bluuebunny/crossref_metadata_2025 huggingface dataset:
The validity of physics learning evaluation teaching material based on project-based learning and portfolio assessment
Authors: Dewi W S , Murtiani  , Sari S Y , Mairizwan
Published: July 2022

Physics Learning Evaluation course aims to develop students’ knowledge and skills in conducting school assessments in case studies or project assignments. However, the difficulty of implementing a contextual evaluation to actual conditions was the main problem for students. In addition, it was not easy to find evaluations that could be uses as project assignments. On the teacher’s side, the project assignments produced by students had not been thoroughly assessing by appropriate assessments taking into the preparation, process, and results stages. Project-Based Learning (PjBL) is a suitable model for students’ independence in constructing learning through project assignments. The study aims to develop teaching materials for the Physics Learning Evaluation based on PjBL and portfolio assessment. The study used the ADDIE model with five stages: analyze, design, develop, implement, and evaluate. The validation of these teaching materials is part of the development stage, which carry out after the teaching materials create. The results of expert validation of the teaching materials reach 87.41 with very valid criteria. It showed that physics learning evaluation teaching material based on project-based learning and portfolio assessment are appropriate to improve students’ scientific skills.
Development and usability of JUQUANJI game in quantum theory of light among pre-service physics teacher
Authors: Sajri Nur Aqilah Aisyah , Mohtar Lilia Ellany , Ramly Rosazley
Published: July 2022

This study aimed to develop a teaching aid namely ‘JUQUANJI’ and evaluate its usability among physics trainee teachers at Sultan Idris Education University. ‘JUQUANJI’ is adapted from the JUMANJI board game and developed by using Genialy website tool. This study uses a development research design by applying the ADDIE model, which has five phases: analysis, design, development, implementation and evaluation. The research samples consisted of 32 trainee physics teachers from semesters seven and eight selected using a simple random sampling technique. Two research instruments were used, namely the expert validation form and usability questionnaires adapted from the USE Questionnaire. Data from the usability questionnaire were analyzed descriptively using Statistical Package for Social Science (SPSS) version 26.0 to obtain the mean and standard deviation (s.d). The data analyses from two experts showed that the developed game had a very satisfactory validity with 99.48% of agreement. The usability data analyses showed that the ‘JUQUANJI’ game was at a good level with a mean score of 3.79 (s.d = 0.353). The three constructs that represent usability namely usefulness, ease of use, ease of learning and satisfaction are at a good level with the mean score of 3.71 (s.d = 0.385), 3.73 (s.d = 0.391), 3.83 (s.d = 0.333) and 3.89 (s.d = 0.304) respectively. In conclusion, ‘JUQUANJI’ game has achieved the research objectives which is proven through the findings from the validity of experts and usability. This game suitable to help teachers to assess students while the student can make a revision related to the subtopic of Quantum Theory of Light.
Development of Interactive Ludo Games on Earth and Space Science Learning Material as High School Exercise Media
Authors: Haeruman Leny Dhianti , Serevina Vina , Griselda  , Susanti Yuli Eri
Published: July 2022

Enrichment was specific activity given to the students who reached the minimal proficiency criteria. One of the methods that we’re able to attract student’s motivation to learn something is by combining learning and playing (edutainment). Application of media that applied edutainment to the enrichment processed can increase student’s motivation to develop their knowledge. This research was designed to know the media development process, feasibility, practicality, and the student’s response to interactive ludo game which developed as enrichment media. The method used is Research and Development (R & D) with ADDIE Model (Analysis, Design, Development, Implementation, and Evaluation). The subjects were matter expert, media specialist, and 20 students of XI grade Indonesia Maju Senior High School have obtained on earth and space sciences learning material. The data collection instruments in this research are using study papers of specialist material and media, a paper of practicality test, and student questionnaire responses. The result of the research showed validation specialist material given a score of 82,7%, a media expert validation of 80,2%, a practicality validation of 83,4%, and student’s response amounted to 85,6%. Overall obtained a score of 82,9% so it can be categorized as very worthy and excellent.
The Validity of Learning Implementation Plan of Independent Learning in Online Learning using Direct Learning Models on Thermodynamics Subject
Authors: Sunaryo  , Serevina Vina , Anjani Putri , Anggraini Dewi
Published: July 2022

One of the developments of online learning device needed to implement distance learning at home is to prepare a Learning Implementation Plan (RPP) for independent learning with a direct learning model to activate students. This study aims to know the validity of RPP of independent learning on Thermodynamics subjects using the direct learning model. The type of this research is research and development, which refers to the 4-D model are defines, designs, develops, and disseminates. The research instrument used in this search was a validation sheet for experts with validation tests in the form of filling out validity questionnaires then analyzed with a Likert scale. The results of the validity test in the research as a whole obtained a percentage of validity from media experts (88%), material experts (91%), and learning experts (92%) with interpretation of the Likert scale included in the criteria very feasible to use. Based on the results of research and discussion, it can be concluded that the development of RPP of independent learning on Thermodynamics subject using the direct learning model can be applied in physics learning conducted online.
The Development E-Learning Assisted by Flashcard to Improve Students Scientific Literacy in High School on the Kinetic Theory of Gases Materials
Authors: Made Astra I , Halimah Shaladsha Irma
Published: July 2022

Since the outbreak of the pandemic, it requires educators and students at all levels of education to be able to adapt to virtual learning. Based on the needs analysis that the researchers conducted through an online questionnaire for science class of XI students, their obstacle during distance learning was that 64% of students still had difficulty understanding physics material. Students have difficulty analyzing problems in physics problems because there are too many formulas that must be understood, as well as learning factors for students who are less effective. Most of them are interested in interactive learning methods by emphasizing audiovisual, as well as animations and learning videos. Therefore, the study aims to develop e-learning assisted by flashcards to improve the scientific literacy in high school students, because it is easily accessible on any device, can be via a laptop or smartphone. The average validation results by media experts are 89.58%, material experts are 90.65%, learning experts are 94.15% and by class XI physics teachers are 96.00%. The average value of the overall validation test by experts is 92.6% with the interpretation of “very feasible” as a learning medium with an N-Gain of 0.44 on a medium increase interpretation.
The Developing of Digital Pedagogical Curriculum of Primary Education Teachers in Indonesia
Authors: Bentri A , Hidayati A
Published: July 2022

Digital pedagogical competence is an ability that needs to be developed by teachers to instruct their students in the 4.0 industrial revolution era of the 21st-century. In West Sumatra, the creative capabilities of instructors are inadequate. Hence, they must be able to apply different approaches to learning. This research aims to develop the curriculum of digital pedagogical competence of primary education teachers in West Sumatra. The method of this research is research and development by using Borg n Gall Model.The results of this study, have found curriculum objectives, teaching materials or materials, learning experiences and evaluation tools used for the development of teacher digital pedagogy competencies. However, for these, it is recommended to provide structured training for the development of digital pedagogy abilities.
SIMSPEC-G: a simple code for the simulation of HPGe detectors for gamma rays up to 1 MeV
Authors: Nayak S.S. , Mukherjee G.
Published: July 2022

A new program called SIMSPEC-G has been developed to
simulate the interaction of gamma-rays of energies upto 1 MeV with
different materials. In this work, 3 different geometries of high
purity Ge (HPGe) detectors have been studied: single crystal HPGe,
segmented single crystal HPGe and clover geometry composed of four
HPGe crystals in clover-leaf arrangement. Contributions of different
processes to peak formation have also been examined. The simulated
spectrum, for a single crystal of clover, and for 662 keV gamma-ray
(from 137Cs source) has been compared with experimentally
obtained spectrum. The addback factor (gain in full energy peak
efficiency due to the addition of the energies of the Compton
scattered gamma rays in more than one crystal of a clover HPGe
detector) and the hit pattern for a range of gamma-ray energies from
the experiment have been excellently reproduced by the simulation
leading to its validation. The fraction of total events in which
highest or full energy is deposited in the first hit crystal is
estimated and the use of this idea to improve angular resolution of
a Clover detector has been explored.
Simulations of recoil trajectories in Dubna Gas-Filled Recoil Separator 2 by GEANT4 toolkit
Authors: Solovyev D.I. , Kovrizhnykh N.D.
Published: July 2022

Dubna Gas-Filled Recoil Separator (DGFRS-2) is a new
facility at the Super Heavy Element Factory which allows us to study
the properties of superheavy elements (SHEs) formed in complete
fusion reactions in the femtobarn cross-section range. High
dispersion and complex magnetic configuration make it difficult to
tune the separator and find the optimal current values in the
magnetic elements. This work presents a simulation model of the
DGFRS-2 based on a GEANT4 toolkit. The main methods of trajectory
simulations of heavy ions in gaseous media are discussed and several
new processes are implemented in GEANT4. Calculation results agreed
well with the data produced in test experiments which allows us to
use this model for transmission determination and tuning of the
separator in experiments aimed at SHE investigations.
Backlash to fossil fuel phase-outs: the case of coal mining in US presidential elections
Authors: Egli Florian , Schmid Nicolas , Schmidt Tobias S
Published: July 2022

Phasing out coal is a crucial lever in reaching international climate targets. However, the resulting jobs losses might trigger voter backlash, making phase-outs politically costly. Here, we present an analysis of the electoral response to coal mining job losses in US presidential elections using matched and bordering difference-in-difference estimators. Our findings confirm that fossil fuel phase-outs can result in voter backlash. In our main specification, we find a four percentage-point (pp) increase in the Republican vote share in 2012 (range across specs. = 3.6 pp–4.5 pp), declining to 3.2 pp in 2016 (range across specs. = 3.2 pp–4.2 pp), in counties suffering from coal mining job loss. The estimated electoral response is around three times as large as the number of jobs lost. We observe this response only in places where there was significant job loss, where these jobs accounted for a large share of locally available jobs and where income levels were low. Relative party strengths do not influence the results.
Sinking seaweed in the deep ocean for carbon neutrality is ahead of science and beyond the ethics
Authors: Ricart Aurora M , Krause-Jensen Dorte , Hancke Kasper , Price Nichole N , Masqué Pere , Duarte Carlos M
Published: July 2022

Sinking vast amounts of seaweed in the deep ocean is currently being proposed as a promising ocean carbon dioxide removal strategy as well as a natural-based solution to mitigate climate change. Still, marketable carbon offsets through large-scale seaweed sinking in the deep ocean lack documentation and could involve unintended environmental and social consequences. Managing the risks requires a number of urgent actions.
Soils, Science and Community ActioN (SoilSCAN): a citizen science tool to empower community-led land management change in East Africa
Authors: Kelly C , Wynants M , Patrick A , Taylor A , Mkilema F , Nasseri M , Lewin S , Munishi L , Mtei K , Ndakidemi P , Blake W
Published: July 2022

Pastoralist communities worldwide face complex challenges regarding food and feed productivity. Primary production systems are under stress, nutritional choices are changing and the relationship between development and agriculture is undergoing profound transformation. Under increasing pressure from climate and land use change, East African agro-pastoral systems are approaching a tipping point in terms of land degradation. There is an urgent need for evidence-led sustainable land management interventions to reverse degradation of natural resources that support food and water security. A key barrier, however, is a lack of high spatial resolution soil health data wherein collecting such information for each individual community is beyond their means. In this context, we tested whether bridging such data gaps could be achieved through a coordinated programme at the boundary between participation and citizen science. Key outputs included a community-led trial of a hand-held soil scanner, which highlighted a range of positive benefits and practical challenges in using this technology in this context, with identification of some potential solutions; and a targeted soil organic matter and nutrient status dataset in a small catchment-based community setting. The results show that if the practical challenges can be resolved, use of portable soil scanner technology has the potential to fill key knowledge gaps and thereby improve resilience to the threat of land degradation through locally responsive farmer and community decision-making.
Sensing the Terrestrial and Atmospheric Hydrological Dynamic using Satellite Gravimeter and GNSS
Authors: Bramanto Brian , Sarsito Dina A. , Gumilar Irwan , Kuntjoro Wedyanto
Published: July 2022

Geodetic observation methods, e.g., satellite gravimeter and Global Navigation Satellite System (GNSS), are mainly used for determining the Earth’s gravity field and reference system. However, many efforts have been made to adopt the mentioned methods for estimating hydrological dynamics. The satellite gravimeter of the Gravity Recovery and Climate Experiment and its Following-On missions (GRACE/GRACE-FO) have proven to capture the terrestrial hydrological variation. Also, thanks to its signal propagation through the atmosphere medium, GNSS can be used for sensing the hydrology variation in the atmosphere, i.e., troposphere medium. This study aims to explore GRACE/GRACE-FO and GNSS observations to estimate the respective terrestrial and atmospheric hydrological variation in Bandung, Indonesia. Monthly solutions of GRACE/GRACE-FO provided by three agencies were used to estimate the terrestrial hydrological variation. We also used the continuous GNSS site of ITB1 and calculated the atmospheric hydrological series in the form of precipitable water vapor. We found that the terrestrial hydrological series varies approximately ±20 cm, while the precipitable water vapor ranges between 1 to 5 centimeters. Further, we observed long-wavelength components from terrestrial and atmospheric hydrological variations that correspond to dry and wet seasons. However, we only sensed shorter wavelength components of hydrological dynamic from GNSS observation and not for the GRACE as the estimated hydrological variations were estimated monthly. At the same time, delays were calculated every two hours using GNSS observations. Nevertheless, this study shows the potential uses of geodetic approaches such as satellite gravity and GNSS observations to capture the hydrological dynamic.
Utilization of Terrestrial Laser Scanner Technology for Analyzing Shape of Dutch Cave (Bandung, West Java)
Authors: Jessy Kartini G A , Rizky A , Rafiq F A
Published: July 2022

Technological developments in the field of surveying and mapping remain in progress. One technology that provides precise and accurate results is the terrestrial laser scanner (TLS). This technology can generate millions of points in a short time and represent objects in 3D. TLS technology has become famous for heritage documentation purposes due to its ability to obtain detailed geometry and information from maintaining historic buildings. This research is in the Dutch Cave, Djuanda Forest Park, Bandung, West Java, to map and document 3D. To produce accurate data, frame measurements were carried out using a total station, GNSS, which ended with acquisition using TLS. The registration method used is the target-to-target method. The goal of this research is to create as-built drawings of the Dutch Cave in analyzing the Dutch Cave's form in greater detail. This investigation determined that the Dutch Cave measures 124.435 meters in length and has a height difference of 69.7 cm between the entrance and the exit. The as-built drawing of the Dutch Cave illustrates that the shape of the cave varies from entrance to exit. There is a cave chamber that widens by 18.8 cm toward the cave's center and narrows by 20.7--32 cm toward the cave's exit. The Dutch Cave has a slope of between 1 and 5 degrees. The Dutch Cave 3D data can be used for a documentation archive for the Djuanda Forest Park.
Interaction of Air and Sea above Seamount in the Halmahera Sea
Authors: Sobaruddin D P , Marpaung F. , Putra R.A.B. , Fahim A. , Dharma C.S. , Pramono D.T. , Kristiawan A.
Published: July 2022

The interaction of sea and air plays a very important role in the early stages of cloud formation. In certain cases, changes in temperature in the sea surface layer and the atmospheric layer closest to the sea will affect the initiation of the formation of water vapor which can become cloud. To monitor the sea-air temperature interaction above Seamount in Halmahera Sea, we took an expedition of Jala Citra-I 2021 Aurora from August 28 to September 9, 2021 using The Indonesian Navy Center for Hydrography and Oceanography research vessel, the Navy’s KRI Spica-934. Weather condition was observed using two installed Automatic Weather Stations (AWS) mounted on a vessel, radiosonde in Sorong, West Papua, and Outgoing Longwave Radiation (OLR) data from NOAA (National Oceanic and Atmospheric Administration), while the profile of sea surface temperature (SST) were observed using a 24-hour CTD measurement. Both AWS data were analyzed using two samples Kolmogorov-Smirnov test with h=1 and showed low correlations (r2= 0.2-0.4, p-value <0.01) for the parameters of temperature, relative humidity, and wind speed. The hourly SST ranged 29°C – 30°C from 0-50 meter and the Lifting Condensation Level ranged about 939 to 985 mb in the morning on 1 - 2 September. The OLR was a neutral and positive values. These conditions indicated that a strong local effect dominantly created by a strong sea-air interaction in the study area. A warm SST with a strong divergence wind leads a warm air layer developed on the sea surface to rise. A low OLR with a moderate CAPE is enough to support the updraft of water vapor, rising from sea surface and then support convective activity formed in the region. In addition, it shows that the changes activity of convective clouds, developing over warm waters, are dominant mode of diurnal variability. However, investigation of intra-seasonal variability in Halmahera Sea was not clear. Further investigation on spatiotemporal of sea-air interaction on a local scale are needed to capture the phenomena on its season.
Clastic Sediment Characteristics of Gumai Formation: Preliminary Study of Tertiary Rocks in South Sumatra Basin
Authors: Hendrizan M
Published: July 2022

The depositional environment of Gumai formation is still challenging to be studied. Previous studies of the depositional environment in the Gumai Formation show a debate interpretation of transition, shallow marine, and deep marine environment. The study's objectives are to identify lithology characteristics of Gumai Formation in Baturaja region and determine the potential environment of the Gumai Formation. Miocene clastic sedimentary rocks of Gumai Formation show well-preserved features in Simpang and Muara Dua, South Sumatra. The Gumai Formation discovered in the southern anticline flange, particularly in Muara Dua, composes marl with quartz veins. The opposite flange in the northern part of Simpang region indicates Gumai Formation consists of siltstone, calcareous sandstone, quartz sandstone and sand ball in siltstone layers. Based on the obtained data at Muara Dua and Simpang, the Tertiary rocks of the Gumai Formation are situated in the flange of folded Pre-Tertiary rocks at Garba complex. Gumai Formation in the research area was deposited in transition environment to shallow sea in which the formation in Simpang has shallower marine environment than Muara Dua region.
Geochemistry of Gede Volcanic Complex West Java, Indonesia, Compared to Salak Volcano as its Proximity and how The Ciletuh Mélange Complex Lineament Affected It
Authors: Winanto Erza , Abrory Achmad Nazar , Edwin Eric , Abdurrachman Mirzam
Published: July 2022

‘Mélange’ has been used to indicate a larger spectrum of chaotic rock bodies formed in various and different tectonic settings (rift–drift cycles, oceanic subduction, continental collision, and intracontinental deformation) by tectonic, sedimentary, and diapiric processes and their mutual interaction. Two well-known mélanges in Java Island are Ciletuh mélange in Sukabumi and another in Karangsambung, Kebumen. Previous studies suggest those mélanges are connected and indicate the Early Cretaceous Sundaland boundary elongated from Ciletuh, Karangsambung, and up until Meratus in Southeast Kalimantan. The Gede Volcanic Complex (GVC) and Salak Volcano of the Sunda island arc (West Java, Indonesia) are Quaternary volcanoes that lie geographically on the Early Cretaceous Sundaland boundary. An indication of crustal assimilation related to the Ciletuh Mélange complex has been observed by previous research. Therefore, this research intended to further investigate whether GVC and Salak are affected by that boundary through an igneous petrogenetic approach.

This research uses geochemical data (major and trace elements) proceeded by various discrimination diagrams to account for the tectonic conditions of the Gede Volcanic Complex and Salak Volcano. Products from both GVC and Salak are all sub-alkalis rocks that came from active continental plate margins. Geochemical analysis shows that one metabasalt sample from Ciletuh Mélange Complex has the same characteristics to anomalies found at GVC by being an island arc tholeiite. Meanwhile, anomalies at Salak could be explained by its location being on top of the Meratus lineament that might contain granitic deposits.
Morphometry Analysis of Sedayu Mountainous Catchment Areas from Detailed Aerial Photos
Authors: Tutur  , Army Edo Kharisma , Rohman Arif
Published: July 2022

Morphometric analysis is a powerful tool to understand the hydrological process quantitatively and the main requirement to determine the hydrological characteristics of a watershed. Morphometric analysis to determine the drainage characteristics of the Sedayu River Sub-watershed, Semaka District, Tanggamus Regency, Lampung Province was carried out using Digital Elevation Model (DEM) data. The primary data used is aerial photography using drones, the location of aerial photos representing watersheds of concern. The catchment area morphometrics were obtained from the extraction of the morphometric characteristics of the combined DEM data from the mountain watershed and the analysis of topographic maps by using ArcGIS software. Based on reports over a period of time, at several points in the area there are frequent river floods that overflow during heavy rains. Morphometric analysis in flood-prone areas with high rainfall is needed. The morphology of the Sedayu area has contrasting variations consisting of several gentle alluvial plains, some of which are Bukit Barisan hills with varying slope variations. The Sedayu watershed in this study is divided into 3 sub-watersheds, namely: sub-watershed A, sub-watershed B, and sub-watershed C. However, only sub-watershed A is the focus of morphometric analysis because its longest river, record flood disasters, landslide records, and has upstream to residential. Morphometric analysis was carried out on parameters such as watershed area (A), watershed length (Lb), main river length (Ln
), watershed width (W), drainage density (Dd
), bifurcation ratio (Rb
), and circularity ratio (Rc
). The results of morphometric calculations are the length of the watershed 4.82 km, the length of the main river is Sub-watershed A 8.996 km, the width of the watershed 0.686 km, and watershed area 4.861 km2 Based on these results can be calculated drainage density (Dd
) 2.719 km/km2 which means Sub-watershed A of a rough type with the inundated surface, permeable sub-soil, and resistant to erosion. Bifurcation ratio (Rb
) is 3.333 which means sub-watershed A has a rapid rise and fall in floodwater. Then, the circularity Ratio (Rc
) 0.32 which means Sub-watershed A is elongated so that the peak discharge and decrease flow quickly and causes a link with the hydrological response of rainfall-runoff. The results of this morphometric characteristic analysis are the right reference for planning strategies for soil erosion control and soil conservation.
The Application of Electrical Resistivity Tomography using Wenner-Schlumberger Arrays Configuration to Identify the Geological Structure in Kancah Warm Spring, West Java Indonesia
Authors: Tongkeles Patriks Vero , Suryantini  , Pratama Angga Bakti
Published: July 2022

Kancah warm spring is located in the southern part of Tangkuban Perahu Volcano, in West Java Indonesia. This warm spring has a temperature 470 C and a pH of 3 and it is used as a source of water for nearby tourist attractions. This warm spring has a large discharge, with the source thought to be from subsurface water associated with Tangkuban Perahu Volcanic complex. Knowing the source and geological control of this warm spring is one way to further identify the Tangkuban Perahu geothermal system, especially its permeability. For that reason, this research aims to using Electrical Resistivity Tomography (ERT) method to identify the geological structure that controls the appearance of geothermal manifestation using the resistivity method with Wenner – Schlumberger arrays configuration. The study starts with lineament study using DEM to identify the structure in surface and then determine the geometry of subsurface geological structures are using the electrical resistivity tomography (ERT) method using the Wenner - Schlumberger configuration. with a length 320 meters of each line and the electrode spacing is 10 m. The results of the interpretation of satellite images show that there is a lineament which is interpreted as a fault structure with a NE-SW direction that is right at the location of the discharge of the warm spring. There are 3 - 4 faults identified in each profile, some of the faults identified beneath the Kancah spring and may controlled the warm spring. These faults are a permeable that flows hydrothermal fluids from the subsurface to the surface in the form of warm spring..The lithology beneath of Kancah warm spring are dominated by breccia pyroclastics, clays, and a small amount of andesite igneous rocks.
The Significances of Cretaceous Petrified Wood Fossils from Padangcermin, Lampung in Paleoenvironmental Perspectives
Authors: Harbowo D G , Nahar R N F A , Sari D , Julian T , Kuswara T A , Abimayu R A , Lajona R A , Huzaifah S
Published: July 2022

Reports on the presences of petrified wood fossils in Padangcermin, Lampung, are rare, no strong examination that expose the scientific concern on its paleoenvironment perspective. By the published geological map, these fossils was found in the area that labelled as Cretaceous sedimentary rock (145-66 mya). Recently, the known oldest petrified wood fossil in Indonesia, is from Miocene epoch (23.03-5.33 mya). It is an interesting circumstance to examine. By this study, we are trying to confirm this circumstances by conducting the geological mapping, collecting, and identifying the petrified wood fossils that could be found as in situ fossils in the area. This study reveals a new update in paleoenvironmental perspective. The petrified woods in this area are commonly preserved in cherty layer. There are also several fossilized aquatic freshwater plant remains that presences in this area. We suggest the fossilization of the petrified wood fossil in this area is related to high alkaline-freshwater lacustrine. Supposedly, it associated with the Cretaceous terrestrial landmass and freshwater lacustrine environment in southern paleo-Sumatra by paleontological interpretation of data in this study.
Mapping the distribution of natural ecosystems on peatlands through vegetation using the object-based image analysis (obia) method in bangko district, rokan hilir regency, riau.
Authors: Roganda M.S. , Murti Sigit Heru , Widyatmanti Wirastuti
Published: July 2022

Expansion of the use of natural ecosystems on peatlands is increasing rapidly in Bangko District, Rokan Hilir Regency, Riau. This utilization tends to cause damage to the natural ecosystem of peatlands which has a major impact on the local environment (in situ) and the surrounding environment (ex situ), so a mapping is needed to detect the presence and ensure the distribution of the natural ecosystem of peatlands. This study aims to (1) map the distribution of natural ecosystems on peatlands through vegetation objects using Sentinel 2A and SPOT 7 using the OBIA method, (2) Compare the accuracy of Sentinel 2A and SPOT 7 in recognizing endemic vegetation types in natural ecosystems on peatlands with using the OBIA method. OBIA is used to detect the presence of peatlands, the detection is carried out through stretched endemic vegetation objects that grow in the natural ecosystem of peatlands. OBIA is carried out in three steps, namely Segmentation, Classification and Accuracy Test. In the classification process, building a ruleset is the key to interpreting the natural ecosystem of peatlands. The results obtained are (1) Sentinel 2A produces a more dominant distribution on the East, North and West edges while in the middle it tends to be less, the total area of natural peatland ecosystems in Sentinel 2A is 94,994 KM2. In the SPOT 7, the distribution of natural ecosystems of peatlands is more dominant in the eastern part while the western part tends to be small, the total distribution of natural ecosystems of peatlands in the SPOT 7 image is 281,443 KM2. (2) The accuracy rate of Sentinel 2A is 81.395% with an accuracy of 35 samples from a total of 43 samples of accuracy tests and SPOT 7 of 88.372% with an accuracy of 38 samples from a total of 43 samples of accuracy tests carried out.
Seismic Noise Analysis in InaTEWS Earthquake Station Network (Case Study: Flores Earthquake 7.4, 14 December 2021)
Authors: Hakim Arif Rachman , Saputro Adhi Harmoko , Rohadi Supriyanto , Gunawan Mohamad Taufik , Kardoso Ricko
Published: July 2022

Meteorological, Climatology and Geophysics Agency (BMKG) is the agency responsible for providing information on earthquake parameters in Indonesia. BMKG has installed 411 seismometers network spread across Indonesia, this network is known as the Indonesia Tsunami Early Warning System (InaTEWS) network. The dense distribution of the seismometer is expected to be able to provide accurate earthquake parameter results. However, the accuracy of earthquake parameters does not only depend on many stations but also on the quality of the data recorded by the seismometer. In this study, an analysis of 15 data quality was carried out at the nearest station that recorded the Flores earthquake on December 14, 2021. Analysis of data quality using the power spectral density (PSD) and probability density functions (PDFs) methods, where good data quality can be seen in the spectrum of the seismograph recordings that are between the Peterson’s new high noise model (NHNM) and new low noise model (NLNM).
Analysis of Exploration Wells on Aquifer in Kaliwungu Formation and Regional Planning Recommendations
Authors: Darul Achmad , Kurniawan Rizki , Irawan Dasapta Erwin , Wibowo Dimas Maulana
Published: July 2022

Infrastructure development in the northern coast of Java continues to take place. The study and support of subsurface geological data and the value of hydrogeological parameters is one of the important parameters to support sustainable development. The existence of well exploration reportedly can support researchers for model validation and calibration. We carried out One-Dimensional and Two-Dimensional geoelectrical acquisition along with drilling in the Kaliwungu Formation which was lined with the Halang Formation. Ten points of one dimensional geoelectrical and two lines of geoelectrical acquisition VES method (Vertical Electrical Sounding), with a depth range of 100m Schlumberger and Wenner-Schlumberger configurations for profiling have reflected the study area dominated by aquitard (silty clay) with resistivity values < 20 ohm.m. The result of VES was then followed up by analysing the value of the well logging resistivity which was compared with the lithology of the cutting results in the 108m deep drill hole. Value of hydrogeological properties was carried out by the pumping test, were pumping test analysed using pumping cooper – Jacob single well software, and the result of hydraulic conductivity value was 6 x 10-9m/s, and the transmittivity value was 5.6 x 10-7 m2/s. Based on the Farvolden Method, the safe yield value was found to be comparable to the value according to Johson which is 3-8%.
Monitoring CO and O3 concentration that caused climate change periodically using Google Earth Engine (study case: Java Island)
Authors: Ikram N M , Afifah L , Arthatia B S , Wicaksono S J , Maharani M , Ediyanto  , Ihsanudin T , Apriyanti D
Published: July 2022

Climate change is the change of temperature and weather pattern in long terms caused by the accumulation of greenhouse emission in the atmosphere. Those emissions act like a blanket covering earth, trapping heat and causing the increase of earth’s temperature. The emissions of greenhouse gases causing climate change are CO2, O3, N2O, CH3, et cetera. The existence of these gases have to be observed periodically for monitoring and controlling purposes. These days, remote sensing is capable of doing that. Sentinel-5P imagery exists as an imagery that can observe gas concentration within the earth’s atmosphere. This research is aimed to observe CO and O3 gas, which cause climate change, using Sentinel-5P satellite imagery using Google Earth Engine (GEE) periodically. GEE is a platform allowing its users to access and process data freely. The result of this research shows that there is a change in CO and O3 concentration throughout January to November 2021. The highest concentration for CO was in October, and the lowest was in July. Meanwhile, the highest concentration for O3 was in October, and the lowest was in June. Based on the research done, Sentinel-5P satellite imagery succeeded in monitoring CO and O3 concentration periodically every month.
Love Wave Dispersion Analysis from Ambient Seismic Noise in Banyumas Basin, Central Java, Indonesia
Authors: Kusuma A H , Zulfakriza  , Nugraha A D , Rosalia S , Setiawan A , Marjiono
Published: July 2022

The Banyumas Basin is one of a sedimentary basins in the southern coast of Central Java that has many manifestations of the presence of hydrocarbons in the form of oil and gas seeps found on the surface. Its presence is covered by a thick subvulcanic sedimentary layer. A conventional seismic active method which is usually used to delineate subsurface structures in an hydrocarbon area, however it can be challenging to imaged the structures beneath surface in areas covered by thick sub-volcanic sediments. Another method is needed to investigate the subsurface image in a thick sub-volcanic area, such as Banyumas basin. We cross correlated of the ambient seismic noise at transversal component to retrieve the love wave empirical Green's function. We used 40 broad band seismic stations for 60 days recording from Center for Geological Survey - Indonesian Geological Agency. The daily cross-correlated data then stacked to obtain the Love waves Green’s function. The Green’s function is clearly seen in 1-10 s period band. Then, the obtained Green’s function will be analyzed to get the Love waves group velocity.
Warming trend during Medieval Climate Anomaly in Tropical Maritim Indonesia: Records from Porites Corals
Authors: Cahyarini S.Y. , Hendrizan M. , Utami D.A.
Published: July 2022

A period that lasted from 900-1300 AD has been known as the Medieval Climate Anomaly. This period has been indicated as the warming period of the earth’s temperature. However, this warming phenomenon is still the subject of debate today, whether global or regional warming. Several studies concluded that the Medieval warm period is a global phenomenon and an important warm period, although external forcing is mainly similar to the present day. Several climate archives from Indonesia i.e. lake sediment, marine sediment and speleothem show a warming trend during this period. In this study, the seasonal warming trend during the Medieval climate is resolved from Porites coral from Lampung Bay, Indonesia. However, the seasonal temperature magnitude during the Medieval period is lower than today. This study confirms the coral medieval climate records from Mentawai islands. The result suggests that a warming trend occurred in Indonesia during the Medieval climate anomaly.
Characterization Of Sedimentary Process In An Estuarine Environment Based On Grain Size Trend Analysis And Geochemical Trace Element In The West Flood Canal River, Semarang
Authors: Devienna S N , Nugroho S H , Kurniasih A , Putra P S , Lestari  , Awibowo S P , Kaisupy M T , Amar  , Jakah
Published: July 2022

The West Flood Canal River is one of the major rivers that flows the central of Semarang Bay. The west flood canal river is located in the middle of a densely populated residential and used as city drainage in the Semarang. Unfortunately, the upper part of the river has been swallowed up. This river has unique sedimentation dynamics, so it becomes a suitable research object to determine the relationship between river sedimentation processes and the concentration of trace elements contained in the sediment. A core sample was taken at the mouth of the west canal flood river for research purposes. The analysis included grain-size trend analysis (GSTA) and geochemical trace elements on 40 sub-samples of sediment core slices within 1 cm intervals. Afterward, the GSTA results were grouped by clustering to obtain lithofacies. Each lithofacies has geochemical characteristics that indicate changes in environmental conditions over a period of time. The GSTA showed that the sediment core is dominated by coarse silt to fine silt. The cluster showed there are at least 5 lithofacies, which have different sedimentary characteristics. In general, the character of the sediment which is dominated by coarser grain size has a higher concentration of Fe, Ca, Mn, Ti, and lower levels of K. On the other hand, the sediment group which has a sedimentary character dominated by fine grain size has a lower content of Fe, Ca, Mn, Ti, and higher K levels.
The Relationship of Lithology with Landslide Occurrences in Banyumanik and Tembalang Districts, Semarang City
Authors: Trisnawati D , Najib  , Hidayatillah A S
Published: July 2022

Movement of soil and rock masses down the slope or known as landslide is a natural activity that can pose a danger to humans. Generally, landslide can be influenced by the slope, slope materials (rock/soil), and rainfall. Morphologically, the study area, which is located in the borders of Tembalang and Banyumanik Districts, Semarang City, is a hill that is quite steep. It has a potential to experience landslides. Landslide occurences at the study area do not always occur on steep slopes. Therefore, the aim of this study is to determine the relationship between the slope materials and the occurrences of landslide. Data was obtained through mapping to determine geological conditions and enlisting landslide occurrences at the study area. Furthermore, the correlation between the number of occurrences and the type of slope materials at the location of the ground motion was carried out using information value method. Based on geological mapping, 5 types of lithology were obtained, namely: alluvium, breccia, sandstone, siltstone, and claystone. Out of 10 landslides that were found, 6 of them occurred in claystone lithology. We interpret that landslide occurrences in study area are relating to the lithology claystone with information value 0.416. The claystone, a part of the Kerek Formation, physically were easily degraded. In addition, this lithology mostly found in open slopes, where the process of erosion by water is more intense.
Numerical Modelling of Wave Attenuation in Pile Breakwater
Authors: Abdullah F.A.R. , Suprijo T. , Diastomo H. , Napitupulu G.
Published: July 2022

Pile breakwater is an artificial coastal structure consisting of closely spaced piles. Its benefits are similar to other coastal structures by attenuating the energy of the incoming wave. In this paper, the wave attenuation caused by the pile structure is investigated using a numerical model, namely the SWASH model. The model allows for simulating non-hydrostatic phenomena in coastal waters as driven by waves. The model setup is conducted in a rectangular wave flume with paddles to produce monochromatic waves on the left and the wave absorber on the other side. Several scenarios were carried out to determine the effect of variations in wave parameters. To deal with the efficiency of numerically modelled pile breakwater, we also investigate the transmission coefficient. We compare the result of the numerical model with experimental data, which took place in a wave flume at Balai Penelitian dan Pengembangan Pantai, Buleleng, Bali, Indonesia. The validation results demonstrate the capability of the SWASH Model to approximate the incident and transmitted wave height with good accuracy compared to experimental data.
Australian–Indonesian monsoon rainfall responses to the northern hemisphere climatic changes prior to the Last Glacial Maximum: an early indication
Authors: Ardi R D W , Aswan  , Maryunani K A , Yulianto E , Putra P S , Nugroho S H
Published: July 2022

The evidences of Australian-Indonesian monsoon (AIM) rainfall response to the northern hemisphere climatic changes from both marine and terrestrial proxies are well established for the Last Glacial Maximum (LGM) – Deglaciation time interval but not in the previous time interval. Sediment cores from off south Sumba (ST10) and off north Sumba (Sumba strait) (ST14) were analyzed using X-Ray Fluorescence method to obtain elemental proxies. Elemental ratios which reflect terrigenous input (Ti/Ca and K/Ca) are used to infer the AIM rainfall changes since ~42 ka BP. AIM rainfall changes indicate a clear response to the Heinrich Events prior to the LGM (H2, H3, and H4). H2 and H3 are corroborated with the AIM rainfall increases in off south Sumba (~24 – 26 ka BP and ~30 – 31 ka BP) while the AIM rainfall increase (~39 – 41 ka BP) in the Sumba strait indicates a response to H4. The cooler temperature during the Heinrich Events could enhance the Northern Hemisphere (NH) cold surges which eventually pushed the Austral summer Intertropical Convergence Zone (ITCZ) southward in a similar fashion to the Last Deglaciation period (~18 – 11 ka BP). The southward movement of Austral summer ITCZ should increase the research area’s exposure time to the Tropical Rain Belt (TRB) during the Australian – Indonesian summer monsoon (AISM) which eventually triggers the AIM rainfall increase. The Sumba strait AIM rainfall unresponsiveness to H2 and H3 could be related to the constant exposure time to the TRB which indicates that the southern limit of Austral summer ITCZ during its northernmost shift didn’t reach the latitude of Sumba Strait. Comparison with other proxies from the same site and other rainfall proxies from southern Indonesia and the northern Australia regions is needed to confirm the spatial extend of those responses.
Characteristics of volcanic rocks and associated intrusions based on petrography analysis in Jari-Krondonan Area, Bojonegoro Regency, East Java
Authors: Marin J , Muhammad Y M , Winarno T
Published: July 2022

Pandan volcano is one of the dormant Quaternary volcanoes in East Java characterized by several volcanic centers which extend to the northern part. This study is aimed to identify the volcanic rocks and intrusions of Jari - Krondonan area, Bojonegoro as well as determine their petrology and mineralogical characteristics. Geological observation was conducted to obtain primary data and to collect samples. Thin section of samples was prepared to analyze the petrographic aspects. Field observation shows several volcanic hills at Mount Jati, Mount Puru, Mount Watu, and Mount Lawang sites. Based on field mapping, lithologies of the research area are andesitic lava and intrusion with columnar joint or sheeting joint structure, surrounded by andesitic breccia. Andesite characterized by porphyritic texture with visible phenocrysts and volcanic glass groundmass. Samples from Mount Lawang and Mount Watu are composed of plagioclase and hornblende as main minerals. Samples from Mount Jati and Mount Puru are composed of plagioclase and pyroxene. Quartz, sanidine, and olivine present as accessory minerals. Plagioclase and pyroxene occasionally formed glomerocryst and poikilitic texture, which play an important role in the fractionation and crystal settling processes. Sieve and regular zoning in plagioclase suggest magma mixing. Gabbro and metamorphic xenoliths found in Mount Lawang and Mount Watu indicates an interaction with country rock during magma rising.
Balancing nature and landscape conservation practices of Leukon Community in Simeulue Island
Authors: Lubis T , Abus A F , Ramlan  , Nasution T , Saputra N
Published: July 2022

This study described the Leukon Community's daily interactions with the natural environment to preserve nature's balance and landscape conservation in social spaces conducive to sustainable growth. The natural environment's behavior features can be studied through the interaction of interacting areas such as fields, flora, and the sea that are habitable for the Leukon Community. Natural resources and the environment play a critical role in the Leukon Community's survival system due to the community's availability and ability to utilize raw materials. This research applies a qualitative strategy, an investigative procedure used to comprehend social or human problems based on a holistic description. The ethnographic technique is employed as a paradigm, with in-depth interviews and participant observation. The results indicate that the Leukon Community practices environmental stewardship by avoiding mechanization and chemical use in farming, capturing fish with environmental friendly technology, and relying on woody tree vegetation for basic requirements. As a result, the delicate balance between nature and environmental preservation is preserved. Avoiding soil and water damage promotes landscape conservation, resulting in a more natural and beautiful landscape. This is because the Leukon Community manages the area sustainably by utilizing natural resources in accordance with local wisdom values and belief systems.