Article Per Year (5 Year)
p-Index From 2021 - 2026
0.444
P-Index
This Author published in this journals
All Journal Jurnal Pendidikan Matematika dan IPA Journal of Mechanical Engineering Science and Technology
Luthfiyah, Ishmah
Unknown Affiliation
Agriculture, Biological Sciences & Forestry Chemistry Education Energy Engineering Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mathematics Mechanical Engineering Physics

Published : 2 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 2 Documents
Search

 1 
Harnessing the Role of Carbon Black: A New Frontier for Energy-Density Supercapacitor Electrodes Komariyah, Ana Yuli; Luthfiyah, Ishmah; Albadi’ah, Ida Vaeruza; Nasikhudin, Nasikhudin; Meevasana, Worawat; Diantoro, Markus
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 9, No 1 (2025)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v9i12025p268

Abstract

The performance of activated carbon (AC)-based supercapacitor electrodes is often limited by poor electrical conductivity, prompting interest in conductive additives such as carbon black (CB). This study explores the transformative potential of CB as a conductive additive in AC-based supercapacitor electrodes and systematically investigates CB mass loadings of 0%, 5%, 10%, 15%, and 20%, using styrene-butadiene rubber (SBR) as the binder. The findings in this study demonstrate that 10% CB is the optimal loading, offering a balanced performance in terms of structure, morphology, and capacitance. X-ray diffraction (XRD) analysis reveals a distinct structural evolution at 10% CB, characterized by the exclusive emergence of a (100) peak at 43° 2θ, which indicates the formation of dense graphene-like layers and enhanced π-π electron delocalization. This promotes the formation of robust conductive networks, reducing electrode resistivity by 72%. Morphological and specific surface area characterization confirms the uniform particle distribution of an ultra-thin electrode AC-10% CB (26.5 μm) with a high surface area of 851.84 m²/g; this maximizes ion-accessible active sites and minimizes diffusion pathways. These combined effects result in a specific capacitance of 61.33 F/g, representing a 12% improvement over the pristine electrode (56.36 F/g) and 89.87% capacitance retention after 50 cycles. These results highlight the importance of optimizing CB loading: Lower concentrations (
COGNITIVE ASSESSMENT IN HIGHER EDUCATION: AN ANALYSIS OF LINEAR ALGEBRA MIDTERM EXAM ITEM QUALITY Putri, Reni Albertin; Suwito, Abi; Afifah, Ngizatul; Firmansyah, Frenza Fairuz; Rahmayani, Sekar Ayu; Angrenani, Arin Berliana; Luthfiyah, Ishmah
Jurnal Pendidikan Matematika dan IPA Vol. 17 No. 3 (2026): September 2026 (In press)
Publisher : Universitas Tanjungpura

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

Abstract

Cognitive assessment is an important part of learning evaluation, including in linear algebra courses. Essay-type exam questions are one of the instruments often used. However, several studies show that there is a lack of item feasibility studies conducted by teachers. This fact prompted this study, which aimed to determine the quality of midterm exam questions in linear algebra courses as cognitive assessment instruments. The study was conducted on a class of second-semester students in the Mathematics Education study program at the Universitas Jember. This descriptive evaluative design using a mixed-methods approach consisted of three stages: planning, implementation, and conclusion drawing. The research instrument consisted of five descriptive questions on linear algebra along with details of the desired learning outcomes. Based on the research, the researcher concluded that, in general, the five questions had met the minimum requirements in terms of validity, reliability, discriminating power, and difficulty index as cognitive assessment instruments for linear algebra learning. However, the researcher found that the average test results of students were still low. Therefore, the researcher urges further research to be conducted with a focus on improving the cognitive abilities of students in linear algebra courses or research on the development of additional cognitive assessments to better measure the abilities of students in linear algebra courses.
Co-Authors Abi Suwito Afifah, Ngizatul Albadi’ah, Ida Vaeruza Angrenani, Arin Berliana Firmansyah, Frenza Fairuz Komariyah, Ana Yuli Markus Diantoro Meevasana, Worawat Nasikh Putri, Reni Albertin Sekar Ayu Rahmayani