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Jurnal Ilmiah Sains
Published by Universitas Sam Ratulangi
ISSN : 14123770     EISSN : 25409840     DOI : https://doi.org/10.35799/jis.v22i2.40961
Core Subject : Science, Education, Agriculture,
Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemistry Computer Science & IT Mathematics Physics
Jurnal Ilmiah Sains (Journal of Scientific Sciences) is the Journals Published by Faculty of Mathematics and Natural Sciences, Sam Ratulangi University. Jurnal Ilmiah Sains Published Twice a Year, i.e April and October. Jurnal Ilmiah Sains  welcomes full research articles in the area of Mathematics and Natural Sciences from the following subject areas: Mathematics Statistics Computer Science Physics Chemistry Biology
Arjuna Subject : Umum - Umum
Articles 309 Documents
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Effect of Red Bajakah Tampala Flavonoid Concentration as Antibacterial on Bacillus subtilis Devika Khoirul Hafifah; Suparno Suparno
Jurnal Ilmiah Sains Volume 23 Nomor 2, Oktober 2023
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/jis.v23i2.49392

Abstract

Red bajakah tampala (Spatholobus littoralis Hassk.) is one type of bajakah that the Dayak people use as traditional medicine. Red bajakah tampala roots contain chemical compounds, namely flavonoids, which have antibacterial activity. This study aims to determine the effect of flavonoid concentration of red bajakah tampala root extract on the inhibitory power of Bacillus subtilis bacteria and the length of survival time. Bajakah root extract is obtained by decoctation method. The flavonoid content contained in bajakah extract was determined using the visible spectrophotometric method. The particle size was determined by a particle size analyzer (PSA), and the inhibition was tested by the Kirby Bauer technique. In an effort to identify bajakah root extract, density, viscosity, and refractive index were measured. The test results using the visible spectrophotometric method showed that the sample had a flavonoid concentration of 16.28 ppm. Meanwhile, the PSA test results showed that the particle size of bajakah extract was 94.6 nm. The antibacterial test results showed that the diameter of the clear zone increased from (6.23 ± 0.03) mm to (7.18 ± 0.06) mm according to the increase in flavonoid concentration from 10 ppm to 30 ppm. The ability of bajakah extract to survive in inhibiting bacteria varied from 48 hours to 72 hours. The results of measurements of density, viscosity, and refractive index are (0,960  0,002) gram/cm3, (0,890  0,010) , dan 1,3350  0,0005 respectively. Keywords: Bacillus subtilis; decoctation; flavonoids; Red bajakah tampala
Analisis Risk Analysis and Tsunami Disaster Mapping in Mamuju, West Sulawesi Using TUNAMI-N2 Theresya Maharani Bandangan; Guntur Pasau; Gerald Hendrik Tamuntuan
Jurnal Ilmiah Sains Volume 23 Nomor 2, Oktober 2023
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/jis.v23i2.48143

Abstract

Mamuju City is an area that has extraordinary natural beauty and is often used as a tourist attraction, especially marine tourism. The potential for a tsunami disaster in this region is very large because it is located directly opposite the Makassar Strait which is the location of the center of tectonic earthquakes. This study aims to determine the maximum height of tsunami waves and the arrival time of tsunami waves that can hit Mamuju City and analyze the risks that occur due to the tsunami waves. The method used in this study was modeling using TUNAMI-N2 software. The results of this study showed that a tsunami with an earthquake magnitude of 7,2 and  7.3 Mw had a maximum wave height of 7,91 m and 8.04 m at the 18th minute with a very high risk. Keywords: Disaster; model; risk; tsunami
SEIR Model of Dengue Hemorrhagic Fever with the Life Stage Structure of the Aedes albopictus Mosquito James U.L. Mangobi; Santje Matulende Salajang; Cori Pitoy
Jurnal Ilmiah Sains Volume 23 Nomor 2, Oktober 2023
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/jis.v23i2.48235

Abstract

Dengue Hemorrhagic Fever (DHF) is an acute febrile illness caused by the dengue virus. This virus belongs to group B arthropod-borne viruses (Arboviroses) of the genus Flavivirus, which has four serotypes, namely Dengue I, Dengue II, Dengue III, and Dengue IV. Dengue virus is transmitted by Aedes sp. The SEIR model studied places the Aedes albopictus mosquito as the main vector. Many DHF cases are caused by this mosquito because it has a larger coverage area and is more difficult to control. All Aedes mosquito species have four life stages, namely: (1) egg, (2) larva, (3) pupa, and (4) adult. A stage-structured model was chosen because Ae. albopictus has varying rates of development and mortality at different stages. This model study includes determining the fixed point, determining the basic reproduction number R0, analyzing the stability of the fixed point, and simulating the population dynamics of dengue virus transmission. This model indicates the presence of endemics in an area for certain parameter values. This model produces a disease-free equilibrium, or DFE, which will be stable when R0 < 1, otherwise unstable when R0 > 1. The dynamic results for each human population (susceptible, exposed, infected, and cured) through observations in numerical simulations are influenced by the selection of the R0 value. The value of R0 is influenced by the mosquito death rate parameter and the average bite rate of infected mosquitoes. Population dynamics simulations show that an increase in the death rate of mosquitoes will reduce the number of humans exposed to them. In addition, an increase in the average number of infected mosquito bites will increase the number of humans exposed. Changes in the number of humans in each population tend to be different for each increase in the mosquito mortality rate or for each increase in the average number of infected mosquito bites.
Kernel Performance in Geographically Weighted Regression Model to Determine Factors Affecting Human Development Index in South Sulawesi Province Angelia Fransisca Adatunaung; Djoni Hatidja; Winsy Christo Deilan Weku
Jurnal Ilmiah Sains Volume 23 Nomor 2, Oktober 2023
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/jis.v23i2.48867

Abstract

The aims of this study was determine at kernel performance by selecting the best model from three different types of kernels and determining the factors that influence the Human Development Index in South Sulawesi Province using the Geographically Weighted Regression (GWR) model This study uses secondary data from the Central Bureau of Statistics of South Sulawesi Province with independent variables namely human development index (HDI, Y) and the dependent variable namely life expectancy (UHH) (X1), per capita expenditures (X2) and gross regional domestic product (GRDP) (X3) and the longitude and latitude values ​​obtained from the google maps application. The methods carried out in this study are the GWR method and the kernels used are gaussian kernels, bisquare kernels and tricube kernels. The results of this study show that the best model that can be used is the GWR model with a tricube kernel with AIC values ​​= 81.5543700 and R2 = 90.67 percent. GWR Model with kernel tricube is able to determine the factors that influence the human development index in South Sulawesi in 2022. Keywords: Geographically Weighted Regression; human development index; tricube kernel
Application of Nonparametric Spline Regression and Fourier Series to Model Gross Regional Domestic Product in Indonesia Marklif Esriy Mocodompis; Deiby Tineke Salaki; Djoni Hatidja
Jurnal Ilmiah Sains Volume 23 Nomor 2, Oktober 2023
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/jis.v23i2.48868

Abstract

The purpose of this study was to model the Gross Regional Domestic Product (GRDP) in Indonesia using nonparametric spline regression and Fourier series. The data used includes the GRDP of 34 provinces in Indonesia, with predictor variables such as labor force participation rate, foreign direct investment, local revenue, minimum provincial wage, and human development index. In the nonparametric spline regression, the determination of the optimal knot points is performed with one to three knots, and the optimal knot points are obtained by minimizing the Generalized Cross Validation (GCV) value, resulting in three optimal knot points. In the nonparametric Fourier series regression, calculations are performed for one to three oscillation points, and the optimal oscillation points are obtained based on the minimum GCV value, resulting in three optimal oscillation points. Therefore, the best nonparametric spline regression model utilizes three knot points, while the Fourier series model utilizes three oscillation points for modeling the GRDP in Indonesia. Keywords: Fourier Series; nonparametric regression; oscillation point; spline
Prediction the Number of Ship Passengers in Ports Tagulandang Using the Triple Exponential Smoothing (TES) Method Morisa Martha Kasawehi; Djoni Hatidja; Yohanes Andreas Robert Langi
Jurnal Ilmiah Sains Volume 23 Nomor 2, Oktober 2023
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/jis.v23i2.48886

Abstract

The purpose of this study is to predict the number of ship passengers at Tagulandang Port. The data in this study are secondary data taken from Class III Ulu Siau Harbor Master Office in the Tagulandang Working Area. In addition, the data used is the number of passengers departing from Tagulandang Port from January 2018 to December 2022. The analysis method used is the TES method which consists of two models, namely the additive model and the multiplicative model. After analysis, it is predicted that the number of departing passengers will increase in January and December 2023. Based on the prediction results, the most number of passengers will be in December 2023, which is 1354 people, which is predicted to increase the number of passengers from the previous year. Meanwhile, the prediction for the least number of passengers is in April 2023, namely 588 people, which is predicted to increase from the previous year. The best model based on the value of the accuracy of the forecasting model is the multiplicative model with a MAPE value of 11.601%. Keywords: Multiplicative model; Tagulandang port; triple exponential smoothing
Image Processing Classification of Rice Leaf Color Images Using the Convolutional Neural Network Method Muhammad Kholilurrahman; Wahyul Amien Syafei; Oky Dwi Nurhayati
Jurnal Ilmiah Sains Volume 23 Nomor 2, Oktober 2023
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/jis.v23i2.50415

Abstract

The agricultural sector is essential to meet the world's food needs, for example, in rice farming in Indonesia, problems that occur in rice plants are usually not only caused by fertilization but also the result of various diseases. The aim of this study  to classify nitrogen fertilizer requirements and plant diseases was made based on leaf color using the Convolutional Neural Network (CNN) method which can be used to increase the accuracy of observations because it is objective. This study uses the Kaggle dataset with a total of 1600 data divided by 4 criteria. The data set was then divided into 70 percent of the training section, 15 percent of the validation section, and 15 percent of the test section, then pre-processed the rice leaf image with color image features and GLCM. The preprocessing results are processed using the CNN method to provide results for detecting plant diseases and the need for appropriate nitrogen fertilization. The calculation of plant diseases using the CNN method offers the highest accuracy of 98.33%.  The highest accuracy for the nitrogen requirement problem was 81.67%, but with a very low precision value of 4.55%. Calculating plant diseases using the CNN method can provide satisfactory results on rice leaf image datasets so that it can be used as a basis for improving seed quality. Keywords: CNN; images of rice leaves; machine learning
Fotodegradasi Rhodamin B Menggunakan Komposit Perak Fosfat- Hidroksiapatit dari Tulang Ikan Cakalang (Katsuwonus pelamis) Lusiana Eka Sari; Audy D. Wuntu; Max R.J. Runtuwene; Lidya Irma Momuat
Jurnal Ilmiah Sains Volume 23 Nomor 2, Oktober 2023
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/jis.v23i2.50469

Abstract

Hydroxyapatite (HAp) treated with silver would produce silver phosphate (Ag3PO4), which is a semiconducting material and can degrade synthetic dyes. This study aimed to synthesize a composite material with the main components of HAp from skipjack (Katsuwonus pelamis) bone and Ag3PO4 used to degrade the synthetic dye Rhodamin B (RB) in aqueous solution. The resulting material was characterized using X-Ray Diffraction (XRD), Scanning Electron Microscopy with Energy-Dispersive X-Ray (SEM-EDX), and Fourier Transform Infrared (FTIR) Spectroscopy. The photodegradation of Rhodamine B was evaluated under visible light irradiation with variations in the number of composites, irradiation intensity, and irradiation time. Characterization results showed the formation of Ag3PO4/HAp composites, and photodegradation tests showed that the higher the amount of photocatalyst used and the higher the light intensity, the more synthetic dyes were degraded. Keywords: Ag3PO4; photodegradation; hydroxyapatite; rhodamine B; skipjack tuna bone
Sunscreen Test of Methanol Extract, N-Hexane, Ethyl Acetate and Methanol-Water Fraction of Artocarpus lanceifolius Roxb. Leaves Based on In Vitro Method Eva Marliana; Novia Rahmawati Isyahro; Nanang Tri Widodo
Jurnal Ilmiah Sains Volume 23 Nomor 2, Oktober 2023
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/jis.v23i2.51543

Abstract

Sunscreen test of  keledang (Artocarpus lanceifolius Roxb.) leaves based on in vitro method was carried out. This research aimed to investigate the property of sunscreen from methanol extract, n-hexane, ethyl acetate and methanol-water fraction of keledang leaves. The methods used include the in vitro methods by using spectrophotometer UV-Vis. Based on results of phytochemical test, it was known that  methanol extract contains flavonoids, phenolics, steroids/triterpenoids. n-Hexane fraction contains steroids/triterpenoids and quinones. Ethyl acetate fraction contains flavonoids, phenolics, steroids/triterpenoids and quinones. Methanol-water fraction contains flavonoids and phenolics. Methanol extract, n-hexane, ethyl acetate and methanol-water fraction also showed sunscreen activity based on the SPF value at a concentration of 25; 50; 100; 150; 200 and 250 mg/L. Crude methanol extract has SPF value respectively were 4.44; 7.36; 15.15; 22.47; 31.25 and 37.31 (minimum-ultra). N-Hexane fraction has SPF value respectively were 1.37; 2.24; 5.07; 7.51; 10.01 and 12.74 (minimum-maximum). Ethyl acetate fraction has SPF value respectively were 3.321; 7.20; 13.03; 19.54; 25.97 and 30.59 (minimum-ultra). Methanol-water fraction has SPF value respectively were 5.24; 10.87; 21.48; 30.89; 36.01 and 38.52 (medium-ultra). The SPF value increases with increasing concentration because the higher the concentration, the more active sunscreen compounds contained in the extract and fraction. In keledang leaves, methanol-water fraction has the highest suncreen activity folowed by methanol extract, ethyl acetate fraction and n-hexane fraction. Keledang leaves have a potency as  sunscreen agent. Keywords: Artocarpus lanceifolius; in vitro; sunscreen

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