grouping.
Description of Probability and Randomized Events Literacy for Statistics Student at Universitas Negeri Makassar
Authors: Tiro M A , Aswi  , Sudarmin
Published: May 2021

The concept of probability and randomized events is the main basis of statistics. Thus, literacy of probability and randomized events is a basis of statistical literacy. This study aimed to describe and assess the literacy of probability and randomized events for students of the statistics department of the first (2013) and the second (2014) batch at Universitas Negeri Makassar. Statistical literacy is defined in four indicators namely understanding the concept; the ability to apply; the ability to calculate; and interpretation skills of probability and randomized events. The approach used for the analysis of this survey data were descriptive quantitative and classification. Classification analysis was used to determine problems classification faced by students in probability and randomized events literacy. A confirmatory factor analysis was used to see the validity of the construct operational definitions of the variables. This study found that the level of probability and randomized events literacy achieved by statistics students at Universitas Negeri Makassar is categorized medium, pointing to the need for increased learning strategies that emphasize the four basic competencies.
Global Stability Analysis of Dengue Transmission Model with Awareness, Vector Control and Time Delays
Authors: De Lara-Tuprio Elvira P. , Teng Timothy Robin Y. , Macalalag Jay Michael R.
Published: May 2021

In this paper, a mathematical model for a single-strain dengue virus transmission, incorporating vector control, disease awareness of susceptible humans, and both the latent delays for human and mosquitoes, is proposed and studied. The global stability properties of disease-free equilibrium and endemic equilibrium are completely established through Lyapunov functionals and LaSalle’s invariance principle. The global dynamics of the equilibrium points are characterized by the value of basic reproductive number R
0. If R
0
< 1, then the disease-free equilibrium is globally asymptotically stable. If R
0
> 1, then the disease-free equilibrium is unstable, and the endemic equilibrium exists which is globally asymptotically stable. Lastly, this paper presents numerical simulations and possible recommendations for future works.
A diffusion and osmosis system with bounded nonlinearity
Authors: Suratman Dede , Soeharyadi Yudi , Cahyono Edi , Arbi Lukman H.
Published: May 2021

A diffusion and osmosis system of ordinary differential equation is considered. The system may represent migration of finite particle among finite places. Such system in the linear form yields a solution in the form of matrix exponential. In this paper, a bounded nonlinear forcing to the system is considered. Although it is bounded, the nonlinear affected so much to the solution. Numerical simulation of some two-dimensional examples are presented. Understanding the diffusion and osmosis system will be important for studying migration people among towns, cities or countries.
A survey to estimate the proportion of Southeast Sulawesi elementary school students reading fluently
Authors: Wibawa Gusti N.A. , Somayasa Wayan , Yahya Irma , Hidayat Ahid , Abapihi Bahriddin
Published: May 2021

We conducted a survey to estimate the proportion of elementary school students in Southeast Sulawesi who have been able to read fluently while sitting at second grade. The information is needed to contribute to the policy towards enhancement of elementary student ability to read in their early stage of schools. A two-stage cluster sampling method had been applied in order to maintain the representativeness of selected samples over the whole population. At the first stage, we randomly chose the districts and, then, randomly selected the sub-districts. Finally, all elementary schools in each selected sub-district were taken as well as all their second grade students as the sampling units. Doing these, wegot 230 respondents randomly selected from 78 elementary schools of 20 sub-districts in all 6 selected districts or regencies. Based on the selected samples, it is approximately only 32% of students were able to read fluently, while the rest of them were unable or less abilityto read.
Parameter estimation for high dimensional classification model on colon cancer microarray dataset
Authors: Abapihi Bahriddin , Mukhsar  , Adhi Wibawa Gusti Ngurah , Baharuddin  , Lumbanraja Favorisen Rosyking , Faisal Mohammad Reza , Sani Asrul
Published: May 2021

In classification problems, logistic regression is among powerful techniques for discrimination. It provides directive probabilities of sample classification and interpretable coefficients. When it comes to model high dimensional dataset, however, logistic regression with its Newton-Raphson method of parameter estimation is no longer applicable, especially on low sample size and extremely high dimension. By applying cross-entropy algorithm on regularized logistic regression, it was able to well performing parameter estimation and highly accurate classification result.
Advanced hill cipher algorithm for security image data with the involutory key matrix
Authors: Supiyanto  , Mandowen S A
Published: May 2021

The security of important and confidential data is a top priority. Therefore, it is necessary to secure appropriate data to ensure confidentiality. Secrecy of data security can be done by randomizing the data in order to make the data is difficult to understand by anyone. One of the data security techniques that can be used is Advanced Hill Cipher cryptography. The purpose of this research was to create an application or software used to secure an image’s data by applying the Advanced Hill Cipher algorithm. A classic cryptographic technique, which use a matrix as a key in the process of encrypting and decrypting data with the type of key used is the symmetric key type. The data used in this study was an image data, while the application development used the language of MATLAB Programming. The method used in this study was the Advanced Hill Cipher Cryptographic Algorithm. Basically the Advanced Hill Cipher Cryptography algorithm is much more like the Hill Cipher algorithm. However, on Advanced Hill Cipher, algorithms are developed using a key matrix that always has inverse; so that the disadvantages of the hill cipher algorithm are that the key matrix does not always have inverse resolved. In this research, the key matrix used is a 2x2 order involuntary matrix with integer elements. The output of this study is anapplication that can be used to encrypting and decryptinggrayscaleand color image data with key matrix that always have inverse.
An automated cognitive analysis model for online asynchronous discussion
Authors: Tenriawaru Andi , Rahman Abdul
Published: May 2021

Evaluation of students’ cognitive abilities needs to be done as part of evaluating student learning outcomes. This evaluation must not only be done in conventional learning, but this must also be done in online learning. Evaluation of students’ cognitive abilities can be done through cognitive evaluation of messages posted by students in online asynchronous discussion. There are several studies that have addressed the problem of evaluating students ‘cognitive abilities in on-line learning, but the process of identifying students’ cognitive abilities in these studies has not been fully automated. There are parts of the identification process still carried out by humans. This study proposes a model that can produce classification automation of cognitive levels of messages posted by students in online asynchronous discussion. The messages used in this study are messages written in Indonesian. The proposed model consists of four main processes, namely the process of creating corpus, extraction and selection of features, classifier and training development, and testing. This model can help lecturers to identify cognitive levels of messages. The proposed model is expected to improve the performance of evaluation systems of e-learning learning.
Application of Cauchy-Schwarz inequality method for resolving constrained optimization problems at classroom with formal pre-operational phase of thinking
Authors: Samparadja Hafiludin , Agusu La
Published: May 2021

The optimization problem is a mathematical problem that is introduced at the junior high school level. Material related to optimization has even been introduced for elementary school levels in students with a level of concrete operations, especially for students who are prepared to take part in the Math Olympiad. The problem arises here, is that complicated methods for finding solutions to optimization problems, such as the simplex method, ordinary differential equations, partial differential equations, and the Lagrange multiplier were only introduced in high school or in college. To bridge this we need a special method that is easily understood by students participating in the pre-Olympic who are at the level of formal preoperative cognition, one of these methods is called the Cauchy-Schwarz inequality method. The Cauchy-Schwarz inequality is a powerful tool for finding the maximum and minimum solutions for a target equation with one or two constraint equations. The interesting thing is that the prices of the optimum manufacturing variables are reached when the Cauchy-Schwarz equation is fulfilled.
Synthesis of Precipitated Calcium Carbonate (PCC) as a Raw Paramagnetic Material Based on Ferrite-Calcite (Fe-CaCO3) and Its Potential Application
Authors: Nurhayati N , Sujiono E H , Zharvan V , Saleh M , Awiseng A T , Nursetya M F
Published: May 2021

Precipitated calcium carbonate (PCC) has been conducted by solid-liquid-gas route process. The PCC powder was prepared from limestone from lime powder contain dolomite as raw material and 0.5 M of glucose solution. The PCC powder then characterized using XRD to identify the phase and FTIR to identify the functional group. Further analysis shows that the PCC have one major phase CaCO3with peak characteristic at 2θ = 29.3°also the FTIR spectra shows the presence of CaCO3at 871.70 cm−and 1397.23 cm−.
Investigating the effect of pyro-catalytic temperature on gasoline production from low density polyethylene (LDPE) plastics waste
Authors: Jahiding M , Rizki R S , Hasan E S , Mashuni
Published: May 2021

This research aims to produce hydrocarbon fuels from LDPE plastic waste by the pyro-catalytic method. Pyro-catalytic of LDPE samples was carried out at 400, 425, 450, 475, 500, 525 and 550 °C, heating flow rate of 15 °C/min with zeolite catalyst. Fuel-oil quality analysis includes: density, viscosity, heat value, and hydrocarbon compounds using Gas Chromatrography-Mass Spectrometry(GC-MS). The pyro-catalytic process at temperatures of 400, 425 and 450 °C did not produce fuel oil, while at 550 °C it produced wax, so that the analysis of the quality of fuel-oil was not carried out. At pyrolysis temperatures of 475, 500 and 525 °C, respectively: bio-oil yield 8.4; 25.6; 46.5%; viscosity 0.81; 0.75; 0,84cP, density 0.750; 0.764; 0.756 g/mL and the caloric value of 11,403; 11,421; 11,338 kcal/kg.GC-MS spectrogram analysis of fuel-oil obtained the highest gasoline (C5-C12) content at pyrolysis temperature of 500 °C which was 81.31%.Based on the physical characteristics and percentage of the gasoline compounds content, this study recommends the production of fuel-oil from pyrolysis LDPE with zeolite catalytic done at a temperature of 500 °C because it is in accordance with fuel characteristics standards according to the American Standard and Testing Materials (ASTM).
Implementation Development Teacher Certification Program in Universitas Negeri Makassar
Authors: Khaeruddin  , Annas S , Awi
Published: May 2021

The pedagogic competence being tested is the integration of pedagogical concepts into the learning process of the field of study in the classroom. Meanwhile, the professional aspect is the basic competence in the field of study tested in accordance with the academic qualifications of the teacher, namely the ability of the teacher to plan and implement the learning process. Related to that, the results of this TCT could be influenced by several factors, including the quality of the input for Teacher Certification Program (TCP) implementation in the Institute of Teachers’ Education (ITE), the quality of the TCP implementation process in the ITE, the quality of the output of TCP implementation in the ITE, the internal quality assurance system for the Study Program organizing TCP in the ITE, and the TCP implementation model in the ITE. Therefore, it is necessary to study the input, output, process, Internal Quality Assurance Standards, and the implementation model of MIPA TCP in ITE.
A Development of IPA (Natural Sciences) Learning Tools Based on Investigative Approach in Empowering Students’ Higher-Order Thinking Skills and Concept Mastery in Junior High School
Authors: Danial M , Yunus M , Syamsir M , Rahmania
Published: May 2021

The major objectives of this research were to produce valid, practical, and effective learning tools of IPA subject which are able to empower higher-order thinking skills (HOTS) and students’ concept mastery in junior high school. There are several specific aims such as: 1) obtaining IPA learning tools for seventh grade students of junior high school in terms of investigative, potential and effective ‘acid-base’ materials to be implemented in the subject learning process for empowering students’ higher-order thinking skills and the concept mastery and 2) obtaining IPA learning tools in the form of investigative lesson plans (RPP), Student Worksheet, and Student’s Book for junior high school. This research applies research and development design, where development is carried out with reference to the 4-D model in particular define, design, develop, and disseminate. As for the research subjects, it involved 64 students and four IPA teachers which was conduceted at a junior high school in Makassar that is SMPN 36 Makassar. In connection with it, the stages of the research are defining, designing, developing, and disseminating which focus to obtain valid, effective and practical learning tools. As as result, this research: (1) produces investigative IPA learning tools which are valid, practical, and effective for junior high school; (2) obtains the learning tools’ validity level as 3.84 which is classified as strongly valid, the practicality level of teachers’ responses aspect as 91.28 with positive response category, the implementation level as 1.83 with implemented category, and the ability to manage learning as 3.63 with excellent category; and (3) the level of effectiveness for critical thinking skills as 85.17 with high category, problem-solving ability as 74.50 with high category, and concept mastery as 82.78 with high category, and the percentage of learning completeness as 85.41% with very high category. Thus, this research produces a valid, practical, and effective IPA learning tools in empowering students’ higher-order thinking skills and the concept mastery of ‘acid-base’ materials for junior high school.
Conceptual Thinking Profile of Mathematics Education Department Female Student in Solving Problems
Authors: Hamda  , Ketut Budayasa I , Lukito Agung
Published: May 2021

This research described the conceptual thinking of female student in solving math problems. The research subject was a female student of Mathematics Education who had the upper middle category of mathematics ability. This research was an exploratory research with a qualitative descriptive approach. The data were collected through problem solving tasks and in-depth task-based interviews. The validity of the data was done through continuous observation, time triangulation, and member check. Data analysis was carried out through several stages, namely data categorization, data reduction, data presentation, data interpretation, and conclusions. The results showed that in understanding the problem, the female student made symbolic and pictorial representations separately. She mentioned the concept while drawing. In making plans, the female student’s strategies were based on certain concepts and were related to problem questions, so that the plan of solving steps was not yet complete. In implementing the plan, the female student determined the initial steps for solving certain concepts that can be resolved and linked them to the problem questions. She did the problem solving partially based on the relationship between concepts, so that the problem solving steps were less systematic.
The Mathematical Proof Steps of Mathematics Study Program Students in the Subject of Real Analysis
Authors: Minggi I , Arwadi F , Sabri
Published: May 2021

the present paper describes the second year-research entitled the learning trajectory on mathematical proof of the students majoring in mathematics education. It applies the product of the first-year research namely the framework of the learning trajectory of mathematical proof and the design of its means in the topic of the real number system and the real number sequence. The present research aims at obtaining the mathematical proof steps in the learning trajectory which has been already set in the first-year research. Design research was determined as the research method aimed at, according to Gravemeijer (2013), developing a Local Instruction Theory (LIT). The LIT is expected to improve the quality of learning by developing the sequence of activities and understanding the empirical phenomena about how something works. In this research, the steps of mathematical proof were hypothetically designed i.e., (1) understanding the statement which will be proved, (2) deciding to choose either direct proof or indirect proof, (3) writing the proof specifically, and (4) verifying the validity of the proof. After the activities had been applied, retrospective analysis was undertaken to identify whether the stages were in line to the learning trajectory set in the first-year research. The learning trajectory itself includes: (a) proof with simple procedures of which the proof of a statement is done with single thinking procedure, (b) existential proof covering existential proof and non-existential fact or concept, (c) proof with complex thinking procedure, and (d) proof through construction, The findings suggest that the steps of the previously hypothesized proof occur with a support which is called scaffolding by visualizing a diagram of proof as the guide for writing the proof and there are still difficulties of writing the proof symbolically and describing mathematical argument which relates each step of the proof process.
Students’ Factual Understanding on the concept of Limit
Authors: Arsyad N , Ramadhana Y. , Assagaf S. F.
Published: May 2021

This research aims to describe the factual understanding of the concept of the formal definition of limit. This is a descriptive qualitative research with 8 students. The data gathered by using test and interview. The instruments is a conceptual understanding test. We divide the factual understanding into three main concepts: (1) students’ understanding on the symbol of ε and δ in the definition, (2) students’ understanding on the meaning of the absolute value in the definition, and (3) students’ understanding on the implication statement in the definition. Each elaborate to some categories to get the ideas on how students understand about the concept. The results reveals that most students have incomplete understanding about the definition of limit function.
Teachers’ Content Knowledge (CK) Analysis and Students’ Performance on Fractional Materials: A Case Study in Al-Amien Prenduan Foundation School
Authors: Wijayanti P , Kutub A H W , Fardah D K , Ismail
Published: May 2021

Fractions is one of the richest and most complex mathematical topics in mathematics learning. This is caused fraction topics is being one of the difficult topics in learning mathematics. Therefore, this study aimed at analyzing Teachers’ Content Knowledge and Students’ Performance on fraction topics. This research is a qualitative descriptive study which is a case study of Teachers’ Content Knowledge and Students’ Performance on fractional materials at the Al-Amien Prenduan Foundation School, Sumenep, Madura, East Java, Indonesia. Data were taken from 29 students of 7th grade and 2 teachers who taught these students. The instrument used in this study was 3 fraction problems. Data collection techniques are carried out using tests and in-depth interviews to obtain information in detail. The results of this study are the similarity of the patterns found in students’ and teachers’ performance on fraction topic. Teachers deliver the concept of fractions by emphasizing on students’ performance that is procedural rather than students’ understanding. These methods result in students learn fractions by memorizing them so that misconceptions can occur.