{"title":"Geographically Weighted Regression Modeling with Adaptive Gaussian Kernel Weighting on GRDP in Indonesia","authors":"Frangly Elviano Tangka, Djoni Hatidja, W. Weku","doi":"10.35799/jis.v24i2.50366","DOIUrl":"https://doi.org/10.35799/jis.v24i2.50366","url":null,"abstract":"The purpose of this study is to determine the variables that affect Gross Regional Domestic Product (GRDP) in Indonesia in 2022 using Geographically Weighted Regression (GWR) with Adaptive Gaussian kernel weighting function. The data used in this study uses secondary data taken from the website of the Central Bureau of Statistics. The variables used are gross regional domestic product of 34 provinces in Indonesia (Y, in billion rupiah), labor force participation rate (X1, in %), foreign investment (X2, in million dollars), open unemployment rate (X3, in %) and human development index (X4, in %). Data were analyzed using GWR with adaptive gaussian kernel weighting function. GRDP in all provinces on the island of Sumatra (11 provinces), DKI Jakarta province, Banten province, and West Kalimantan province are influenced by foreign investment (X2) and human development index (X4). Meanwhile, GRDP in the other 19 provinces is only influenced by foreign investment (X2). GWR model with adaptive gaussian kernel weighting function is formed differently for each province in Indonesia.\u0000Keywords: Adaptive gaussian kernel; GWR; gross regional domestic product","PeriodicalId":17715,"journal":{"name":"JURNAL ILMIAH SAINS","volume":"98 48","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141359365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. S. Djarkasi, M. Sumual, Lana E. Lalujan, Ambar Kurnia, Jeanet Rotulung
{"title":"Antioxidant Activity of Virgin Coconut Oil Emulsion Drink with The Addition of Cinnamon (Cinnamomum burmanii)","authors":"G. S. Djarkasi, M. Sumual, Lana E. Lalujan, Ambar Kurnia, Jeanet Rotulung","doi":"10.35799/jis.v24i1.52832","DOIUrl":"https://doi.org/10.35799/jis.v24i1.52832","url":null,"abstract":"ABSTRACT\u0000The aims of this study were to analyse the antioxidant activity and to determine the maximum concentration of cinnamon extract that can improve sensory attributes of VCO emulsion drink. The research method used is a completely randomized design (CRD) with five concentrations of cinnamon extract, i.e., 0% (P1), 2% (P1), 4% (P2), 6% (P3), and 8% (P3). Each treatment was triplicated. The results showed that all treatments exhibited stable emulsion with 0% creaming index. VCO emulsion drink with cinnamon extract contained total phenol ranged from 19.88 mg GEA/100 g to 28.58 mg GEA/100 g, with increasing antioxidant activity, expressed as percentage of inhibition, where P1: 80.35%; P1: 85.59%; P2: 86.38%, P3: 87.43%, and P4: 88.54%, respectively. It was concluded that cinnamon extract could increase the antioxidant activity of VCO emulsion drinks. Increasing percentage of cinnamon extract can increase the total phenol content, hence increase the inhibitory power on the formation of peroxide compounds. The addition of 6% cinnamon is the maximum limit that can improve the panellists’ liking for the overall sensory attributes of the VCO emulsion drink.\u0000Keywords: Antioxidant activity; cinnamon; VCO emulsion","PeriodicalId":17715,"journal":{"name":"JURNAL ILMIAH SAINS","volume":"96 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140707622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Groundwater Study Using Vertical Electrical Sounding (VES) Data Based on Resistivity and Porosity of Rocks in Kampung Melayu, Bengkulu City","authors":"Tella Dwi Syaputri, Suhendra Suhendra, Halauddin Halauddin, Liza Lidiawati, Risma Nurhidayah","doi":"10.35799/jis.v24i1.54133","DOIUrl":"https://doi.org/10.35799/jis.v24i1.54133","url":null,"abstract":"This research aims to identify groundwater based on the value of resistivity and porosity of rocks, which are important parameters in the management of groundwater resources and Development Planning in the region. This groundwater research using Vertical Electrical Sounding (VES) data based on the value of resistivity and porosity of rocks was carried out by measuring resistivity using the (VES) method at 20 sounding points located in Kampung Melayu District, Bengkulu City. The VES method is one of the approaches in the geoelectric method to determine the lithological characteristics of subsurface rocks. Resistivity Data obtained were then inverted and analyzed and interpreted to obtain lithology of subsurface rocks and groundwater level distribution in Kampung Melayu, Bengkulu City. The results showed the presence of groundwater based on low resistivity anomaly values with a range of values from 5 to 30 meters in the West and 10 to 50 meters in the East, with resistivity values ranging between 5 Ω.m up to 45 Ω.m. This research is expected to make a significant contribution to the management of groundwater resources in the District of Kampung Melayu, Bengkulu City and can be the basis for development planning in the area. In addition, it is hoped that the results of this research can be a reference for further research in the field of hydrogeology and groundwater modeling.\u0000Keywords: Aquifer; geoelectricity; groundwater; porosity; resistivity","PeriodicalId":17715,"journal":{"name":"JURNAL ILMIAH SAINS","volume":"70 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140711112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gabriella Setligt, C. Montolalu, Y. Langi, J. Kekenusa, Jantje D Prang, M. Mananohas, Charles E. Mongi
{"title":"Susceptible-Infected-Recovered Model of Mathematics Anxiety Behavior on Students' Mathematics Study Results at Aquino Catholic High School Amurang","authors":"Gabriella Setligt, C. Montolalu, Y. Langi, J. Kekenusa, Jantje D Prang, M. Mananohas, Charles E. Mongi","doi":"10.35799/jis.v24i1.51387","DOIUrl":"https://doi.org/10.35799/jis.v24i1.51387","url":null,"abstract":"This study aims to see the spread of mathematics anxiety behavior on the results of students' mathematics studies at Aquino Catholic High School Amurang by using the SIR (Susceptible-Infected-Recovered) mathematical model. A total of 88 samples were collected and categorized into three groups based on predetermined criteria. These groups consisted of 47 students categorized as susceptible, 27 as infected, and 14 as recovered. The parameters in this study measure the rate of change within these three groups over a 365-day period, equivalent to one year. Two equilibrium points are obtained that can interpret populations free from math anxiety behavior or endemic math anxiety behavior. The stability analysis of the two equilibrium points shows that the equilibrium point free from math anxiety behavior is locally asymptotically stable. Additionally, this study also reveals that math anxiety behavior will disappear in less than 40 days through the basic reproduction number (Ro) obtained, which is 0.99 or less than 1.\u0000Keywords: Amurang; mathematics anxiety; SIR model","PeriodicalId":17715,"journal":{"name":"JURNAL ILMIAH SAINS","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140714244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Runtunuwu, Edy F. Lengkong, Stella Tulung, Deisire N.S. Darus, Riung Tumambo
{"title":"Assimilate Partition of Potato (Solanum tuberosum L.) as Response to Combination of Paclobutrazol and Nitrogen","authors":"S. Runtunuwu, Edy F. Lengkong, Stella Tulung, Deisire N.S. Darus, Riung Tumambo","doi":"10.35799/jis.v24i1.52823","DOIUrl":"https://doi.org/10.35799/jis.v24i1.52823","url":null,"abstract":"Increasing the productivity of potato (Solanum tuberosum L.) can be done by increasing biological production (biomass) and the ability to convert (partition) assimilate/photosynthate into economic results (tubers). The aim of this research is to find a better combination of paclobutrazol (PBZ) application and nitrogen (N) fertilization for tuber partition assimilate of potato. The experiment was conducted in Randomized Block Design (RBD) with three replications. The treatment was consists of nine combinations of PBZ treatments and N fertilization as follows: 1) 3 kg PBZ/ha + 200 kg N/ha, 2) 3 kg PBZ/ha + 250 kg N/ha, 3) 3 kg PBZ/ha + 300 kg N/ha, 4) 3,5 kg PBZ/ ha + 200 kg N/ha, 5) 3,5 kg PBZ/ha + 250 kg N/ha, 6) 3,5 kg PBZ/ha + 300 kg N/ha, 7) 4 kg PBZ/ha + 200 kg N/ha, 8) 4 kg PBZ/ha + 250 kg N/ha, 9) 4 kg PBZ/ha + 300 kg N/ha. The research results showed that at the beginning of growth up to 42 DAP (day after plan), the assimilate (dry material) was directed towards stem and leaf (shoot) growth. Next, at 56 DAP to 84 DAP the assimilate is allocated for tuber growth. The combination of 4 kg PBZ/ha + 200 kg N/ha produces the largest tuber weight\u0000Keywords: Potato (Solanum tuberosum L); nitrogen; paclobutrazol; partition assimilate","PeriodicalId":17715,"journal":{"name":"JURNAL ILMIAH SAINS","volume":"126 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140725733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Muh. Qodri, U. Mukhaiyar, Vira Ananda, Siti Maisaroh
{"title":"Comparison of Stock Prediction Using ARIMA Model with Multiple Interventions of Step and Pulse Functions","authors":"Muh. Qodri, U. Mukhaiyar, Vira Ananda, Siti Maisaroh","doi":"10.35799/jis.v24i1.51269","DOIUrl":"https://doi.org/10.35799/jis.v24i1.51269","url":null,"abstract":"Stock price predictions based on technical analysis using historical data help investors determine the optimal time to buy or sell shares with the aim of achieving maximum profits. The aim of this research is to compare the results of Kimia Farma's share price predictions using the ARIMA model with intervention analysis of two variables at once, namely the pulse function and the step function. This is the novelty of this research. The data used in this research is daily data on Kimia Farma shares from the period 16 April 2018 to 14 April 2023. The best model produced is ARIMA (0,1,1) with intervention, shown by a MAPE value of 0.3356% and an RMSE of 0.3356%. 4.03. Kimia Farma's share price prediction for the next five days is 906.5548; 905.7875; 905.0206; 904.2542; 903.4882 rupiah. An increase in share prices occurred after the intervention in the period 15 April 2023 to 19 April 2023.\u0000Keywords: ARIMA; intervention model; step and pulse function; kimia farma","PeriodicalId":17715,"journal":{"name":"JURNAL ILMIAH SAINS","volume":"91 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140235104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Performa Kernel pada Model Geographically Weighted Regression untuk Menentukan Faktor-faktor Yang Mempengaruhi Indeks Pembangunan Manusia di Provinsi Sulawesi Selatan","authors":"Angelia Fransisca Adatunaung, Djoni Hatidja, Winsy Christo Deilan Weku","doi":"10.35799/jis.v23i2.48867","DOIUrl":"https://doi.org/10.35799/jis.v23i2.48867","url":null,"abstract":"Penelitian ini bertujuan untuk menentukan performa kernel dengan memilih model terbaik dari tiga jenis kernel yang berbeda dan menentukan faktor-faktor yang mempengaruhi Indeks Pembangunan Manusia (IPM) di Provinsi Sulawesi Selatan dengan menggunakan model GWR. Pada penelitian ini memakai data sekunder dari Badan Pusat Statistik Provinsi Sulawesi Selatan dengan variabel independen yaitu IPM (Y) dan variabel dependen yaitu umur harapan hidup (UHH) (X1), pengeluaran perkapita (X2) dan produk domestik regional bruto (PDRB) (X3) serta nilai longitude dan latitude yang diperoleh dari aplikasi google maps. Metode yang dilakukan dalam penelitian ini yaitu metode GWR dan kernel yang dipakai yaitu kernel gaussian, kernel bisquare dan kernel tricube. Hasil penelitian ini menunjukkan bahwa model terbaik yang dapat digunakan yaitu model GWR dengan kernel tricube dengan nilai AIC = 81,5543700 dan R2 = 90,67 persen. Model GWR kernel tricube mampu menentukan faktor-faktor yang mempengaruhi indeks pembangunan manusia di Sulawesi Selatan tahun 2022. Kata Kunci: Geographically Weighted Regression; indeks pembangunan manusia; kernel tricube","PeriodicalId":17715,"journal":{"name":"JURNAL ILMIAH SAINS","volume":"279 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135871779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Eva Marliana, Novia Rahmawati Isyahro, Nanang Tri Widodo
{"title":"Uji Aktivitas Tabir Surya Ekstrak Metanol, Fraksi N-Heksana, Etil Asetat Dan Metanol-Air Daun Keledang (Artocarpus lanceifolius Roxb) Secara In Vitro","authors":"Eva Marliana, Novia Rahmawati Isyahro, Nanang Tri Widodo","doi":"10.35799/jis.v23i2.51543","DOIUrl":"https://doi.org/10.35799/jis.v23i2.51543","url":null,"abstract":"Uji aktivitas tabir surya dari daun keledang (Artocarpus lanceifolius Roxb.) secara in vitro telah dilakukan. Penelitian ini bertujuan untuk mengetahui sifat tabir surya ekstrak metanol, fraksi n-heksana, etil asetat dan metanol-air dari daun keledang. Metode yang digunakan secara in vitro menggunakan spektrofotometer UV-Vis. Berdasarkan hasil uji fitokimia diketahui bahwa ekstrak metanol mengandung flavonoid, fenolik dan steroid/ triterpenoid. Fraksi n-heksana mengandung steroid/triterpenoid dan kuinon. Fraksi etil asetat mengandung flavonoid, fenolik, steroid/triterpenoid dan kuinon. Fraksi metanol-air mengandung flavonoid dan fenolik. Ekstrak metanol, fraksi n-heksana, etil asetat dan metanol-air juga menunjukkan adanya aktivitas tabir surya, berdasarkan nilai SPF (Sun Protection Factor) pada konsentrasi 25; 50; 100; 150; 200 dan 250 mg/L. Ekstrak metanol memiliki nilai SPF secara berturut adalah 4,44; 7,36; 15,15; 22,47; 31,25 dan 37,31 (minimal-ultra). Fraksi n-heksana memiliki nilai SPF secara berturut adalah 1,37; 2,23; 5,07; 7,51; 10,01 dan 12,74 (minimal-maksimal). Fraksi etil asetat memiliki nilai SPF secara berturut adalah 3,32; 7,20; 13,03; 19,54; 25,97 dan 30,60 (minimal-ultra). Fraksi metanol-air memiliki nilai SPF berturut adalah 5,23; 10,87; 21,48; 30,89; 36,01 dan 38,52 (sedang-ultra). Nilai SPF meningkat seiring dengan dengan peningkatan konsentrasi karena semakin tinggi konsentrasi maka semakin banyak senyawa aktif tabir surya yang terkandung dalam ekstrak dan fraksi tersebut. Pada daun keledang, fraksi metanol-air memiliki aktivitas tabir surya tertinggi diikuti ekstrak metanol, fraksi etil asetat dan fraksi n-heksana. Daun keledang berpotensi sebagai bahan tabir surya. Kata kunci: Artocarpus lanceifolius; in vitro; tabir surya","PeriodicalId":17715,"journal":{"name":"JURNAL ILMIAH SAINS","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135928849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Penerapan Regresi Nonparametrik Spline dan Deret Fourier Untuk Memodelkan Produk Domestik Regional Bruto di Indonesia","authors":"Marklif Esriy Mocodompis, Deiby Tineke Salaki, Djoni Hatidja","doi":"10.35799/jis.v23i2.48868","DOIUrl":"https://doi.org/10.35799/jis.v23i2.48868","url":null,"abstract":"Tujuan penelitian ini adalah memodelkan PDRB (Produk Domestik Regional Bruto) di Indonesia dengan regresi nonparametrik spline dan Deret Fourier. Data yang digunakan adalah PDRB 34 Provinsi di Indonesia dengan variabel prediktor tingkat partisipasi angkatan kerja, investasi penanaman modal asing, pendapatan asli daerah, upah minimum provinsi, dan indeks pembangunan manusia. Pada regresi nonparametrik spline dilakukan penentuan titik knot yang paling optimal dengan satu sampai tiga titik, sehingga didapatkan titik knot yang paling optimal adalah dengan tiga titik knot berdasarkan nilai GCV (Generalized Cross Validation) paling minimum. Pada regresi nonparametrik Deret Fourier dilakukan perhitungan satu sampai tiga titik osilasi, didapat titik osilasi optimal adalah tiga osilasi berdasarkan nilai GCV paling minimum. Maka model regresi nonparametrik spline yang terbaik menggunakan tiga titik knot dan untuk Deret Fourier menggunakan tiga titik osilasi, dalam memodelkan PDRB di Indonesia. Kata Kunci: Deret Fourier; regresi nonparametrik; spline; titik knot","PeriodicalId":17715,"journal":{"name":"JURNAL ILMIAH SAINS","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136105227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lusiana Eka Sari, Audy D. Wuntu, Max R.J. Runtuwene, Lidya Irma Momuat
{"title":"Fotodegradasi Rhodamin B Menggunakan Komposit Perak Fosfat- Hidroksiapatit dari Tulang Ikan Cakalang (Katsuwonus pelamis)","authors":"Lusiana Eka Sari, Audy D. Wuntu, Max R.J. Runtuwene, Lidya Irma Momuat","doi":"10.35799/jis.v23i2.50469","DOIUrl":"https://doi.org/10.35799/jis.v23i2.50469","url":null,"abstract":"Hidroksiapatit (HAp) yang diperlakukan dengan perak dapat menghasilkan perak fosfat (Ag3PO4) yang merupakan material semikoduktor dan dapat mendegradasi pewarna sintetik. Penelitian ini dikerjakan dengan tujuan mensintesis suatu komposit dengan komponen utama HAp dari tulang ikan cakalang (Katsuwonus pelamis) dan Ag3PO4 yang kemudian digunakan untuk mendegradasi pewarna sintetik rhodamin B (RB) dalam larutan dengan pelarut air. Karakterisasi material yang dihasilkan dikerjakan menggunakan teknik-teknik Difraksi Sinar-X (XRD), Mikroskopi Pemindaian Elektron bersama dengan Sinar-X Disperesi Energi (SEM-EDX), dan Spektroskopi Infra Merah Fourier-Transform (FTIR). Fotodegradasi rhodamin B diuji di bawah radiasi sinar tampak dengan variasi jumlah komposit dan intensitas penyinaran. Hasil karakterisasi menunjukkan terbentuknya komposit Ag3PO4/Hap dan uji fotodegradasi memperlihatkan bahwa semakin besar jumlah fotokatalis dan intensitas cahaya yang digunakan, semakin banyak pewarna sintetik yang terdegradasi. Kata kunci: Ag3PO4; fotodegradasi; hidroksiapatit; rhodamin B; tulang ikan cakalang","PeriodicalId":17715,"journal":{"name":"JURNAL ILMIAH SAINS","volume":"11 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136135304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}