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Frekuensi Alat Vibrator Menggunakan Aplikasi BaiFi Dalam Pembuatan Produk Fiberglass Hutasuhut, Asla Tara Roma Ito; Ayu, Putri; Rdiansyah, Sultan Lazua; Yusuf, Dede; Juliani, Rita; Rahmatsyah, Rahmatsyah
CESS (Journal of Computer Engineering, System and Science) Vol 9, No 2 (2024): July 2024
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/cess.v9i2.61040

Abstract

Fiberglass merupakan pengembangan material alternatif pengganti kayu. Keterbatasan sumber daya alam kayu menjadikan fiberglass bernilai ekonomis tinggi dengan berbagai kelebihan yang dimiliki oleh fiberglass yaitu berat yang lebih ringan, lebih tahan terhadap korosi, perawatan lebih mudah. Penjualan pipa fiberglass diseluruh dunia berdasarkan data Verified Market Research diperkirakan meningkat dengan CAGR (Compounded Annual Growth Rate/Tingkat Pertumbuhan per Tahun) sebesar 6,5% dari tahun 2021 hingga 2028. Proses pencetakan produk fiberglass secara manual yang terkadang mengalami kekeliruan pengukuran desain cetakan fiberglass, campuran resin yang tidak merata dan sulitnya membuka produk dari cetakan, dilakukan pembuatan alat vibrator fiberglass yang tersinkronisasi dengan aplikasi BaiFi (Balqis Fiberglass). Tujuan kegiatan adalah menentukan frekuensi getaran yang efektif dalam membuka hasil cetakan produk fiberglass yang dioperasikan melalui aplikasi BaiFi. Metode kegiatan yang dilakukan adalah observasi lapangan, studi literatur, perancangan desain, pembuatan, pengujian, implementasi dan tahap terakhir evaluasi. Pelaksanaan kegiatan yang dilakukan dengan didukung adanya Alat Vibrator Fiberglass dan Aplikasi BaiFi yaitu mampu mempermudah proses dalam melakukan pencetakan produk fiberglass dengan pengukuran desain cetakan fiberglass yang lebih akurat, pengadukan resin yang homogen dan proses pembuka cetakan fiberglass yang lebih mudah dan hasil produk fiberglass yang lebih mulus. Analisis frekuensi getaran yang paling efektif untuk membuka produk fiberglass dari cetakannya berada dalam rentang 30-50 Hz dengan amplitudo dan durasi yang disesuaikan dengan jenis dan ukuran produk. 
Carbon Electrodes from Corn Stalk Core for Supercapacitor Application Juliani, Rita
Journal of Technomaterial Physics Vol. 1 No. 1 (2019): Journal of Technomaterial Physics
Publisher : Talenta Publisher

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32734/jotp.v1i1.825

Abstract

The natural pore structure of corn stalk core potentially contributes as a basic material for activated carbon. The activated carbon from a combination of chemical and physical activation is presented for capacitive energy storage. The chemical activation was carried out using 0.4 M KOH followed by pyrolysis process up to 600°C in an N2 atmosphere. The physical activation was conducted at various temperatures such as 600°C, 700°C, and 800°C with a CO2 gas flow rate of 10 mL/min. Supercapacitor cells were made from carbon electrodes of corn stalk core, 316L stainless steel as the current collector, duck eggshell as the separator, and 1 M H2SO4 as the electrolyte solution. The physical properties of carbon electrodes were characterized by identifying the density, surface morphology and chemical structure of carbon. The density value was obtained based on the mass, thickness, and diameter of the carbon electrode. The lowest density was found at the activation temperature of 700°C which has the potential to produce the best performance in supercapacitor cells. SEM was used to characterize the surface morphology. The activation temperature of 700°C showed the formation of irregular structures and provided large pores for the diffusion of electrolyte ions into the carbon matrix. The FTIR characterization was used to determine the carbon chain elements which formed double layers in supercapacitor cells. The electrochemical properties of supercapacitor cells were tested using cyclic voltammetry. Specific capacitances at the activation temperature of 600°C, 700°C, and 800°C were 90 Fg-1, 108.92 Fg-1, and 44.875 Fg-1, respectively. These results showed that the activation temperature of 700°C was the best temperature in the preparation of supercapacitor electrodes from corn stalk core as the biomass material.
Pembuatan E-Modul Usaha dan Energi Berbasis Pemecahan Masalah Lestari, Rini; Derlina, Derlina; Juliani, Rita; Bukit, Nurdin; Hakim, Abd.; Sahyar, Sahyar
Journal of Management and Bussines (JOMB) Vol 6 No 6 (2024): Journal of Management and Bussines (JOMB)
Publisher : IPM2KPE

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31539/jomb.v6i6.13608

Abstract

This study aims to determine the validity of the design and results of the design of e-modules. problem solving based on business and energy. This study is the creation of electronic modules of business and energy based on problem solving validated by 1 media expert to evaluate the appearance and suitability of the module, then 1 Theory expert to evaluate the depth of the content of the e-module designed by Lecturers at the State University of Medan. The instruments used in this study were questionnaires, media expert validation and material expert questionnaire validation. The results obtained from the aspect of the designed validity of the input of media experts obtained an average score of 88.3% in the very feasible category and for the evaluation of Theory experts the average value was 90.5% in the very feasible category. Based on the results of the study, it was concluded that the e-module of business and energy based on problem solving was valid. Keywords: E-Business Module, Energy, Problem Solving
ANALYSIS OF GRANITE ROCK WEATHERING IN THE PARMONANGAN AREA USING LANDSAT 8 SATELLITE IMAGERY Juliani, Rita; Rahmatsyah, Rahmatsyah; Tampubolon, Togi; Halawa, Erniwati; Sari, Silvia Dona; Purba, Rama Yana
EINSTEIN (e-Journal) Vol. 12 No. 3 (2024): EINSTEIN (e-Journal)
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/eins.v12i3.63264

Abstract

 A research has been conducted to analyze the weathering of granite rocks in the Parmonangan area using Lansat 8 satellite imagery which aims to determine the distribution of rocks, weathering processes, and types of rock forming elements in Parmonangan District, North Tapanuli Regency. The method used is using shp geologic map data and Lansat-8 image data processed using Arcgis Map 10.6.1 to determine the distribution of rocks and land cover. XRF is used to identify compounds and rock-forming elements. The results obtained by the rock distribution of the parmonangan area are in the form of the Kluet Formation, Sibolga Complex and Toba Tuff. Land cover in the parmonagan area has differences from 2016 to 2024. Open land in 2024 has increased and the cloud cover obtained has also increased. The rock elements found are Al2O3 (25.31), SiO2 (24.97), K2O (1.56), TiO2 (0.81), Mn2O (30.66), Fe2O3 (4.66), ZrO2, (0.21), Sb2O3 (0.16), and BaO (0.17).
THE DEVELOPMENT OF HIGHER ORDER THINKING SKILLS (HOTS) TEST INSTRUMENT IN SENIOR HIGH SCHOOL Sinaga, Hari Otta; Juliani, Rita
(IPER) Indonesian Physics Education Research Vol. 3 No. 1 (2022): IPER (Indonesian Physics Education Research )
Publisher : UNIVERSITAS NEGERI MEDAN

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/iper.v3i1.39556

Abstract

The research aims to develop the objective physics instrument test  based Higher Order Thinking skills (HOTS) that already meet the qualification in aspects of validity, reliability, distinguishing power, difficulty level, and effectiveness of detractors. The type of research that is used in research is  Research and Development (R & D), the Borg & Gall models which consists of 7 stages, namely : 1) Research and information collecting, 2) Planning, 3) Development preliminary of products, 4) Preliminary field testing, 5) main product revision, 6) Main Field Test, and 7) Main product revision. Subject of research is student class X in SMA Swasta St. Lusia Sei Rotan who totaled 10 people on the preliminary field testing and student class X in SMA Swasta St.Lusia Sei Rotan and SMA N 2 Percut Sei Tuan who totaled 50 people on the main field testing. Results of the study showed that the validation of the contents by expet judgment is valid with the average value is 87.6 and has been getting evidence empirically through validation construction item test with the average value is 3.9 ( tcalculate > ttable , ttable = 2.01), the reliability of item test is 0.87 with high category ( 𝑟 ≥0,70 ), the distinguishing power have the average value is 0.45 with a category well, the average difficulty level is rather difficult with the range value is 0.2-0.73, and the effectiveness of distractors were function, so that instrument test decent used to measure higher order thinking skills of student.
THE DEVELOPMENT OF E-LKPD BASED ON HIGH-ORDER THINKING SKILLS (HOTS) WITH 4D MODEL Hartono, Jessica Kristanti; Juliani, Rita
(IPER) Indonesian Physics Education Research Vol. 3 No. 2 (2022): IPER (Indonesian Physics Education Research)
Publisher : UNIVERSITAS NEGERI MEDAN

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/iper.v3i2.63122

Abstract

This research aims to know the level of validation and level of practicality of the development of e-LKPD based on HOTS with a 4D model of Doppler effect material from a material expert, media expert, teacher, and student. The research type is a 4D model but this research is limited to 3D steps that are defined, designed, and develop. The research population was students in SMA Negeri 3 Pematangsiantar Class XI Science. The sample research is taken by cluster sampling. In this research, the validators have an instrument with a questionnaire of development e-LKPD to know the level of validation. The instrument of this study was a questionnaire from a material expert, media expert, and teacher. The analysis results that development gets level validation and practicality are very worthy with 92,5% from the material expert, very worthy with 97,5% from the media expert, and very worthy with 95,2% from a teacher. Based on the data, the conclusion is that the development of e-LKPD based on HOTS with a 4D model on the Doppler effect is very worthy of validation and practicality.
The Development of e-Worksheet based on High Order Thinking Skills (HOTS) for Critical Thinking Student Hartono, Jessica Kristanti; Nur'aini M, Rida Sitri; Fauzia, Izza; Juliani, Rita
Jurnal Penelitian & Pengembangan Pendidikan Fisika Vol. 11 No. 2 (2025): JPPPF (Jurnal Penelitian dan Pengembangan Pendidikan Fisika), Volume 11 Issue
Publisher : Program Studi Pendidikan Fisika Universitas Negeri Jakarta, LPPM Universitas Negeri Jakarta, HFI Jakarta, HFI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21009/1.11204

Abstract

This research aims to know the level validation and level practicality of development e-worksheet based on HOTS on doppler effect material from a material expert, media expert, teacher and student. The research type is a 4D model but this research is limited to 3D steps are define, design, and develop due to time and another constraints. The research population was students in SMA Negeri 3 Pematangsiantar Class XI Science. The research population includes trial large group in class XI IPA 1 with 37 students and trial small group with 6 students. The research population has a total of 43 students. The sample research is taken by cluster sampling. In this research, the validators have an instrument with a questionnaire of development e-worksheet to know the level of validation. The instrument of this study was a questionnaire from material expert, media expert, and teacher. The analysis result that development gets level validation and practicality are very worthy with 92,5% from material expert, very worthy with 97,5% from media expert, and very worthy with 95,2% from teacher. Based on the data, the conclusion is that the development of e-worksheet based on HOTS with a 4D model on doppler effect is very worthy of validation and practicality.
Riset Siswa Inovatif Menuju OPSI: Strategi Berbasis Proyek Demi Pendidikan Berkualitas (SDGs 4) Lubis, Rajo Hasim; Sani, Ridwan A; Rahmatsyah; Juliani, Rita; Batubara, Agung Setia
Amal Ilmiah: Jurnal Pengabdian Kepada Masyarakat Vol. 6 No. 3 (2025)
Publisher : FKIP Universitas Halu Oleo

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36709/amalilmiah.v6i3.412

Abstract

Mitra program pengabdian adalah SMAN 18 Medan, sebuah sekolah menengah atas yang memiliki potensi besar dalam mendukung guru untuk memfasilitasi pembelajaran berbasis riset. Namun, hasil observasi menunjukkan bahwa guru masih menghadapi kendala dalam membimbing siswa untuk mengikuti Olimpiade Penelitian Siswa Indonesia (OPSI) secara optimal. Sebagai solusi, program pengabdian akan dilaksanakan melalui serangkaian pelatihan intensif dan pendampingan bagi guru-guru. Target luaran dari program pengabdian adalah meningkatnya kapasitas guru di Sekolah dalam membimbing siswa mengikuti OPSI secara efektif. Melalui kegiatan ini, diharapkan terjadi peningkatan kualitas pembelajaran di Sekolah, sehingga mendukung tercapainya tujuan SDGs Point 4 yakni Pendidikan berkualitas. Metode yang digunakan melibatkan pendekatan partisipatif dengan mengutamakan pelibatan aktif guru dalam setiap tahapan kegiatan. Program pengabdian dimulai dengan identifikasi kebutuhan mitra, pelaksanaan pelatihan dan pendampingan, hingga evaluasi hasil implementasi. Kesimpulan yang diperoleh yakni telah meningkatnya kreativitas guru dalam membimbing OPSI dengan alasan 7 dari 8 tim yang diusulkan telah lolos tahap substansi dan layak melanjutkan penelitian. Pendampingan diharapkan mampu menciptakan perubahan berkelanjutan dalam pola pengajaran guru di Sekolah, sehingga dapat meningkatkan kualitas pendidikan sesuai dengan prinsip SDGs Point 4.
Frekuensi Alat Vibrator Menggunakan Aplikasi BaiFi Dalam Pembuatan Produk Fiberglass Hutasuhut, Asla Tara Roma Ito; Ayu, Putri; Rdiansyah, Sultan Lazua; Yusuf, Dede; Juliani, Rita; Rahmatsyah, Rahmatsyah
CESS (Journal of Computer Engineering, System and Science) Vol. 9 No. 2 (2024): July 2024
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/cess.v9i2.61040

Abstract

Fiberglass merupakan pengembangan material alternatif pengganti kayu. Keterbatasan sumber daya alam kayu menjadikan fiberglass bernilai ekonomis tinggi dengan berbagai kelebihan yang dimiliki oleh fiberglass yaitu berat yang lebih ringan, lebih tahan terhadap korosi, perawatan lebih mudah. Penjualan pipa fiberglass diseluruh dunia berdasarkan data Verified Market Research diperkirakan meningkat dengan CAGR (Compounded Annual Growth Rate/Tingkat Pertumbuhan per Tahun) sebesar 6,5% dari tahun 2021 hingga 2028. Proses pencetakan produk fiberglass secara manual yang terkadang mengalami kekeliruan pengukuran desain cetakan fiberglass, campuran resin yang tidak merata dan sulitnya membuka produk dari cetakan, dilakukan pembuatan alat vibrator fiberglass yang tersinkronisasi dengan aplikasi BaiFi (Balqis Fiberglass). Tujuan kegiatan adalah menentukan frekuensi getaran yang efektif dalam membuka hasil cetakan produk fiberglass yang dioperasikan melalui aplikasi BaiFi. Metode kegiatan yang dilakukan adalah observasi lapangan, studi literatur, perancangan desain, pembuatan, pengujian, implementasi dan tahap terakhir evaluasi. Pelaksanaan kegiatan yang dilakukan dengan didukung adanya Alat Vibrator Fiberglass dan Aplikasi BaiFi yaitu mampu mempermudah proses dalam melakukan pencetakan produk fiberglass dengan pengukuran desain cetakan fiberglass yang lebih akurat, pengadukan resin yang homogen dan proses pembuka cetakan fiberglass yang lebih mudah dan hasil produk fiberglass yang lebih mulus. Analisis frekuensi getaran yang paling efektif untuk membuka produk fiberglass dari cetakannya berada dalam rentang 30-50 Hz dengan amplitudo dan durasi yang disesuaikan dengan jenis dan ukuran produk. 
Analysis of Rare Earth Metal Potential of Parmonangan Area Using X-Ray Fluorescence Juliani, Rita; Rahmatsyah; Tampubolon, Togi; Halawa, Erni; Sari, Silvia Dona; Ismayana; Purba, Rama Yana
Jurnal Penelitian Pendidikan IPA Vol 11 No 5 (2025): May
Publisher : Postgraduate, University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/jppipa.v11i5.10355

Abstract

Rare Earth Elements (REEs) are strategic commodities essential for various high-technology applications, including renewable energy, electronics, and defense systems. However, their uneven global distribution and increasing demand have intensified the need for exploration in undercharacterized regions. This study investigates the REE potential of weathered granitic rocks in the Pamonangan Sub-district, North Sumatra. A total of 200 mesh rock samples from outcrop and subsurface locations were analyzed using X-Ray Fluorescence (XRF) to determine their elemental composition. The geochemical results show high concentrations of SiO₂ and Al₂O₃ relative to Fe₂O₃, suggesting significant weathering of the granitic parent rocks. The combination of elevated SiO₂ and low P₂O₅ contents indicates a predominance of silica-hosted REE phases over phosphate-hosted minerals. Mineralogical analysis confirms the presence of cassiterite, chlorite, monazite, and zircon as secondary REE carriers, particularly of Ce and La. These findings point to a previously unrecognized potential for REE mineralization in the region. This research provides a geochemical and mineralogical framework for future exploration and highlights the importance of weathered granitoids as prospective REE sources in Indonesia.
Co-Authors Abd. Hakim Agus Kembaren Akbar Hasadi Putra S Andil Siregar Andini, Khairanum Ayu, Putri Bara, Agung Setia Batu Batubara, Agung Setia Bintang Lesmana Hutasoit Budiman Nasution Chintya Maretti Pandiangan Cika Faradila Derlina . Derlina Nasution Dian Wardana Dita Trisna Panjaitan Ditya Lufita Edward Relius Laoli Eliyana . Elysabeth Luisa Pakpahan Emelia Ginting Evi Juliani Fachry Abda El Rahman Fatuan Arif Sitorus Fauzia, Izza Febriza, Tiara Rizka Felisa Irawani Hutabarat Fenny Cloudya Damanik Fitri Meliana Friscylia Tampubolon Friscylia Tampubolon Gilang Ma'arif Priatama Halawa, Erni Halawa, Erniwati Halimatun Sakdiah Hana Daforosa R Siagian Harahap, Gusniar Hardianti, Suci Hartono, Jessica Kristanti Hengki Sembiring Hilyati Iftinan Lubis Hutasuhut, Asla Tara Roma Ito Ibnu Akbar Ihdi Shabrona Putri Ilan Nia Lestari Irma Sari Minalta Tarigan Ismayana Isti Ullfa Parinduri Jeksen Kristian Sinaga Jon Berghauser Aritonang Juli Limbong Khoir, Aji Ibnu Kiki Santoso Laili Suryani Laina Miska Laurenchus Manurung Laurenchus Manurung Linda Sari Liza Karina Octovyanda Pohan Lubis, Nur Saimah Makmur Sirait Maria Firma S. Ginting Mariana Simangunsong Mariana Simangunsong Mester Sitepu, Mester Miska, Laina Motlan . Nanda Rahmadani Nur'aini M, Rida Sitri Nurdin Bukit Nurhikmah Weisdiyanti Nurhikmah Weisdiyanti Nurul Qodri Ompusunngu, Yohana D. Purba, Rama Yana Putri Astuti Rahmadani, Nanda Rahmatsyah Rahmatsyah . Rahmatsyah Rahmatsyah, Rahmatsyah Raisa Nabila Rajo Hasim Lubis Rangga Prasetyo Darmawan Rappel Situmorang Rdiansyah, Sultan Lazua Resti Masfidar Waruwu Rini Lestari Rionaldo Tamba Riri Syavira Riri Syavira Riri Syavira Riski Juliandri Tambunan Ruth Fika Ronauli Simbolon Sahyar . Sahyar Sahyar Saima Putrini R. Harahap Sani, Ridwan A Sembiring, Hengki Sigit Irawan Silvia Dona Sari Simanjuntak, Bill Cklinton Simatupang, Rochayanti N. R. Sinaga, Hari Otta Sri Ratika Samosir Sri Ratika Samosir Sulandari Sulandari Sulandari Sulandari Sulandari Sulandari Syahdila, Tiara Tiaminah Nasution Timbangen Sembiring Togi Tampubolon Vebrina Adnin Vianola Elisa Karo Sekali Warmi Hartati Sitanggang Yeni Sipangkar Zahra Tazkia Zulfran Silaban