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All Journal Indonesian Journal of Geography Jurnal Penelitian Fisika dan Aplikasinya (JPFA) Jurnal Infinity Tadris: Jurnal keguruan dan Ilmu Tarbiyah Progresiva : Jurnal Pemikiran dan Pendidikan Islam Jurnal Optimasi Sistem Industri JURNAL ILMIAH PENDIDIKAN FISIKA AL BIRUNI Forum Geografi Jurnal Penelitian dan Pembelajaran IPA Indonesian Journal of Science and Technology Journal of Natural Sciences and Mathematics Research Al-Jabar : Jurnal Pendidikan Matematika JIPF (Jurnal Ilmu Pendidikan Fisika) PRISMA Journal of Islamic Architecture Desimal: Jurnal Matematika Jurnal Pertahanan : Media Informasi tentang Kajian dan Strategi Pertahanan yang Mengedepankan Identity, Nasionalism dan Integrity JTAM (Jurnal Teori dan Aplikasi Matematika) International Journal of Supply Chain Management Navigation Physics : Journal of Physics Education Andalasian International Journal of Agricultural and Natural Sciences International Journal of Electronics and Communications Systems International Journal of Hydrological and Environmental for Sustainability Journal of Advanced Sciences and Mathematics Education Online Learning in Educational Research Islamic Journal of Integrated Science Education JIPI (Jurnal IPA dan Pembelajaran IPA) Jurnal Infinity
Rofiqul Umam
School Of Science And Technology, Kwansei Gakuin University, Japan
Religion Agriculture, Biological Sciences & Forestry Arts Humanities Astronomy Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Decision Sciences, Operations Research & Management Earth & Planetary Sciences Education Electrical & Electronics Engineering Engineering Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mathematics Mechanical Engineering Physics Social Sciences Transportation Other

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Identification of the Subsurface Structure of Geothermal Working Area of the Hamiding Mountain, North Maluku through Land Surface Temperature (LST) Data and Forward Modeling with the Gravity Method Muhammad Nafian; Belista Gunawan; Nanda Ridki Permana; Rofiqul Umam
Journal of Natural Sciences and Mathematics Research Vol 8, No 1 (2022): June
Publisher : Faculty of Science and Technology, Universitas Islam Negeri Walisongo Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21580/jnsmr.2022.8.1.11902

Abstract

The Mount Hamiding area has one of the largest geothermal potentials in Indonesia to be exploited. Therefore, this research was conducted with the aim of knowing the subsurface structure in the area using the gravity method. To correlate gravity data in order to obtain parameters to measure the increase in surface temperature using supporting data is land surface temperature. Derivative analysis and 2D modeling carried out by forward modeling is one method that can strengthen the geothermal potential in the area. Based on the Land Surface Temperature map, the temperature around the geothermal prospect area is 22 – 25 0C. The results of the derivative analysis show that the geothermal prospect of Mount Hamiding is controlled by two different faults, a fault due to the depression of the old Hamiding caldera and a local fault under the surface of Mount Dukono, which is confirmed as a reverse fault. While the 2D modeling identified the geothermal reservoir layer, which is estimated to have a density of 1.59 gr/cc and consists of a mixture of tuff and minor lava, where the contents of this reservoir are water dominant due to the relatively low-density value with a depth of -411 – (-1280) m, above the reservoir layer it is suspected that the tuff and clay insert layer has a density of 2.56 gr/cc with a depth of 310 – (-1280) m, and the covering layer which is presumed to be a clay cap layer has a density of 1.39 gr/cc with a depth of 870 – (-620). ©2022 JNSMR UIN Walisongo. All rights reserved.
Relationship between Organizational Learning and Supply Chain Agility on Organizational Performance: A Quantitative Study in Fashion SMEs Parama Kartika Dewa; Irma Nur Afiah; Rofiqul Umam
Jurnal Optimasi Sistem Industri Vol. 23 No. 1 (2024): Published in July 2024
Publisher : The Industrial Engineering Department of Engineering Faculty at Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/josi.v23.n1.p46-60.2024

Abstract

Supply Chain Agility (SCA) is recognized as a crucial component in fostering organizational agility, offering a competitive and expansionary strategy for businesses. However, the impact of SCA on organizational performance, particularly in the fashion industry, remains underexplored. This study aims to investigate how learning and agility within the supply chain affect the performance of fashion SMEs, providing a comprehensive understanding of these dynamics. Employing a quantitative approach, data were collected through a questionnaire from 180 fashion SMEs in the Special Region of Yogyakarta, with responses obtained from managers in the fashion industry sector. This methodological choice ensures that the insights gathered are both relevant and specific to the targeted industry. A Structural Equation Modeling using Partial Least Squares (SEM-PLS) was utilized to test the hypotheses, focusing on both the direct and indirect effects of internal and external learning dimensions on organizational performance. The findings reveal that both learning and supply chain agility significantly enhance the performance of fashion SMEs, underscoring their importance in boosting organizational effectiveness. Specifically, the study highlights that internal learning processes and external knowledge acquisition are both critical in fostering a more agile and responsive supply chain. These results contribute to the understanding of how SMEs in the fashion sector can leverage learning and agility to improve performance, supporting the development of more effective supply chain strategies. Consequently, the study's hypotheses are validated, providing valuable insights for practitioners and researchers in the field. This research underscores the potential for fashion SMEs to enhance their competitive edge and operational efficiency through strategic learning and agile supply chain management.
Mathematical representation: A bibliometric mapping of the research literature (2013–2022) Putra, Fredi Ganda; Lengkana, Dewi; Sutiarso, Sugeng; Nurhanurawati, Nurhanurawati; Saregar, Antomi; Diani, Rahma; Widyawati, Santi; Suparman, Suparman; Imama, Khoirunnisa; Umam, Rofiqul
Jurnal Infinity Vol 13 No 1 (2024): VOLUME 13, NUMBER 1, INFINITY
Publisher : IKIP Siliwangi and I-MES

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22460/infinity.v13i1.p1-26

Abstract

Mathematical representation ability is an essential skill for students to understand mathematical concepts. Many studies have been conducted regarding this ability, but it is necessary to map existing research to provide a clearer picture of future research topics. This study aims to provide a bibliometric review of trends using mathematical representation skills in mathematics teaching research. The method in this study is bibliometric analysis, which aims to analyze and classify bibliographic material by presenting representative summaries of the literature in the Scopus database. The search was carried out using the keyword "mathematical representation" and selecting "article title" in the search menu in the Scopus.com database. Perish or Publish (PoP) software analyzes the author's name, number of document citations, document title, year of publication, document source, publisher, and document type. The results showed 99 publications and 357 citations related to mathematical representations, where the number of publications and citations fluctuated. The application of learning models and approaches, computer media, and analysis of mathematical representations is a research trend related to this variable. Therefore, paying attention to mathematical representations in learning mathematics and using effective strategies to improve students' mathematical representation abilities is essential. The findings of this study indicate the need to develop syntax and learning media based on mathematical representations to strengthen students' mathematical abilities.
Physics Learning through Active Learning Based Interactive Conceptual Instructions (ALBICI) to Improve Critical Thinking Ability Diani, Rahma; Irwandani, Irwandani; Al-Hijrah, Al-Hijrah; Yetri, Yetri; Fujiani, Dwi; Hartati, Niken Sri; Umam, Rofiqul
Jurnal Penelitian dan Pembelajaran IPA Vol 5, No 1 (2019): Available Online in May 2019 (Web of Science Indexed)
Publisher : Department of Science Education, Universitas Sultan Ageng Tirtayasa

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30870/jppi.v5i1.3469

Abstract

The process of physics learning in MAN (Islamic senior high school) 2 Bandar Lampung which is still teacher-centered causes students to have low critical thinking skills. One learning model that can be used to overcome this problem is the Active Learning Based Interactive Conceptual Instructions (ALBICI) model which is equipped with Predict, Discuss, Explain, Observe, Discuss, Explore, Explain Tasks (PDEODE*E tasks). The purpose of this study is to determine the effectiveness of the ALBICI model with PDEODE*E tasks in improving students’ critical thinking skills on momentum and impulses subject material. The type of research used is quasi-experimental with 30 students of the class X1 as the experimental class and 30 students of class X2 as the control class. The results of data analysis using t-test at a significance level of 0.05 indicate that the ALBICI model with PDEODE*E tasks iseffective in improving students’ critical thinking skills. Furthermore, theobtainedeffect size of 0.6 indicates that the model's effectiveness falls into the medium category.
Innovative Leadership Management: The Pattern of School Quality Development at SMP Muhammadiyah 2 Inovasi Malang Ridwanulloh, M. Ubaidillah; Huda, Syamsul; Umam, Rofiqul
Progresiva : Jurnal Pemikiran dan Pendidikan Islam Vol. 11 No. 01 (2022): January-June
Publisher : Universitas Muhammadiyah Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22219/progresiva.v11i01.20742

Abstract

This study aimed to examine innovative school leadership management in order to improve school quality. Innovation strategies in the aspects of school leadership include the promotion of the work ethic of human resources, implementation of the curriculum, learning methods and media, and school facilities and infrastructure. This research was conducted by direct field observation at SMP Muhammadiyah 2 Inovasi, Malang, thus involving in depth interview and repeated observations. This research applied qualitative approach with descriptive analysis to describe the object of study comprehensively. The results showed that school management based on innovation as a strategy to improve school quality had proven successful. In the end, the school experienced an increase in the number of enrolled students, academic and non-academic achievements. Moreover, the number of graduates who continued to a higher level was doubled.
Mathematical representation: A bibliometric mapping of the research literature (2013–2022) Fredi Ganda Putra; Dewi Lengkana; Sugeng Sutiarso; Nurhanurawati Nurhanurawati; Antomi Saregar; Rahma Diani; Santi Widyawati; Suparman Suparman; Khoirunnisa Imama; Rofiqul Umam
Jurnal Infinity Vol 13 No 1 (2024): VOLUME 13, NUMBER 1, INFINITY
Publisher : IKIP Siliwangi and I-MES

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22460/infinity.v13i1.p1-26

Abstract

Mathematical representation ability is an essential skill for students to understand mathematical concepts. Many studies have been conducted regarding this ability, but it is necessary to map existing research to provide a clearer picture of future research topics. This study aims to provide a bibliometric review of trends using mathematical representation skills in mathematics teaching research. The method in this study is bibliometric analysis, which aims to analyze and classify bibliographic material by presenting representative summaries of the literature in the Scopus database. The search was carried out using the keyword "mathematical representation" and selecting "article title" in the search menu in the Scopus.com database. Perish or Publish (PoP) software analyzes the author's name, number of document citations, document title, year of publication, document source, publisher, and document type. The results showed 99 publications and 357 citations related to mathematical representations, where the number of publications and citations fluctuated. The application of learning models and approaches, computer media, and analysis of mathematical representations is a research trend related to this variable. Therefore, paying attention to mathematical representations in learning mathematics and using effective strategies to improve students' mathematical representation abilities is essential. The findings of this study indicate the need to develop syntax and learning media based on mathematical representations to strengthen students' mathematical abilities.
Development and Optimization of Polyethersulfone-Zeolite Mix Matrix Membrane Using Rice Husk Ash for Cadmium Removal in Landfill Leachate Riana, Ulfa; Saiful*, Saiful; Ramli, Muliadi; Rashidi Abdull Manap, Mohd; Umam, Rofiqul
Jurnal IPA & Pembelajaran IPA Vol 9, No 1 (2025): MARCH 2025
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jipi.v9i1.42605

Abstract

Increasing the volume of waste at the final disposal site will contribute to environmental pollution due to the seepage of leachate resulting from the waste decomposition process. Leachate is dangerous and toxic because it contains bacteria, organics or inorganic compounds, and heavy metals like cadmium (Cd). Therefore, methods for reducing Cd levels continue to be developed using a mixed matrix membrane. This research used the silica content from rice husk ash as a precursor for zeolite synthesis. The zeolite is then used as a filler to make politersufon-zeolite mixed matrix membrane (PES-zeolite MMM), which is applied to reduce Cd levels in leachate. The synthesized zeolite is a white solid that is similar to Na-A zeolite. The resulting PES-zeolite MMM showed better mechanical properties than the pure PES membrane. MMM has a tensile strength of 20.31 kgf/mm2, elongation of 105.5%, degree of expansion of 33.89%, porosity of 22.85%, and flux of 118.52 L/m2 hours. The optimum performance of PES-zeolite MMM in adsorption of Cd ions was obtained at a loading percentage of 40% and 30 minutes is the best contact period. The adsorption capacity of Cd ions is 2.27 mg/g. The adsorption isotherm model follows the Langmuir isotherm model with a correlation coefficient (R2) of 0.9152 and Qm of 3.35 mg/g. PES-zeolite MMM 40% can be regenerated using NaCl and HCl solutions, with the maximum adsorption capacity for each solution being 1.99 mg/g and 1.75 mg/g. Applying PES-zeolite MMM in leachate samples reduced Cd and Hg ions levels and several other leachate parameters
An unsupervised machine learning algorithm approach using K-Means Clustering for optimizing Surface Wave Filtering in seismic reflection data Hartono Hartono; Haerul Anwar; Rofiqul Umam; Hirotaka Takahashi
Journal of Natural Sciences and Mathematics Research Vol. 10 No. 1 (2024): June
Publisher : Faculty of Science and Technology, Universitas Islam Negeri Walisongo Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21580/jnsmr.v10i1.22399

Abstract

Surface waves often cause significant noise in seismic data, complicating the interpretation of subsurface structures. Traditional filtering methods, such as FK filtering, usually struggle with non-stationary noise and require extensive manual parameter tuning. This study explores the effectiveness of using K-means clustering, incorporating attributes such as amplitude, frequency, and phase to filter surface waves from seismic data. Synthetic seismic data were first generated to test the proposed method, ensuring its robustness before application to real field data. Attributes were extracted from each seismic trace, including instantaneous amplitude, frequency, and phase. These attributes were used as input parameters for the K-means clustering algorithm. The identified clusters corresponding to surface waves were then used to filter these waves from the seismic data. The K-Means clustering effectively differentiated surface waves from reflected waves in both synthetic and real seismic datasets. The method demonstrated that by including phase as an attribute, alongside amplitude and frequency, the accuracy of surface wave detection and filtering significantly improved. The synthetic data showed a clear separation of wave types, validating the method. When applied to real field data, the approach consistently removed surface waves, clarity of seismic reflections crucial for subsurface analysis.
Magnetic data analysis using 2D inversion: A case study from Terak Radiogenic Geothermal area, Bangka Island, Indonesia Siregar, Rahmat Nawi; Rohim, Miftahul; Permanasari, Ikah Ning Prasetiowati; Puspitarum, Deska Lismawenning; Umam, Rofiqul
Navigation Physics : Journal of Physics Education Vol 7, No 1 (2025): Navigation Physics : Journal of Physics Education Vol. 7 No. 1 Tahun 2025
Publisher : UNIVERSITAS INDRAPRASTA PGRI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30998/npjpe.v7i1.4111

Abstract

The presence of geothermal manifestation such as Terak hot spring near granite massive bodies on Bangka Island raises an importatnt question about the subsurface characteristics of a potential radiogenic system. As traditional geothermal system in Indonesia is well known, research must now focus on understanding the radiogenic system, especially on the subsurface information. This study addresses the local magnetic susceptibility of Terak subsurface hot spring by performing magnetic method. The integration of 2D to 3D magnetic data, field observations and geological information show high susceptibility data (>0.005 SI) which are indicated as granite intrusion which act as the heat source. A central zone of lower susceptibility (<0.005 SI) displays a distinct pattern, interpreted as a fracture zone as the hydrothermal fluid pathways. The identification of recharge area further supports the interpretation of an active hydrothermal system. The result of this study are in good agreement with the geological framework of the region and contribute to a better understanding of radiogenic geothermal systems in Indonesia.
MACRONUTRIENT CONTENT OF DRY LEAVES COMPOST BY VERMICOMPOSTING METHOD Kasam, Kasam; Iresha, Fajri Mulya; Adytama, Alhamdy; Mutolib, Abdul; Umam, Rofiqul; Rasdiana, Felga Zulfia; Rahmat, Ali
Andalasian International Journal of Agriculture and Natural Sciences (AIJANS) Vol. 1 No. 01 (2020)
Publisher : Lembaga Penelitian dan Pengabdian, Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (166.082 KB) | DOI: 10.25077/aijans.v1.i01.1-8.2020

Abstract

Waste management is one of the criteria for the evaluation of Green campus and sustainable university. Organic waste takes place in concern because of the domination of waste in university, such as food waste and dry leaves waste. Mismanagement in dry leaves will promote the campus area to look dirty. One method to control the dry leaves waste is the vermicomposting process. The purpose of this research is to evaluate the macronutrient content of dry leaves compost after the vermicomposting process. The research was conducted in the Faculty of Civil engineering and Planning, Universitas Islam Indonesia, Yogyakarta. The vermicompost sample in this study refers to the quality standards according to SNI 19-7030-2004 regarding compost quality standards. The results of vermicompost content value are obtained on day 56 is Phosphor amounting to 0.194%, amounting to 0.129% Potassium, and C / N ratio of 7.73. From the data that has been obtained can be concluded that the results of vermicompost are less effective as organic compost compared to the standards.
Co-Authors Abd. Rasyid Syamsuri Abdul Mutolib Abdurahman Abdurrahman Adi, Langit Cahya Adytama, Alhamdy Afiah, Irma Nur Ahmad Said Al-Hijrah, Al-Hijrah Ali Rahmat Andika Eko Prasetiyo Andika Eko Prasetiyo, Andika Eko Andiyan Andriana, Bibin B. Anggraini, Atika Annisa Nurhuda Romadhona Antomi Saregar Ardian Asyhari Aziza Anggi Maiyanti Bayu A. Sadjab Belista Gunawan Betta Kurniawan, Betta Bonno Andri Wibowo Bumi, Philosofi Setia Cengiz, Korhan Dewa, Parama Kartika Dewa, Parama Kartika Dewi Lengkana Dixit, Aparna Endah Kinarya Palupi Endah Kinarya Palupi Endah Kinarya Palupi Endah Kinarya Palupi Felga Zulfia Rasdiana Fitria Lestari Fitria Lestari Fredi Ganda Putra Fujiani, Dwi Haerul Anwar Handayani, Tri Wahyu Harnomo, Fajar Ikhwan Hartati, Niken Sri Hartono Hartono Hasan Said Tortop Hasan Said Tortop Hasan Said Tortop Hesti Herliantari Hirotaka Takahashi Hurien Helmi Husna, Ismalia I Putu Tedy Indrayana Ikah N. P. Permanasari Ikhsan Maulidi Ilma Ridhona Imama, Khoirunnisa Iqbal, Mochamad Iresha, Fajri Mulya Irma Nur Afiah Irwandani Irwandani Irzaman, Irzaman Iskandar Tsani Iskandar Tsani, Iskandar Iwamony, Steven Jermsittiparsert, Kittisak Kasam Kasam, Kasam Khoirunnisa Imama Khusnul Yakin Kittisak Jermsittiparsert Kurnia, Yogi Laila Puspita Laili, Ummiy Fauziyah Lengkana, Dewi Lusi Anggraini Mada Sanjaya WS Maharani, Fareza Chandri Michalska-Domańska, Marta Mochamad Iqbal Muawanah Muawanah Muhamad Syazali Muhamad Yasin Muhammad Nafian Muliadi Ramli Munifah Munifah Munifah Munifah, Munifah Muniroh, Luthfiyatul Nanda Ridki Permana Nangkula Utaberta Nurhanurawati Nurhanurawati Nurhanurawati Nurhanurawati Palupi, Endah Kinarya Panse, Vishal R puspitarum, deska lismawenning Rahma Diani Rahma Diani, Rahma Rahmad Junaidi, Rahmad Rahmi Ramadhani Rashidi Abdull Manap, Mohd Riana, Ulfa Ridhona, Ilma Ridwanulloh, M. Ubaidillah Rika Rahmawati Rika Rahmawati Rizka Dwi Saputri Rizqi Prastowo Rohim, Miftahul Romadhona, Annisa Nurhuda Saiful*, Saiful Santi Widyawati Saxena, Arti Siregar, Rahmat Nawi Sismanto Sismanto Steven Iwamony Sugeng Sutiarso Sugeng Sutiarso Sumarni, Tita Cardiah Suparman Suparman Suparman Suparman Syamsul Huda Syamsul Huda Tortop, Hasan Said Triani Triani Vina Apriliani Wahyudianto, Benny Wirani, Ayu Puspa Yakin, Khusnul Yasin, Muhamad Yetri Hasan Yudha Satya Perkasa Yudha Satya Perkasa, Yudha Satya Zakir Sabara