Article Per Year (5 Year)
p-Index From 2021 - 2026
1.116
P-Index
This Author published in this journals
All Journal Jurnal Arsitektur Jurnal Matematika & Sains Journal of Mathematical and Fundamental Sciences Journal of Engineering and Technological Sciences JOURNAL ONLINE OF PHYSICS JOIV : International Journal on Informatics Visualization Jurnal Biodjati Saintifik : Jurnal Matematika, Sains, dan Pembelajarannya PROSIDING SEMINAR NASIONAL FISIKA (E-JOURNAL)
Acep Purqon Acep Purqon
Institut Teknologi Bandung
Astronomy Biochemistry, Genetics & Molecular Biology Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Earth & Planetary Sciences Electrical & Electronics Engineering Energy Engineering Environmental Science Mathematics Physics Other

Published : 11 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 11 Documents
Search

 1   2 
The Effects of Atomic Substitutions (Bismuth, Gallium, Arsenic) on Electronic and Magnetic Properties of Carbon Nanotubes Aprilia, Ely; Muttaqien, Fahdzi; Purqon, Acep; Suprijadi, Suprijadi
Jurnal Matematika dan Sains Vol 20 No 1 (2015)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Investigations of carbon nanotubes (CNT) properties by substituting impurity atoms are interesting, since the the defects show different properties and potentially wide applications. In this paper, we investigate the effects of atomic substitutions (Bismuth, Gallium, Arsenic) on electronic and magnetic properties of CNT by using Density Functional Theory method with Generalized Gradient Approximation. Our results show that Bismuth and Arsenic doped on zigzag CNT (10, 0) give the band gap and magnetic moment 0.19 eV and 2 μB, respectively. In contrast, Gallium doped shows no band gap and change the semiconductor properties of zigzag edge CNT (10, 0) into metal. Furthermore, the moment magnetic for Gallium-Arsenide doped CNT (10, 0) is 1 μB. Keywords: Atomic substitution, Band gap, Carbon nanotubes (CNT), DOS, Impurity.   Pengaruh Atom Pengganti (Bismut, Galium, Arsenik) pada Sifat Elektronik dan Magnetik Karbon Nanotube Abstrak Kecacatan pada struktur CNT mengakibatkan adanya perubahan sifat elektronik dan magnetiknya. Perubahan sifat inilah yang menyebabkan CNT  menarik untuk diteliti karena berpotensi memiliki aplikasi yang luas. Pada penelitian ini, dibahas mengenai  efek dari atom pengganti (Bismut, Galium dan Arsen) pada sifat elektronik dan magnetik CNT(10,0) yang dihitung dengan menggunakan teori fungsional kerapatan dan Generalized Gradient Approximation. Hasilnya menunjukan bahwa atom pengotor Bismut dan Arsen pada CNT (10,0) menghasilkan band gap sebesar 0.19 eV dan momen magnetik sebesar 2 μB. Sedangkan atom pengotor Galium tidak menghasilkan band gap pada CNT(10,0) dan mengubah sifat semikonduktor CNT(10,0) menjadi metal. Dari perhitungan didapatkan juga magnetik momen pada CNT (10,0) dengan atom pengotor Galium dan Arsen sebesar 1 μB. Kata kunci: Atom pengganti, Band gap, Karbon nanotube, DOS, Ketidakmurnian.
Simulasi Aliran Plasma dengan Variasi Kecepatan Injeksi Plasma pada Potensial Penghalang dalam Posisi Melayang Faisal, Muliady; Purqon, Acep
Jurnal Saintifik Vol 4, No 2 (2018): volume 4 nomor 2 juli 2018
Publisher : Fakultas MIPA UNSULBAR

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31605/saintifik.v4i2.179

Abstract

Dalam penelitian ini akan diperlihatkan bentuk difusi aliran plasma yang terjadi akibat variasi kecepatan injeksi plasma pada sebuah potensial penghalang dalam posisi melayang pada kasus distribusi kerapatan muatan dan daerah potensial listrik yang diturunkan dari persamaan Poisson. Metode yang digunakan dalam penelitian ini adalah Particle-In-Cell (PIC). Dalam metode PIC, elektron dan proton merupakan sumber dari plasma. Secara numerik step waktu yang digunakan dalam penelitian yaitu setiap 1 detik dengan periode plasma selama 200 detik dan grid yang digunakan yaitu 20 x 20. Adapun potensial penghalangnya berbentuk persegi. Dari variasi kecepatan injeksi berpengaruh terhadap kerapatan muatan sehingga jika kecepatan injeksinya diperbesar maka akan terdapat daerah kosong yang tidak terisi dibelakang potensial penghalang. Sedangkan untuk daerah potensial listrik jika kecepatan injeksi plasmanya diperbesar maka daerah dibelakang potensial penghalang akan terdapat daerah yang berpotensial yang lebih kecil.Kata kunci: Plasma, PIC, Potensial penghalang
Model of Land Cover Change Caused by Toll Road Access Using Cellular Automata in Sumatra Island Zenia F Saraswati; Acep Purqon; IB Ilham Malik; Dion Awfa; Fajriharish Nur Awan; M Risky; Melisa Vira Permata; Maulidya Paramitha; Iqbal Wira Menanza; Nasrul Putra
JURNAL ARSITEKTUR Vol 12, No 1 (2022): Januari 2022
Publisher : Universitas Bandar Lampung (UBL)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36448/ja.v12i1.2323

Abstract

The use of land is a part of the fulfillment of human needs. The establishment of a large-scale infrastructure project often triggers an increase in land cover around its infrastructure project. Most of the increase in built up land tends to occur in areas that are traversed by or located near main accessibility routes such as toll roads. Although the construction of toll roads can improve accessibility between regions, land is a limited resource. So that it becomes the basis for researchers to identify the changes in land use in regencies and cities on the island of Sumatra that are crossed by toll roads that have been operating. The goal of land use change analysis is to give a description or explanation, predict, look at the effects, and make a decision (prescription). This research was conducted by identifying the changes in the existing land cover and predicting the land cover using cellular automata. Cellular automata have proven to be a method that is suitable for predicting the dynamics of land use through spatial simulation. The results show that there was an increase in the amount of land built from early 2017 to 2030. The covered land is developed around the toll gate after it is actively operated. In all provinces studied, deviation discrepancies were found in the conservation and cultivation areas. Deviations that occur in conservation areas need to be considered as there should be no land built in these areas, which means that there are cultivation activities in the conservation areas.
Global Inversion of Grounded Electric Source Time-domain Electromagnetic Data Using Particle Swarm Optimization Cahyo Aji Hapsoro; Wahyu Srigutomo; Acep Purqon; Warsa warsa; Doddy Sutarno; Tsuneomi Kagiyama
Journal of Engineering and Technological Sciences Vol. 53 No. 1 (2021)
Publisher : Institute for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2021.53.1.1

Abstract

Global optimization inversion of grounded wire time-domain electromagnetic (TDEM) data was implemented through application of the particle swarm optimization (PSO) algorithm. This probabilistic approach is an alternative to the widely used deterministic local-optimization approach. In the PSO algorithm, each particle that constitutes the swarm epitomizes a probable geophysical model comprised by subsurface resistivity values at several layers and layer thicknesses. The forward formulation of the TDEM problem for calculating the vertical component of the induced magnetic field is first expressed in the Laplace domain. Transformation of the magnetic field from the Laplace domain into the time domain is performed by applying the Gaver-Stehfest numerical method. The implementation of PSO inversion to the TDEM problem is straightforward. It only requires adjustment of a few inversion parameters such as inertia, acceleration coefficients and numbers of iteration and particles. The PSO inversion scheme was tested on synthetic noise-free data and noisy synthetic data as well as to field data recorded in a volcanic-geothermal area. The results suggest that the PSO inversion scheme can effectively solve the TDEM 1D stratified earth problem. 
PEMODELAN ALIRAN DEBRIS FLOW UNTUK ANALISIS POTENSI LONGSORAN STUDI KASUS: PEGUNUNGAN FISHHWAK, CALIFORNIA Rustan Rustan; Acep Purqon
JOURNAL ONLINE OF PHYSICS Vol. 2 No. 1 (2016): JOP (Journal Online of Physics) Vol 2 No 1
Publisher : Prodi Fisika FST UNJA

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22437/jop.v2i1.3446

Abstract

Aliran debris (debris flow) merupakan aliran yang terdiri dari campuran material halus berukuran kecil (clay, lumpur, pasir) sampai material berukuran kasar (kerikil, bongkahan bebatuan) dengan sejumlah volume air. Material debris flow mengalir dengan volume besar dan kecepatan tinggi menghasilkan momentum yang bisa menyebabkan kerusakan infrastruktur, lingkungan, bahkan korban jiwa. Interaksi fisis antara campuran air dan material debris melibatkan interaksi yang sangat kompleks membuat mekanisme transpor aliran debris sulit untuk dikaji menggunakan pendekatan numerik. Prediksi distribusi aliran debris dapat dilakukan menggunakan pendekatan statistik empirik. Pendekatan ini dengan menghubungkan parameter volume debris flow dengan luas genangan yang akan dihasilkan. Analisis menggunakan pendekatan statistik empirik didukung oleh data spasial dapat dijalankan menggunakan perangkat lunak DFLOWZ.  Parameter input dalam DFLOWZ yaitu data digital ketinggian (DEM), data polyline, dan volume debris flow.  DFLOWZ berhasil diterapkan pada debris flow di pegunungan Alpen, Italia. Pada penelitian ini, DFLOWZ diaplikasikan di salah satu daerah yang pernah terjadi debris flow di wilayah California, Amerika Serikat. Didapatkan luas genangan debris flow sebesar 285.447 m2. Kata kunci: debris flow, pemodelan, DFLOWZ
Prediction of Carbon Monoxide Concentration with Variation of Support Vector Regression Kernel Parameter Value Halawa Ernwati; Yazid Bindar; Acep Purqon; Wahyu Srigutomo
Journal of Mathematical and Fundamental Sciences Vol. 54 No. 1 (2022)
Publisher : Institute for Research and Community Services (LPPM) ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.math.fund.sci.2022.54.1.3

Abstract

Human and industrial activities produce air pollutants that can cause a decline in air quality. In urban areas, transportation activities are the main source of air pollution. One of the emitted air pollutants produced by transportation is carbon monoxide (CO). The understanding of CO concentration is crucial since its overabundance beyond a certain limit will have a negative impact on human health and the environment. In this study, the support vector regression (SVR) method was used to predict CO concentration. The purpose of this study was to predict the hourly CO concentration in the Ujung Berung district, Bandung City, West Java, Indonesia with optimal prediction accuracy. An experiment was carried out by modeling the CO concentration with varying kernel parameter values to obtain accurate prediction results. The suitability of the values between error (ɛ), a trade-off constant (C), and variation mismatch (γ) is vital to obtain optimal prediction results. The results showed that the best prediction accuracy value was 97.68% with kernel parameter values ɛ = 0.02, γ = 30, and C = 0.006. These results may lead to proper decision making on environmental issues and can improve air pollution control strategies.
Simulasi Aliran Plasma dengan Variasi Kecepatan Injeksi Plasma pada Potensial Penghalang dalam Posisi Melayang Muliady Faisal; Acep Purqon
SAINTIFIK Vol 4 No 2 (2018): volume 4 nomor 2 juli 2018
Publisher : Universitas Sulawesi Barat

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (936.373 KB) | DOI: 10.31605/saintifik.v4i2.179

Abstract

Dalam penelitian ini akan diperlihatkan bentuk difusi aliran plasma yang terjadi akibat variasi kecepatan injeksi plasma pada sebuah potensial penghalang dalam posisi melayang pada kasus distribusi kerapatan muatan dan daerah potensial listrik yang diturunkan dari persamaan Poisson. Metode yang digunakan dalam penelitian ini adalah Particle-In-Cell (PIC). Dalam metode PIC, elektron dan proton merupakan sumber dari plasma. Secara numerik step waktu yang digunakan dalam penelitian yaitu setiap 1 detik dengan periode plasma selama 200 detik dan grid yang digunakan yaitu 20 x 20. Adapun potensial penghalangnya berbentuk persegi. Dari variasi kecepatan injeksi berpengaruh terhadap kerapatan muatan sehingga jika kecepatan injeksinya diperbesar maka akan terdapat daerah kosong yang tidak terisi dibelakang potensial penghalang. Sedangkan untuk daerah potensial listrik jika kecepatan injeksi plasmanya diperbesar maka daerah dibelakang potensial penghalang akan terdapat daerah yang berpotensial yang lebih kecil.Kata kunci: Plasma, PIC, Potensial penghalang
VISUALISASI DAN KARAKTERISASI TANAH LONGSORAN STUDI KASUS: KECAMATAN SINJAI TENGAH PROVINSI SULAWESI SELATAN Linda Handayani; Fourier D. E. Latief; Rustan Rustan; Acep Purqon
PROSIDING SEMINAR NASIONAL FISIKA (E-JOURNAL) Vol 4 (2015): PROSIDING SEMINAR NASIONAL FISIKA (E-JOURNAL) SNF2015
Publisher : Program Studi Pendidikan Fisika dan Program Studi Fisika Universitas Negeri Jakarta, LPPM Universitas Negeri Jakarta, HFI Jakarta, HFI

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (629.599 KB)

Abstract

Central Sinjai is one of the sub districts in Sinjai, South Sulawesi Province. Central Sinjai is an area that prone of landslide. This is caused by the dominance of the hills and mountains form and it has a steep slope. Landslide in Sinjai is one of the disasters that are difficult to avoid, because it is one of the consequences of geographic location. Nevertheless, it can be prevented and minimized risks by conducting fundamental research. The aims of this research are to visualize soil landslides samples in 3D. This samples were taken in prone area of landslides with different coordinates. In addition, in this research also analize physis paramater of the samples. This reserach is very important to look up the real condition of the soil landslides. This Research will be a fundamental research to understand the characteristic of landslides in Sinjai, then could be a refference to anticipate and reduce a risk of landslides. Image in 2D were taken by Micro-CT Scanner, Sky Scan 1173. Scanning Process use X-Ray with voltage 130 kV, current 60 μA, and camera resolution 1120x1120 pixel. Then, reconstruction image will be visualized by Data Viewer and CT Vox. CT An is using to characterising physics parameter. The results of this research has showed that landslide soil structure is composed by small grain and the soil have low density. The porosity of soil lanslide is 26,73%. Keywords: Visualisation, Characterisation, Soil Landslides, South Sulawesi
Effect of Growth Space on The Productivity of Maize Using Three Sisters Cultivation with Bee Pollination Nadia Damika Putri; Acep Purqon; Ramadhani Eka Putra
Jurnal Biodjati Vol 8, No 2 (2023): November
Publisher : UIN Sunan Gunung Djati Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15575/biodjati.v8i2.19227

Abstract

he increasing number of food needs is one of the driving factors for increasing agricultural production, but there are constraints on the availability of land. A polyculture system with corn, beans, and pumpkins, commonly known as the three sisters, can create positive interactions that can enhance the growth and development of each plant. This system has a vast potency to be applied to urban farming inside a grow bag because it does not require ample space, the placement of plants is flexible, and it produces a variety of yields. However, it is necessary to assess the effect of growing space on the growth of maize (Zea mays) cultivated by the three-sister system. This study used a completely randomized design with three treatments and six replications. The treatment consists of three planting spaces with various growing bags (treatment A:75 L, B:100 L, and C:200 L). The results of this study showed that the highest corn productivity was in the largest growing space (treatment C), which weighed 318.40 g/cob, and without husks 246.42 g/cob, but not significantly different from treatment B (grow bag 100 L), which weights 316.20 g/cob and without pods of 240.63 g/cob. This study found that the 100 L grow bag was the optimal growing space for planting corn in containers using the three sisters technique.
Geometry Representation Effectiveness in Improving Airfoil Aerodynamic Coefficient Prediction with Convolutional Neural Network Zikri, Arizal Akbar; Defianti, Hanni; Hidayat, Wahyu; Purqon, Acep
JOIV : International Journal on Informatics Visualization Vol 7, No 3 (2023)
Publisher : Society of Visual Informatics

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30630/joiv.7.3.1577

Abstract

Many applications use symmetric or asymmetric airfoils, such as aircraft design, wind turbines, and heat transfer. Each airfoil has different aerodynamic coefficients. Obtaining the aerodynamic coefficients is a must to optimize the airfoil design. Engineers use various methods to get the airfoil aerodynamic coefficients. A prediction method is an approximation approach that effectively reduces time and cost. This article uses convolutional neural networks (CNN) to get approximation values of those coefficients. In CNN, we collect 8920 aerodynamic coefficients for 223 NACA 4 as labels in datasets by using XFOIL at  and  with varying angles of attacks starting  to  with increment of . The simulation results are compared to the experiment using E387 airfoil for validation. Then, airfoil geometries as part of input datasets were transformed into Grayscale and RGB images using the signed distance function (SDF) and mesh algorithm. Each airfoil representation was trained using an 80% dataset and tested using a 20% dataset with Adam as an optimizer to generate each prediction model using modified LeNet-5. We use three different layer depths in modified LeNet-5 to obtain the optimal layer number. There is no remarkable improvement when varying the depth layers, so four layers are used instead. Simulation results show that using an SDF with Fast Marching Method on CNN predicts the most effective for the airfoil’s lift, drag, and pitch moment coefficient with varying angles of attack simultaneously. One can extend the method by using SDF to recognize different flow conditions.
Co-Authors Aprilia, Ely Defianti, Hanni Dion Awfa Doddy Sutarno Faisal, Muliady Fajriharish Nur Awan Fourier D. E. Latief Halawa Ernwati Hapsoro, Cahyo Aji IB Ilham Malik Iqbal Wira Menanza Linda Handayani M Risky Maulidya Paramitha Melisa Vira Permata Muliady Faisal Muttaqien, Fahdzi Nadia Damika Putri Nasrul Putra Ramadhani Eka Putra Ramadhani Eka Putra Rustan Rustan Rustan Suprijadi Suprijadi Tsuneomi Kagiyama Wahyu Hidayat Wahyu Srigutomo Warsa warsa Yazid Bindar Zenia F Saraswati Zikri, Arizal Akbar