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
 29   30   31   32   33 
The effect of organic fertilizers on the leaf morphology and stomatal density of Pogostemon cablin Benth MEUTIA ZAHARA; SUWARNIATI SUWARNIATI; QURRATU AINI; MUSLIM MUSLIM
Jurnal Natural Volume 21 Number 2, June 2021
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v21i2.20989

Abstract

Pogostemon cablin Benth is one of the most important crops grown in Indonesia, especially in Aceh province. It is well known as Patchouli belongs to Lamiaceae family and shows a great demand for perfume, luxury products, food and beverage industry. This study conducted to determine the effect of organic fertilizers application on the leaf morphology and stomatal density on the Pogostemon cablin Benth. The seedlings were transplanted for three months on the soil mixed either with manure or compost. The results obtained that was no significant different in affecting the leaf morphology of Pogostemon cablin Benth. The treatment with manure application showed the highest leaf length (15.23 cm) and the highest leaf width (10.5 cm), the leaf color is green. While the stomatal density obtained the significant difference among the treatments, the highest stomatal density in both side of the leaf surface showed in the application of manure, 663.5 mm-2 for adaxial part and 486.38 mm-2 for abaxial part. Stomatal type is anisocytic and on the leaf surface was found glandular and non-glandular trichomes.
ANALYSIS OF MINERALS IN CEMPAKA-MADU GEMSTONE FROM ACEH INDONESIA BY USING XRF Ismail .; Akmal Nizar; Mursal .
Jurnal Natural Volume 18, Number 1, February 2018
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v18i1.9802

Abstract

Abstract. Cempaka-madu is a local name for one kind of gemstone from Aceh province in Indonesia. It is so attractive and its color is dark-orange. We have utilized X-Ray Florescent (XRF) to study these cempaka-madu gemstones from Aceh Tengah and Nagan Raya districts in Aceh province. Our results show that the cempaka-madu gemstone from Nagan Raya district contains 84.90% of SiO2, 8.89% of NiO, 5.47% of Fe2O3, and 0.6% of CaO. The mineral contains in cempaka-madu gemstone from Aceh Tengah district is about the same as those from Nagan Raya district. It is found that the oxide compounds contained in the cempaka-madu gemstone is significantly different than that in jadeite, nephrite-actinolite, nephrite-tremolite, serpentine-clinochrysotile, serpentine-antigoride, and vesuvianite. Consequently, we conclude that the cempaka-madu gemstone from Aceh Indonesia cannot be categorized as jade. Keywords: cempaka-madu gemstone, jade, jadeite, nephrite, serpentine, vesuvianite
SISTEM KENDALI PROPORSIONAL, INTEGRAL, DAN DERIVATIF (PID) PADA PERSAMAAN PANAS Muhammad Ikhwan; Said Munzir; Nurmaulidar Nurmaulidar
Jurnal Natural Volume 16, Number 2, September 2016
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v16i2.4918

Abstract

This research showed the application of Proportional, Integral, and Derivative (PID) control system on heat equations that has non-integer ordered solutions on Laplace domain. Zala tuning method and Ziegler-Nichols method; which is ultimate cycle and process reaction method, are used to determine the value of Kp, Ti and Td as constants in PID to maintain the temperature of 1oC on the position of x = 3 m from the heat source with k = 0,042 m2s-1 diffusivity. Based on the results, there were ten systems that were closest in the desired criteria. With regards to overshoot and the time taken to reach the stable position, therefore the ten systems that are produced have not many differences in strengths and weaknesses. 
Optimization of fuzzy entropy on solar panel’s motor MUHAMMAD IKHWAN; MARWAN RAMLI; MARDLIJAH MARDLIJAH
Jurnal Natural Volume 22 Number 1, February 2022
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v22i1.23187

Abstract

Renewable energy has been in great demand by the public, even some countries have set regulations for substitution and transition from fossil energy to renewable energy. This study aims to modify the fuzzy control system with a metaheuristic method, namely fuzzy entropy. The entropy value of the fuzzy set in the previous stage becomes the basis for calculating the foot of uncertainty in the new fuzzy set. This process makes the entropy method parallel to other optimization methods that have been carried out on fuzzy control systems. The results obtained indicate that the modified fuzzy control system successfully controls the angle and angular velocity of the solar panel. The error value shown is very small and the time to reach stability is below 5 s. This is a rapid development of several previous studies. The modified system has no overshoot and steady state error below 1%. Based on these results, entropy research can be developed again by changing the fuzzy set to a more complex form.
CHARACTERISTICS OF NATURAL MAGNETITE (Fe3O4) FROM BEACH SAND AS CATALYST APPLICATION IN MATERIALS INDUSTRY Maulinda Maulinda; Ikramullah Zein; Zulkarnain Jalil
Jurnal Natural Volume 19, Number 1, February 2019
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v19i1.12475

Abstract

An identification of magnetite nanoparticles synthesized from natural iron sand using co-precipitation method has been conducted. The treatment was undertaken at room temperature and the heating used a pair of acid-base compounds, namely HCL as a solvent and NH4OH as a precipitate. Crystal structures, percentages of elements, particle sizes and magnetic characteristics of the materials were characterized by testing XRF, XRD and Permagraph. The results were then compared with the commercial material purchased from Aldrich (with 97% purity). From the results, it was found that the percentage value of the purity of Fe3O4 derived from natural sand before the extraction was 81.42%, and after the extraction it increased to 86.73%. Furthermore, the saturation magnetization (Ms) value for Fe3O4 ferrite from iron sand was 0.29 T, the residual magnetization or Remanen (Br) was 0.081 T, and Coersivity (Hc) was 1.82 kA/m.
Diet of White-throated Kingfisher (Halcyon smyrnensis [Linnaeus, 1758]: Alcedinidae: Coraciiformes) inferred from pictorial postings in social media JANRA, MUHAMMAD N.; PUTRI, RINA A.; HERWINA, HENNY
Jurnal Natural Volume 24 Number 1, February 2024
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v24i1.31465

Abstract

White-throated kingfisher Halcyon smyrnensis (family Alcedinidae, order Coraciiformes) is known to distribute widely in Asia, including Sinai Peninsula, South Asia, China, until Southeast Asia. As each population has become resident to their respective range, it has adapted to its environment which effect on diet they eat. Recall that the wide distribution of this kingfisher, it is difficult to do field survey to observe the range of its dietary. This study aims to do an inventory on the diet of white-throated kingfisher by using social media as survey platform. Instagram and Facebook were surveyed by making inquiries using keywords such as white-throated kingfisher, Halcyon smyrnensis, and other terms related to this kingfisher species. The query specifically sought pictorial postings instead of non-pictorial ones, in order to analyze preys classification. More than 1,200 posts were retrieved from the two social media, yet only 89 posts counted as they showed predation activities by this species. Identification on the preys signifies that they consist of arthropods (27.0%), fishes (19.1%), amphibians (13.5%), reptiles (20.2%), other birds (6.7%), mammal (1.1%) and unknown prey items (12.4%). Including into these preys were monitor lizard, munia, locusts, crickets, beetles, cockroaches, and snails which may become pests in agricultural area. The wide array of diet consumed by white-throated kingfisher not only proves its opportunistic nature in preying food items, nevertheless it also provides opportunity to use this bird as natural biological control in agricultural system.
Application of gravity method in cultural harritage Cot Sidi Abdullah Site, Samudera Pasai, North Aceh NOVIA PURNAMA SARI; TOMI AFRIZAL; FAISAL ABDULLAH; NAZLI ISMAIL
Jurnal Natural Volume 20 Number 3, October 2020
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v20i3.16920

Abstract

The gravity method was applied to the cultural heritage site of Cot Sidi Abdullah in Kuta Krueng Village, Samudera Pasai District, North Aceh Regency for mapping and reconstruction structure of the cultural heritage site and distribution of artifact objects buried in the subsurface. Data measurement was carried out in a grid with 2 meters spacing between the points to cover all area of the cultural heritage site. The model of gravity anomaly distribution from the vertical derivative results shows a square pattern of anomaly gravity surrounding the measurement areas. This anomaly pattern is thought as a response from the remaining walls of the site structure which are buried in the subsurface with anomalous values between 0.02 mGal/m - 0.08 mGal/m.  The estimation of the walls of the archaeological site from the anomalous response to this gravity value is proved by the excavation results in the southern part of the study area.  While the minimum value of the vertical derivative filter (-0.06 mGal/m to - 0.01 mGal/m) is the response from the area around the archaeological site.  The reconstruction results of the site based on the estimation of the walls with a length of ± 45 meters and a width of ± 40 meters.
SEMI-IMPLICIT NUMERICAL SCHEMA IN SHALLOW WATER EQUATION safwandi safwandi; Syamsul Rizal; Tarmizi Tarmizi
Jurnal Natural Volume 17, Number 2, September 2017
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v17i2.7998

Abstract

Abstract. A two-dimensional shallow water equation integrated on depth water based on finite differential methods. Numerical solutions with different methods consist of explicit, implicit and semi-implicit schemes. Different methods of shallow water equations expressed in numerical schemes. For bottom-friction is described in semi-implicitly. This scheme will be more flexible for initial values and boundary conditions when compared to the explicit schemes.  Keywords: 2D numerical models, shallow water equations, explicit and semi-implicit schema.Reference Hassan, H. S., Ramadan, K. T., Hanna, S. N. 2010. Numerical Solution of the Rotating Shallow Water Flows with Topography Using the Fractional Steps Method, Scie.Res,App.Math. (1):104-117. Omer, S, Kursat, K. 2011. High-Order Accurate Spectral Difference Method For Shallow Water Equations. IJRRAS6. Vol. 6. No. 1. Kampf, J. 2009. Ocean Modelling for Beginners. Springer Heidelberg Dordrecht. London, New York. Wang, Z. L., Geng, Y. F. 2013. Two-Dimensional Shallow Water Equations with Porosity and Their Numerical scheme on Unstructured Grids. J. Water Science and Engineering. Vol. 6, No. 1, 91-105. Saiduzzaman, Sobuj. 2013. Comparison of Numerical Schemes for Shallow Water Equation. Global J. of Sci. Fron. Res. Math. and Dec. Sci. Vol. 13 (4). Sari, C. I., Surbakti, H., Fauziyah., Pola Sebaran Salinatas dengan Model Numerik Dua Dimensi di Muara Sungai Musi. Maspari J. Vol. 5 (2): 104-110. Bunya, B., Westerink, J. J. dan Shinobu, Y. 2004. Discontinuous Boundary Implementation for the Shallow Water Equations. Int. J. Numer. Meth. Fluids 2005 (47): 1451–1468. 
THE EFFECT OF MAGNETITE (Fe3O4)CATALYST FROM IRON SANDS ON DESORPTION TEMPERATURE OF MgH2 HYDROGEN STORAGE MATERIAL Maulinda Maulinda; zulkarnain Jalil; Adi Rahwanto
Jurnal Natural Volume 16, Number 1, March 2016
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v16i1.4362

Abstract

One of the future technologies for a safe hydrogen storage media is  metal hydrides. Currently, Mg-based metal hydride has a safety factor and efficient for vehicle applications. However, the thermodynamic properties of magnesium hydride (MgH2) found a relatively high temperature. High desorption temperatures caused MgH2 high thermodynamic stability resulting desorption enthalpy is also high. In this study, natural mineral (iron ore) has been extracted from iron sand into powder of magnetite (Fe3O4) and used as a catalyst in an effort to improve the desorption properties of MgH2. Magnetie has been successfully extracted from iron sand using precipitation method with a purity of 85 % , where the purity of the iron sand before extracted was 81%. Then, MgH2-Fe3O4 was milling using mechanical alloying method with a variety of catalysts and milling time. The observation by XRD showed the material was reduced to nanocrystalline scale. MgH2 phase appears as the main phase. DSC test results showed with the addition of Fe3O4, the desorption temperature can be reduced up to 366oC, compared to pure pure MgH2 reached by 409o C. Furthermore, based on gravimetric test, the hydrogen release occurs at a temperature of 388o C, weight loss  of 0.66 mg during 16 minutes.
Predicting life expectancy of lung cancer patients after thoracic surgery using SMOTE and machine learning approaches SELLY ANASTASSIA AMELLIA KHARIS; ARMAN HAQQI ANNA ZILI
Jurnal Natural Volume 23 Number 3, October 2023
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v23i3.29144

Abstract

. Lung cancer is a life-threatening condition characterized by the uncontrolled growth and spread of abnormal cells in the lungs. Thoracic surgery is a commonly employed diagnostic and treatment procedure for lung cancer. The objective of this study is to utilize machine learning techniques to predict the life expectancy of lung cancer patients one year after thoraric surgery. The study utilizes the Thoraric  Surgery Data Set, consisting of 454 data, with 385 data representing surviving patients and 69 data representing patients who passed away. Due to an imbalance in the data, the Synthetic Minority Oversampling Technique (SMOTE) process is applied to balance the dataset. Multiple machine learning algorithms, including Random Forest (RF), K-Nearest Neighbor (KNN), and Support Vector Machine (SVM), are employed for prediction. Validation is performed using 5-fold cross validation, repeated three times. The results indicate that the KNN model achieves the highest mean accuracy of 84.80% before the SMOTE process, although all models exhibit a low mean F1-score. Following the SMOTE process, the RF model attains  the highest mean accuracy of 79.52%, while the KNN model demonstrates  the highest mean F1-score of 26.54%. This research contributes valuable insights to clinicians in making informed decisions and improving patient outcomes.

Page 31 of 46 | Total Record : 457

 29   30   31   32   33 

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