Article Per Year (5 Year)
p-Index From 2020 - 2025
1.578
P-Index
This Author published in this journals
All Journal AUSTENIT Martabe : Jurnal Pengabdian Kepada Masyarakat Vocatech : Vocational Education and Technology Journal MOTIVECTION : Journal of Mechanical, Electrical and Industrial Engineering Teknika Sains : Jurnal Ilmu Teknik Jurnal Rekayasa, Teknologi, dan Sains Jurnal Masyarakat Madani Indonesia Jurnal Inovatif Mahasiswa Manajemen
Wahyudi, Retno
Unknown Affiliation
Agriculture, Biological Sciences & Forestry Arts Humanities Automotive Engineering Chemical Engineering, Chemistry & Bioengineering Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Economics, Econometrics & Finance Education Electrical & Electronics Engineering Engineering Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mechanical Engineering Public Health Social Sciences Transportation

Published : 10 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 10 Documents
Search

 1 
PERENCANAAN PEMUTAR DONGKRAK ULIR BERKAPASITAS 1 TON Farizal, Farizal; Wahyudi, Retno
TEKNIKA SAINS Vol 4, No 1 (2019): TEKNIKA SAINS
Publisher : Universitas Sang Bumi Ruwa Jurai

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24967/teksis.v4i1.632

Abstract

Dalam kehidupan sehari – hari kegunaan dongkrak sangat penting, terutama saat berkendara, khususnya pada mobil. Dongkrak adalah sebagai alat bantu untuk mengangkat beban kendaraan saat mengalami masalah baik di jalan maupun di bengkel atau rumah. Tetapi dalam menggunakannya, dongkrak masi sedikit sulit, terutama  bagi  wanita,  karna  membutuhkan  tenaga  yang  besar  untuk  memutar pemutar dongkrak, khususnya pada dongkrak ulir . oleh sebab itu dalam tugas akhir ini akan dilakukan modifikasi terhadap meputar dongkrak ulir tersebut. Salah satu cara modifikasinya adalah dengan memberikan roda gigi atau gear box pada pemutar dongkrak, sehingga dapat memudahkan pengguna dalam menggunakan dongkrak dan memutar dongkrak tidak memerlukan tenaga yang tidak terlalu besar, sehingga bisa juga di gunakan oleh pengguna selain laki – laki. Setelah dilakukan modifikasi, maka dilakukan pengujian dari hasil modifikasi tersebut, apakah sesuai dengan yang di inginkan oleh penulis. Dengan memberikan roda gigi pada pemutar dongkrak ulir, maka tenaga untuk memutar tidak terlalu besar,tetapi memang membutuhkan waktu yang lebih sedikit lama di bandingkan dengan sebelum dimodifikasi, yaitu pemutar dongkrak tanpa adanya roda gigi.
PENGUJIAN PROGRAM PREDIKSI KECEPATAN POROS ROTOR BERTINGKAT SECARA EKSPERIMENTAL Sembiring, Alexander; Lubis, Asnawi; Wahyudi, Retno
AUSTENIT Vol. 16 No. 2 (2024): AUSTENIT: October 2024
Publisher : Politeknik Negeri Sriwijaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.53893/austenit.v16i2.8513

Abstract

In the process of designing a rotor shaft system, there are aspects that need to be considered to produce a well-functioning rotor shaft system when it starts operating. Failures that occur in rotor shaft systems are generally caused by excessive vibrations in the system. This can be avoided by detecting the system's natural frequencies early on, as predicting its natural frequencies can also predict its critical rotational speeds. The critical rotational speeds of the system can be determined by solving its equations of motion using various methods. In this study, the equations of motion of the system were solved using the finite element method, where local matrix equations were determined according to the equations and then global matrix equations were obtained and solved using a direct method, employing the eigenvalues and eigenvectors of the system. A program was designed to predict the critical rotational speeds of the system. The program was implemented using the MATLAB programming language. The results of the program, when compared with laboratory test results, showed a difference of 1.23%-3.69%.
Design of Hole Digging Machine for Papaya Planting Preparation Sembiring, Alexander; Wahyudi, Retno
MOTIVECTION : Journal of Mechanical, Electrical and Industrial Engineering Vol 6 No 2 (2024): Motivection : Journal of Mechanical, Electrical and Industrial Engineering
Publisher : Indonesian Mechanical Electrical and Industrial Research Society (IMEIRS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.46574/motivection.v6i2.330

Abstract

The agricultural production process heavily relies on land preparation, which significantly impacts the outcomes. Optimal land preparation is the initial step towards achieving maximum yields. Digging planting holes provides suitable growth spaces, eliminates weeds, and improves soil physical properties. Currently, hole digging processes are predominantly done manually (using hoes, manual augers), which are inefficient, time-consuming, and result in uneven holes. Through this research, a machine was designed to swiftly and uniformly dig planting holes to support pepaya growth. The machine utilizes a Honda GX-120 gasoline engine with a maximum power of 2.6 kW at 3,600 rpm to drive a gearbox connected to a soil drilling shaft made of 1.25-inch-thick iron pipe with a 3.2 mm thickness and equipped with 4 mm thick iron screw blades. These machine components are integrated into a mainframe with wheels for ease of movement during the hole digging process. Proses produksi pertanian sangat bergantung pada persiapan lahan, yang akan mempengaruhi hasil yang didapatkan. Persiapan lahan yang optimal merupakan langkah awal untuk mendapatkan hasil yang maksimal. Pembuatan lubang tanam dapat menyediakan tempat tumbuh yang sesuai untuk pertumbuhan, membasmi tumbuh-tumbuhan penggangu, dan memperbaiki sifat-sifat fisik tanah. Saat ini proses pelubangan tanam masih banyak dilakukan secara tradisional (menggunakan cangkul, ulir manual) yang tidak terlalu efektif dan membuuthkan waktu yang lama untuk melakukan proses pelubangan tanam, dan menghasilkan lubang tanam yang tidak seragam. Melalui peneilitian ini dirancang sebuah mesin yang dapat membuat lubang tanam secara cepat, dan seragam yang akan mendukung proses pertumbuhan pepaya. Hasil yang dirancang menggunakan mesin penggerak motor bensin Honda GX-120 dengan daya maksimal 2,6 kW pada putaran 3.600 rpm untuk menggerakkan gearbox yang terhubung dengan poros pengebor tanah dari pipa besi berukuran 1,25 inch dengan ketebalan 3,2 mm dan terdapat daun screw besi dengan ketebalan 4 mm. Elemen-elemen mesin ini disatukan dalam sebuah rangka utama yang terdapat roda, sehingga dapat mempermudah pergerakan mesin ini dalam proses pelubangan tanam.
Designing of Machine to Make Sectional Flight Screw Wahyudi, Retno; Sembiring, Alexander
MOTIVECTION : Journal of Mechanical, Electrical and Industrial Engineering Vol 6 No 2 (2024): Motivection : Journal of Mechanical, Electrical and Industrial Engineering
Publisher : Indonesian Mechanical Electrical and Industrial Research Society (IMEIRS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.46574/motivection.v6i2.331

Abstract

An Auger resembles a large Screw, but its blades are designed to lift and move material, rather than fasten it like a Screw. The primary function of an Auger is to bore holes by rotating and using its blades to cut and extract material, thus clearing the hole. Manual leaf processing remains a common practice in many areas, which is time-consuming and labor-intensive, often resulting in inconsistent product quality. This process is inefficient and incurs high operational costs, reducing profits for farmers and small industries. This research aims to design and develop a leaf-making machine with a sectional Flight Screw type. The methodology includes literature review, prototype design and development, performance testing, and data analysis. The machine has dimensions of 63 x 21.5 x 57.5 cm, using materials such as 4x4 cm angle iron, 5 mm thick IWF iron, and 15 mm thick plate iron. The semi-mechanical Screw leaf-making machine has a maximum pitch length of 165 mm, a maximum Screw diameter of 360 mm, a maximum thickness of 10 mm, and a maximum torque of 3.5 kg.m, producing high uniformity among the Screw leaves made by the semi-mechanical Auger machine. Auger menyerupai sekrup besar, namun bilahnya dirancang untuk mengangkat dan memindahkan material, bukan mengencangkan. Fungsi utama Auger adalah mengebor lubang dengan memutar dan menarik material keluar. Pengolahan daun secara manual masih umum di banyak daerah, memakan waktu dan tenaga serta menghasilkan produk berkualitas tidak konsisten. Proses ini tidak efisien dan memerlukan biaya operasional tinggi, mengurangi keuntungan petani dan industri kecil. Penelitian ini bertujuan merancang dan mengembangkan mesin pembuat daun tipe Screw sectional Flight. Metodologi mencakup studi literatur, desain dan pengembangan prototipe, pengujian kinerja, serta analisis data. Mesin memiliki dimensi 63 x 21,5 x 57,5 cm, dengan bahan besi siku 4x4 cm, besi iwf tebal 5 mm, dan besi plat tebal 15 mm. Mesin semi mekanis ini memiliki kapasitas maksimal panjang pitch 165 mm, diameter daun Screw 360 mm, tebal 10 mm, torsi 3,5 kg.m, dan menghasilkan keseragaman tinggi.
Optimizing MATLAB Applications to Advance Automotive System Development Ibrahim, Fauzi; Hadi, Agung Efriyo; Marjuni, Teuku; Apriyanto, Agus; Putri, Novia Utami; Wahyudi, Retno; Sembiring, Alexander; Murti, Adam Wisnu
Jurnal Rekayasa Teknologi dan sains Vol 9, No 2 (2025): Jurnal Rekayasa, Teknologi, dan Sains
Publisher : Fakultas Teknik Universitas Malahayati

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33024/jrets.v9i2.21385

Abstract

The automotive industry continues to evolve with the integration of sophisticated computational tools to optimize design, analysis, and control systems. MATLAB, known for its powerful numerical and simulation capabilities, has emerged as a key tool in achieving efficiency, accuracy, and automation across automotive engineering processes. This study explores the strategic utilization of MATLAB in areas such as engine modeling, vehicle dynamics simulation, embedded system development, and control system design. The research employs a qualitative method supported by case studies from various industrial applications, highlighting how MATLAB toolboxes like Simulink, Stateflow, and Simscape contribute to reducing development time and improving system performance. Results show that optimized MATLAB use not only accelerates prototyping and testing phases but also enhances precision in control strategies, especially for electric and autonomous vehicles. This paper concludes by emphasizing the growing importance of MATLAB proficiency among automotive engineers and its role in driving digital transformation in the industry. 
Analysis of Thermal Efficiency of the Honda GK5 Engine Fueled with Young Coconut Waste Bioethanol Using a Thermodynamic Approach Wahyudi, Retno; Ibrahim, Fauzi; Sembiring, Alexander; Apriyanto, Agus; Murti, Adam Wisnu; Putri, Novia Utami
VOCATECH: Vocational Education and Technology Journal Vol 7, No 1 (2025): August
Publisher : Akademi Komunitas Negeri Aceh Barat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.38038/vocatech.v7i1.214

Abstract

The global energy crisis and increasing awareness of the negative environmental impacts of fossil fuels have driven the development of sustainable alternative energy sources. One promising renewable fuel is bioethanol, especially when produced from agricultural waste such as young coconut waste. This study aims to evaluate the effect of using bioethanol derived from young coconut waste on the thermal efficiency of the Honda GK5 engine through thermodynamic analysis based on the Otto cycle model and verification using experimental data. The research method includes laboratory testing of the Honda GK5 engine with variations in fuel mixtures: E0, E10, E20, and E30. The test results show a significant increase in thermal efficiency up to the E20 mixture, with an experimental efficiency of 31.8% and a theoretical efficiency of 32.0%. This improvement is attributed to the high octane number of bioethanol, which supports more complete combustion. However, at the E30 mixture, a decrease in efficiency is observed due to the lower heating value of bioethanol. The Otto cycle model successfully represents the trend of thermal efficiency with an average deviation of 1–1.5% compared to experimental results. Therefore, bioethanol from young coconut waste proves not only to be environmentally friendly but also capable of enhancing engine energy performance optimally without requiring significant modifications.
PENERAPAN TEKNOLOGI MELALUI TRAINER KIT ENERGI BARU TERBARUKAN DI SMKN 1 MERBAU MATARAM, LAMPUNG SELATAN Utami Putri, Novia; Jafar Adrian, Qadhli; Febrian, Angga; Rizki Dalimunthe, Ernando; Wahyudi, Retno; Sembiring, Alexander; Edi Rosandi, Aditya
Martabe : Jurnal Pengabdian Kepada Masyarakat Vol 8, No 7 (2025): MARTABE : JURNAL PENGABDIAN KEPADA MASYARAKAT
Publisher : Universitas Muhammadiyah Tapanuli Selatan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31604/jpm.v8i7.2934-2940

Abstract

Penerapan teknologi melalui Trainer Kit EBT sebagai sumber energi terbarukan semakin penting dalam mengatasi krisis energi dan perubahan iklim global. Artikel ini membahas penerapan teknologi sebuah trainer kit ini dirancang sebagai media pembelajaran untuk meningkatkan pemahaman teknis dan keterampilan praktis dalam pemasangan, pengoperasian, dan pemeliharaan sistem tenaga surya di SMK Negeri 1 Merbau Mataram. Trainer kit ini mencakup modul-modul praktis yang meliputi instalasi panel surya, sistem penyimpanan energi, dan konfigurasi inverter, serta simulasi masalah nyata yang sering terjadi dalam implementasi PLTS.
REVIEW ON TITANIUM-BASED ALLOYS AS BIOMATERIALS FOR IMPLANT APPLICATIONS Prastyo, Adi; Ibrahim, Fauzi; Efriyo Hadi, Agung; Febrina, Rina; Winarno, Rudi; Ermasari, Anissa; Wahyudi, Retno
Jurnal Rekayasa Teknologi dan sains Vol 7, No 1 (2023): Jurnal Rekayasa, Teknologi, dan Sains
Publisher : Fakultas Teknik Universitas Malahayati

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33024/jrets.v7i1.8762

Abstract

ABSTRACT Technological updates in the field of advanced materials research now tend to focus on biomedical materials application and utilization of Titanium and its alloys. Various of implant materials have been employed in various disciplines of medical science depending on the requirements of a particular application. Metals, alloys, ceramics, and polymers are the commonly used biomaterials. Titanium and its alloys are commonly used in almost all disciplines of medicine because of their sufficient biocompatibility and meeting of mechanical requirements. The main focus of this study is to review the various structural and microstructural properties of titanium and titanium-based alloys used as orthopedic implants. Orthopedic implants need to possess certain important qualities to ensure their safe and effective use. These properties like the biocompatibility, relevant mechanical properties, high corrosion and wear resistance and osseointegration are summarized in this review. Various attempts to improve upon these properties like different processing routes, surface modifications have also been inculcated in the paper to provide an insight into the extent of research and benefit that has been put into developing a highly superior titanium orthopedic implant. In addition, this paper also discusses in detail the various surface modification techniques to achieve superior biocompatibility, higher wear and corrosion resistance. Overall, an attempt has been made to bring out the current scenario of Ti based materials for biomedical applications. Keywords: titanium, implant, biomaterial.
Pengolahan Pakan Ternak Berkualitas dengan Mesin Mix-Chop Portable di Pekon Mataram Kecamatan Gading Rejo Kabupaten Pringsewu Natalina, Natalina; Ibrahim, Fauzi; Ergantara, Rani Ismiarti Ergantara; Wahyudi, Retno; Apriyanto, Agus; Putri, Novia Utami Putri; Sembiring, Alexander; Murti, Adam Wisnu
Jurnal Masyarakat Madani Indonesia Vol. 4 No. 4 (2025): November
Publisher : Alesha Media Digital

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.59025/5h21q179

Abstract

Pekon Mataram di Kecamatan Gading Rejo, Kabupaten Pringsewu, Provinsi Lampung memiliki potensi besar di bidang pertanian dan peternakan, namun masih menghadapi keterbatasan dalam penyediaan pakan ternak berkualitas. Selama ini, peternak mengandalkan rumput liar yang tersedia melimpah, tetapi pemanfaatannya belum optimal karena proses pengolahan yang masih tradisional sehingga nilai gizi dan efisiensi pemakaiannya rendah. Untuk mengatasi permasalahan tersebut, kegiatan pemberdayaan masyarakat dilakukan melalui penerapan mesin mix-chop portable yang mampu mencacah dan mencampur rumput dengan bahan tambahan bergizi, disertai pelatihan pembuatan pakan fermentasi serta manajemen pemeliharaan ternak. Tujuan kegiatan ini adalah meningkatkan kualitas dan kuantitas pakan, memperbaiki manajemen usaha peternakan, serta memperluas akses pemasaran hasil ternak. Metode pelaksanaan meliputi sosialisasi, pelatihan, penerapan teknologi, pendampingan, dan evaluasi yang melibatkan partisipasi aktif peternak. Hasil kegiatan menunjukkan adanya peningkatan keterampilan peternak dalam mengolah pakan, efisiensi waktu dan tenaga, serta terbentuknya kelompok usaha bersama yang mendukung keberlanjutan program. Hasil kegiatan menunjukkan adanya peningkatan keterampilan peternak dalam mengolah pakan sebesar 80%, peningkatan efisiensi produksi hingga 50%, serta kenaikan rata-rata bobot ternak sapi sebesar 18%. Sebanyak 20 peserta pelatihan berhasil mengoperasikan mesin mix-chop dan memproduksi pakan fermentasi secara mandiri.
PENGARUH LOAN TO DEPOSIT RATIO DAN NONPERFORMING LOAN TERHADAP RETURN ON ASSETS PADA BANK KATEGORI KBMI 3 YANG TERDAFTAR DI BURSA EFEK INDONESIA PERIODE 2021 Wahyudi, Retno; Wibowo, Dedi
Jurnal Inovatif Mahasiswa Manajemen Vol 3 No 1 (2022): Jurnal Inovatif Mahasiswa Manajemen
Publisher : Feb Universitas Dirgantara Marsekal Suryadarma

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35968/

Abstract

Penelitian ini bertujuan untuk mengetahui pengaruh Loan to Deposit Ratio (LDR) dan Non Performing Loan (NPL) terhadap Return On Assets (ROA) secara parsial dan simultan pada Bank kategori KBMI 3 yang terdaftar di BEI tahun 2021. Metode sampel menggunakan purposive sampling. Sampel yang digunakan dalam penelitian ini sebanyak 40 data laporan keuangan dari 10 bank. Jenis data dalam penelitian ini adalah data kuantitatif berupa data sekunder yaitu laporan keuangan perusahaan, data LDR, NPL, dan ROA pada tahun 2021. Data didapat dengan mengakses website pada setiap bank, Bursa Efek Indonesia (www.idx.co.id) dan Otoritas Jasa Keuangan (www.ojk.co.id). Metode analisis data menggunakan deskriptif kuantitatif dengan analisis statistik. Data diolah dengan software SPSS versi 25. Hasil penelitian secara parsial menunjukkan bahwa LDR berpengaruh negatif dan signifikan terhadap ROA. NPL berpengaruh negatif dan signifikan terhadap ROA. Hasil penelitian secara simultan menunjukkan bahwa LDR dan NPL berpengaruh signifikan terhadap ROA. Nilai koefisien determinasi adalah 65,4% sedangkan sisanya dipengaruhi variabel lain.
Co-Authors Alexander Sembiring Apriyanto, Agus Asnawi Lubis Edi Rosandi, Aditya Efriyo Hadi, Agung Ergantara, Rani Ismiarti Ergantara Ermasari, Anissa Farizal Farizal FEBRIAN, ANGGA Hadi, Agung Efriyo Ibrahim, Fauzi Marjuni, Teuku Murti, Adam Wisnu Natalina Natalina Novia Utami Putri Prastyo, Adi Putri, Novia Utami Putri Qadhli Jafar Adrian Rina Febrina, Rina Rizki Dalimunthe, Ernando Sembiring, Alexander Utami Putri, Novia Wibowo, Dedi Winarno, Rudi