ReTII

A Implementation of Progressive Cavity Pump (PCP) Sand Abrasive Resistance Technology at Well Q-01 of Field X, Pertamina Hulu Rokan Regional 1

Agil Said Aqil — 2025-11-25

Well Q-01 in Field X, operated under the management of Zone 4 Pertamina Hulu Rokan (PHR) Regional 1, has encountered significant production challenges due to excessive sand production. This condition frequently leads to pump stuck incidents, resulting in considerable Loss Production Opportunity (LPO). The artificial lift system currently in use, the Electric Submersible Pump (ESP), has proven to be inefficient under abrasive fluid conditions, with an average run life of less than four months. Consequently, the well requires frequent servicing, which escalates operating expenditures and disrupts the continuity of oil production. As a strategic solution, PHR, through the Networked Collaboration for New Potential (NCNP) program initiated by Subholding Upstream (SHU), in collaboration with PT. SH, has conducted a pilot test of the Progressive Cavity Pump (PCP) equipped with Sand Abrasive Resistance technology. The PCP was selected for its ability to handle fluids with high sand content and abrasive characteristics. The implementation of PCP in Well Q-01 is expected to achieve several key outcomes: extending the run life to beyond four months, reducing the frequency of well servicing operations, lowering operational costs, and enhancing oil production performance. This initiative is anticipated to provide a more reliable artificial lift solution for sand-prone wells in Zone 4, thereby contributing to improved production stability and operational efficiency in PHR Regional 1.

The Water Quality Index of Springs in Bauro Village, Timor-Leste

Juvencio Dos Santos — 2025-11-26

The spring in Bauro Village, Timor-Leste, is used to meet the community's daily needs; therefore, an evaluation is needed to determine the quality of the groundwater from this spring. This research aims to assess groundwater quality, particularly using the Water Quality Index (WQI). Evaluation was carried out on 12 springs that emerged from limestone and sandstone. The research results show that not all springs meet the quality standards for drinking water or clean water. The WQI assessment shows that the majority of the 12 sampled sites (S1–S10 and S12) fall into the unsuitable category, indicating high levels of contamination from both natural and anthropogenic sources. Only Bauro spring S11 exhibited excellent water quality, while Luarai spring S12 showed poor drinking water quality and was unsuitable for clean water, reflecting localized contamination and possible mineral enrichment.

PENENTUAN FASIES DAN ARUS PURBA BERDASARKAN KETERDAPATAN STRUKTUR SEDIMEN DAN LITOLOGI PADA KECAMATAN NGLIPAR, KABUPATEN GUNUNG KIDUL, YOGYAKARTA

al hussein flowers rizqi — 2025-11-25

Research on paleocurrent directions in the Oyo Formation remains limited. Sedimentary structures used in determining paleocurrent directions can be observed in the Kali Oyo area, Nglipar District, Gunung Kidul Regency, Special Region of Yogyakarta, which serves as the study area. In this area of investigation, rock outcrops with a total measured stratigraphic thickness of 10.7 meters were identified, which is considered sufficiently representative for paleocurrent analysis. The objective of this study is to compile research findings by obtaining data on sedimentary structures and lithological variations along the measured stratigraphic section. Based on field observations, the lithology consists of calcilutite limestone, calcarenite limestone, and calcirudite limestone, while the sedimentary structures used to determine paleocurrent directions include slump structures and cross-bedding. Based on the collected data, facies and paleocurrent direction analyses were conducted. The area is interpreted to represent foreslope and winnowed edge sand facies, with the observed paleocurrent patterns being bipolar and polymodal.

Keyword : Oyo Formation, Paleo Currents, Facies. Gunung Kidul

Pengaruh Variasi Litologi Terhadap Kualitas Air Tanah di Daerah Semin dan Sekitarnya, Kecamatan Semin, Kabupaten Gunungkidul, Daerah Istimewa Yogyakarta

Robert Timotius Tuska — 2025-11-25

The research area is located in the physiography of the southern mountainous zone, precisely in the Semin area, Semin District, Gunungkidul Regency, Special Region of Yogyakarta is an area composed of two formations, namely the Oyo formation and the Semilir Formation which are composed of different rock units and have different rock compositions. The methods used in the study were TDS (Total Dissolve Solid), DHL (Electrical Conductivity), pH, and MAT (Groundwater Level). The purpose of this study is to determine the influence of lithology on groundwater quality and to find out groundwater that is suitable for consumption by the community. The pattern of groundwater flow to the elevation of MAT is more westward. The TDS value shows that the groundwater at the research site is classified as freshwater and has passed the groundwater quality test. EC values range from 209 – 1104 μs/cm. Groundwater pH testing ranges from 6.9 – 7.5. In the study area, there are predominantly carbonate sedimentary rocks, namely calcarenite 82.6% and clastic sediments, namely breccia 4.3%, and pyroclastic rocks, namely tuff 13.1%. Groundwater quality in the three types of lithology found to be suitable for consumption because it has not passed the water quality threshold. However, there is one well in lithology that has a slightly cloudy, smelly, and tasteful color, this well water is suspected to be polluted.

Keyword : Springs, Hydrogeology, Semin

Evaluasi Batuan Induk Minyak Bumi Berdasarkan Total Organic Carbon dan Rock Eval Pyrolysis Pada Daerah Nampu, Kecamatan Juwangi, Kabupaten Boyolali, Jawa Tengah

al hussein flowers rizqi — 2025-11-25

The research location is in Nampu Village, Juwangi District, Boyolali Regency, Central Java which is in the Kendang Zone and is included in the Pelang Formation. The method used in this study is TOC analysis to determine the percentage of organic material and REP to determine the type of organic matter that exists and to evaluate the potential of the shale rock of the study area as a parent rock. This study aims to determine the characteristics of shale bedrock in the research area and its relationship with oil and gas seepage found at the research site. The lithology found at the research site is in the form of interjaded napal/mudstone and calcarenite/grainstone at the bottom and napal/mudstone units with massive structures at the top. Based on the analysis of planktonic foraminifera fossils, the age of the rocks of the study site was N5-N7 in the lower layer, N6 in the Middle layer and N4-N6 in the upper layer. After being retracted, the age of the rocks at the research site has an Early Miocene age. The environmental facies of the deposition of the research site are in the Upper Interval of Parallel Lamination and Pellitic Interval which are characterized by the interplay of calkarenite/grainstone and napal/mudstone rocks at the bottom and napal/mudstone units at the top with a massive structure. The research location has a TOC content of 0.89% so it is categorized as having a medium (fair) organic matter richness. The results of the rock eval analysis of the surface sample have a medium (fair) category as a source rock that produces hydrocarbons, based on the comparison of the TOC and S2 diagrams, Tmax vs HI and HI vs OI samples have indications of Kerogen type III which tends to produce gases. The maturity of the parent rock sample based on the Tmax value has an immature level of maturity.

Keyword : Source Rock, Geochemistry, Oil and Gas Seepage

Penentuan Fasies dan Arah Arus Purba Berdasarkan Karakteristik Batuan Dan Struktur Sedimen Slump di Desa Ngleses, Kecamatan Juwangi, Kabupaten Boyolali, Jawa Tengah

al hussein flowers rizqi — 2025-11-25

The research location is in the Ngleses area, Juwangi District, Boyolali Regency, Central Java. The research location is in the Kendeng Zone and is included in the Kerek Formation. This study uses the Measuring Section method or rock profile using a meter. The purpose of this study is to determine the facies and direction of ancient currents based on the characteristics of the rocks and sediment slump structures found at the research site. From the field data that has been observed, there are 5 types of constituent rocks found at the research site, namely, limestone, sandstone, napal, napal, and carbonate sandstone. From the measurement of the Measuring Section or rock profile, it was found that the interplay of navel and clastic limestone of medium sand size at the bottom, followed by massive limestone, and carbonate sandstone at the top with a slump sediment structure. From the results of the measurement of the Measuring Section or rock profile, 3 deposition facies were obtained starting from the Classical Turbidite (CT) facies at the bottom, the Massive Sandstone (MS) facies in the middle, and the Slump Facies (SL) at the top. Based on the results of the rosset diagram, it was found that the ancient current pattern at the research location had a Bipolar pattern. The sediment slump structure found at the research site has a direction of N 182 ( E, from the slump sediment structure data can be interpreted as the direction of the ancient flow of the research location is north-south, and the source of sediment material that then forms rocks at the research site has a source from the north.

Keyword : Facies, Paleocurrent, Slump Structures

Desain dan Implementasi Alat Pemantauan Cuaca Self-Sustain Berbasis IoT untuk Dukungan Data Cuaca Real-Time

Oni Yuliani — 2025-11-25

Perubahan iklim dan dinamika cuaca ekstrem menuntut ketersediaan sistem pemantauan cuaca yang akurat, berkelanjutan, dan mudah diakses. Sistem konvensional yang bergantung pada infrastruktur listrik dan operasional manual sering kali menghadapi keterbatasan di wilayah terpencil. Sebagai respons terhadap tantangan tersebut, dikembangkan alat pemantauan cuaca self-sustain berbasis Internet of Things (IoT) yang mampu menyediakan data atmosfer secara real-time melalui integrasi sensor otomatis dan sumber energi surya. Sistem menggunakan sensor DHT22, BMP280, BH1750, anemometer digital, dan rain sensor yang dihubungkan ke mikrokontroler ESP32 dan dikirim ke cloud platform (ThingSpeak dan Blynk) untuk visualisasi data daring. Pengujian dilakukan selama tujuh hari di lingkungan terbuka Kampus ITNY dengan interval pengambilan data setiap lima menit. Hasil menunjukkan akurasi pengukuran dalam batas ±5% dibandingkan data BMKG, efisiensi energi 84,7%, dan tingkat keberhasilan transmisi data 97,6%. Sistem mampu beroperasi mandiri hingga 78 jam tanpa sinar matahari, membuktikan efektivitas rancangan self-sustain berbasis energi terbarukan. Penelitian ini mendukung pengembangan sistem pemantauan cuaca yang efisien, hemat energi, dan berkelanjutan untuk mendukung mitigasi bencana dan perencanaan sumber daya berbasis data real-time.

Rancang Bangun Prototipe Sistem Pemantauan dan Kontrol Utilitas Gedung Berbasis PLC SCADA

Tugino — 2025-11-25

The use of PLC and SCADA enables real-time monitoring and control systems that are expected to improve operational efficiency and optimize energy use. This research aims to design and implement a PLC-SCADA-based monitoring system for high-rise building utilities such as generators, fire detection, lighting, air conditioning, and water supply. This research contributes to innovation in building technology and provides practical benefits in the use of high-rise building utilities more efficiently and safely. The research method includes the design of hardware and software that are connected simultaneously with the building infrastructure. Several sensors are used to detect the performance and damage of the high-rise building utilities, then the SCADA system will monitor and control the high-rise building utilities if problems occur remotely. The results show that the prototype device can monitor real-time of energy use, lighting, room temperature and humidity, alarm in case of fire, and the system's reaction to changes in conditions that occur.

INVESTIGASI PERUBAHAN KAPASITAS MESIN DAN SISTEM BAHAN BAKAR TERHADAP PERFORMA KENDARAAN HONDA CS 1 2008

Edy Prasetyo — 2025-11-25

Penelitian ini bertujuan untuk mengetahui pengaruh perubahan kapasitas mesin dan sistem bahan bakar terhadap performa kendaraan Honda CS1 tahun 2008. Modifikasi dilakukan dengan memperbesar kapasitas mesin dari 125cc menjadi 150cc serta mengganti sistem bahan bakar dari karburator ke sistem injeksi (Fuel Injection). Metode penelitian yang digunakan adalah eksperimen dengan pengujian daya dan torsi menggunakan dynotest, uji emisi gas buang, serta konsumsi bahan bakar. Hasil pengujian menunjukkan bahwa modifikasi meningkatkan performa mesin secara signifikan. Daya maksimum meningkat sebesar 29,365% (dari 12,6 HP menjadi 16,3 HP) dan torsi naik 30,33% (dari 10,65 Nm menjadi 14,20 Nm). Emisi gas buang yang dihasilkan mesin injeksi lebih ramah lingkungan dibandingkan karburator, dengan penurunan kadar HC dan CO yang signifikan. Konsumsi bahan bakar juga lebih efisien pada mesin injeksi dengan hasil 41,7 km/l dibandingkan 39,9 km/l pada mesin karburator. Penelitian ini membuktikan bahwa perubahan kapasitas mesin dan sistem bahan bakar berpengaruh positif terhadap performa, efisiensi, dan emisi kendaraan.

Implementasi BIM dalam Pembuatan Sistem Pelaporan Monitoring Progress Pekerjaan Konstruksi (Studi Kasus Proyek Pembangunan Gedung Pusat Onkologi Rs. Soeradji Tirtonegoro)

Lilis zulaicha — 2025-11-25

Pelaksanaan proyek konstruksi berskala besar, seperti pembangunan Gedung Pusat Onkologi RSUD dr. Soeradji Tirtonegoro, menuntut sistem pelaporan yang efisien, terstruktur, dan informatif. Permasalahan utama yang sering terjadi adalah keterbatasan Pejabat Pembuat Komitmen (PPK) dalam melakukan pengawasan dan kendali proyek secara optimal akibat kompleksitas pekerjaan serta tidak adanya format baku pelaporan. Penelitian ini bertujuan untuk mengembangkan sistem pelaporan manajemen konstruksi berbasis Building Information Modeling (BIM) sebagai solusi untuk meningkatkan efektivitas kemajuan pekerjaan proyek. Metode yang digunakan mencakup pengolahan gambar kerja (shop drawing) dalam format presentasi (PPT) dengan simbolisasi warna sebagai indikator progres, yang selanjutnya dimodelkan ke dalam bentuk tiga dimensi menggunakan perangkat lunak Autodesk Revit. Hasil penelitian menunjukkan bahwa sistem pelaporan berbasis visual 3D ini mampu meningkatkan keterbacaan, mempercepat proses monitoring, serta mendeteksi keterlambatan atau ketidaksesuaian pelaksanaan proyek secara lebih dini. Model BIM terbukti memperkuat koordinasi dan pengambilan keputusan melalui penyajian data progres yang akurat dan mudah dipahami oleh seluruh pemangku kepentingan, termasuk pihak non-teknis. Dengan demikian, integrasi gambar kerja simbolik dan BIM direkomendasikan sebagai metode pelaporan progres yang adaptif dan efektif untuk proyek-proyek konstruksi sejenis

INTERNET OF THINGS BASED TEMPERATURE AND HUMIDITY MONITORING OF THE CALIBRATION LABORATORY ROOM AT BBSPJI KERAJINAN DAN BATIK

Zaenal Muttaqien — 2025-11-25

This study aims to develop an Internet of Things (IoT)-based temperature and humidity monitoring system for the Calibration Laboratory of the Center for Standardization and Industrial Services for Handicrafts and Batik (BBSPJIKB). The system is designed to support environmental monitoring that requires stable temperature and humidity conditions in accordance with the SNI ISO/IEC 17025:2017 standard. The system utilizes a DHT11 sensor, NodeMCU ESP8266 microcontroller, and the Blynk application as a remote monitoring interface. Data are transmitted via Wi-Fi and displayed in real time on mobile devices. Experimental results show that the system operates stably with an average response time of 1.9 seconds, 98% connection stability, and 45% higher monitoring efficiency compared to manual methods. Therefore, IoT technology proves effective in supporting the digitalization of laboratory environmental monitoring systems efficiently and reliably.

Penentuan Kurva Tekanan Kapiler Menggunakan Metode Buckley Laverett: Pendekatan Pengolahan Data untuk Aplikasi Simulasi Reservoir

Lia Yunita — 2025-11-25

Tekanan kapiler memegang peran penting dalam menentukan distribusi dan mobilitas fluida di dalam pori batuan. Hubungan antara tekanan kapiler, kejenuhan fluida, serta permeabilitas relatif menjadi dasar dalam memahami dinamika perpindahan fluida pada media berpori. Tujuan penelitian ini mengembangkan pendekatan pengolahan data berbasis model matematis Buckley Laverett untuk mentransformasikan data saturasi dan tekanan menjadi kurva tekanan kapiler yang dapat digunakan sebagai input dalam simulasi numerik reservoir. Metode yang digunakan pengolahan data transformasi data special core analysis dari laboratorium menjadi model tekanan kapiler menggunakan pendekatan matematis Buckley Laverett yang dapat diaplikasikan langsung pada simulasi reservoir. Hasil analisis tekanan kapiler pada dua rock region membuktikan bahwa tekanan kapiler berkurang secara eksponensial seiring meningkatnya saturasi air, dengan nilai yang lebih rendah pada batuan berporositas dan permeabilitas tinggi. Melalui pendekatan ini, diperoleh kurva tekanan kapiler yang mampu menggambarkan hubungan fisik antara gaya antarmuka fluida dengan sifat batuan, serta dapat digunakan sebagai input valid dalam simulasi reservoir.

Deteksi Sentimen Publik terhadap Isu Lingkungan di Platform X (Twitter) Menggunakan Naïve Bayes dan Support Vector Machine untuk Mendukung SDGs 13: Climate Action

Noni Fauzia Rahmadani — 2025-11-25

Environmental issues are among the most discussed topics on social media, gaining global attention due to increasing awareness of climate change. Twitter, as one of the largest social media platforms, provides a valuable data source for understanding public perceptions of environmental topics. This study aims to detect public sentiment toward environmental issues on Twitter using the Naïve Bayes and Support Vector Machine (SVM) algorithms. The dataset used in this study is the Climate Change Twitter Sentiment Dataset from Kaggle, which contains thousands of labeled tweets related to climate change with positive, negative, and neutral sentiments. The research stages include text preprocessing (cleaning, tokenizing, and stopword removal), feature extraction using Term Frequency–Inverse Document Frequency (TF-IDF), model training, and algorithm evaluation. The experimental results show that SVM achieved higher accuracy than Naïve Bayes, with 89.4% and 84.7%, respectively. These findings indicate that SVM is more effective in identifying sentiment patterns. This research supports the achievement of Sustainable Development Goal (SDG) 13: Climate Action by leveraging artificial intelligence to analyze public opinion on environmental issues.

Analisis Unjuk Kerja Plat Penyerap Corrugated-V pada Sistem Destilasi Surya Air Laut untuk Peningkatan Efisiensi Termal

Arfan Halim — 2025-11-25

This was conducted to analyze the performance of a solar seawater distillation system equipped with a corrugated-V absorber plate at an angle of β = 20°. The experiment was conducted at the Workshop of Politeknik Sinar Mas Berau Coal to investigate the effect of absorber plate geometry on the absorptivity, useful energy, and distillation efficiency. The experimental results indicate that the absorber plate with a 20° angle achieved the highest average absorptivity value of 0.989, which was identified as the optimal configuration for the solar distillation system. The average useful energy produced during the distillation process was 683.11 kJ, with an average system efficiency of 16.53%. The maximum efficiency of 25.67% was recorded at 14:00 local time, and the total amount of distilled water produced was 300 ml. These findings demonstrate that the corrugated-V absorber plate with a 20° angle effectively enhances solar energy absorption and sustains the evaporation process, even under decreasing solar radiation intensity.

FMEA-Based Risk Mitigation Strategy for Preventing Final Drive Component Failures in Bulldozers

Sutrisna Sutrisna — 2025-11-25

Failures in bulldozer final drive components are among the leading causes of increased downtime and maintenance costs in heavy equipment operations, particularly in mining and construction sectors. This study aims to analyze the potential failure risks of final drive components and to formulate effective risk mitigation strategies using the Failure Mode and Effects Analysis (FMEA) method. Data were collected through field observations, interviews with maintenance technicians, and analysis of historical failure records and Scheduled Oil Sampling (SOS) results. Each failure mode was evaluated based on three main parameters: Severity (S), Occurrence (O), and Detection (D), to determine the Risk Priority Number (RPN). The results indicate that failures in bearing and seal oil components have the highest RPN values 270, making them the primary focus of mitigation. Proposed strategies include increasing inspection frequency, improving lubrication quality control, and implementing condition-based maintenance systems. The application of these mitigation strategies is expected to reduce the likelihood of component failures and enhance the reliability of the bulldozer final drive system

The Comparison of Water and Acid Leaching Methods to Reduce Ash and Inorganic Mineral Content in Teak Sawdust Biomass

Muhammad Arief Saputro — 2025-11-25

Biomass is the fourth largest renewable energy source in the world, accounting for approximately 10% of the total global primary energy supply. Every year, a large amount of teak wood sawdust is produced from the manufacturing of furniture, beds, wooden decorations, and various other products. This waste has no economic value and requires considerable storage space, causing problems in handling and disposal. Therefore, utilizing this forestry residue for biofuel production is a sustainable and economically beneficial approach.

However, the main challenge in its utilization lies in its high ash and inorganic mineral content, which can reduce energy conversion efficiency and the calorific value of the product. This study aims to compare the effectiveness of washing methods using water and acid solutions in reducing ash content and increasing the calorific value of teak wood sawdust. The research was conducted experimentally in a laboratory, involving several stages: material preparation, washing treatment (water and acid), drying, ash content and calorific value analysis, and result evaluation. The treatments were carried out at mass ratios of 1:25, 1:50, and 1:75, washed for 2 hours using a magnetic stirrer, followed by filtration, rinsing to neutral pH, and drying at 105 °C for 6 hours.

The results showed that washing with 1 M HCl consistently produced a greater mass reduction of teak wood sawdust compared to deionized water at all ratios, indicating that the acid method is more effective in reducing the inorganic content of biomass.

Dampak Media Sosial Facebook dan Instagram Terhadap Kunjungan Wisatawan di Desa Wisata Tambakbulusan

Mulyono Mulyono — 2025-11-25

The development of social media has changed the pattern of tourist promotion and visitation decisions, offering significant opportunities for local tourist destinations. This study aims to analyze the specific influence of Facebook and Instagram on increasing tourist visits, with a case study of Tambakbulusan Tourism Village, Glagah Wangi Beach, Demak Regency. The research method used is descriptive quantitative. Data were collected through questionnaires from 175 tourist respondents and analyzed using SmartPLS 3.0 software. The results of hypothesis testing proved that both social media platforms have a positive and statistically significant influence. Facebook has an influence with a t-value of 7.787 (p-value 0.000), and Instagram shows a stronger influence with a t-value of 8.390 (p-value 0.000). These findings confirm that digital promotion strategies through both platforms are effective in driving tourist visitation decisions. This study provides an empirical contribution to the digital tourism marketing literature, particularly for developing local tourist destinations. The practical implication of this study is the need for destination managers to optimize strategic content and engagement across both platforms to maximize promotional impact.

Study of the Effect of Blast Geometry Based on Multiple Linear Regression Analysis on Airblast Value at PT. X

Ilham akhmad — 2025-11-25

Airblast is an excessive air pressure wave generated by blasting, which can cause environmental disturbances and structural damage in the vicinity of the mining area. The amount of explosive charge and stemming length were identified as the main variables influencing airblast intensity. The research method employed a quantitative approach, utilizing primary data consisting of blasting geometry, explosive charge amount, stemming length, measurement distance, and airblast measurement results using a Micromate, as well as secondary data in the form of maps and technical information of the study site. Multiple linear regression analysis was used to determine the relationship and contribution of each variable to the Sound Pressure Level (SPL) of airblast. The results indicated that both variables significantly affected airblast magnitude. An increase in the amount of explosive charge tended to raise SPL values, while an increase in stemming length reduced them. Most SPL values were below the SNI 7570:2010 noise level standard, although several instances exceeded the recommended limits, necessitating adjustments to blasting design. In conclusion, airblast control can be optimized by regulating the amount of explosive charge per hole and applying stemming lengths suited to local geological conditions. Recommendations include adjusting the powder factor and using stemming materials with optimal density and length to minimize airblast impact

Persentase Tereduksi Penggunaan Sequential Blasting terhadap Ground Vibration pada Kegiatan Peledakan di Pit. Pinang A9, PT. Bukit Baiduri Energi, Provinsi Kalimantan Timur

Rabin Daruis — 2025-11-25

Blasting activity is a rock breaking activity that helps facilitate dismantling in excavation activities. At PT. BBE still carries out blasting activities to date in helping to break up the rocks in the mining location, especially at the PIT location. Pinang A9. Blasting activities themselves have quite dangerous impacts on the surrounding environment, one of which is ground vibration which can have quite serious impacts if the vibration value is high enough. In an effort to carry out this activity, a fairly high vibration value was still found in the theoretical calculation with an average PPV value of 1.68 mm / s. The rock conditions that dominate the blasting activity location are claystone and sandstone rocks where the compressive strength value is quite weak, which is in the soft category with a value of 8 to 16 Mpa. So in the process of this activity, a solution is needed to dampen the existing vibrations, in this case PT. BBE chose to use the Sequential Blasting technique solution where in its application Dummy Holes are given as an additional delay to make many blast holes into small groups when exploding. After the blasting activity was carried out, the PPV value was found to be reduced quite drastically with an average value of 0.46 mm/s, where in this case the Sequential Blasting technique can reduce the magnitude of vibration by up to 69.55%.Keywords: Blasting Geometry, Powder Factor, Optimum Cost, Cost Saving

Redesign of the Ultimate Pit Limit Based on Re-Analysis of Lowwall Slope Stability at Pit Mahakam Barat PT Insani Baraperkasa Loa Janan Block Kutai Kartanegara Regency East Kalimantan Province

Sonia R M Rembang — 2025-11-25

This research aims to perform a re-analysis of the lowwall slope stability and a redesign of the ultimate pit limit at Pit Mahakam Barat, PT Insani Baraperkasa. The analysis was conducted to evaluate the stability condition of the initial slope design and to determine an appropriate slope geometry that meets both safety and economic feasibility criteria based on the latest geotechnical conditions. The results indicate that the initial lowwall slope design has a Factor of Safety (FoS) of 1.22 and a Probability of Failure (PoF) of 13.06% under static conditions, which falls into the critical category. The redesigned slope geometry for each lithology—coal (slope angle 60°, bench height 8 m, berm width 5 m), sandstone (35°, 10 m, 7 m), and claystone–siltstone (40°, 10 m, 5 m)—produced an overall slope angle of 32°. Under dynamic conditions, the redesigned slope achieved an FoS value of 1.41 and a PoF of 1.12%, indicating a stable slope condition. Furthermore, the redesign led to an increase in both coal reserves and overburden volume. The total coal reserves increased by 14,050.16 MT, from 4,520,898.73 MT to 4,534,948.89 MT, while the overburden volume increased by 288,673.28 BCM, from 43,616,288.13 BCM to 43,904,961.41 BCM. The stripping ratio (SR) also increased slightly from 9.65 to 9.68, yet it remained below the company’s maximum economic SR limit of 11.63. Therefore, the redesigned pit is considered both technically stable and economically feasible

A Model of Regenerative Architecture on a Post-Mining Land in Purwokerto

Alifia Kautsar — 2025-11-25

Indonesia has a complex geological structure, offering significant potential in natural resources, particularly in the mining and excavation sectors. As an administrative city, Purwokerto has undergone rapid urban development. This growth has led to an increasing demand for construction materials, much of which is sourced from mining activities in Banyumas Regency. Such activities require land reclamation efforts to restore land productivity. Post-mining land reclamation can be carried out through several strategies, including land conversion for agricultural purposes and tourism. The conversion and recovery of land productivity are translated into the design of an Urban Farming Center as both an agricultural and edu-tourism facility within urban and suburban areas. The design process adopts a descriptive method by analyzing secondary data relevant to the planning and design of the Urban Farming Center. The data sources include spatial planning policies, site survey findings, and precedent studies of urban farming and regenerative architecture projects implemented in other regions. Primary data were obtained through site observation and analysis of existing land conditions, while secondary data were collected from scientific journals, local regulations, and urban planning documents. All data were synthesized to develop a design approach and architectural outcome. A regenerative architecture approach was applied to restore the ecosystem of the post-mining site while creating an adaptive and sustainable environment. The design of the Urban Farming Center aims not only to function as a hub for urban agriculture but also to serve as a space for education, eco-tourism, and community engagement

Aquifer Investigation in Cibodas Bogor, West Java, Indonesia, using a geoelectrical method and 2D subsurface modeling

al hussein flowers rizqi — 2025-11-25

This study was conducted at the location of a cattle pen (Kafeel Farm) in Bogor City, more precisely in the Cibodas village. The purpose of this study is to use subsurface cross-sectional correlations to get a general picture of the lithology, geological structure, and subsurface aquifers. In addition to improving knowledge of the depth and distribution of aquifers in the study area, the contribution of this research will influence residents' groundwater searches. The geoelectrical method with Schlumberger configuration is the methodology employed in this study. In the research area, there were three points of observation in the geolectrical acquisition data. From oldest to youngest, the study area's lithology consists of sandstone with mudstone intercalations (Serpong Formation) and limestone lithology (Bojongmanik Formation). The weathering of limestone and sediments from the Cisadane River is used to interpret the surface soil. At a depth of 8 to 35 meters and a thickness ranging from 10 to 18 meters, the study area's aquifer contains shallow groundwater. Drilling is advised at observation point 2, at a depth of approximately 8 to 18 meters

Keyword : Aquifer, Serpong Formation, Bogor, Geoelectrical; Schlumberger

Preparasi Minyak Goreng Bekas sebagai Bahan Baku Pembuatan Biodiesel dengan Adsorben Arang Aktif dari Tempurung Kelapa

Haryono — 2025-11-25

Cooking oil, particularly from palm oil, is a primary need in households and the food and culinary industry. The use of this cooking oil ultimately results in waste in the form of waste cooking oil. Waste cooking oil has the potential to be used as a raw material in the production of biodiesel, a type of renewable energy. However, before being used in the biodiesel production process, the waste cooking oil must be separated from its impurities. One method in the impurity separation stage from waste cooking oil is adsorption with various types of adsorbents, such as activated charcoal. Coconut shells are a potential biomass waste as a raw material for producing activated charcoal. The aim of this study was to determine the effect of temperature and adsorbent content on the adsorption of waste cooking oil with activated charcoal from coconut shells on the characteristics of waste cooking oil as a raw material for biodiesel synthesis. The research procedure includes two main stages, namely the purification of waste cooking oil by sedimentation, filtration, evaporation, and sedimentation methods; then the synthesis of biodiesel from waste cooking oil after purification. The results of the study showed that the adsorption of waste cooking oil at a temperature of 70 °C and an activated charcoal content as an adsorbent of 5% (w/v) produced waste cooking oil with the best quality, based on the parameters of density, viscosity, acid number, and iodine number. Biodiesel produced from waste cooking oil that has been purified under optimal adsorption conditions has met the biodiesel quality standards according to Indonesian National Standard, SNI 7182-2015.

Geologi, Genesis dan Karakteristik Endapan Laterit Bauksit di Daerah Melugai, Kalimantan Barat

Muhammad Hery Setiyawan — 2025-11-25

Lateritic bauxite deposits found in Melugai Village, West Kalimantan, are located within a prospective laterite zone. This study aimed to investigate the geological setting and genesis of the bauxite deposits to determine their controlling factors and resulting characteristics. Methods included geological mapping, petrographic analysis, and laboratory tests (XRD and XRF). The Melugai area is underlain by the Triassic Pinoh Metamorphic Rocks, specifically metatuff and metaandesite units. Geomorphologically, the region features gently sloping to inclined undulating hills with a dendritic drainage pattern. Bauxite formation is primarily controlled by parent rock type, time, tropical climate, and low-relief geomorphology. The lateritization process intensifies weathering and leaching of soluble elements (Na, K, Ca), leaving a residue rich in aluminum hydroxide (Al(OH)₃) that subsequently hardens into bauxite. The deposits are classified into two types based on their parent rock. XRD analysis identified dominant minerals: gibbsite, hematite, goethite, kaolinite, quartz, and sodalite. XRF analysis revealed a significant difference in quality. Bauxite derived from metatuff has an average Al₂O₃ content of 47.53% (medium grade), while bauxite from metaandesite has an average Al₂O₃ content of 32.25% (low grade). It is concluded that bauxite sourced from the metatuff parent rock exhibits better quality and a stronger degree of laterization.

Pendugaan Akuifer dengan Geolistrik dan Pemetaan Geologi Ceporan, Klaten

Insern Loisa Marsyom — 2025-11-25

This research was conducted in Ceporan Village, Gantiwarno District, Klaten Regency, Central Java Province. The aim was to identify aquifer potential using the Schlumber configuration geoelectric method and surface mapping, including lithology, porosity, and permeability data. The geoelectric method was used to determine subsurface conditions through variations in resistivity values, and surface mapping was used to identify the exposed lithology and the porosity and permeability of the rocks. The main problem addressed in this study was the subsurface conditions in the study area and the potential for aquifers based on the resistivity characteristics of the rocks. Interpretation results indicate the presence of rock layers consisting of sediment, silt-clay, clay, sandstone, claystone, siltstone, and andesite breccia. Analysis results indicate the presence of a sandstone layer at a depth of 3-25 meters, interpreted as a potential aquifer zone. This research is expected to serve as a basis for planning sustainable groundwater resource management in the southern Klaten region, especially in the Ceporan area.

Keyword : Geoelectric, Aquifer, Resistivity, Mapping

Kontrol Fasies dan Lingkungan Pengendapan terhadap Kualitas Batubara Formasi Warukin di Daerah Haruai, Tabalong, Kalimantan Selatan

Nodyka Elkawi Hawinu — 2025-11-25

Coal deposits of the Warukin Formation in South Kalimantan developed within a complex deltaic system, where variations in facies and depositional environments play a major role in controlling the distribution and quality of coal seams. Understanding the relationship between lithofacies characteristics, depositional settings, and coal quality parameters is fundamental for geological interpretation of coal-bearing formations. The analysis was based on borehole log data (gamma-ray and density) and core descriptions to identify facies and depositional environments. The interpretation reveals three main facies: sandy claystone (Crevasse Splay–Interdistributary Bay), carbonaceous claystone (Interdistributary Bay), and coal (Swamp). Overall, the depositional setting is interpreted as a Transitional Lower Delta Plain influenced by tidal activity and fine-grained sedimentation. Proximate analysis indicates that coal seams 6–9 have calorific values ranging from 4968 to 5206 kcal/kg, with low sulfur content (average 0.48%) and ash content of 18.38%. These characteristics classify the coal as High Volatile C Bituminous to Subbituminous B Coal. Variations in lithofacies and the dominance of fine sediments within the Transitional Lower Delta Plain environment contribute to a decrease in calorific value due to higher mineral impurities during deposition

The Comparison of Transportation Network Node Density in Balikpapan City in 2019 and 2025

Iwan Aminto Ardi — 2025-11-25

This research analyzes the concentration of land transport network intersections in Balikpapan City for 2019 and projects the figures for 2025. Balikpapan, as the primary entry and logistics hub for Indonesia's planned new capital, is undergoing significant infrastructure changes, necessitating this study to assess road network density variations pre- and post-major development projects. The methodology used is Kernel Density spatial analysis, applying data from the 2019 Indonesian Topographic Map and 2025 Online Street Map, with results visualized through graduated color schemes. Key findings show a substantial increase in network intensity and geographical coverage between the two periods. In 2019, the peak density (81.71) was primarily concentrated in the southern and central parts of the city. By 2025, the peak density value is projected to rise to 111.71, with high-density zones visibly expanding to cover nearly all northern and eastern areas. This shift suggests considerable infrastructure growth and a more balanced distribution across the administrative area, leading to a change in transportation focal points. The study recommends future strategies focusing on upgrading mass transit, reducing reliance on personal vehicles, and implementing comprehensive traffic control measures to improve the efficiency of the burgeoning network.

Spatial Modelling Untuk Analisis Ketimpangan Akses Transportasi Perkotaan di Bandar Lampung

iman ceria invokafit — 2025-11-25

Modern urban areas face complex challenges related to the interconnection between transportation systems, land use, and the quality of accessibility for their residents. Accessibility, which refers to an individual's ability to reach activities, services, jobs, or facilities within a certain time and cost limit, becomes an important indicator in urban and regional planning because it reflects how urban space facilitates mobility, social and economic interactions, as well as spatio-temporal inclusion. For instance, in the context of developing cities, studies have shown that inequalities in transportation accessibility can reinforce spatial-social disparities and reduce mobility efficiency for residents (Giannotti et al., 2021) [1]. In line with this, sustainable urban development policies increasingly emphasize that improving vehicle mobility is not only important, but also how transportation systems and road networks support equitable and efficient accessibility. Therefore, this study will conduct spatial modeling to identify and analyze transportation accessibility inequalities in the city of Bandar Lampung, with the aim of providing recommendations for more equitable urban and regional planning that supports mobility and urban growth.

Variasi Heat Input Terhadap Kekuatan Tarik dan Kekerasan Vickers Sambungan Butt Joint Las SMAW Pada Baja Karbon Rendah

Muhammad Fa’iq Kafiluddin — 2025-11-25

Penelitian ini bertujuan untuk mengetahui pengaruh heat input terhadap uji komposisi kimia, uji kekuatan tarik, dan uji kekerasan vickers sambungan butt joint las SMAW pada baja karbon rendah. Penelitian ini menggunakan material pipa baja karbon, dengan ukuran 200 mm x Ø 80 mm x 5 mm, kampuh V sudut 60°. Dilas menggunakan mesin las SMAW AOTAI ARC500, 2 layer, dengan HI 143,29 Joule/mm, HI 157,99 Joule/mm, dan HI 186,78 Joule/mm. Elektroda yang digunakan E7016 Ø 2,6 mm. Hasil uji komposisi kimia bahan pipa baja mengandung kadar C 0,09 %. Hasil uji kekerasan vickers, nilai kekerasan pada raw material sebesar 131,05 kg/mm², sedangkan bahan setelah dilas nilai kekerasan mengalami peningkatan sebesar 0,31 %. Nilai kekerasan tertinggi pada daerah weld metal dengan HI 143,29 Joule/mm sebesar 178,30 kg/mm². Hasil uji kekuatan tarik bahan RM dibandingkan dengan bahan yang sudah dilas mengalami penurunan kekuatan tarik sebesar 0,09 %. Dari ketiga variasi HI uji tarik, nilai tegangan tarik rata – rata tertinggi pada HI 143,29 Joule/mm sebesar 49.91 kg/mm². Nilai regangan rata – rata tertinggi pada HI 157,99 Joule/mm sebesar 0,206 %. Hasil uji tarik pada penelitian ini semua spesimen yang dilas putusnya pada daerah HAZ, menunjukan bahwa pada daerah WM tidak ada cacat (porositas).

Kebutuhan Infrastruktur Air Minum, Drainase, dan Air Limbah sebagai Instrumen Perencanaan Pembangunan Wilayah (Studi Kasus: Kabupaten/Kota di Indonesia)

Fahril Fanani — 2025-11-25

Urbanisasi yang pesat di Indonesia menuntut penyediaan infrastruktur air (air minum, drainase, dan air limbah) yang memadai, namun perencanaan infrastruktur seringkali bersifat reaktif terhadap pertumbuhan. Penelitian ini bertujuan untuk memproyeksikan kebutuhan infrastruktur air minum, drainase, dan air limbah sebagai instrumen strategis untuk perencanaan pembangunan wilayah. Pendekatan kuantitatif deskriptif digunakan pada 10 sampel kabupaten/kota di Indonesia (termasuk DKI Jakarta, Surabaya, Balikpapan, dan Batam). Proyeksi kebutuhan dihitung untuk horizon waktu 5, 10, dan 20 tahun (2030, 2035, 2045) menggunakan metode proyeksi penduduk (geometrik) dan standar teknis (SNI, Metode Rasional). Hasil penelitian menunjukkan peningkatan kebutuhan infrastruktur yang substansial di semua lokasi studi. Laju pertumbuhan persentase tertinggi diproyeksikan terjadi di Batam dan Balikpapan, sementara volume kebutuhan absolut terbesar tetap berada di DKI Jakarta. Analisis mengidentifikasi tiga tantangan utama: (1) skala investasi finansial yang masif; (2) keterbatasan ketersediaan sumber daya (air baku dan lahan); dan (3) tekanan ganda dari alih fungsi lahan dan dampak perubahan iklim. Studi ini menyimpulkan bahwa proyeksi kebutuhan infrastruktur tidak boleh hanya menjadi output teknis. Proyeksi ini harus berfungsi sebagai instrumen input strategis dan pengendali dalam perencanaan tata ruang (RTRW), mendorong pergeseran paradigma dari reaktif menjadi proaktif (perencanaan berbasis kapasitas).

Mudflat facies in the lower part of Nanggulan Formation, Kulon Progo Mountain, Yogyakarta, Indonesia

siti Nuraini — 2025-11-25

The mudflat facies type is commonly interpreted as layered parallel limestone mudstone with horizontal bedded located near the coastline. However, the current mechanics and feeder systems are often found in its interbeds in very fine to medium-grained sandstone lithology. This study will investigate the mudflat facies type of the Nanggulan Formation with interbeds of very fine to fine-grained sandstone and calcilutite limestone lithology. The method used is to create a vertical stratigraphic sections of the Nanggulan Formation using Watupuru river. Sedimentary structures found indicate the role of tidal current mechanics such as heterolithic, herringbone, mud drapes, neap and spring interbedding, double mud lamination, and wrinkled lamination. Ichnofossils also vary in this facies. The river distribution system is controlled by two different sources, from the land and the sea, formed simultaneously in the intertidal zone.

Perencanaan Desa Wisata Terpadu dengan Konsep Arsitektur Tropis di Desa Karangtengah, Cilongok, Banyumas

DWI ATTALA RIZQI — 2025-11-25

Perencanaan Desa Wisata Terpadu di Desa Karangtengah, Cilongok, Banyumas dilatarbelakangi pergeseran tren pariwisata dari wisata massal ke wisata alternatif yang menekankan pengalaman berbasis alam, budaya, edukasi, dan partisipasi masyarakat. Penelitian ini bertujuan merancang kawasan wisata terpadu dengan penerapan prinsip arsitektur tropis yang sesuai iklim lokal. Metode yang digunakan adalah pendekatan campuran, kualitatif untuk analisis sosial-budaya dan kuantitatif untuk perhitungan ruang dan fasilitas. Hasil perencanaan mencakup zonasi wisata air, edukasi flora-fauna, kuliner, seni budaya, penginapan, serta fasilitas penunjang; desain arsitektural mengimplementasikan atap miring, ventilasi silang, penggunaan material lokal, dan tata massa responsif iklim. Perencanaan ini diharapkan meningkatkan daya tarik wisata, melestarikan budaya, membuka lapangan kerja, dan meningkatkan kesejahteraan masyarakat secara berkelanjutan.

Comparison of Multinomial Naïve Bayes and Bernoulli Naïve Bayes Methods in Sentiment Analysis of National Team Naturalization Based on Comments on Instagram

Andrianus Dwi Haryo — 2025-11-25

Football is the most popular sport in Indonesia, with the National Team serving as a symbol of national pride. One of the most debated issues is the naturalization of foreign players to strengthen the team. Public opinions on this topic are widely expressed on social media, especially Instagram. This study aims to analyze sentiment from 4,258 Instagram comments related to the naturalization issue by comparing the performance of Multinomial Naïve Bayes and Bernoulli Naïve Bayes Methods. The analysis process includes preprocessing, translation using the Google Translate API, sentiment labeling with VADER, TF-IDF vectorization, and data balancing using SMOTE. The classification performance is evaluated using a confusion matrix with metrics such as accuracy, precision, recall, and F1-score. The results show that Multinomial Naïve Bayes achieves better performance with 74.65% accuracy, 75.96% precision, 74.65% recall, and 74.32% F1-score under 10-fold cross-validation and alpha 0.01 compared to Bernoulli Naïve Bayes.

Perbandingan antara Energi Meter Berbasis ESP32+PZEM004 dengan Smart Plug Komersial

Djoko Suwarno — 2025-11-25

Electric Energy consumption monitoring is an important process to improve energy efficiency. Today, there are two approaches to energy monitoring: first in build an energy meter using ESP32 and PZEM-004T module, and second is using a commercial smart plug. This paper compares those approaches in accuracy, features, flexibility, price, and complexity. Based on the result and discussion, results ESP32+PZXEM 004T system performs better in flexibility as needed. On the other hand, commercial smart plugs give easyly in use (plug and play). Better integration in the smart home ecosystem and a smooth Graphical User Interface. An energy meter developed shows measure parameters, ie, voltage (V), currents (A), Power factor, real power (W), apparent power (VA), energy (Wh), frequency (Hz), and time ON, energy meter was built to measure usage energy for electric devices for short-term usage.

Pemanfaatan Langsung Air Panas Bumi Gunung Ungaran untuk Terapi Kesehatan Masyarakat: Pendekatan Geokimia dan Nilai Geoheritage

brany kurnianto — 2025-11-25

Kawasan panas bumi Gunung Ungaran, Jawa Tengah, memperlihatkan berbagai manifestasi hidrotermal aktif seperti mata air panas Gedongsongo, Nglimut, dan Diwak yang memiliki potensi tinggi untuk pemanfaatan langsung (direct use), khususnya dalam bidang kesehatan masyarakat. Penelitian ini bertujuan untuk mengkarakterisasi geokimia air panas bumi di kawasan tersebut dan menilai potensinya sebagai media terapi kesehatan berbasis pendekatan geohealth dan geoheritage. Hasil pengukuran lapangan menunjukkan suhu air 38–45°C, pH netral–sedikit basa, dan konduktivitas sedang. Analisis laboratorium mengonfirmasi bahwa air panas Ungaran didominasi tipe Na–HCO₃ dengan kandungan signifikan SiO₂, Ca²⁺, Mg²⁺, HCO₃⁻, dan SO₄²⁻. Komposisi geokimia tersebut berperan dalam proses regenerasi kulit, relaksasi otot, peningkatan sirkulasi darah, dan potensi penyembuhan penyakit kulit, sebagaimana didukung oleh hasil wawancara pengguna mata air panas yang melaporkan perbaikan keluhan kulit dan penurunan stres setelah terapi. Selain aspek geokimia, keberadaan situs Candi Derekan sebagai bukti arkeogeologis pemanfaatan air panas sejak masa kerajaan kuno memberikan dimensi geoheritage dan geo-culture yang signifikan. Integrasi antara nilai ilmiah, budaya, dan manfaat kesehatan ini menunjukkan bahwa sistem panas bumi Ungaran tidak hanya penting sebagai sumber energi, tetapi juga sebagai aset geoheritage yang mendukung kesejahteraan masyarakat. Temuan ini membuka peluang pengembangan geowisata kesehatan berkelanjutan berbasis komunitas, sekaligus memperkuat konservasi sumber daya panas bumi sebagai bagian dari warisan geologi nasional.

Zonasi Kekuatan Batuan Berdasarkan Pengeboran Geoteknik dan Uji Laboratorium di Pit Bara 7 PT Baramulti Suksessarana Site Batuah KM 28 Kecamatan Loa Janan Kabupaten Kutai Kartanegara Provinsi Kalimantan Timur

Mardiana Mardiana — 2025-11-25

Kegiatan penambangan memerlukan data sifat-sifat dan karakteristik batuan. Pendekatan ini memungkinkan untuk melakukan kegiatan eksplorasi seperti kegiatan pengeboran geoteknik. Pengeboran geoteknik merupakan kegiatan pengambilan conto batuan di dalam lapisan tanah untuk mengetahui sifat-sifat dan karakteristik geologi suatu area. Penelitian ini dapat mengetahui terkait analisis zonasi kekuatan batuan berdasarkan pengeboran geoteknik dan uji laboratorium. Analisi ini mencakup beberapa parameter penting terkait litologi batuan, Rock Quality designation (RQD), Geological Strength Index (GSI), kekuatan batuan, daya dukung (bearing capacity). Metode yang digunakan dalam penelitian ini yaitu metode kuantitatif deskriptif dimana menggunakan proses data-data berupa angka untuk menganalisis dan melakukan penelitian, terutama mengenai penelitian yang sudah dilakukan. Pengeboran geoteknik di lokasi penelitian pit bara 7, adapun batuan penyusun utama pada BH-07 dengan kedalaman 70 m setiap lubang bor didominasi oleh organic soil (fat clay), batulumpur (mudstone), dan batubara (coal), dengan ketebalan lapisan batubara bervariasi. Kualitas massa batuan menggunakan nilai RQD menunjukkan variasi yang signifikan. Excavator yang menggunakan crawler track (rantai) terbukti memiliki ground pressure yang jauh lebih rendah, karena beratnya disebar secara merata pada area kontak yang luas. Sebaliknya, dump truck yang menggunakan roda menghasilkan ground pressure yang tinggi, karena seluruh beban yang berat disalurkan ke tanah melalui area kontak yang kecil pada roda-rodanya.

Evaluasi Pengaruh Settling Pond terhadap Kestabilan Lereng Highwall pada Tahap Optimalisasi Penambangan Batubara

Septi Wulandari Wulandari — 2025-11-25

The slope stability analysis of the highwall of PT. X coal mining was conducted to support the optimization plan for the mining of seams M and N, aiming to obtain coal reserves more efficiently without compromising mine safety. This study aims to evaluate the influence of the existing settling pond on the stability of the highwall slope and to determine the feasibility of the proposed slope geometry design. The analysis was carried out using geotechnical data, including physical and mechanical properties of rocks, discontinuity conditions, and rock mass parameters based on the Rock Mass Rating (RMR) system and Hoek–Brown failure criterion. The Safety Factor (SF) and Probability of Failure (PF) were analyzed under dynamic conditions, considering a seismic acceleration of 0.08 g and groundwater level at 80–85% of the total slope height. The results showed that the minimum SF under dynamic conditions was 1.072, with a PF of 2.608%, which remains above the safety threshold according to the Decree of the Ministry of Energy and Mineral Resources (ESDM) No. 1827 K/30/MEM/2018. These findings indicate that the highwall slope is stable, and the presence of the settling pond has no significant impact on its global stability. Therefore, the optimized slope design can be safely applied in future mining operations.

Kinerja Dinamis dan Sistem Kemudi Mobil Daihatsu Ayla Tipe 1.0 MT 2017

Agung Wahyu Saputra — 2025-11-25

Sistem independen yang saling terkait untuk menciptakan prinsip gerakan maupun stabilitas pengendaliannya merupakan sistem penting yang ada pada sarana trasportasi. Sistem penunjang transportasi kususnya pada mobil yang cukup vital adalah sistem kemudi dan sistem kinerja dinamis mesin. Keduanya memiliki peran penting sebagai penunjang stabilitas dan performa dalam operasional mobil. Publikasi ini menjelaskan studi analisis dinamika penggerakan kendaraan, analisis sistem pengereman, serta analisis sistem kemudi (Ackerman). Tujuan dari penelitian ini menganalisis sistem kemudi dan kinerja dinamis mobil yang sangat populer di Indonesia, yaitu Daihatsu Ayla tipe 1.0 MT tahun 2017. Hasil menunjukan bahwa daya puncak mobil 65,8 Ps pada 5920 rpm, torsi puncak 96,47 Nm pada 3600 rpm, waktu yang dibutuhkan untuk mencapai kecepatan maksimal 55,5 m/s adalah 27,053 s. Selain itu karena Daihatsu Ayla adalah mobil berpenggerak depan, distribusi pengereman cenderung di roda depan karena berat mobil cenderung lebih berat di bagian depan. Daihatsu Ayla juga memiliki batas kecepatan aman ketika berbelok, apabila mobil berbelok melewati batas kecepatan, resiko mobil tergelincir dan terguling akan semakin besar.

Studi Protolith pada Komplek Larangan, Desa Pesodongan, Kecamatan Kaliwiro, Kabupaten Wonosobo, Provinsi Jawa Tengah

Fadhilah Elsa Putra — 2025-11-25

Penelitian ini dilakukan di kawasan Komplek Larangan, yang merupakan bagian dari zona Pegunungan Serayu Selatan Jawa Tengah. Kompleks Larangan memiliki umur relatif sama dengan Formasi Karangsambung, menunjukkan kesetaraan dalam sejarah geologinya. Namun secara geologi kurang mendapat perhatian dalam hal studi geologi. Satuan ini tersingkap di atas Kompleks Melange Lok Ulo, yang menandakan bahwa proses pembentukannya terjadi setelah aktivitas tektonik dan pengendapan melange tersebut. Tujuan penelitian adalah untuk mengetahui batuan asal (protolith) dari batuan metamorf yang dijumpai di lokasi penelitian. Metode yang digunakan studi pustaka, pengambilan data geologi dan sampel batuan serta melakukan analisis laboratorium. Hasil penelitian lapangan menunjukkan tersusunnya batuan metamorf berupa sekis mika dan sekis epidot dengan protolith berupa sedimen pelitik

Pengaruh Frame terhadap Kinerja Modul Panel Surya 100 Wp di Iklim Tropis Yogyakarta

Rivan Muhfidin — 2025-11-25

Penelitian ini bertujuan untuk menganalisis pengaruh frame terhadap kinerja termal dan keluaran daya modul fotovoltaik (PV) berkapasitas 100 Wp pada kondisi iklim tropis Yogyakarta. Metode yang digunakan adalah simulasi numerik berbasis model termal-elektrik dengan membandingkan dua konfigurasi modul, yaitu framed (menggunakan aluminium) dan frameless (tanpa frame). Temperatur sel (T_cell) dihitung berdasarkan model empiris Nominal Operating Cell Temperature (NOCT), sedangkan daya keluaran ditentukan menggunakan koreksi suhu terhadap kondisi standar (STC). Hasil simulasi menunjukkan bahwa modul framed memiliki temperatur sel lebih rendah 2–3 °C dibandingkan frameless, dengan daya keluaran 2,3% lebih tinggi. Estimasi energi tahunan mencapai 1.596 kWh/kWp/tahun untuk modul framed dan 1.560 kWh/kWp/tahun untuk frameless. Dengan mempertimbangkan degradasi tahunan (0,5% untuk framed dan 0,7% untuk frameless), total energi kumulatif selama lima tahun menunjukkan selisih 231 kWh. Hal tersebut menunjukkan bahwa desain frame tidak hanya berfungsi struktural, tetapi juga sebagai elemen disipasi panas pasif yang meningkatkan efisiensi dan keandalan modul PV pada kondisi tropis.

Analisis Sifat Mekanik Hasil Cetak 3D dengan Variasi Parameter Fused Deposition Modeling (FDM)

Noesanto Dewantoro Ahmad — 2025-11-25

Teknologi Additive Manufacturing (AM), khususnya 3D Printing (3DP) dengan metode Fused Deposition Modeling (FDM), telah berkembang pesat dan banyak diterapkan di berbagai bidang teknik. Proses ini menggunakan material termoplastik dalam bentuk filamen yang memiliki beberapa keunggulan, antara lain biaya produksi yang rendah, ketersediaan yang luas, kekuatan mekanik yang baik, serta kemampuan mencetak dengan resolusi tinggi. Kualitas dan performa produk hasil cetak sangat dipengaruhi oleh jenis filamen dan parameter pencetakan yang digunakan selama proses fabrikasi. Beberapa parameter penting yang memengaruhi sifat akhir produk antara lain nozzle temperature, bed temperature, infill percentage, infill pattern, printing speed, raster angel, build orientation, layer height dan lain sebagainya. Penelitian eksperimental ini bertujuan untuk menentukan parameter pencetakan optimal pada material filamen termoplastik guna memperoleh performa mekanik terbaik. Fokus penelitian ini adalah pada dua parameter utama, yaitu raster angel dan build orientation. Pengujian tarik dan pengujian impak dilakukan untuk mengevaluasi kekuatan dan ketangguhan sampel hasil cetak 3D. Hasil penelitian menunjukkan bahwa sampel yang dicetak pada orientasi YXZ memiliki kekuatan tarik dan kekuatan impak tertinggi dibandingkan orientasi lainnya. Sampel dengan sudut raster 45° menghasilkan kekuatan tarik tertinggi sebesar 54,36 MPa, sedangkan energi impak tertinggi sebesar 2,73 kJ/m² diperoleh dari sampel dengan sudut raster 0°.

Analytical Hierarchy Process untuk Analisis Kerentanan Tanah Longsor di Desa Banjararum, Kecamatan Kalibawang, Kabupaten Kulon Progo

Iqbal Hidayat — 2025-11-25

Secara administrasi lokasi penelitan berada di Desa Banjararum, Kecamatan Kalibawang, Kabupaten Kulon Progo. Longsor di wilayah Kulon Progo tercatat sebanyak 193 kejadian beberapa diantaranya terjadi di Desa Banjararum dengan tingkat kerawanan yang berbeda. Sehingga perlu adanya kajian yang berfungsi untuk mengetahui wilayah rawan longsor. Penelitian ini bertujuan mengidentifikasi wilayah rawan longsor di Desa Banjararum. Analisa kerawanan longsor dilakukan dengan cara menerapkan pendekatan heuristik dengan menggunakan metode Analytical Hierarchy Process (AHP) dan indeks kerawanan longsor dihitung dengan menggunakan metode weighted overlay. Hasil penelitian menunjukkan bahwa faktor pengontrol dari tingkat kerawanan bencana tanah longsor daerah penelitian adalah parameter kemiringan lereng, semakin dekat dengan kemiringan lereng maka tingkat kerawanan bencana tanah longsor semakin tinggi, pengaruh parameter kemiringan lereng dengan bobot 45,35%. Kemudian parameter curah hujan 27,02%, litologi 13,98%, dan tata guna lahan 13,65%. Faktor pemicu gerakan tanah pada daerah penelitian diindikasikan karena faktor manusia dikarenakan adanya beban tambahaan seperti beban bangunan pada lereng. Tingkat kerawanan bencana tanah longsor didaerah penelitian dibagi menjadi tiga kelas yaitu: kelas dengan tingkat kerawanan rendah,sedang dan tinggi.

Spatial Distribution Patterns of Waste Disposal Sites in the Context of Urban Environmental Services in Yogyakarta City

Ayu Candra Kurniati — 2025-11-25

Rapid urbanization in Yogyakarta City poses serious challenges to municipal solid waste management, exacerbated by the recent regional landfill crisis. Efficiency of municipal solid waste management heavily relies on the spatial distribution of crucial infrastructure, namely Temporary Disposal Sites (TPS). This study aims to (1) map the absolute distribution of TPS and (2) analyze their spatial distribution patterns to identify service concentrations and gaps in Yogyakarta City. This research employs a quantitative approach using spatial analysis methods, specifically Kernel Density Estimation (KDE), with 45 urban villages (kelurahan) as analysis units. Data includes TPS coordinate points from the Environmental Agency and administrative data. The results show that TPS distribution is highly uneven. Kotabaru urban village has 15 units, whereas Muja Muju urban village has none. The KDE analysis confirms the pattern is highly clustered. A primary hotspot (very high density) is identified in the central-northern area (Gondokusuman and Jetis), correlating with the commercial center. Conversely, extensive coldspots (very low density) cover most residential areas in the south (Umbulharjo, Kotagede) and periphery. This finding reveals a significant spatial mismatch between service provision locations (centralized in commercial areas) and service demand locations (dense residential areas). This study concludes that a tangible service gap exists and recommends facility redistribution and prioritizing new TPS development in coldspot zones to enhance environmental service equity.

Karakteristik Mikrostruktur Zona Hancuran dan Inti Sesar Berdasarkan Analisis Petrografi pada Litologi Skis, Bawak, Bayat, Kabupaten Klaten, Provinsi Jawa Tengah

muhamad Hasyim Awaluddin — 2025-11-25

Daerah Bayat, yang terletak di Kabupaten Klaten, Jawa Tengah, mengandung paparan batuan metamorf yang telah mengalami deformasi hebat akibat aktivitas tektonik. Penelitian ini bertujuan untuk mengidentifikasi karakteristik mikrotektonik zona kerusakan dan zona inti menggunakan analisis petrografi pada litologi sekis. Penelitian ini melibatkan pengamatan lapangan, pengambilan sampel, dan analisis mikroskopis sayatan tipis untuk menafsirkan mikrostruktur dan orientasi mineral. Hasil menunjukkan bahwa litologi terdiri dari sekis grafit dan sekis mika dengan foliasi sekistosa dan tekstur kristaloblastik. Di zona inti sesar, mineral mika menunjukkan kain planar yang selaras dengan arah tegangan utama (σ₁), sedangkan di zona kerusakan, orientasi mineral lebih acak dan kurang berkembang. Orientasi foliasi dominan di zona kerusakan adalah N 335°E–N 155°E, sedangkan di zona inti sesar adalah N 290°E–N 110°E, keduanya berarah barat laut–tenggara. Variasi tekstur dan alinyemen mineral ini mencerminkan perbedaan intensitas deformasi antara kedua zona. Secara keseluruhan, fitur mikrotektonik batuan metamorf Bayat merekam arah tegangan regional dan memberikan wawasan tentang sejarah deformasi tektonik di Jawa bagian selatan.

Static Strength Analysis of Bomb Rack Release Mechanism Structures of Mi-35P Helicopter

Andrian Permana — 2025-11-25

The bomb rack release mechanism of the Mi-35P helicopter is a critical structural subsystem that must withstand static loads from the bomb rack or launcher while ensuring a safe and reliable store release. This study investigated the static strength of selected components of the Mi-35P bomb rack release mechanism using CATIA V5 generative structural analysis. The mechanism was modeled using steel F1260-T110/LN668 with a yield strength of 902.52 MPa and an ultimate tensile strength of 1304.73 MPa. A static load of 2500 N was applied to each hook to represent the total launcher load of 5000 N. Von Mises stress analysis was carried out for three main components: the long linkage, short linkage, and hook. The results showed maximum stresses of 1150 MPa, 569 MPa, and 56 MPa, with corresponding margins of safety of 0.134, 2.293, and 22.298. Although all components satisfied the positive margin of safety requirement, the long linkage was identified as the most critical part, indicating that geometric refinement or local reinforcement should be considered in future design improvements.

The Influence of Sedimentation on Sump Capacity and Settling Pond at Pit East PT Unggul Dinamika Utama Kutai Timur Regency East Kalimantan Province

Resti Adillah — 2025-11-25

This research aims to determine the appropriate capacity for sump and settling pond by taking into account the sedimentation that occurs due to erosion carried by runoff water in the pit East of PT. Unggul Dinamik Utama. This analysis was conducted to avoid overflow that could disrupt activities in the mine opening. The results of the analysis show that the total sedimentation in the sump is 0.00000175 m³/day and in the settling pond is 3.10000114 m³/day. With this sedimentation calculation, the appropriate capacity for the sump is 85,523.79 m³ and the settling pond is 174,681.03 m³. Then from the sedimentation, mud material will be dredged referring to the technical instructions of Ministerial Decree No. 18227 K/30/MEM/2018 so that in the sump, dredging of settled mud material is carried out every 81 days, for settling pond in compartment 1 every 155 days, in compartment 2 every 62 days, in compartment 3 every 37 days, in compartment 4 every 49 days, in compartment 5 every 32 days, in compartment 6 every 18 days and retention pond every 6 days.

ANALYSIS OF LIMESTONE QUALITY AS THE MAIN RAW MATERIAL FOR CEMENT PRODUCTION AT PT INDOCEMENT TUNGGAL PRAKARSA TBK. PALIMANAN DISTRICT CIREBON REGENCY WEST JAVA PROVINCE

Jumryatin — 2025-11-25

There are high and low limestone contents found in the limestone quarry at PT Indocement Tunggal Prakarsa. Therefore, to obtain good quality raw materials, it is necessary to carry out a geochemical analysis using X-Ray Diffraction (XRD) and X-Ray Fluorescence (XRF) methods to determine the elemental content contained in the limestone, with the aim of identifying the chemical composition of each limestone sample that will be used for cement production. Based on the research and data analysis conducted, it was concluded that the lithology of rock samples 1 to 15 varies, namely samples 1, 6, 9, and 10 are mudstone, samples 2, 3, 11, and 13 are packstone, samples 5, 12, 14, and 15 are wackestone, and samples 4, 7, and 8 are boundstone. The limestone samples 9 and 1 have low CaO, SiO₂, and Al₂O₃ contents; therefore, it is recommended to perform blending of limestone that meets the required standard composition, where for CaO content of 29.93%, blending between samples 9 and 14 resulted in 62.75%; for CaO content of 47.45%, blending between samples 1 and 14 resulted in 64.51%; for SiO₂ content of 24.1%, blending between samples 1 and 12 resulted in 12.95%; for SiO₂ content of 49.09%, blending between samples 9 and 12 resulted in 15.45%; and for Al₂O₃ content of 18.04%, blending between samples 9 and 8 resulted in 5.87%. Samples 2, 4, and 12 belong to Portland Cement Type I; samples 3 and 11 belong to Portland Cement Type III; samples 3, 5, 7, and 14 belong to Portland Cement Type IV; and samples 13 and 10 belong to Portland Cement Type V. Sample 6, based on its results, can be classified into three types: Portland Cement Type I, III, and V; sample 9 can be classified into two types: Portland Cement Type IV and V; and sample 1 can be classified into two types: Portland Cement Type I and III.