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All Journal JOURNAL OF ELECTRICAL AND SYSTEM CONTROL ENGINEERING JOURNAL OF MECHANICAL ENGINEERING, MANUFACTURES, MATERIALS AND ENERGY Jurnal Teknovasi : Jurnal Teknik dan Inovasi Mesin Otomotif, Komputer, Industri dan Elektronika Martabe : Jurnal Pengabdian Kepada Masyarakat Infotekmesin Journal of Applied Engineering and Technological Science (JAETS) Community Development Journal: Jurnal Pengabdian Masyarakat Teknomekanik Jurnal Anugerah: Jurnal Pengabdian Kepada Masyarakat Bidang Keguruan dan Ilmu Pendidikan Mejuajua Automotive Experiences IRA Jurnal Teknik Mesin dan Aplikasinya (IRAJTMA) IRA Jurnal Pengabdian Kepada Masyarakat
Yopan Rahmad Aldori
Universitas Medan Area
Aerospace Engineering Agriculture, Biological Sciences & Forestry Arts Humanities Automotive Engineering Chemical Engineering, Chemistry & Bioengineering Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Decision Sciences, Operations Research & Management Economics, Econometrics & Finance Education Electrical & Electronics Engineering Energy Engineering Health Professions Industrial & Manufacturing Engineering Languange, Linguistic, Communication & Media Materials Science & Nanotechnology Mathematics Mechanical Engineering Public Health Social Sciences Other

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Pemberdayaan generasi muda dalam transisi energi hijau melalui pelatihan teknologi fuel cell Iswandi, Iswandi; Supriatno, Supriatno; Susilawati, Susilawati; Hermanto, Tino; Hasibuan, Samsul Abdul Rahman Sidik; Muliono, Rizki; Royani, Ida; Aldori, Yopan Rahmad
Jurnal Anugerah Vol 7 No 1 (2025): Jurnal Anugerah: Jurnal Pengabdian kepada Masyarakat Bidang Keguruan dan Ilmu Pen
Publisher : Universitas Maritim Raja Ali Haji

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31629/anugerah.v7i1.7174

Abstract

Krisis energi global dan rendahnya literasi energi bersih di kalangan pelajar mendorong perlunya edukasi teknologi alternatif yang berkelanjutan. Kegiatan pengabdian ini dilatarbelakangi oleh kebutuhan untuk meningkatkan wawasan siswa terhadap teknologi energi terbarukan, khususnya fuel cell. Tujuan kegiatan ini adalah untuk memperkenalkan prinsip dasar kerja teknologi fuel cell serta membangun pemahaman dan keterampilan awal siswa Sekolah Menengah Kejuruan (SMK) sebagai bagian dari edukasi transisi energi hijau. Pengumpulan data dilakukan sebagai langkah evaluatif untuk meninjau keberhasilan kegiatan PkM. Tolok ukur keberhasilan ditentukan berdasarkan peningkatan pemahaman kognitif siswa serta tingkat partisipasi dan respons positif terhadap materi pelatihan. Metode pelaksanaan menggunakan pendekatan pelatihan interaktif, pendidikan masyarakat, dan substitusi ipteks. Peserta kegiatan berjumlah lebih dari 50 siswa jurusan Bisnis dan Manajemen di SMK Swasta Nurul Amaliyah Tanjung Morawa. Teknik pengumpulan data mencakup pre-test dan post-test untuk mengukur peningkatan pemahaman, observasi untuk menilai keterlibatan siswa, serta wawancara semi-terstruktur untuk menggali persepsi dan ketertarikan siswa terhadap teknologi energi bersih. Analisis data dilakukan secara deskriptif kuantitatif dan naratif. Hasil menunjukkan adanya peningkatan skor pemahaman peserta dari 42% menjadi 81%, disertai partisipasi aktif dan ketertarikan tinggi terhadap materi. Peserta juga mampu mengaitkan prinsip kerja fuel cell dengan peluang usaha berbasis energi bersih. Kegiatan ini membuktikan bahwa edukasi ipteks lintas disiplin dapat menjembatani kesenjangan pemahaman teknologi dan membentuk kesadaran technopreneurship. Oleh karena itu, model pelatihan ini berpotensi diterapkan secara lebih luas dalam satuan pendidikan vokasi non-teknik untuk mendukung transisi energi nasional.
Inovasi Teknologi Hijau Untuk Masa Depan Dan Peran Keteknikan Dalam Industri Berkelanjutan Di SMA Negeri 1 Tebing Tinggi Rahman Aldori, Yopan; Moerni, Saufa Yardha; Syafitri Rambe, Yunita; Susilawati, Susilawati; Ermita Wulandari, Tika; Muhathir, Muhathir; Maghfirah, Maghfirah
Mejuajua: Jurnal Pengabdian pada Masyarakat Vol. 5 No. 1 (2025): Agustus 2025
Publisher : Yayasan Penelitian dan Inovasi Sumatera (YPIS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.52622/mejuajuajabdimas.v5i1.267

Abstract

Permasalahan lingkungan global yang semakin kompleks mendorong perlunya inovasi teknologi hijau sebagai solusi menuju masa depan yang berkelanjutan. Pendidikan memainkan peran strategis dalam membentuk kesadaran generasi muda terhadap pentingnya menjaga lingkungan dan mengembangkan teknologi ramah lingkungan. Kegiatan pengabdian kepada masyarakat ini dilaksanakan di SMA Negeri 1 Tebing Tinggi dengan tujuan utama untuk meningkatkan pemahaman siswa mengenai konsep teknologi hijau serta memperkenalkan peran keteknikan dalam mendukung industri berkelanjutan. Metode pelaksanaan kegiatan dilakukan secara edukatif dan partisipatif melalui penyampaian materi interaktif, diskusi kelompok, serta sesi tanya jawab yang mendorong keterlibatan aktif peserta. Materi yang disampaikan meliputi pengenalan teknologi hijau, studi kasus penerapannya di berbagai sektor industri, dan peran teknik dalam mendukung transformasi industri yang lebih ramah lingkungan. Hasil kegiatan menunjukkan antusiasme tinggi dari para siswa, yang ditunjukkan melalui keterlibatan aktif selama diskusi dan refleksi positif terkait peningkatan pengetahuan mereka tentang teknologi hijau. Selain memberikan dampak pada siswa, kegiatan ini juga memotivasi pihak sekolah untuk mulai mempertimbangkan integrasi tema lingkungan ke dalam kegiatan belajar mengajar, baik itu dalam bentuk tugas ataupun praktik langsung penggunaan teknologi hijau. Untuk rencana jangka panjang, kegiatan ini dapat menjadi inisiator kerjasama antara tim pengabdian dengan pihak sekolah dalam pelaksanaan praktik penggunaan teknologi hijau di sekolah.
OPTIMALISASI PENGOLAHAN LIMBAH PLASTIK PADA KELOMPOK TANI JATI REJO-1 DI DESA PARTIMBALAN, BANDAR MASILAM, KABUPATEN SIMALUNGUN Jubaidah, Jubaidah; Suprapto, Suprapto; Iskandar, Henry; Puspita, Riana; Aldori, Yopan R.; Syahra, Assyfa; Aryanta Sembiring, Robi; Diansyah, Diansyah; Meidiansyah, Fadli
Martabe : Jurnal Pengabdian Kepada Masyarakat Vol 7, No 9 (2024): MARTABE : JURNAL PENGABDIAN MASYARAKAT
Publisher : Universitas Muhammadiyah Tapanuli Selatan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31604/jpm.v7i9.3544-3551

Abstract

Kegiatan Pengabdian Masyarakat (PKM) ini bertujuan untuk mengoptimalkan pengolahan limbah plastik di Kelompok Tani Jati Rejo-1, Desa Partimbalan, Bandar Masilam, Kabupaten Simalungun. Metode yang digunakan meliputi sosialisasi, pelatihan, dan pendampingan teknis dalam pengolahan limbah plastik menjadi produk yang bernilai ekonomis. Hasil menunjukkan adanya peningkatan pengetahuan dan keterampilan anggota kelompok tani dalam mengolah limbah plastik. Hasil kegiatan ini berhasil meningkatkan kesadaran lingkungan dan perekonomian masyarakat setempat.
KAJIAN TEKNOLOGI PEMBUATAN GULA SEMUT AREN ORGANIK PADA KELOMPOK TANI JATI REJO 1 DESA PARTIMBALAN Suprapto, Suprapto; Iskandar, Henry; Daryanto, Eka; Listiyanto, Listiyanto; Riadi, Selamat; Jubaidah, Jubaidah; R. Nurfazriah, Latifah; R. Aldori, Yopan; Giovan Panjaitan, Asido; Firmansyah Nasution, Taufik
Martabe : Jurnal Pengabdian Kepada Masyarakat Vol 7, No 8 (2024): MARTABE : JURNAL PENGABDIAN MASYARAKAT
Publisher : Universitas Muhammadiyah Tapanuli Selatan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31604/jpm.v7i8.3004-3012

Abstract

Produk Gula semut aren organik (GSAO) merupakan komoditi yang sangat diminati dipasar nasional dan insternasional. Pengembangan teknologi pengering sangat diperlukan untuk mendapatkan kualitas GSAO yang dapat memenuhi standar pasar. Mesin pengering jenis rak yang dimiliki mitra kelompok tani jati rejo-1 (KTJR-1) belum memenuhi standar teknis pengering. Kegiatan Pengabdian kepada Masyarakat (PKM) bertujuan penerapan ilmu dan ahli teknologi dalam pengembangan teknologi pengeringan rotary drying machine (RDM) untuk meningkatkan kuantitas dan kualitas produk GSAO. Metode pelaksanaan PKM mencakup survei, observasi, pelatihan dan pendampingan, serta analisis mesin pengering jenis rak yang ada di mitra. Hasil rancangan mesin dan perpindahan panas dapat dijadikan dasar oleh mitra dalam fabrikasi sebuah mesin pengering dengan menerapkan prinsip perpindahan panas yang effisien untuk meningkatkan kualitas dan efisiensi produksi GSAO.
Uniaxial and biaxial hot pressing of PVDF films: A pathway toward high-performance piezoelectric sensors and energy harvesters Suprapto, Suprapto; jubaidah, Jubaidah; Triono, Selamat; Gunawan, Harianto; Lisyanto, Lisyanto; Nugraha, Aditya Sukma; Aldori, Yopan rahmad
Teknomekanik Vol. 9 No. 1 (2026): Regular Issue
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/teknomekanik.v9i1.44972

Abstract

The piezoelectric efficiency of Poly (vinylidene fluoride) (PVDF) membranes becomes restricted by the challenge of generating and stabilizing electroactive β-phase during processing. Stretching requires control of deformation parameter, while solvent-based methods bring environmental and occupational health risks. This research suggests hot-pressing as an alternative method for enhancing β-phase fraction, utilizing multidirectional stress without solvent or chemical exposure. This study systematically compares uniaxial hot-pressing (Uniaxial HP) and biaxial hot-pressing (Biaxial HP) setups to determine which stress distribution is more effective at promoting changes and improving piezoelectric properties in PVDF membranes. The main objective of this research is to systematically evaluate and compare the impacts of uniaxial and biaxial hot-pressing on the crystalline phase transformation and electromechanical performance, including the piezoelectric coefficient (d33) and output voltage response of PVDF membranes. PVDF pellets were hot-pressed at 220o C under a pressure of 60 MPa for 15 minutes followed by rapid quenching in ice water. X-Ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) confirmed phase composition, correlated with performance via the piezoelectric coefficient (d33), and assessed piezoelectric activity. Experimental results show that biaxial loading provides a higher b-phase fraction (50.47%) compared to untreated membranes (47.80%) and UHP samples (49.30%). The crystallinity and the piezoelectric coefficient also increased to 49% and 18.8 pC/N, respectively. Biaxial stress pattern during hot-pressing induces favourable thermodynamic and kinetic conditions for b-phase expansion. Beyond phase-related results, the approach delivers competitive piezoelectric effectiveness while maintaining simplicity and reducing solvent-dependent processing steps.
Activated Carbon as a Functional and Sustainable Filler in Composite Bipolar Plates For Fuel Cell Applications Iswandi; Suherman; Tino Hermanto; Yopan Rahmad Aldori; Muhammad Idris; Abu Bakar Sulong
Automotive Experiences Vol. 9 No. 1 (2026)
Publisher : Universitas Muhammadiyah Magelang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31603/ae.16009

Abstract

Bipolar plate is a key component that determines a fuel cell's performance and service life. Carbon-based polymer composite materials were developed as lightweight, easy-to-process alternatives to metal. The use of carbon-based fillers in polymer composites has grown rapidly as an alternative to bipolar plate materials in fuel cell applications, especially to meet performance targets set by the U.S. Department of Energy (DOE). DOE requires high electrical conductivity (≥100 S/cm in the in-plane direction and ≥10 S/cm in the through-plane direction), low density, adequate mechanical strength, and good corrosion resistance and chemical stability. Recent studies have shown that the addition of carbon fillers, such as graphite, carbon black, graphene, and activated carbon (AC), can increase electrical conductivity by forming conductive percolation networks in polymer matrices. This study evaluates the potential of AC from household waste in the form of coconut shells as fillers in polypropylene (PP) composites for bipolar plate applications. AC is synthesized through carbonization and activation processes, then mixed into a PP matrix with PP/AC compositions of 100/0, 90/10, 80/20, and 70/30 percent by weight. The focus of the study is the effect of composition variation on density and bending strength. The test results show that increasing the AC fraction tends to decrease the composite density. The maximum density was obtained at a 90/10 (by weight) PP/AC composition of 0.9 g/cm³, indicating more effective filling of the pore matrix by AC particles. On the other hand, bending strength shows a downward trend. The maximum flexural strength is achieved at an AC composition of 34.58 MPa at 10% weight, indicating optimal dispersion and stress transfer between the matrix and the filler. The addition of AC above the composition causes a decrease in bending strength due to potential particle agglomeration, cavities, and the limited mobility of polymer chains. Electrical conductivity tends to increase with the addition of AC due to the formation of a network of electrical currents between carbon particles within cavities, reaching a maximum of 5 S/cm at 30% by weight of AC. The electrical conductivity obtained showed better improvement than several research results on polymeric materials using the hot-press method, with a value of 1.7 S/cm, using graphite filler materials up to 60% by weight. These findings confirm that AC from coconut shells has the potential to serve as a sustainable filler for fuel cell bipolar plates, with an optimal composition that balances density and mechanical properties.
Uniaxial and biaxial hot pressing of PVDF films: A pathway toward high-performance piezoelectric sensors and energy harvesters Suprapto Suprapto; Jubaidah jubaidah; Selamat Triono; Harianto Gunawan; Lisyanto Lisyanto; Aditya Sukma Nugraha; Yopan rahmad Aldori
Teknomekanik Vol. 9 No. 1 (2026): Regular Issue
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/teknomekanik.v9i1.44972

Abstract

The piezoelectric efficiency of Poly (vinylidene fluoride) (PVDF) membranes becomes restricted by the challenge of generating and stabilizing electroactive β-phase during processing. Stretching requires control of deformation parameter, while solvent-based methods bring environmental and occupational health risks. This research suggests hot-pressing as an alternative method for enhancing β-phase fraction, utilizing multidirectional stress without solvent or chemical exposure. This study systematically compares uniaxial hot-pressing (Uniaxial HP) and biaxial hot-pressing (Biaxial HP) setups to determine which stress distribution is more effective at promoting changes and improving piezoelectric properties in PVDF membranes. The main objective of this research is to systematically evaluate and compare the impacts of uniaxial and biaxial hot-pressing on the crystalline phase transformation and electromechanical performance, including the piezoelectric coefficient (d33) and output voltage response of PVDF membranes. PVDF pellets were hot-pressed at 220o C under a pressure of 60 MPa for 15 minutes followed by rapid quenching in ice water. X-Ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) confirmed phase composition, correlated with performance via the piezoelectric coefficient (d33), and assessed piezoelectric activity. Experimental results show that biaxial loading provides a higher b-phase fraction (50.47%) compared to untreated membranes (47.80%) and UHP samples (49.30%). The crystallinity and the piezoelectric coefficient also increased to 49% and 18.8 pC/N, respectively. Biaxial stress pattern during hot-pressing induces favourable thermodynamic and kinetic conditions for b-phase expansion. Beyond phase-related results, the approach delivers competitive piezoelectric effectiveness while maintaining simplicity and reducing solvent-dependent processing steps.
Intensifikasi Produksi Biodiesel dari Minyak Goreng Limbah melalui Teknologi Ultrasonik dengan Optimalisasi Response Surface Methodology Muhammad Idris; Jufrizal Jufrizal; Uun Novalia Harahap; Yopan Rahmad Aldori; Tino Hermanto
IRA Jurnal Teknik Mesin dan Aplikasinya (IRAJTMA) Vol 5 No 1 (2026): April
Publisher : CV. IRA PUBLISHING

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.56862/irajtma.v5i1.301

Abstract

This study aims to optimize biodiesel production from waste cooking oil using ultrasonic technology combined with Response Surface Methodology (RSM). The investigated variables include the methanol-to-oil molar ratio (6–12), alkaline catalyst concentration (1–3 wt%), and ultrasonic reaction time (480–1440 s). Based on 17 experimental runs, a two-factor interaction (2FI) linear regression model was developed. ANOVA results indicate that all variables significantly affect biodiesel yield (p < 0.05), with catalyst concentration as the most influential factor. The model demonstrates high predictive accuracy (R² = 0.937; adjusted R² = 0.900; MAE = 2.24%; RMSE = 2.84%). Optimization results indicate optimal conditions at a methanol-to-oil ratio of 10.96, a catalyst concentration of 1.03 wt%, and a reaction time of 1414.79 s, yielding 96.84% FAME. Ultrasonic technology effectively enhances mixing and accelerates reactions via cavitation. This study provides practical operational guidance to improve the efficiency of sustainable biodiesel production and support carbon emission reduction.
Analisa Tegangan dan Deformasi Pada Desain Kursi Menggunakan Finite Element Method Dengan Variasi Pembebanan Didik Sugiono; Suprapto Suprapto; Yopan Rahmad Aldori; Supardi Supardi
Infotekmesin Vol 16 No 2 (2025): Infotekmesin: Juli 2025
Publisher : P3M Politeknik Negeri Cilacap

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35970/infotekmesin.v16i2.2807

Abstract

The manufacturing process is an activity of processing raw materials into products to increase added value. One of these products is chair furniture; to reduce errors and failures in its manufacture, it is necessary to do prototype model experiments first. This research conducts a simulation study and analysis of the chair design on stress, deformation and safety factor using the Finite Element Method approach with the help of ANSYS ADPL 18.0 static structural software where the chair design is made of 304 stainless steel, aluminum-T6, HCP 30 polymer foam in one chair structure by simulating several static load loading scenarios, boundary conditions, and even distribution on the surface of the chair. The simulation results show that the highest maximum stress distribution (von misses stress) is 3.5 Mpa at a pressure of 175 kg.f, for the lowest value of 1.5 Mpa at a pressure of 5 Kg.f and a deformation (displacement) of 0.145x10ˉ4 mm occurs at a pressure of 175 Kg.f, while the lowest deformation value of 0.621x10ˉ5 occurs at a pressure of 75 Kg.f, This is due to the loading increasing along with the applied pressure force, but still in the minimum safety factor standard position for static loads, so as not to damage the geometric structure.
Analysis of Bending Strength of Composite Materials in Bipolar Plates for Fuel Cell Technology Husri Zarmawan; Iswandi Iswandi; Tino Hermanto; Darianto Darianto; Indra Hermawan; Muhammad Idris; Jufrizal Jufrizal; Yopan Rahmad Aldori
JOURNAL OF ELECTRICAL AND SYSTEM CONTROL ENGINEERING Vol. 9 No. 2 (2026): Journal of Electrical and System Control Engineering
Publisher : Universitas Medan Area

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31289/jesce.v8i2.14227

Abstract

This study aims to this study was to examine the effect of polypropylene (PP) plastic and activated carbon (AC) composition in a plastic composite material. The composite material was mixed using an internal mixer at a processing temperature of 220°C and a speed of 50 rpm. The mixture was then molded with dimensions of 100 mm in length, 15 mm in width, and 2,5 mm in thickness. The sample molding was performed using a compression molding method with a pressure of 1500 MPa at 250°C and a holding time of 300 minutes. Subsequently, the samples were cut according to the bending test dimensions following ASTM D790-03 standards, with dimensions of 100 mm x 12.7 mm x 2.5 mm. The test results for the polypropylene-activated carbon composite in the first composition showed a maximum stress point of 36.95 MPa and an elastic modulus of 4.3096 MPa, while the second composition showed a maximum stress point of 34.58 MPa and an elastic modulus of 3.371 MPa. These findings indicate that increasing the activated carbon composition in polypropylene polymer results in a reduction in bending strength.
Co-Authors Abd Rahman Bin Dullah Abu Bakar Sulong Ade Irma Sagala Aditya Sukma Nugraha Adly Zulqarnain bin Mohamad Andhika Ariyudha Andri Herlambang Ari Handoko Arya Rudi Nasution Aryanta Sembiring, Robi Bagus Suranta Sembiring Bobby Umroh Dadan Ramdan Danial Jack Marbis Sianturi Darianto Darianto Darianto, Darianto Darwin, Felix Derlini Diansyah, Diansyah Didik Sugiono Din Aswan Amran Ritonga Dina Maizana Eka Daryanto, Eka Erni Yusnita Etanto Heiliano Wijayanto Evan Roland Girsang Fadhli Farsa Fahmi Faddillah Fider Lumbanbatu Firmansyah Nasution, Taufik Giovan Panjaitan, Asido Gunawan, Harianto Habib Satria Habib Satria Hadi Pranata Harianto Gunawan HENRY ISKANDAR Hermansyah Hermasnyah Husri Zarmawan Ida Royani INDRA HERMAWAN Indra Hermawan Indri Dayana Iswandi Iswandi Iswandi Iswandi Iswandi Jubaidah jubaidah Jubaidah Jubaidah Jubaidah, Jubaidah Jufrizal Jufrizal JUNAIDI Junaidi Junaidi Listiyanto, Listiyanto Lisyanto . Maghfirah Maghfirah Marwan Marwan Masrajuddin Masrajuddin Mega Puspita Sari Meidiansyah, Fadli Mhd. Iqbal Mhd. Taufik Ardaha Mislan Mislan Moranain Mungkin Muhammad Abdul Rasyid Muhammad Angga Prayoga Muhammad Dava Faruqi Muhammad Idris Muhammad Irwanto Muhammad Yusuf Rahmansyah Siahaan Muhathir, Muhathir Nidya Chitraningrum Nova Arief Setyanto Pangestu, Reno Pratiwi Putri Lestari R. Nurfazriah, Latifah Rambe, Yunita Syafitri Recsi Febian Adiansyah Riana Puspita, Riana Rizki Muliono Ruztamreen Bin Jenal Samsul A Rahman Sidik Hasibuan Sandi Saputra Saufa Yardha Moerni Selamat Riadi Selamat Triono Selamat Triono, Selamat Siswo Pranoto Siti Utari Rahayu Suherman Sukma Aditya Sukmawati Supardi Supardi Suprapto Suprapto Suprapto Suprapto Suprapto Suprapto Suprapto Suprapto Supriatno, Supriatno Syahra, Assyfa Syofyan Anwar Syahputra Syurkarni Ali Taufik Wal Hidayat Theo Fredrik Tumangger Tika Ermita Wulandari Tino Hermanto Uun Novalia Harahap Willyam Warikson Sinaga Yoga Prabowo