cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
Suhartono
Contact Email
suhartono@usk.ac.id
Phone
-
Journal Mail Official
jurnal.natural@fmipa.unsyiah.ac.id
Editorial Address
Block A 2nd Floor FMIPA USK Jl. Tegk. Syech Abdurrauf No. 3, Banda Aceh, 23111, Indonesia
Location
Kab. aceh besar,
Aceh
INDONESIA
Jurnal Natural
Published by Universitas Syiah Kuala
ISSN : 14118513     EISSN : 25414062     DOI : https://doi.org/10.24815/jn
Core Subject : Science, Agriculture,
Agriculture, Biological Sciences & Forestry Astronomy Biochemistry, Genetics & Molecular Biology Chemistry Earth & Planetary Sciences Energy Immunology & microbiology Neuroscience Physics
Jurnal Natural (JN) aims to publish original research results and reviews on sciences and mathematics. Jurnal Natural (JN) encompasses a broad range of research topics in chemistry, pharmacy, biology, physics, mathematics, statistics, informatic and electronic.
Arjuna Subject : Matematika - Matematika (Lain-Lain)
Articles 457 Documents
 21   22   23   24   25 
Application of Poisson and negative binomials models to estimate the frequency of insurance claims RINI OKTAVIA; RAHMA ZUHRA; HAFNANI HAFNANI; NURMAULIDAR NURMAULIDAR; INTAN SYAHRINI
Jurnal Natural Volume 23 Number 1, February 2023
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v23i1.26623

Abstract

Generalized Linear Models (GLMs) are a modeling approach that allows the modeling of nonlinear behaviors and non-Gaussian distributions of residues. This approach is very useful for general insurance analysis, where the frequency of claims and the amount of claims distributions are usually non-Gaussian. In this article, the application of Poisson and Negative Binomial models to estimate the frequency of claims of auto insurance is discussed. The accuracy of the models was compared to choose the best model for determining pure insurance premiums using R software. The data used are a secondary dataset which is the motor vehicle insurance dataset from Sweden named dataOhlsson and the motor vehicle dataset from Australia named ausprivauto0405. The results of the exploration of the GLMs model are that Poisson's GLM and Negative Binomial models both are suitable models for estimating the number of claims for the dataOhlsson dataset. Both models have relatively similar parameter estimates, as well as the AIC and BIC values for the dataOhlsson dataset, however, both models are not suitable for estimating the number of claims for the ausprivauto0405 dataset. More investigation using different models is needed to ensure which model is more appropriate for estimating the frequency of insurance claims.
Thermal and physical properties of CNF/glutaraldehyde-gelatin-based hydrogel ROSLIANA LUBIS; SRI WAHYUNA SARAGIH; WARDATUL HUSNA IRHAM; AJMAIN AJMAIN; SAISA SAISA
Jurnal Natural Volume 23 Number 1, February 2023
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v23i1.29935

Abstract

The use of hydrogel as a wound dressing material is currently being massively developed. In addition to functioning to protect wounds, the use of hydrogel can also provide moisture in a measured manner and can be used as a drug delivery medium. In this study, hydrogel based on CNF and glutaraldehyde crosslinking agent and addition of gelatin were developed with various compositions 0.25; 0.5; 0.75 g to increase the ability of CNF and hydrogel to absorb water so that it is good to be applied as a wound dressing. The composting of the three materials aims to obtain a hydrogel with good thermal and physical properties. Based on physical character for a good ratio of swelling (666,62%) and degree of cross-linking (94%) on the hydrogel with a composition variation of 0.5 g of CNF addition. For the thermal stability of hydrogel var 2, TMax 591oC provides better thermal stability than var 1 and var 3. The morphology of hydrogel shows very small and evenly distributed pores on the surface which can absorb more water.
Isolation of active compound as anti acne from ethanol extract Artocarpus camansi leaves AZALIA IZDHIHAR AZWAR; MUHAMMAD BAHI; ROSNANI NASUTION; NURDIN NURDIN; MARIANNE MARIANNE
Jurnal Natural Volume 23 Number 1, February 2023
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v23i1.27036

Abstract

Acne vulgaris or acne is a chronic inflammatory skin disease in adolescents and adults affecting one self-confidence. The result of the research shows the ethanol extract, subfraction, pure isolate, and gel extract of Artocarpus camansi are active in inhibiting the growth of Propionibacterium acnes. The ethanol extract with the highest inhibition zone was at the concentration of 0.5 and 2% with 9.1±0.62 mm and 8.5±0.7 mm with the activity of 47.07% and 43% respectively (in comparison with the chloramphenicol 30 μg 19.33±0.47mm). The gel extract had the highest activity at 2%, with an inhibition zone of 8±0.50 mm and the activity of 43.97%. Anti-acne activity for all subfractions had an activity of 32.5-33.3% while the pure isolate was at 42.10 - 45.63%. Physical properties of the gel extract were evaluated for four weeks by examining the pH test obtained with a range of 5.8-6.7, viscosity in the range of 18460-19668 cP, spreadability in the range of 5.45-7.20 cm, adhesion observation above 4 seconds, and homogeneity in a concentration of 0.5-7.5%. The pure isolate has a melting point of 147 ℃, presumed to be γ-sitosterol and appropriate with the screening phytochemicals results with the presence of steroid.
Antiseptic activity assay of ethanolic extract of Aceh’s rambutan rind (Nephelium lappaceum L.) against Staphylococcus aureus and its formulation as hand sanitizer gel IRMA SARI; MEUTIA FARADILLA; RISKA ANANDA PUTRI
Jurnal Natural Volume 23 Number 1, February 2023
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v23i1.20412

Abstract

The hands are one of the most susceptible parts of the human body to bacterial infection. One way to maintain health is to maintain hand hygiene. Ethanolic rambutan rind extract from Aceh province has been studied in order to determine if it can inhibit bacterial growth. This research was conducted to determine the antiseptic activity of the ethanol extract of rambutan rind against Stahpylococcus aureus by determining the phenol coefficient and determining whether the ethanolic extract of Aceh’s rambutan rind can be formulated into a hand sanitizer gel. Antiseptic activity testing was performed using the Rideal-Walker method which was carried out in 5 dilutions (1:100, 1:150, 1:200, 1:250 and 1:300). The absorbance measurement showed that the extract could act as an antiseptic, at a concentration of 1% and at a dilution of 1:200 which has phenol coefficient of 1.67. The ethanolic extract of Aceh’s rambutan rind can be formulated in the form of a hand sanitizer gel using 1% Carbopol as gelling agent. The results showed that the gel was brown with a distinctive menthol odor and changed into a dark brown color after a cycling test. The evaluation results of all formulas appropriated the requirements except for adhesion parameter. The results of the irritation test showed that the volunteers did not experience any signs of irritation. The results of the preference test showed that the respondents liked the shape and aroma parameters but not the color parameter.
The effect of brewing time herbal tea from mother-in-law’s tongue leaves (Sansevieria trifasciata Prain) on total phenol, total flavonoid, and antioxidant activity MAYA PRATIWI HUTABARAT; ZULKIFLI LUBIS; JANSEN SILALAHI
Jurnal Natural Volume 23 Number 1, February 2023
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v23i1.28329

Abstract

Indonesia is a tropical country known for its biodiversity, one of which is the mother-in-law’s tongue (Sansevieria trifasciata Prain). Mother-in-law’s tongue leaves extract contains bioactive compounds, such as triterpenoids, steroids, and flavonoids and tradionally used especially as antidiabetics. The phenolic and flavonoid compounds in mother-in-law’s tongue are potential antioxidants, and usually processed into herbal tea. This research aimed to determine the effect of duration brewing time herbal tea from mother-in-law’s tongue leaves (Sansevieria trifasciata Prain) on total phenol, total flavonoid, and antioxidant activity. This study using Completely Randomized Designed (CRD) with 5 treatments (different brewing time that were 1, 3, 6, 9, 12 minutes) and 3 replications. The result showed that brewing time had a significant effect on total phenol, total flavonoid, and antioxidant activity.  The optimum of brewing time herbal tea from mother-in-law’s tongue leaves is 6 minutes.
Study on the performance of Robust LASSO in determining important variables data with outliers ROCHYATI ROCHYATI; KUSMAN SADIK; BAGUS SARTONO; EVITA PURNANINGRUM
Jurnal Natural Volume 23 Number 1, February 2023
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v23i1.26279

Abstract

A variable selection method is required to deal with regression models with many variables, and LASSO has been the most widely used methodology.  However, as several authors have noted, LASSO is sensitive to outliers in the data.  For this reason, the Robust-LASSO approach was introduced by applying some weighting schemes for each sample in the data.  This research presented a comparative study of the three weighting schemes in Robust LASSO, namely Huber-LASSO, Tukey-LASSO, and Welsch-LASSO.  The study did a rich simulation containing many scenarios with various characteristics on the covariance structures of the explanatory variable, the types of outliers, the number of outliers, the location of active variables, and the number of variables.  The study then found that Tukey-LASSO outperformed Huber-LASSO and Welsch-LASSO in identifying significant variables.  The Robust LASSO performance generally decreased as the covariances among explanatory variables increased and the data dimension increased.  Exploration of sembung leaf extract data shows that the data is high dimensional data which contains outliers of about 14,28% on the response variable and about 25,71% on the explanatory variables.  Based on the research, the number of variables selected using the Tukey-LASSO method was nine compounds, Huber-LASSO and Welsch-LASSO were eight compounds, and LASSO 13 compounds.  The Tukey-LASSO prediction accuracy is superior to the other three methods.
Performance of copula and nested error regression models in estimating per capita expenditure of sub-district in Pidie Regency NUR HASANAH; KHAIRIL ANWAR NOTODIPUTRO; BAGUS SARTONO
Jurnal Natural Volume 23 Number 2, June 2023
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v23i2.31095

Abstract

In unit-level small area estimation (SAE), the commonly used nested error regression (NER) model assumes normality which is not always the case. To handle non-normal data, researchers in statistics have developed a novel approach using exchangeable and extendible copula called the multivariate exchangeable copula (MEC) model. This study compares the performance of parametric MEC and NER models in estimating the sub-district average of per capita expenditure (PCE) in Pidie Regency, Aceh Province. This study presents PCE, which has a skewed distribution of the three-parameter skew-normal. The parametric MEC model uses a Gaussian copula from the Elliptical family and an empirical best unbiased prediction (EBUP) estimator. Meanwhile, the NER model uses an empirical best linear unbiased prediction (EBLUP) estimator. The results reveal that at a 95% confidence level, the parametric MEC model outperforms the NER model with a smaller root of mean squared error (RMSE) and provides a more precise estimate of the sub-district average of PCE. This study highlights the importance of considering the parametric MEC model as an alternative method for skewed data in unit-level SAE. The results of this study have the potential to support the achievement of Goal 1 (to end poverty) and Goal 10 (to reduce inequality) of the sustainable development goals (SDGs) by providing average PCE estimates at the sub-district level.
Composition and similarity of vegetation types in the Mount Seulawah Agam geothermal area, Aceh Besar District DAHLAN DAHLAN; MUHAMMAD DOUDI; SAIDA RASNOVI; DALIL SUTEKAD; MUSLICH HIDAYAT
Jurnal Natural Volume 23 Number 2, June 2023
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v23i2.31989

Abstract

The Mount Seulawah Agam area is an active volcanic area that has an impact on the emergence of symptoms of volcanism. Such environmental conditions will cause the vegetation that grows in the area to be unique and not commonly found in other areas. Apart from that, the area is still relatively natural and has not experienced much disturbance by human activities. This study aims to determine the composition and similarity of vegetation types in the geothermal area of Mount Seulawah Agam, Aceh Besar District. Data collection in the field was carried out using the multiple square method which was placed in a stratified sampling based on the specified soil temperature zone. Each zone was laid out in 4 square plots in a systematic random manner. Each plant contained in the observation plot is recorded in the name of the plant species using a flora identification book, and the number of individuals of each type is recorded. Data analysis was carried out using the Important Value Index analysis, and the Sorenson Similarity Index. The results showed that there were 65 species from 611 individual plants identified starting from the growth rate of seedlings, sapling, poles, and trees. The similarity index of plant species at each growth stage in the Seulawah Agam geothermal area, Aceh Besar District generally has different species similarity in each observation zone, that is, the average is below 50%. This condition indicates that there are significant differences in plant structure at various growth rates in each zone
The Classification of “Program Sembako” recipients in Payobasung West Sumatra based on the K-nearest neighbors classifier HAZMIRA YOZZA; NINDI MAULA AZIZAH; LYRA YULIANTI; IZZATI RAHMI
Jurnal Natural Volume 23 Number 2, June 2023
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v23i2.29738

Abstract

The "Sembako Program" is a program carried out by the Indonesian government to improve the welfare of low-income communities. The purposes of this study are: (a) to determine the classification of households that deserve to receive basic-food assistance in Koto Panjang Payobasung, West Sumatra, using the KNN classifier and (b) to determine the optimal number of nearest neighbors used in the classification process. The measure of proximity between objects used is the Gower dissimilarity coefficient. This research used primary data consisting of 175 households collected purposively in a survey conducted on all households in Payobasung.  The optimal K value is determined by implementing a 5-fold cross-validation procedure. The result showed that the best classification process is when K = 3 nearest neighbors are used since it produces the highest accuracy coefficient and Mattews correlation coefficient (MCC). Therefore, for further work, in deciding the eligibility of a household to receive the Sembako Program in Payobasung, KNN can be used by considering its 3 nearest neighbors
Analysis of protease activity of melinjo (Gnetum gnemon L.) skin on the tenderness of buffalo meat FAISAL ABDURRAHMAN; OTHMAN OMAR; ISWADI ISWADI
Jurnal Natural Volume 23 Number 2, June 2023
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v23i2.28624

Abstract

To enhance the tenderness of meat, it can be accomplished physically or chemically. In chemical way, the process can be accomplished using protease enzymes that can be obtained from fruit, the higher the protease enzyme activity, the softer the meat. In this experiment, the extract and juice of melinjo skin (Gnetum gnemon L) was used to examine the protease enzyme activity. Papaya (Carica papaya) and pineapple (Ananas comosus) were used as a comparison. The research was conducted to understand the influence of incubation time (t) and incubation temperature (To) towards the optimum activity characteristic of protease enzyme on the juice and the extract of melinjo skin, papaya and pineapple. The incubation time of juice and extract was from 0 to 90 minutes with incubation temperature of 37 C and incubation time at 20 minutes with incubation temperature range from 20 to 80C. The protease enzyme activity of juice and extract expand significantly (p0.05) in conjunction with the increase of incubation time and temperature. The research results revealed that the maximum activity of protease enzyme detected at incubation time of 90 minutes for melinjo juice and pineapple skin, and 10 minutes for papaya. The optimum incubation temperature of melinjo skin at 70 C, papaya at 60C and pineapple juice at 60C. Meanwhile, the maximum activity of protease enzyme from melinjo extract identified in the incubation time at 80 minutes, papaya at 90 minutes and pineapple 60 minutes, whereas the incubation temperature of melinjo skin juice at 60 C, papaya at 80  C and pineapple at 30C.

Page 23 of 46 | Total Record : 457

 21   22   23   24   25 

Filter by Year

2010 2025


Reset
Filter By Issues
All Issue Volume 25 Number 3, October 2025 Volume 25 Number 2, June 2025 Volume 25 Number 1, February 2025 Volume 24 Number 3, October 2024 Volume 24 Number 2, June 2024 Volume 24 Number 1, February 2024 Volume 23 Number 3, October 2023 Volume 23 Number 2, June 2023 Volume 23 Number 1, February 2023 Volume 22 Number 3, October 2022 Volume 22 Number 2, June 2022 Volume 22 Number 1, February 2022 Volume 21 Number 3, October 2021 Volume 21 Number 2, June 2021 Volume 21 Number 1, February 2021 Volume 20 Number 3, October 2020 Volume 20 Number 2, June 2020 Volume 20 Number 1, February 2020 Volume 19 Number 3, October 2019 Volume 19 Number 2, June 2019 Volume 19, Number 1, February 2019 Volume 18, Number 3, October 2018 Volume 18, Number 2, June 2018 Volume 18, Number 1, February 2018 Volume 17, Number 2, September 2017 Volume 17, Number 1, March 2017 Volume 16, Number 2, September 2016 Volume 16, Number 1, March 2016 Volume 15, Number 2, September 2015 Volume 15, Number 1, March 2015 Volume 14, Number 2, September 2014 Volume 14, Number 1, March 2014 Volume 13, Number 2, September 2013 Volume 13, Number 1, March 2013 Volume 12, Number 2, September 2012 Volume 12, Number 1, March 2012 Volume 11, Number 2, September 2011 Template More Issue