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Abdul Muis Muslimin
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Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Papua Jalan Gunung Salju Amban, Manokwari 98314
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Jurnal Natural
Published by Universitas Papua
ISSN : 14121328     EISSN : 2746427X     DOI : -
Core Subject : Science, Education, Agriculture,
Agriculture, Biological Sciences & Forestry Chemistry Mathematics Physics
Jurnal Natural merupakan jurnal ilmu-ilmu matematika dan pengetahuan alam (basic science) untuk bidang: matematika, kimia, statistika, biologi, dan fisika termasuk ilmu terapan yang terkait seperti bioteknologi, kimia pangan, keanekaragaman hayati, dan lain-lain.
Arjuna Subject : Umum - Umum
Articles 160 Documents
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MODEL PREDIKSI SUHU PERMUKAAN LAUT PERAIRAN KO-TA MANOKWARI KABUPATEN MANOKWARI MENGGUNAKAN DEEP NEURAL NETWORKS Elohansen Padang
Jurnal Natural Vol. 19 No. 1 (2023): Jurnal Natural
Publisher : FMIPA Universitas Papua

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30862/jn.v19i1.232

Abstract

In this research, we have been done developed a prediction model for Sea Surface Temperature (SST) in the sea of Manokwari City, Manokwari Regency using deep learning models, especially the Deep Neural Networks (DNN) model. The SST data used is ERA5 reanalysis data provided by the European Center for Medium-Range Weather Forecast (ECMWF) from 2000-2021 (8233 daily data). The SST data is divided into two parts, namely training and testing data with a proportion of 90% and 10%, respectively. The DNN model developed uses the hyperparameter optimizer adam, the ReLu activation function, the learning rate is 0.01, the Batch size is 30, the number of inputs is 10, the number of epochs is 100 and is equipped with early stops. Meanwhile, the number of hidden layers varied between 1 until 4. Likewise, the number of neurons in each hidden layer varies from 8, 16, 32, 64, or 128 neurons. Based on the test results, the DNN model with 2 hidden layers and 32 neurons per hidden layer gives more accurate results than the other models, with RMSE, MAE, and R2 values respectively 0.121; 0.015; and 0.935. Therefore, this DNN model can be recommended as a model to predict SST in sea of Manokwari City.
Penurunan Persamaan Gelombang Air Dangkal (Shallow Water Wave) Menggunakan Hukum Kedua Newton Inayatul Farach Ardianty; Tri Widjajanti Widjajanti; Rium Hilum
Jurnal Natural Vol. 19 No. 1 (2023): Jurnal Natural
Publisher : FMIPA Universitas Papua

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30862/jn.v19i1.206

Abstract

These waves occur when the surface of the water is disturbed by wind, gravity, earthquakes, or landslides on the seabed. Shallow water waves can be modelled or expressed in mathematical language, namely the shallow water wave equation which is a partial differential equation. The shallow water wave equation is a partial differential equation that describes the fluid flow problem. A system is considered shallow water if the depth of the fluid is much less than its wavelength. Shallow water waves are a phenomenon of classical mechanics which can be described by three simple laws called Newton’s laws of motion. The stages in the research include identifying problems, making assumptions, and forming shallow water wave equations using Newton’s Second Law and the law of conservation of mass. The form of the two-dimensional shallow water wave equation is u_t+〖uu〗_x=-gh_x (x,t). and h_t=-[u(D+h)]_x.
EFEKTIVITAS METODE SAND FILTER DALAM MENURUNKAN TINGKAT KEKERUHAN DAN KADAR E.COLI PADA AIR SUMUR Bertha Mangallo; Reynom Alfontus; Agnes Dyah Novitasari
Jurnal Natural Vol. 19 No. 1 (2023): Jurnal Natural
Publisher : FMIPA Universitas Papua

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30862/jn.v19i1.210

Abstract

This study aims to determine the effectiveness of the sand filter method in reducing turbidity and e.coli levels in dug well water. The research method involved preparing filter media consisting of sand and beach pebbles, charcoal from coconut shells, pottery made from clay, and palm fiber. Water treatment is carried out using a filtration column containing filter media. The characteristics of dug well water before processing showed a turbidity level of 6.5 NTU and levels of e.coli ≥1898 CFU/100 mL. The results of the analysis of the quality of processed water using the sand filter method show that the effectiveness of the sand filter method in reducing turbidity levels reaches 100% while reducing e.coli levels reaches 95%.
INVERSI DATA VERTICAL ELECTRICAL SOUNDING (VES) KONFIGURASI SCHLUMBERGER DI KAMPUNG NAMBON KABUPATEN JAYAPURA MENGGUKAN METODE FIXED-WIDTH THICKNESS DAN METROPOLIS SIMULATED ANNEALING Anike Bowaire; Zakaria Victor Kareth
Jurnal Natural Vol. 19 No. 1 (2023): Jurnal Natural
Publisher : FMIPA Universitas Papua

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30862/jn.v19i1.215

Abstract

A Research of inversion of Vertical Electrical Sounding (VES) data of Schlumberger configuration using combination of Simulated Annealing (SA) dan Fixed-Width Thickness methods has been carried out. The fixed-width thickness method was used to objectively determine the number of subsurface layers. The SA method was used because it is stable and the initial model does not have to be at proximity of the actual solution. The inversion results on synthetic data of 3 and 4 layers show a good fit between the sintetik data and inverted model. In addition to the number of layers, the fixed-width thickness method also provides information on the range of depth and resistivity values for each layer whit can be used as input for inversion. The inversion results on synthetic data containing 20% noise indicating that the model and data have a good fit. The level of fit of the method depends on the number of model parameters and the error tolerance. The inversion results on field data in Nambon village, Jayapura district, show that there are 5 subsurface layers. The geological interpretation of these five layers is that the first layer is the top soil layer which is weathered limestone, clay and sand. The second, fourth and fifth layers are limestone of the Jayapura formation (Qpj) with a resistivity range between 923 – 5881 Ωm. The third layer is karst, which may contain groundwater, formed in the limestone of the Jayapura formation.
PENGARUH PENAMBAHAN PEMLASTIS GLISEROL DAN MINYAK BUAH MERAH (Pandanus conoideus) TERHADAP KUAT TARIK DAN ELONGASI BIOPLASTIK BERBAHAN PATI SAGU (Metroxylon sago)-KITOSAN Agnes Dyah Novitasari Lestari
Jurnal Natural Vol. 19 No. 1 (2023): Jurnal Natural
Publisher : FMIPA Universitas Papua

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30862/jn.v19i1.242

Abstract

The need for plastic will increase along with technological and industrial developments, thereby increasing the amount of plastic waste. Oil and gas based plastics are not biodegradable. One way to limit the amount of plastic waste is to use biodegradable plastics, also known as bioplastics. In this study, the bioplastic material used was sago starch from Papua combined with chitosan with the addition of glycerol plasticizers and red fruit (Pandanus conoideus) oil. The use of red fruit oil, apart from being a plasticizer, is also intended to provide antioxidant properties to the resulting bioplastics. The variation in the weight ratio of sago starch: chitosan used is 4:1 and 1:1. The volume of glycerol and red fruit oil added was equal, namely 2.5 mL. After bioplastics have been synthesized, tensile strength and elongation tests are carried out. The results showed that the tensile strength and elongation were greatly influenced by the type of plasticizer, both in sago starch:chitosan ratios of 1:1 and 1:4. The addition of red fruit oil significantly reduced the tensile strength, both in the sago starch:chitosan ratio of 1:1 and 1:4, but increased the elongation in the sago starch:chitosan ratio of 1:4. This indicates that red fruit oil can be used as a plasticiser candidate in bioplastics as antioxidant packaging.
Potensi Usaha Budidaya Tanaman Wortel (Daucus carota L.) Di Rurukan Kota Tomohon Mogea, Rinondom AR; Vanny H Siwi, Vanny H Siwi; mogea, rina
Jurnal Natural Vol. 19 No. 2 (2023): Jurnal Natural
Publisher : FMIPA Universitas Papua

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30862/jn.v19i2.216

Abstract

Carrot business development provides a source of income to meet the needs of farming families and also to continue their farming activities. This study aims to analyze profits, Break Event Point values and the feasibility of carrot farming in Rurukan Village. he data collection method uses a survey method. The data used includes primary and secondary data taken by interview, observation and recording techniques. Determination of carrot farmer samples by purposive sampling with the consideration that farmers obtain credit from the banking sector with an average land area of 1 ha. The data analysis used is profit analysis namely Revenue/Cost (R/C), Break Even Point (BEP) and Internal Rate of Return (IRR). The results showed that the profit of each respondent in the first harvest season averaged IDR 1,210,745 and the profit of farmers in the second season was IDR 11,402,917. The first season's R/C value was 164 and the second season's R/C value was 300. The first season's BEP value was Rp. 331 and for the second harvest was 157. The BEP value of production volume for the first season was 21328 kg and for the second harvest was 12100 kg. The NPV value is IDR 266,090,644 and the IRR value is 60%. This value means that the carrot cultivation business in Rurukan Village is profitable and feasible to develop.
TINGKAT RISIKO GEMPA BUMI DI KABUPATEN NABIRE BERDASARKAN PERHITUNGAN NILAI PERCEPATAN TANAH MAKSIMUM MENGGUNAKAN METODE DONOVAN Ika Widi Astuti; Ipa, Sangaji Hasmi Maharani; Indra Birawaputra; Erari, Ishak Semuel
Jurnal Natural Vol. 19 No. 2 (2023): Jurnal Natural
Publisher : FMIPA Universitas Papua

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30862/jn.v19i2.239

Abstract

Kota Nabire merupakan salah satu kota di Papua yang mempunyai tingkat resiko tinggi terhadap bencana alam gempa bumi. Pada tahun 2004, Kota Nabire diguncang gempa dengan kekuatan 7,2 SR yang menyebabkan kerusakan pada bangunan. Tingkat resiko gempa suatu daerah dinyatakan dengan intensitas MMI (Modified Mercalli Intensity) yang diklasifikasikan berdasarkan nilai Percepatan Tanah Maksimum (Peak Ground Acceleration, PGA). Di dalam menentukan PGA digunakan Metode Empiris Donovan dengan menggunakan dua parameter yaitu magnitudo dan jarak hiposentrum. Hasil perhitungan PGA dan Klasifikasi MMI di Kota Nabire dinyatakan dalam citra dua dimensi. Hasil penelitian ini menunjukan bahwa nilai PGA tertinggi yang diperoleh dengan menggunakan Metode Empiris Donovan adalah 339 gal dan digolongkan ke dalam kategori resiko sangat besar 1 dengan intensitas MMI IX-X. Nilai risiko gempa bumi dengan menggunakan nilai percepatan tanah maksimum Metode Empiris Donovan lebih kecil daripada nilai risiko gempa bumi Kementerian Pekerjaan Umum Republik Indonesia.
Kualitas Minyak Bekas Penggorengan Jajanan Berdasarkan Kadar Asam Lemak Bebas Di Kelurahan Amban Kecamatan Manokwari Barat Kapitarauw, Charlota Angelina; Santoso, Bimo Budi; Darma Santi , Darma Santi
Jurnal Natural Vol. 19 No. 2 (2023): Jurnal Natural
Publisher : FMIPA Universitas Papua

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30862/jn.v19i2.244

Abstract

Analysis of the quality of used frying oil for snacks in the Amban Village, Manokwari Regency has been carried out. Parameters tested were color, water content, free fatty acids and acid number. The results of the analysis of the five samples from the five frying places showed varied results. In plain view the colors of the five samples still met the quality standard, except for sample A. Of the five samples analyzed, the water content of all samples still met the SNI-01-3741-2002 quality standard, which is still below 0.1% (w/b). The acid number content test of the five samples ranged from 0.36 to 1.135 mg KOH/g. Of the five samples tested, two samples exceeded the quality standard requirement 1, namely samples A and D, each with an acid number of 1.005 and 1.135. The free fatty acid content of the five tested samples ranged from 1.67 to 5.67%. There were two samples that exceeded the quality standard (SNI-01-3741-2002), namely samples A and D with acid content of 5.04% and 5.67%, respectively. The test results show that the quality of used frying oil still has 3 samples that meet the quality standards, namely samples B, C and E and 2 samples that do not meet the required quality standards, namely A and D.
SNP PADA GEN KEMOKIN C-C MOTIF LIGAN 7 (CCL7) PENDERITA STROKE DI KABUPATEN MANOKWARI Simamora, Muti Dornita; Islam , Muhammad Fajar; Taher, Achmad
Jurnal Natural Vol. 19 No. 2 (2023): Jurnal Natural
Publisher : FMIPA Universitas Papua

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30862/jn.v19i2.245

Abstract

Chemokines are key components in the development of chronic disease. Chemokine C-C motif ligan 7 (CCL7) is one of the chemokines believed to be associated with the pathology of atherosclerosis that causes stroke. CCL7 may play a role in inflammatory events by attracting macrophages and moncytes to further amplify inflammatory processes and contribute to atherosclerosis progression. Common Genetic variation in CCL7 gene has been associated with atherosclerosis progress, so the main objective of this study was identification of polymorphism of CCL7 gene in stroke patients. Five blood samples were taken from five patients suffering from stroke. The DNA of the blood samples were extracted, amplified its CCL7 gene, and sequenced. The results showed a sequence of 1151 bp consisting of regulator, exon 1, intron and exon 2. One polymorphic sites were found in the intron 1 region, at position 1447. The SNP genotype identified was TC.
TRANSESTERIFIKASI MINYAK GORENG BEKAS MENGGUNAKAN KATALIS DARI LIMBAH GERGAJIAN KAYU MATOA (Pometia pinnata): VARIASI RASIO MOL METANOL TERHADAP MINYAK Aronggear, Pitornela Ribka; Santi, Darma; Langsa, Markus Heryanto; Lisna Efiyanti, Lisna Efiyanti
Jurnal Natural Vol. 20 No. 1 (2024): Jurnal Natural
Publisher : FMIPA Universitas Papua

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30862/jn.v20i1.247

Abstract

Utilization of the sawn waste of matoa (Pometia pinnata) wood from Manokwari is carried out to provide an alternative choice of transesterification reaction catalyst sources that utilize wood processing waste materials. This study aimed to determine the character of the synthetic ash material by calcination method at 500 °C. In addition to testing the catalytic activity of synthetic wood ash in the transesterification reaction of used cooking oil, the mole ratio of methanol to used cooking oil was 3:1 and 9:1. The characterization results indicated the alkali metal components, in the form of Na and K, were respectively 20.7750 and 4.8625 mg/L. The content of alkaline earth metals in the form of Ca is 27.3125 mg/L. The percentage yield of transesterification or total methyl ester conversion at a ratio of 3:1 was 47.24%. Product distribution at a ratio of 3:1, namely methyl palmitate (26.34%) and methyl oleate (20.90%). The yield percentage of transesterification or total methyl ester conversion at a ratio of 9:1 was 64.74%. Product distribution at a ratio of 9:1, namely methyl palmitate (31.70%) and methyl oleate (33.04%).

Page 15 of 16 | Total Record : 160

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