bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance analysis of constant current heated antagonistic shape memory alloy actuator using a differential resistance measurement technique
Authors: Bhargaw Hari N , Botre B A , Singh Samarth , Hashmi S A R , Akbar S A , Sinha Poonam
Published: October 2021

This work presents the development of a precise, constant current heating mechanism for an antagonistic shape memory alloy (SMA) actuator. The actuator was developed using a pair of SMA wires arranged in an antagonistic configuration. SMA possesses a unique phase-dependent, resistance variation property which is called self-sensing. This phenomenon is observed during thermal phase transition. A constant heating current was employed to measure combined differential resistance (ΔR) which provides insignificant hysteresis and linear relationship with displacement. ΔR eventually helps to determine the present position of the actuator for sensorless feedback control. The aim is to remove additional external sensors, reducing actuator footprint and interface complexity using the proposed study. The performance analysis of the actuator was evaluated under constant current by the tracking trajectory of reference signals. The tracking results confirmed the improvement in operating bandwidth by a reduction in displacement. The heating module mainly consisted of a low pass filter, operational amplifier with a current sense feedback mechanism that regulates the heating current in proportion to PWM signals. The result shows a significant 21% variation in the observed value of ΔR (1.200–0.254 Ω) between the major–minor loops. The study confirms linearity and maintains similarity by highest correlation 0.9508 during open-loop, which further improves to 0.9891 in close feedback reference tracking with an error band ±0.05 mm.
Augmented Reality Geometrical Optics (AR-GiOs) for Physics Learning in High Schools
Authors: Kencana H P , Iswanto B H , Wibowo F C
Published: October 2021

This study aims to produce “Augmented Reality Geometrical Optics (AR-GiOs)” as a medium for physics learning for geometrical optics in high school. The method used in this study is the Research and Development method with the ADDIE model (Analyze, Design, Develop, Implement, and Evaluate). AR-GiOs was developed to facilitate students in learning the concept of image formation and image properties of mirrors and lenses. AR-GiOs can display four 3D simulations, including 3D simulations of the image formation process by a concave mirror, a convex mirror, a concave lens, and a convex lens. In addition to AR, in this study, a worksheet was also developed to guide student learning activities and valuable as a marker. The results of product validation covering the material and media aspects got a very good average score (84% and 90%). Based on the results of the expert validation test, it can be concluded that AR-GiOs is suitable for use as a medium for learning physics in high school.
Design of Massive Online Simulation in The Learning Physics of Thermodynamics Process
Authors: Lestari M A , Wibowo F C , Delina M
Published: October 2021

The thermodynamic process is an important material in learning physics. The needs analysis stated that 96.8% of students still experienced difficulties in understanding the thermodynamic process material. One of the media that can be used to help students understand the phenomenon of thermodynamic processes is simulation. This study aims to design a physics learning media in the form of a Massive Online Simulation (MOS) that can be accessed via an internet connection. The development model used in this study is ADDIE (analysis, design, develop, implement, evaluate), but in this study it was only carried out until the design stage. Analysis stage is obtained through literature study and student and teacher needs analysis. At the design stage, it focuses on making Massive Online Simulation (MOS) media designs on thermodynamic processes. This research is expected to produce a physics learning media design in the form of a Massive Online Simulation (MOS) on thermodynamic processes which can be an alternative to online-based interactive learning media that can be accessed anywhere and anytime.
Development of Online Learning Videos: An Innovation for Higher Education Students in Electromagnetic Experiment Course During a Pandemic COVID 19
Authors: Yogihati C I , Putri D S , Suaidi D A , Hartatiek  , Yudyanto
Published: October 2021

The ongoing COVID-19 pandemic has led to government decisions regarding the continuation of online lectures. This transformation becomes a problem in the ongoing compulsory course for students, namely electromagnetic experiment. Until finally the researchers chose video media as the answer to these problems. In the process, video development was carried out in two cycles. Through this development, the researcher wanted to know the ability of video in presenting data and its feasibility. The subjects of this study were students of S1 Physics Education, Universitas Negeri Malang in batch 2019 with a total of 100 people. This video was developed using the Four-D method which consists of defining, designing, and developing stages. The first cycle video acts as the preceding video and the second cycle video acts as the development result video. Practical reports and student assessment questionnaires are used as a review of development results. As a result, students obtained an average experiment report score of 93 in the first cycle and 96 in the second cycle. Student assessments related to the first cycle of media showed that 70.57% stated that they were feasible and became 79.86% in the second cycle.
Implementation Management Strategies for Modern Physics Experiment with Online Systems Approach to Improve The Quality of Learning or Physics Students
Authors: Sutrisno  , Simaremare A , Suyudi A , Taqwa M R A , Parno
Published: October 2021

Since COVID-19 broke out in early 2020, State University of Malang has implemented online lectures. This transformation creates new problems, including in Modern Physics experiment lectures. The fact is that when students was founded with the problem of assembling complex tools they are unable to implement their knowledge. The problems with Modern Physics experiment lectures that have existed for a long time are now exacerbated by the emergence of the COVID-19 pandemic. In overcoming this problem, the researcher implementation, management strategy with a systems approach as a solution with the consideration that this strategy is able to direct students to think critically. This study aims to improve students’ practical understanding and learning quality. This research was conducted in 2 cycles. The research instruments were questionnaires and experiment reports. Based on the data analysis of the questionnaire cycles I and II, it was concluded that the quality of the implementation of modern physics experiment learning was good with an average result of 88.38%. In addition, there is an increase in students’ practical understanding which can be seen from the average score of the experiment report, where the first cycle is 91.33 and the second cycle reaches 95.
The Influence of Discovery Learning Model using PhET and Scientific Skills of Class XI High School Students
Authors: Ramadhan L A , Budi A S , Delina M
Published: October 2021

This study aims to determine the effect of interaction between discovery learning models and scientific attitudes on students metacognitive skills. The method used in this study is a quasi experimental design of treatment by level 2x2. The number of samples in this study was 144 high school grade XI students. The sample was divided into two, namely the control class and the experimental class. The control class was given learning using the free discovery model while the experimental class uses the guided discovery model by having high and low student scientific attitudes. After treatment was given to both groups, a test was conducted to find out the students metacognitive skills. Then compare the two results to see the interaction between learning models and scientific attitudes towards students metacognitive skills.
Digital Storytelling of Physics (DiS-Phy): Learning Physics from Home Through Stories
Authors: Sanjaya L A , Putri E A , Wibowo F C , Robby D K , Puspa R W D , Pertiwi W A , Sianipar L K , Qoiriyah W , Sitompul H
Published: October 2021

This study aims to develop a product such as “Digital storytelling of Physics (DiS-Phy)” that can be used as a physics’ educational media for distance learning (PJJ) on magnetic field material. DiS-Phy developed as a digital storytelling media which is able to combine several learning media such as writing, pictures and learning videos in one medium. The developed DiS-Phy also equipped with scientific literacy questions. DiS-Phy can be accessed on all types of distance learning devices such as smartphones, laptops and tablets that are connected to the internet. DiS-Phy including the type of research and development (Research & Development) which refers to the ASSURE model. The result of validation test shows the percentages of 91,07%, according to subject-matter expert, 93,16%, according to media expert and 87,50% according to learning expert. DiS-Phy also tested by 4 physics teachers at senior high school in Jakarta that achieved 92,57% points that make this product has been qualified as a worthy physics’ distance learning device. Also of 35 as respondents in this study shows the percentages of 87,48% points that make this product worthy to use as an educational media. Based on the results, it can be concluded that the DiS-Phy has been qualified as a worthy physics’ distance learning device for teachers and students.
TPACK and Augmented Reality in Kinematics Practicum Module: Forming HOTS Physics Education Students
Authors: Bakri F , Kusuma R , Permana AH
Published: October 2021

High Order Thinking Skills (HOTS) are needed to support 21st-century skills. Students are required to think critically in overcoming a problem. HOTS can be trained through the lab activities. The method used in this research is research and development (R&D) with a Dick & Carey approach. This article described the implementation of TPACK and augmented reality in the kinematics practicum module to forming HOTS for physics education students. This practicum module has implemented integrated technology, pedagogy, content, and knowledge. The addition of augmented reality media makes it easier for students to understand practicum steps and forms of phenomena related to practicum. The module was declared feasible in terms of material, media, and pedagogical concepts in forming the HOTS abilities of physics education students. The stages of HOTS formation in the module present a video of real-world phenomena as a stimulus, and students are asked to answer the pre-test related to the stimulus video, students are asked to create observation tables according to the steps in the practicum, students are asked to process data, and analyze concepts regarding practical material which is related.
TPACK in Blended Learning Media: Practice 4C Skills for Rotational Dynamics in Senior High School
Authors: Susila A B , Indiyahni I , Bakri F
Published: October 2021

In the 21st century, the fields of ICT and education are like two sides of a coin that cannot be separated. The skills of students must support the rapid development of science and technology. Workers in the 21st century have at least 4C competencies, namely: critical thinking, communication, collaboration, and creativity. The emergence of the Covid-19 in 2020 demands a blended learning model as an ideal learning process. This article describes research on website development as a blended learning medium for rotational dynamics in high school. The research method used is Research and Development with a Dick & Carey approach. Media has been produced in a website that combines technological knowledge, pedagogical knowledge, and physics content knowledge (TPACK) in multiple representations with stages to train students’ 4C skills. The stages of 4C skills on the website as a blended learning medium that developed were: (1) criticizing initial information; (2) developing and compiling arguments, reasons, assumptions, and evidence; (3) communicating arguments, reasons, assumptions, and evidence; (4) criticizing the quality of arguments, reasons, assumptions, and evidence; (5) open-minded; (6) seek new information; (7) conclude. Media also facilitates communication between users to build networks and improve collaboration capabilities. The results of this study have been tested for eligibility by material physicists, learning experts, and media experts. The eligibility test results of the website as a blended learning medium for rotational dynamic material in high school were declared eligible to practice 4C skills.
Blackbody Radiation Experimental Apparatus (Arabeta) to Support Physics Learning for Senior High School Students
Authors: Safari I , Susilo A B , Rustana C E
Published: October 2021

As part of ongoing research to develop a tool for teaching thermal radiation, we have constructed an Experimental Apparatus of Blackbody Radiation (ARABETA). Some previous researches have been conducted to investigate students understanding of Modern Physics, but very little on the topic of Black-body radiation. Apart from being more abstract, the experimental apparatus on this topic are also almost difficult to find in school laboratories. A preliminary study that involved 53 physics teachers in Jakarta region confirmed that black body radiation is a concept that is difficult to visualize to students during learning. Therefore, we developed a simple apparatus that is capable of measuring the temperature and thermal radiation of the samples used. This research uses research and development model by following some steps of Borg and Gall. The results of this measurement are shown in a graph of intensity against the multiplication result of the Stefan-Boltzmann and the fourth power of its absolute temperature, so that the emissivity value of the sample can be obtained. Through this development, we may provide an alternative solution for the experimentation issue in the learning of blackbody radiation at senior high level.
Transition of Learning Physics Technology Using Virtual Practicum to High School Physics Teachers in Aceh Barat District
Authors: Farhan A , Wahyuni A , Herliana F , Akhyar A
Published: October 2021

Practicum is one of the essential learning aspects of physics learning that is required in the 2013 curriculum. The problem of High School Physics teachers in West Aceh Regency is the limited facilities and infrastructure for the Physics laboratory. The development of Information Technology (IT) enables the Virtual Laboratory of Physics is implemented using a smartphone device. Technology transfer using IT in learning is carried out for High School Physics teachers in the West Aceh district. The method used is physics training using virtual experiments. The training participants are all High School Physics teachers in West Aceh District. The aim of the activity is to train physics teachers’ ability of IT which can be applied in learning activities at High Schools in the West Aceh district. The results of the activity were that 100% of the participants could master IT technology using a Smart Phone for a virtual practicum on Wave material. Therefore, they feel that there is an increase in their pedagogical ability in carrying out their duties and the optimists can apply this in the learning process in their place of duty. 75% of trainee teachers believe that the application of virtual practicum methods in learning can improve students’ understanding of physics subject matter; 12.5% of participants were not sure and 6.25% of participants were not sure that learning Physics using the virtual experiment method could improve students’ understanding. The benefits of the activity are expected to increase the human resources of High School Physics teachers in West Aceh district in utilizing the Virtual Laboratory so that it supports the physics learning process using practicum methods and online learning.
Analysis of Phase Change of BaTiO3 Ferroelectric Material from a Tetragonal Crystal Structure (BaTiO3) to Orthorhombic (Ba4Ti13O30) to Monoclinic (Ba6Ti17O40)
Authors: Irzaman
Published: October 2021

BaTiO3 ferroelectric material is very interesting to study, because BaTiO3 ferroelectric material has spontaneous polarization properties when given an electric field from outside the system. This spontaneous polarization property of BaTiO3 ferroelectric material can be applied as a light sensor (ferroelectric properties), temperature sensors (pyroelectric properties), pressure sensors (piezoelectric properties). Has successfully analyzed the phase change of BaTiO3 ferroelectric material from a tetragonal crystal structure (BaTiO3) to orthorhombic (Ba4Ti13O30) to monoclinic (Ba6Ti17O40) using the Cramer-Cohen method. This shows that the Cramer-Cohen method is very accurate in calculating the lattice constants of the crystal structure of ferroelectric materials and other materials.
Synthesis of Silicon Dioxide (SiO2) from Reeds Biomass (Imperata cylindrica) and The Analysis of Electrical Properties (Study Cases: Impedance, Resistance, Capacitive Reactance, Inductive Reactance)
Authors: Wardani D A P , Hariyanto B , Kurniawati N , Har N P , Darmawan N , Irzaman
Published: October 2021

Silicon dioxide (SiO2) has successfully synthesized from reeds biomass (imperata cylindrical) by annealing temperature variation at 500, 600, 700 oC. The result of the synthesis has analyzed using LCR meters to calculate the electrical properties including resistance (R), reactance (X) (delta inductive reactance (XL) and capacitive reactance (XC)), impedance (Z) in the frequency range at 50 Hz to 5 MHz. The resistance (R), reactance (X) (delta inductive reactance (XL) and capacitive reactance (XC)), impedance (Z) value according to reversible electric current rules.
Effect of Milling Time on The Desorption Temperature of Mgh2-10wt% Fe3O4 for Hydrogen Storage Materials Application
Authors: Ulandari A , Rahwanto A , Handoko E , Jalil Z
Published: October 2021

The effect of milling time on the desorption temperature of hydrogen storage material MgH2-Fe3O4 has been carried out. This study aims to determine the effect of milling time variation and the effect of adding Fe3O4 catalyst on the characterization of MgH2. Milling time variation using mechanical alloying technique, with milling time given for 10 hours, 20 hours, 30 hours with a ball ratio of 10: 1 and a speed of 350 rpm. MgH2–10wt% Fe3O4 was characterized using XRD and DSC. The results showed the phases of MgH2, MgO, and Fe3O4. The crystal grain size of MgH2 decreased from 11.81 nm to 8.35 nm. Variation of ownership time and the addition of Fe3O4 catalyst can reduce the desorption time from 377oC to 369oC.
Python-based Program for Analysing Lattice Parameter of Cubic and Tetragonal Crystal Structure
Authors: Rizky A , Fadhillah A , Irzaman  , Irmansyah
Published: October 2021

A program for analysing lattice parameter of a crystal structure has been successfully created based on Python programming language using the Google Collaboratory service, so it can be accessed through a PC or smartphone as long as internet access is available. This program can be used to calculate lattice parameter of a crystal structure with x-ray diffraction data as the input. Crystal structures that can be calculated for its lattice parameter are cubic and tetragonal. The program will ask for the type of crystal structure of the data, along with diffraction angles and miller indices. The input will be processed using the Cramer-Cohen method according to the previously entered crystal structure. By also entering the wavelength used, the output of this program is the lattice parameter in the angstrom unit. The percentage of error of this program’s output is extremely low.
Identification of Seawater Intrusion in Kota Lama Semarang and Surrounding Based on Geoelectrical Resistivity Survey
Authors: Supriyadi  , Fitrianto T N , Khumaedi  , Sugiyanto
Published: October 2021

Kota Lama Semarang is a tourism potential that causes a high demand for groundwater, which can cause seawater intrusion. Seawater intrusion can affect groundwater quality and soil conditions. This research aimed to determine the depth and distribution of seawater intrusion in the Kota Lama Semarang and surrounding. The research used electrical resistivity tomography (ERT) and vertical electrical sounding (VES). Geoelectrical resistivity surveyed consist of 4 ERT lines and 3 VES lines with a line length was 100 to 160 m. Lines were scattered north and south of the Kota Lama to determine the distribution of seawater intrusion. Inversion processing used Progress for VES and Res2DInv for ERT. The content of chloride as well in Kota Lama was measured as supporting data. At this location it was estimated that it has 3 layers: top soil, sand and sandy clay. The sand layer at a depth of 3 to 11 m was the layer affected by seawater intrusion. Seawater intrusion on the north side was higher than on the south side. This was indicated by the lower resistivity value of the groundwater layer on the north side. The resistivity value of the groundwater layer on the north side was 0.96 Ωm while the south side was 3.76 Ωm. This result was appropriate to the chloride content which indicates a higher concentration on the north side of the Kota Lama Semarang.
Design, Prototype of Arduino and Android-Based Anthropometry System for Toddler’s Head and Upper Arm Circumference Measurement
Authors: Umiatin  , Mauldy R M , Indrasari W
Published: October 2021

Nutritional status monitoring is a very important in toddler, because in this period children are vulnerable to trauma, infection, or developmental disorders. Nutritional status is one of the health indicators in the successful achievement of MDGs No. 4 related to the reduction of child mortality, which is 45% caused by malnutrition. Head and upper arm circumference are an important anthropometry parameter on toddler growth. The monitoring process for toddler in Posyandu usually by writing and plotting the data in KMS (Kartu Menuju Sehat) manually. Therefore, efforts to modernize Posyandu to facilitate Posyandu officers in taking measurements, as well as become one of the database systems of nutritional status of Indonesian toddler. The purpose of this study was to develop prototype of anthropmometry using ultrasonic sensor HC-SR04 and Hall sensor UGN3503 based Arduino. The system will be integrated with the database through Android applications. The results of this study had an accuracy value of 97.72% for the testing of head circumference measuring instruments and 95.35% of the testing of upper arm circumference measuring instruments. Android applications created to serve to store and provide information about the growth and development and nutritional status of a toddler
DC-DC Buck Converter Circuit Simulation on Solar Panel Electricity Storage System
Authors: Indrasari W , Prasetya F A I , Setiadi R N
Published: October 2021

Electrical energy is one of the energies that humans widely use. One of the components used to generate electrical energy is solar cells. By using solar cells, energy can be stored in a battery or used directly. In stores electrical energy into the battery using DC-DC converter is still found to have a loss of power that affects the low efficiency of electricity generated. So it needs a system that can control the process of storing energy to the battery, one of which uses a DC-DC converter with Buck topology that will be used on solar panel electrical power storage system. To optimize the DC-DC Buck converter circuit, we plan a circuit simulation by considering the value of the quality factor Q of the Butterworth filter. The test results showed that the filter with a value of Q = 0.707 was of good quality with a gain of -3.1 dB. If the Q value increase, the gain will be increased, and the time it takes until the voltage stabilizes increases.
Study Surface Area and Pore Size Distribution on Synthetic Zeolite X using BET, BJH and DFT Methods
Authors: Allanas E , Rahman A , Arlin E , Prasetyanto E A
Published: October 2021

The characterization of zeolite X synthesized from Bintan bauxite using nitrogen physisorption technique that employs the BET, BJH and DFT equations was proposed to improve the understanding of the pore characteristics of zeolite X. The BET, BJH and DFT methods were chosen because the characteristics of the synthesized zeolite were characterized using a scanning electron microscope (SEM) showed a typical morphology for zeolite X and zeolite A crystals and the presence of amorphous phase in small abundance. Evaluation is needed to understand the characteristics of micropore, mesoporous and macropore of zeolite X as a synthesis and the best methods. The data obtained show that the DFT method is the most appropriate and superior model to describe the pore size distribution of synthesized zeolite X.
Watt Peak Meter of Solar Panel
Authors: Manfaluthy M , Pangestu A , Arif R , Sanjaya L A
Published: October 2021

The design of a watt peak meter of solar panel has been carried out using an LDR sensor to obtain the strongest light as the sun moves. The electronic circuit used includes LDR KY018, WEMOS ESP32, servo motor, Solar Charger Controller, INA219 Power Sensor, Battery and 10 A / 5V Relay. The mechanical structure uses angle iron construction which is assembled in such a way as to support solar panels with the SUNLITE Model 156P-20 type. Solar panels are positioned on 2 poles and attach the bolts as the rotary axis. LDR that gets sunlight will provide input to the WEMOS ESP32 to drive the servo motor in line with the direction of the sun in the east - west direction. The result led to an average 93,7% close to number as stated in the data specification of solar panel.
Effect of Pulse Electromagnetic Field Exposure on the Expression of Lipo Protein Lipase (LPL) on the Differentiation of Mesenchymal Stem Cell
Authors: Umiatin  , Indrasari W , Taryudi  , Sari P , Mazfufah N F , Rosadi I
Published: October 2021

Pulsed electromagnetic fields (PEMFs) have an important role in cell differentiation. Previous study reported that PEMFs had positive and negative effect towards cell differentiation that depends on their frequencies applied to the cells. Human adipose-derived stem cells (ASCs) are mesenchymal stem cells that have an ability to differentiate into several types of cell including adipocytes, chondrocytes and osteocytes. This study aimed to evaluate the effect of human ASCs towards their adipogenic differentiation during PEMFs exposure. Human ASCs were isolated from adipose tissue. The cells then cultured in specific medium of adipocyte that induced ASCs differentiation along with PEMFs exposure. The maximum magnetic field used is 2 mT with a frequency of 75 Hz. To confirm the effect of PEMFs exposure towards adipogenic differentiation, mRNA expression of lipo protein lipase (LPL) was measured in mRNA expression level. The results showed that ASCs cultured on adipogenic differentiation without PEMFs exposure gradually increased LPL expression until day 14 of observation, while ASCs with PEMFs exposure significantly decreased LPL expression from day 2 to day 14. Based on the results, we concluded that PEMFs exposure can inhibit LPL expression that suppressed adipogenic differentiation.
PT

symmetry, pattern formation, and finite-density QCD
Authors: Schindler Moses A. , Schindler Stella T. , Ogilvie Michael C.
Published: October 2021

A longstanding issue in the study of quantum chromodynamics (QCD) is its behavior at nonzero baryon density, which has implications for many areas of physics. The path integral has a complex integrand when the quark chemical potential is nonzero and therefore has a sign problem, but it also has a generalized

PT

symmetry. We review some new approaches to

PT

-symmetric field theories, including both analytical techniques and methods for lattice simulation. We show that

PT

-symmetric field theories with more than one field generally have a much richer phase structure than their Hermitian counterparts, including stable phases with patterning behavior. The case of a

PT

-symmetric extension of a φ4 model is explained in detail. The relevance of these results to finite density QCD is explained, and we show that a simple model of finite density QCD exhibits a patterned phase in its critical region.
The use of virtual reality and fuzzy neural network tools to identify the focus on achieving project results
Authors: Velikanova A S , Polshchykov K A , Likhosherstov R V , Polshchykova A K
Published: October 2021

In the process of making a decision on the inclusion of an applicant in the project team, it is proposed to take into account his project results targeting (PRT). The article describes the conceptual basis for identifying people’s focus on achieving the results of significant projects based on the use of virtual reality tools and the capabilities of fuzzy inference systems. At the same time, to configure the parameters of the membership functions of the fuzzy inference system and the values of the individual inferences of the fuzzy rules, the use of a neural-fuzzy network is proposed. To get a training sample, the participants of the teams of implemented projects will need to pass a series of tests using virtual reality tools. According to the proposed concept, persons with high PRT will be primarily recommended for inclusion in the team of project performers.
Planning maize hybrids adaptation to future climate change by integrating crop modelling with machine learning
Authors: Zhang Liangliang , Zhang Zhao , Tao Fulu , Luo Yuchuan , Cao Juan , Li Ziyue , Xie Ruizhi , Li Shaokun
Published: October 2021

Crop hybrid improvement is an efficient and environmental-friendly option to adapt to climate change and increase grain production. However, the adaptability of existing hybrids to a changing climate has not been systematically investigated. Therefore, little is known about the appropriate timing of hybrid adaptation. Here, using a novel hybrid model which coupled CERES-Maize with machine learning, we critically investigated the impacts of climate change on maize productivity with an ensemble of hybrid-specific estimations in China. We determined when and where current hybrids would become unviable and hybrid adaptation need be implemented, as well as which hybrid traits would be desirable. Climate change would have mostly negative impacts on maize productivity, and the magnitudes of yield reductions would highly depend on the growth cycle of the hybrids. Hybrid replacement could partially, but not completely, offset the yield loss caused by projected climate change. Without adaptation, approximately 53% of the cultivation areas would require hybrid renewal before 2050 under the RCP 4.5 and RCP 8.5 emission scenarios. The medium-maturing hybrids with a long grain-filling duration and a high light use efficiency would be promising, although the ideotypic traits could be different for a specific environment. The findings highlight the necessity and urgency of breeding climate resilient hybrids, providing policy-makers and crop breeders with the early signals of when, where and what hybrids will be required, which stimulate proactive investment to facilitate breeding. The proposed crop modelling approach is scalable, largely data-driven and can be used to tackle the longstanding problem of predicting hybrids’ future performance to accelerate development of new crop hybrids.
Topological aspects of theta-curves in cubic lattice*
Authors: No Sungjong , Oh Seungsang , Yoo Hyungkee
Published: October 2021

Knots and embedded graphs are useful models for simulating polymer chains. In particular, a theta curve motif is present in a circular protein with internal bridges. A theta-curve is a graph embedded in three-dimensional space which consists of three edges with shared endpoints at two vertices. If we cannot continuously transform a theta-curve into a plane without intersecting its strand during the deformation, then it is said to be nontrivial. A Brunnian theta-curve is a nontrivial theta-curve that becomes a trivial knot if any one edge is removed. In this paper we obtain qualitative results of these theta-curves, using the lattice stick number which is the minimal number of sticks glued end-to-end that are necessary to construct the theta-curve type in the cubic lattice. We present lower bounds of the lattice stick number for nontrivial theta-curves by 14, and Brunnian theta-curves by 15.
Reviewing the characteristics of slip behaviour for megathrust earthquake at Sumatera using vertical derivative of GOCE satellite gravity field
Authors: Aristo  , Iskandarsyah
Published: October 2021

The review of the seismogenic zone characteristics associated with the earthquake rupture process in the Sumatra Subduction Zone has been carried out by various methods. This zone has experienced several major earthquakes; Aceh 2004 Mw=9,1, Nias-Simeulue 2005 Mw=8,6, Bengkulu 2007 Mw=8,5, and Enggano 2000 Mw=7,9. This study focuses on the relationship between density contrast analysis based on gravity data from the GOCE satellite and the slip distribution in four major earthquake rupture zones. Satellite gravity data processing is carried out to obtain data for Gravity disturbance (Gd) and vertical gravity derivatives (Tzz), corrected by topography and sediment effects with different spectrum decomposition to get gravity maps with different depths. Based on the Tzz analysis, the maximum slip of the earthquake rupture is correlated with the minimum Tzz pattern and low-density contrast. In contrast, the rupture ends at the maximum Tzz pattern and high-density contrast. Tzz pattern and Gravity disturbance can describe the barrier and asperity of the Sumatra subduction zone. The schematic maps portray the seismic segmentation of Sumatra Subduction, which have asperities zone along the subduction strike associated with the minimum Tzz and associated with the forearc zone, as well as the barrier related to the maximum Tzz, which is a manifestation of structures (fracture zone and seamount) that are subducted to the oceanic plate.
Analysis of the effect of magnetotelluric data quality improvement using rho variance and edit XPR parameters in densely populated areas
Authors: Widodo A , Lestari W , Warnana D D , Syaifuddin F , Rivensky R S , Ilmawan R Z
Published: October 2021

Magnetotelluric (MT) research was conducted to map the fault structure in the western part of East Java. The advantage of the magnetotelluric method is its deep penetration because it propagates at a low frequency so that it can detect resistivity anomalies that are thought to be faults. The measuring path of the magnetotelluric method covered the Surabaya and Gresik areas. Research conducted in densely populated areas thus it requires a noise reduction process to improve the quality of the data. Performing the robust processing with Rho Variance parameters and editing XPR is an effort to reduce noise and to improve the quality of magnetotelluric data. The robust processing result of 5 (five) sounding MT data using the Rho Variance parameter can improve the quality of magnetotelluric data by increasing the coherence value of 2.128% (MT01), 2.804% (MT02), 2.378% (MT03), 3.508% (MT04), and 3.129% (MT12). Meanwhile, the editing XPR process can increase the coherence value of 0.184% (MT01), 7.155% (MT02), 9,364% (MT03), 0.784% (MT04), and 0.628% (MT12). Escalation of coherence value by implemented the Rho Variance and Editing XPR means that two methods are sufficient effectively to raise the confidence level of MT data processing and interpretation result.
Comparison of three recurrent neural networks for rainfall-runoff modelling at a snow-dominated watershed
Authors: Yokoo K , Ishida K , Nagasato T , Ercan A , Tu T
Published: October 2021

In recent years, rainfall-runoff modelling using LSTM has shown high adaptability. However, LSTM requires far more computational costs than traditional RNN. In addition, a different type of RNN, GRU, has been developed to solve this issue of LSTM. Therefore, this study compares the accuracy of the deep learning methods for rainfall-runoff modelling using three deep learning methods in a snow-dominated area. Besides, the setting of hyperparameters may affect accuracy. The accuracy of these deep learning methods was investigated by trying multiple combinations of hyperparameters. The input data were daily temperature data and precipitation data. The results show that GRU gives the highest accuracy in most combinations.
3D stratigraphic modelling of the Bangkok basin using Kriging on borehole data
Authors: Subedi B , Kitaoka T , Kiyono J
Published: October 2021

The Lower Central Plain of Thailand has a deep and highly irregular basement filled with complex layers of alluvial sandy soil and deltaic clay or silt. The Bangkok Metropolitan region with its high level of infrastructure development is located in this plain. With high population density, the problem of land subsidence is critical. This study uses borehole data and the Kriging method to interpolate the data. A detailed 3D stratigraphic model of the basin is presented and several cross sections along two directions. Seventeen layers and the points used for modelling each layer are presented. The model shows eight aquifers in the Bangkok basin, lying between eight layers of clay, and a bottom layer above the basement. The bottom of the lowest aquifer of the Bangkok aquifer system is 610 m deep. The basement extends down to a depth of more than 2000 m in some places. Our 3D model, which extends to the basement, is of interest for mining and site-specific seismic risk analysis. Moreover, our results can be very useful for groundwater and land subsidence studies.
Deformation identification using DInSAR multi temporal analysis method in supporting infrastructure development (case study of the area around the nation’s new capital)
Authors: Puspita A , Prihanto Y , Martha S , Martha A A , Gultom A G
Published: October 2021

The relocation of nation’s capital is one of the government’s flagship programs at this time. The lack of information on soil structures that are prone to deformation can bring an impact on the failure of infrastructure development in the areas of New State Capital (known as Ibu Kota Negara/IKN). Therefore, a significant study is important to find out the deformations that may occur in the region as an initial information in determining the location for safer infrastructure development based on the soil structure conditions in the research area. This research used the Differential Interferometry Synthetic Aperture Radar (DInSAR) method with a multi-temporal approach to identify the deformations in the research area. The data included SAR images of Sentinel 1A type SLC with C band (5.405 GHz) for the period 2015-2019. The results confirmed that deformation had been identified in several areas, both those experiencing subsidence and uplifting. The maximum subsidence was 12.97 cm at Sepaku district on period 2018-2019 and the maximum uplift was 10.01 cm on period 2017-2018. The identified areas with deformation generally take place in areas with a high density of buildings, construction areas, road infrastructure, and river alluvial deposits.
Analysis of the distribution of seawater intrusion using electrical conductivity and total dissolved solid data and intelligence for residents in Sayung District, Demak Regency
Authors: Ariwibowo K L , Riski A M , Fajarulloh A S , Putranto T T
Published: October 2021

Massive groundwater extraction from production wells can trigger seawater intrusion, such as what happened in Sayung District, Demak. Seawater intrusion can be identified using quality analysis in the form of the electrical conductivity of each water sample taken. The research area is located in Sayung District, Demak Regency and is on the north coast, and is composed of alluvium quaternary deposits in the form of clay, sand sediments, and organic material of the plant. The purpose of this study is to determine the distribution of seawater intrusion in Sayung District and to know the prediction of the direction of seawater intrusion to provide an overview of groundwater quality recommendations in the study area to residents. To determine the distribution of seawater intrusion, you can use Electrical Conductivity and TDS (Total Dissolved Solids) data, from the results of the analysis there is a decrease in groundwater quality as indicated by the electrical conductivity value in the range 2,800-3,265 μmnos/cm with slightly brackish salinity and damage levels. categorized as critical and has a relatively high TDS value in the range 1,904-2,220.2 mg/L which is spread in the northern part near the coast including Timbulsloko and Sidorejo villages.
Soil stiffness identification using fuzzy logic based on seismic tomography and its relationship with dynamic elastic moduli
Authors: Yufajjiru L , Maryadi M
Published: October 2021

Either P-wave or S-wave tomography has been used to interpret soil stiffness zone to extend subsurface conditions’ visibility. The dynamic elasticity moduli have been calculated to connect both seismic wave velocities to geotechnical rationale. However, the interpretation has to be more integrated and less subjective. Fuzzy logic has been applied for both velocities fusion to generate geotechnical cross-sections to diminish the subjectivity. Nevertheless, this is a new application, and it is not known whether this result has a relation to the dynamic elasticity moduli or not. Therefore, this research uses Fuzzy Logic to identify the soil stiffness zone and its relationship to the dynamic elasticity moduli. Meta-hypotheses are produced by possibility function in the early phase of the fusion. The possibility function is a fuzzy set that describes each seismic wave velocities to a geotechnical rationale in a possibility scale. Meta-hypotheses fused into hypotheses: the possibility of solid-state behavior and plastic-state behavior. It is found that solid-state behavior is analog to Bulk modulus, and the plastic state is analog to the elastic modulus. Both hypotheses’ extreme values are highlighting the target based on the geotechnical rationale from the possibility function.
Petrography and geochemistry preliminary study of Pucangan Serpentinite Geosite Karangsambung – Karangbolong Geopark Central Java, Indonesia
Authors: Isyqi  , Ansori C
Published: October 2021

Geosite is a Geological Heritage object in the Geopark area with specific characteristics and is an integral part of the evolutionary history of forming an area. Serpentinite Pucangan is one of the Geosite located in Karangsambung – Karangbolong geopark. This study aims to find out the characteristics of petrography and geochemistry of Serpentinite Pucangan Geosite. The methods used in this study include literature studies, fieldwork research, petrography analysis, ore microscopy analysis, whole rock analysis consist of major element analysis using fusion inductively coupled plasma (Fus ICP) methods, trace element analysis, and rare earth element analysis using inductively coupled plasma mass spectrometry (ICP-MS) methods. Serpentine minerals with antigorite type dominate the petrography composition of Pucangan serpentinite with a little magnetite mineral. SiO2, MgO, and Fe2O3(t) are the major elements with the largest percentage of 37.93%, 5.78%, and 9.73% that have an agreement with the mineralogical composition of the rock that dominated by ferromagnesian minerals. This Geosite is interpreted to be formed due to the metasomatic process when the subduction process is happening in this area in the Pre-tertiary period.
An integrated approach using microtremor data for field development and reservoir monitoring: an example from Betung Field, Jambi
Authors: Pascarizativa R. , Haris A , Alwi M S A
Published: October 2021

Reservoir monitoring is one of the most important aspects in oil and gas field management, because it provides industries with the required data in hydrocarbon optimization. This is often carried out in Indonesia by the TAC Pertamina-Pusako Betung Muaro Senami Jambi (PBMSJ), an organization responsible for the management and coordination of oil well activities. In 2012, the organization conducted passive seismic data acquisition and series of drilling campaigns, which successfully increased oil production in Betung Block from 43 to 652 bopd. This campaign was successfully carried out through one and two wells in 2013 and 2014, respectively. Furthermore, the pre-2017 interpretation describes the Betung Anticline as a relatively symmetrical and low angle N-S trending field, which defies the South Sumatra Basin Northwest-Southeast regional trend. This anticline, bound by two high angle normal faults, is unable to define the LKO/OWC position, leading to the consideration of a more integral interpretation approach by the PBMSJ team in early 2017. The procedure was conducted through the use of a 2d seismic line bounded with new wells and SRTM imagery, to combine subsurface structural data with the surface fundamental analogue. In 2017, a passive seismic study was repeatedly conducted in the Betung field, with only 30 measuring points. The urgency in identifying the reservoir is essential within the petroleum industry, in order to produce sufficient hydrocarbons. It is also essential in confirming the potential uses of microseismic data in storage decision-making, through a dataset acquired in Betung, based on reservoir management.
Comparative evaluation of the efficiency of enhancing phytoextraction with heavy metals in Phaseolus vulgaris, Pisum sativum, Sinapis alba using a disubstituted potassium salt of oxyethylene diphysphonic acid
Authors: Makarova A S , Chelnokov V , Matasov A , Nikulina E A , Golenko M G , Pishchaeva K V , Romanova R A , Fedoseev A N
Published: October 2021

It is possible to increase the efficiency of phytoextraction by introducing additives that convert less bioavailable compounds of heavy metals into bioavailable fractions in the soil, as well as to increase the rate of transfer of metals into the plant body. The article presents the results of a study of various chemical additives that affect the development and growth of plants when the soil is contaminated with heavy metals (Ni, Cu, Cd). It can be concluded that the disubstituted potassium salt of hydroxyethylidene diphosphonic acid is a growth stimulant for some plant species, and an increase in growth directly depends on an increase in the concentration of the additive introduced. The work was supported by the Russian Foundation for basic research (RFBR) under the project 18-29-25071.
Biological method based on track membranes to form controlled gaseous media for fruit cold storage
Authors: Kostiuk V A , Kolodyaznaya V S , Rumiantceva O N , Kiprushkina E I , Shestopalova I A
Published: October 2021

The article proposes a biological method based on the use of gas-selective track membranes to form a modified gas atmosphere, considering the respiration rate of fruit. The work aims to study the change in the respiration rate of apples depending on the variety and storage time to substantiate the formation of the gas medium composition depending on the respiration rate of the fruit and the area of track membranes, and to study the kinetics of oxidation reactions of biologically active substances during cold storage of apples. The research is based on autumn apple varieties: Grushovka Yudicheva, Kordonovka and Pepin Shafranny. We have obtained the kinetic curves of changes in the content of mono- and disaccharides, ascorbic and organic acids in autumn apple varieties depending on the gas composition in terms of oxygen and carbon dioxide content, as well as the duration of fruit storage using track membranes. For maximum quality preservation, nutritional and biological value of the studied apple varieties at t = (3 ± 1) °C, we have determined a recommended composition of the controlled gas atmosphere: oxygen concentration - (5.2 ± 0.1%), carbon dioxide - (3.6 ± 0.1%). Controlled atmosphere is created using a gas-selective composite membrane with an area of 14-22 cm2/kg, depending on the variety and respiration rate.