bluuebunny/crossref_metadata_2025 huggingface dataset:
Flex-printed forehead EEG sensors (fEEGrid) for long-term EEG acquisition
Authors: Blum Sarah , Emkes Reiner , Minow Falk , Anlauff Jan , Finke Andrea , Debener Stefan
Published: May 2020

Objective. In this report we present the fEEGrid, an electrode array applied to the forehead that allows convenient long-term recordings of electroencephalography (EEG) signals over many hours. Approach. Twenty young, healthy participants wore the fEEGrid and completed traditional EEG paradigms in two sessions on the same day. The sessions were eight hours apart, participants performed the same tasks in an early and a late session. For the late session fEEGrid data were concurrently recorded with traditional cap EEG data. Main results. Our analyses show that typical event-related potentials responses were captured reliably by the fEEGrid. Single-trial analyses revealed that classification was possible above chance level for auditory and tactile oddball paradigms. We also found that the signal quality remained high and impedances did not deteriorate, but instead improved over the course of the day. Regarding wearing comfort, all participants indicated that the fEEGrid was comfortable to wear and did not cause any pain even after 8 h of wearing it. Significance. We show in this report, that high quality EEG signals can be captured with the fEEGrid reliably, even in long-term recording scenarios and with a signal quality that may be considered suitable for online brain-computer Interface applications.
Optimization of harvesting solar cell energy based on MPPT to be applied during the rainy season in the tropics
Authors: Mairizwan  , Anshari Rio , Satria Dewi Wahyuni
Published: May 2020

Energy harvesting systems in solar cells require control to get maximum power, the maximum power control system is maximum power point tracking (MPPT). Energy efficient and effective harvesting is needed to avoid the energy absorbed by the control system. MPPT method with the Perturb and Observe (p&o) algorithm system. P&O method is a change in the value of a certain voltage and looking at the current value, this method is very effective to get the maximum power produced by solar cells. Energy that is absorbed by solar cells during the rainy season is very limited because the intensity and duration of sunlight to the surface of the solar cells is very small, therefore harvesting energy with the MPPT system can produce effective energy.
Genes and physical properties of iron sand from Kinali Pasaman
Authors: Fadhilah  , Prabowo Heri
Published: May 2020

West Coast of Sumatra island has a large amount of iron sand. Research in the Pariaman area and Agam Regency has been carried out, but for the Pasaman area it is not yet available. This research will reveal the iron sand genes found in Kinali Pasaman and find out physical properties such as: Grain size, Magnetization, Specific Gravity and magnetic susceptibility of the samples obtained. The purpose of this study is to provide information and data for the West Pasaman district government to bring in Regional Revenue / PAD (Royalty) as well as one of the solutions for PT Semen Padang in meeting its iron sand needs. The methodology used is to take 5 (five) iron sand samples systematically and represented at several points. The sampling point at the coordinates: 1.S004’46,49 “E99046’6,33”, 2. S005’8,93 “E99046’2,34”, 3.S007’39,40 “E99045’25,60”, 4. S008’20.60 “E99044’55.55”, 5. S008’39.00 “E99044’55.43”. The sample was analyzed for its physical properties at the UNP FT Mining Laboratory. The results of research on the physical properties of iron sand at Kinali Pasaman beach: sample size 0.425mm-0.15mm,% magnetization fraction from size of 0.425mm-0.075mm 20%-40%, specific gravity 2.9-3.5, and susceptibility 497.8-2644, 3 x 10-8m3kg-1 which shows iron sand is superparamagnetic.
Identification of magnetic minerals in the peatlands cores from Lake Diatas West Sumatra, Indonesia
Authors: Sasmita Amelia , Rifai Hamdi , Putra Rizaldi , Aisyah Nur , Phua Marcus , Eisele Steffen , Forni Francesca , de la Maisonneuve Caroline Bouvet
Published: May 2020

Peatlands in Lake Diatas can store various types of minerals. One of the mineral phases that can be found in peatlands are magnetic minerals derived from volcanic eruptions. This study was used to determine concentration of magnetic minerals found in peatlands. We applied the rock magnetism method, measuring the magnetic susceptibility of peat sediments to estimate the concentration of magnetic minerals within a peat core. Bartington Magnetic Susceptibility Meter type MS2C and dual frequency MS2B types, namely 470 Hz and 4.7 k Hz. In this study we analysed the magnetic susceptibility of core Diatas REP B at depths of 0-170 m and 240-720 m. From MS2B the values of low frequency magnetic susceptibility (χif
)and high frequency magnetic susceptibility (χhf
) are obtained. The magnetic susceptibility values ranged from 365,2 × 10−8 m3/kg to 386,8 × 10−8 m3/kg and the value of magnetic susceptibility depends on frequency (%χfds
) range between 0,6 % - 1,3%. These low values indicate that almost no superparamagnetic grains are present. We identified a positive peak in magnetic susceptibility 386,8 × 10−8 m3/kg at 693 cm, whereas the lowest values were messured 365,2 × 10−8 m3/kg at 675 cm. Based on the value of magnetic susceptibility, the dominant magnetic mineral phases are Hematite (Fe2O3) and ilmenite (FeTiO3).
Microwave absorbent properties of Fe3O4 nanoparticle from iron sand prepared by high energy milling ellips-3 dimension
Authors: Diana Sandra Rahma , Ikhsan Muhammad , Yohandri  , Dwiridal Letmi , Ramli Ramli
Published: May 2020

The development of nanoparticles magnetite in the world of research is now very rapid, The purpose of this research was to made Fe3O4 nanoparticles as microwave absorbent material. The Fe3O4 used in this study is magnetic oxide derived from nature in the form of iron sand. Tiram Beach one of the beaches in West Sumatera that contains iron sand exactly at Padang Pariaman District, Sumatera Barat. Nanoparticles Fe3O4 were made using the Higt Energy Milling Ellips-3 Dimenssion (HEM-E3D) method, with variations in milling time for 5, 15, 20, 25 and 30 hours. Fe3O4 nanoparticles are characterized using Vector Network Analyzer (VNA) to see the absorption properties of the microwaves. Analysis VNA result showed that the maximum value of reflection loss obtained in the samples milling 15 hours of -14.775 dB at a frequency of 11.700 GHz.
Digital based sit-up test instrument development
Authors: Saputra Sutrisno , Ihsan Nurul
Published: May 2020

The purpose of this study is to develop a digital-based Sit-Up Test instrument that is effective in use and is efficient in economic terms. This research is a development research with a model design adapted from Borg & Gall. With a population and sample of students of the Faculty of Sport Sciences, Padang State University, amounting to 10 people for small groups and 45 people for large groups, and 5 experts as validators for testing tools. validation. Data was collected using questionnaires and tool trials. Through the test of produck moment validity and reliability test of Test and Retest. The process of development and trial of this tool is done by validating experts by using questionnaires as an instrument of validation and obtained an average percentage of 96%, the results of small group trials obtained a correlation level of 0.99 and reliability tests with direct trials of 0,92 with a very strong reliability category
Chataliytic activity of nano ZnO/Cu for degradation humic acid under ilumination outdoor light
Authors: Mandar Sitiwi , Purnamsari Devi , Zainul Rahadian
Published: May 2020

One of the photocatalysts that is being developed for the degradation of humic acid is ZnO, because it is cheap, easy to obtain and the synthesis process is easy, large size ZnO has several disadvantages such as small surface area and energy band gap which are not suitable when applied to visible light. The research developed a method of making zno in nanometer size and composting to reduce bandgap. The maximum degradation of humic acid at nano ZnO doped Cu 7% which is equal to 54.12%. Nano characterization of nano ZnO doped Cu 7% doping using XRD and DRS UV-Vis spectra was found to be 27 nm and bandgap 5.27 eV.
Optimization of complex NH3 with Cu2+ ions to determine levels of ammonia by UV-Vis spectrophotometer
Authors: Guspita Desy , Ulianas Alizar
Published: May 2020

Ammonia analysis based on complexing ammonia with Cu2+ ions by UV-Vis spectrophotometry. This research aims to obtain uptake at the maximum wavelength of the copper-ammonia complex, optimum conditions and validation of UV-Vis spectrophotometry. The reaction between Cu2+ ions which are blue with ammonia colorless occur in solution to form complex compounds [Cu(NH3)4]2+ dark blue, the maximum absorbance is obtained at a wavelength of 615 nm. Optimization of the ammonia complexing the Cu2+ ions provide optimum conditions a solution of Cu2+ concentrations of 0.01 M in ammonia concentration of 0.04 M, pH 7, and the optimum time to form a complex occurred in the 30th minute and complex compounds can be stable for 90 minutes (± 1 hours 30 minutes). The analytical method validation ammonia using Cu2+ ions provide linear regression equation y = 4,772 x + 0.333 with R2 = 0.989 ammonia concentration range of 0.003 M to 0.08 M; LOD 0.01 M; LOQ 0.04 M; % RSD = 1.32%; and% recovery = 102.03%. The concentration of ammonia in the wastewater sample application obtained the ammonia concentration of 0.04 M. Based on the results of the validation, Ammonia solution with Cu2+ ion as a complex used for the determination of ammonia levels by UV-Vis spectrophotometry.
Analysis of Students Worksheet (LKPD) integrated science with the theme of the motion in life using integrated connected type 21st century learning
Authors: Marshel Joviana , Ratnawulan
Published: May 2020

This research is motivated by the demands of 2013 curriculum in government regulation of education and culture No. 22 of 2016 which requires the educators to design lesson plans and prepare media which suitable with the characteristics of 21st century learning. 21st century learning is learning that integrates literacy, knowledge, skills and attitudes which encourage students to think critically in problem solving, communicative, creative and collaborative (4C) through religious attitudes, cooperation, mutual cooperation, integrity and nationalism, so that the students will have high-level of thinking skills (HOTS). However, the reality in the field found in the preliminary study, the achievement of learning quality is still far from what is expected, it can be seen from the analysis of the Integrated Science LKPD used by students which is still not optimal in facing the challenges of the 21st century. The aim of this study is to analyze learning media in the development of Integrated Science LKPD with the theme of motion in life using integrated connected type 21st century learning. This research is a descriptive study with a qualitative approach. The sample of this study was the students of Junior High School 1 Lubuk Alung. The data used were primary data from interviews and questionnaires. The results of this study are the LKPD used by the school is still not suitable for the 21st century education character (4C). it can be seen from the science LKPD used by the students has not shown the critical thinking skills in solving problems which help them to improve the ability of higher order thinking skill (HOTS), and it also cannot fully help the students to express their conceptual and practical creative ideas.
Preliminary analysis of Edupark Sarasah Kajai Waterfall, Indonesia as a learning resources of works and energy
Authors: Yunita Rika Arni , Rifai Hamdi
Published: May 2020

Sarasah Kajai Waterfall is one of the potential of West Pasaman natural tourism that has been visited by tourists only to enjoy its beauty, even though this tourism are contains many physics concepts that can be used as learning resources for example potential energy. This advantage was not be used by teachers yet to make physics learning more interesting by observing the nature phenomenon directly. Unsuitable teaching materials would make students difficult to understand physics concepts. Therefore, a preliminary analysis of the characteristics of the students, regional potential, teacher competence and teaching material was carried out. This research use Plomp’s Development Model. Data were taken by using questionnaires and interviews teachers and students of SMAN 1 Pasaman and SMAN 2 Pasaman. Preliminary analysis showed that students prefer learning in nature using digital teaching materials. This is used as the basic for the development of digital teaching materials (e-books) based on edupark Sarasah Kajai waterfall as a learning resource in understanding physics concepts Works and Energy.
A meta-analysis study of the use of worksheet (LKS) based on research-based learning models
Authors: Utama Zaka Putra , Festiyed
Published: May 2020

This study aimed to determine the effect of the use (LKS) on the achievement of physical competence of learners. Its influence will be examined from several journals. This study used meta-analysis. Research shows that the use of meta-analysis LKS towards the achievement of more effective learners. The results showed the effect of size on the achievement of students with rigorous of several journals in the effect size obtained is average. It can be proved that the LKS can provide a considerable influence on the achievement of competence of learners.
Development of website on General Physics subject to increase analytical skills of students
Authors: Serevina Vina , Raihanati  , Andriana Wawan
Published: May 2020

This research aims to develop a website on General Physics subject to increase analytical skills of students. Developed website can be used by using computer or smartphone. The ADDIE research method which are Analyzing, Designing, Developing, Implement, and Evaluating. Research was conducted in Laboratory of Media Digital atState University of Jakarta for six months, starts from November 2018 until May 2019 with students of Physics Education Program, State University of Jakarta as object of research. Indicators of analytical skill measured in this research are giving a reasoning, making a conclusion, evaluating a conclusion, predicting a conclusion, considering the validity of an argument, and explaining something using data. Students’ analitycal skill improvement test was conducted by pre-test and post-test in two classes (class A and class B) with n-gain result of class A was 0,66 (medium) and class B was 0,28 (low). Results of validation test showed score 92,30% for material validation, 91,85% for media validation, and 90,37% for learning validation. According to this research result, can be concluded that developed website on general physics subject can increase students’ analytical skill. All of the instruments in this research can be seen at website http://vinnarrai.com
The validity of M-Learning based physics teaching materials to improve student learning access in the digital age
Authors: Amalia Shabrina , Pilendia Dwitri
Published: May 2020

The development of high-quality m-learning based physics teaching materials, needs validity from some experts, so that the product developed can be implemented in physics learning in senior high school. This research has purpose to test the validity of M-Learning based physics teaching materials to improve student learning access in the digital age. The type of this research is Research and Development. The development model used is the development procedure of Thiagarajan (4-D model) includes define, design, develop and disseminate. The assessment instrument used was in the form of a questionnaire consisting of three components, that are content, construct, and language. Based on the result of the study, the result of the feasibility test by expert lecturers and teachers obtained the feasibility of the product with a valid predicate so that it can be used as a source of senior high school physics learning.
Validation of Integrated Science Teacher book with the theme of the Human Body System Adaptation to Temperature Changes using Integrated Type of 21st Century Learning
Authors: Samra Aprili , Ratnawulan
Published: May 2020

This study aims to Determine the validation of the Integrated Natural Science teacher book with the theme senses of sight and optical devices using Integrated Integrated model of 21st Century Learning at the junior high school in Talamau district. This research method used research and development, using Plomp development models. The instrument used was a validation questionnaire. The collection of data validation technique uses a questionnaire that was previously validated by five validators. Data collected was Analyzed using qualitative descriptive through assessment and percentage. Results of analysis of the validation of the Integrated Natural Science teacher book with the theme senses of sight and optical devices using the Connected Integrated model of 21st Century Learning has an average value of 0.88 this is Showed that is developed was valid.
Validity of integrated science teacher’s book on junior high school based on character with the theme of cohesion and adhesion on living with shared model
Authors: Kendedes Tarinta Annisa , Ratnawulan
Published: May 2020

This research was motivated by many obstacles faced by teachers in the use of teachers books processed learning, ideally teacher book that refer to the curriculum 2013 can facilitate teachers in the learning process as well as showing the reference points that will be developed by competency standard of graduates, competency indicators and basic competencies of each subject are then put together in one theme, but actually many teacher books that have not fully facilitated the teacher for the learning process activities, one of which is the material presented has not shown integration between physics, biology and chemistry, the content of the material presented is also concise, making it difficult for the teacher if the material being taught is not the basis. Seeing these conditions, the researchers are interested in developing integrated science teacher books containing character based on shared models, the development of the teachers book is done so that the teacher is assisted in the learning process especially in theme cohesion and adhesion material in the class one on Junior High School. The purpose of this development is to produce integrated science teacher books containing characters with the theme of cohesion and adhesion on living with shared model with valid criteria. This type of research is development research using reeves model with stage analysis of practical problems, design and development the prototype, Iterative cycles of testing and refinement and implementation phase. The result of the development stage was produced by a valid teacher books with a criteria (≥0,6) and used in the implementation stage.
Effectiveness e-authentic assessment in computer network course
Authors: Ambiyar  , Efendi Raimon , Irawati Yuyun , Waskito  , Suryadimal
Published: May 2020

This study aims to identify the quality and effectiveness of the application of authentic web-based assessments in computer network learning on wireless material, and to identify profiles of students’ skills and knowledge competencies in learning computer networks on wireless material. The trial was conducted at the Faculty of Computer Science, University of Dharmas Indonesia. This research uses a descriptive method. The population in this study were students of the Informatics Engineering Study Program. Sampling is done using the purposive sampling method. Based on the results of the study, the quality of authentic assessments showed validity for assessment of performance of 0.94 (high) and reliability of 0.93 (very high), while the validity for the description question was 0.97 (very high) and reliability was 0.98 (very high). Based on observations on the effectiveness of the implementation of authentic assessments and student questionnaires, the level of application of authentic assessments is in categories both at the stage of assessment preparation, implementation of assessment and reflection. The skills competency profile of most students is in very good category, while the knowledge competencies of most students fall into sufficient categories for each indicator of the problem.
Analysis of surrounding gas temperature influence on thermocouple measurement temperature
Authors: Liu Budong , Huang Qinhuang , Wang Peiyong
Published: May 2020

When thermocouple is used to measure high temperature gas flow, the measured temperature, i.e., the thermocouple bead temperature is not exactly the gas temperature. The bead temperature results from the bead energy balance including the convection with the gas flow, the radiation with the environment and the gas, the conduction with the thermocouple wire near the bead. The wire temperature is determined by its own energy balance relating to the gas temperature contacting the wire. Through the wire conduction, the bead temperature is related to the gas temperature around the wire near the bead. The one-dimensional thermocouple heat transfer simulation code was developed and validated by the elaborate experiment. In the current study, this code is used to study the influence of the surrounding gas temperature on the bead temperature. Of course, the gas temperature far away from the bead will not influence the bead temperature. The size of the surrounding region which could influence the bead temperature is identified and its relation with the flow condition and the thermocouple size is analyzed. The quantitative bead temperature variation with the temperature gradient inside this region is studied.
Accurate finite-volume high-order compact interpolation with non-orthogonal and non-uniform grids for computational aeroacoustics
Authors: Uehata Shogo , Yamasaki Nobuhiko
Published: May 2020

In recent years, with the development of supercomputers, the need for engineering applications of computational aeroacoustics is increasing. For industrial applications, the finite-volume compact interpolation is often applied as a discretization method. However, the original finite-volume compact interpolation can be applied only for calculation grids which are orthogonal and uniform, because the original finite-volume compact scheme is formulated assuming that calculation grids are orthogonal and uniform. Indeed, calculation grids for the computational aeroacoustics cannot be limited to orthogonal and uniform. Therefore, the finite-volume compact scheme for arbitrary calculation grids is required. In this paper, the finite-volume NOGS compact scheme is established in three dimensions to be suited for calculations using arbitrary grids. The interpolation error tests were conducted using a number of non-orthogonal and non-uniform grids to verify the NOGS compact scheme. From these interpolation tests, it is revealed that the NOGS compact scheme can reduce the interpolation error compared to the original compact scheme. Therefore, it is predicted that the reduction of the interpolation error leads to accurate evaluation of the numerical flux and that the calculation results are improved. Also, the large eddy simulations around a circular cylinder were conducted to verify the influence of the interpolation error reduction on the flow field and on the sound field.
Development of Hierarchical UAS Traffic Management (UTM) in Taiwan
Authors: Lin Chin E. , Shao P. C.
Published: May 2020

The unmanned aerial vehicles (UAVs) will soon be legally flying into airspace in Taiwan and many countries. UAS traffic management (UTM) becomes an important issue to challenge aviation safety. A hierarchical UTM is proposed and constructed based on the concept of Air Traffic Management (ATM) for the manned aviation system. The proposed Regional UTM (RUTM) and National UTM (NUTM) are hierarchical infrastructure to offers traffic management services for all legal UAV flights in Taipei Flight Information Region (TPE FIR) under and over 400 feet. The proposed UTM provides UAV/pilot log-in/out, flight planning, geo-fencing, detect and avoid (DAA), logbook records, big data analysis, ground control redundant support and controller-pilot communication on multi-window monitor system. UTM data are encrypted to prevent hijacking threat to low altitude UAVs. The UTM adopts ADS-B Like communication infrastructure to offer affordable cost for all UAVs with high reliable surveillance data reporting. The ADS-B Like surveillance mechanism includes 4G/LTE, LoRa, APRS and XBee. Their gateway deployment is designed and constructed with supports of Chung Hua Telecommunication (CHT) in urban and suburban areas. While those remote areas, such as mountain and deep forest, the National Forest Bureau workstation will be selected. The ADS-B Like communication will cover full airspace in Taiwan. Surveillance data reliability, continuity, integrity and availability will be examined by flight tests. The proposed Hierarchical UTM will launch trial runs in Tainan County of RUTM operation to verify the proposed concept, system performance and general operation into the national “UAS Innovative Experiment Project”.
A Study on Stacking Sequence Design of Composite Fan Blades Using Multi-level Optimization
Authors: Sung Y. J. , Jun Y. U. , Park J. S.
Published: May 2020

In this paper, the multi-level optimization method is proposed to design the optimal stacking sequence of composite fan blade more efficiently. The fan blade model used is a laminate with inconsistent stiffness because the thickness is not uniform throughout the model. This feature complicates the optimization problem and makes it difficult to apply optimal design algorithms that use only continuous or discrete variables. For this reason, we conducted the literature survey about combining the optimal design algorithm with continuous and discontinuous variables and developed optimization algorithm for the composite fan blade. Moreover, the design space of discrete variables is reduced through the optimal design of continuous variables. In the first-level, response surface method is used, with the design variables being the volume fraction of plies of the predefined angles of [0°/±45°/90°]. The optimization problem in the first-level aims at minimizing the tip displacement of the fan blade and constraints on other structural responses are imposed. At the second-level, the permutation genetic algorithm is used with the fiber orientation of each ply as design variables. In this level, we perform the optimal design of the stacking sequence using the results determined by prior level, while the composite design rule and compliance constraints are applied.
Direct numerical simulation of a supersonic compression corner
Authors: Wu Zhengyuan , Gao Zhenxun , Jiang Chongwen , Lee Chunhian
Published: May 2020

Direct numerical simulation (DNS) of a supersonic compression corner has been performed using a turbulent-library based inflow generation method, which means adding turbulence fluctuations from preexisted turbulence library files on the current inflow boundary. Illustration of application of such method is given. Physically turbulence boundary layer (TBL) can be obtained after a short distance ‘transition’ process. Qualitative results show that the current numerical simulation is able to obtain the fully developed turbulent boundary layer in the downstream and capture the shock structure well. The accuracy and reliability of current method is proved by the comparison of quantified results between DNS and experimental data. The interaction between the shock wave and the turbulent boundary layer near the corner has been analysed. Turbulent intensity is enhanced passed through the shock and the mean velocity profiles in the separation zone have suffered significant changes.
Simulation on Vortex Induced Vibration of Circular Cylinder
Authors: Chang T J , Lua K B
Published: May 2020

In order to study the vortical flow field and the vibration caused by fluid-structure interaction (FSI), an efficient simulation setup was established. The simulation made use of the built-in Deforming Mesh function, Semi-Implicit Method for Pressure Linked Equations (SIMPLE) Algorithm and SST-kw Turbulence Model of Ansys Fluent to generate the flow field. A User Defined Function (UDF) was written to calculate the displacement of the cylinder based on the simulated flow field information. A range of Reduced Velocity was scanned through in order to find the “locked-in” region, which is the resonance occurring region. The present study focused on the forces acting on the cylinder and the resultant trajectory of different cylinder natural frequencies. The simulation needs further fine tuning to improve the accuracy.
An Interplanetary Mission Design of a Solar Sailing CubeSat to Mars
Authors: Tang Andrew J , Wu Xiaofeng
Published: May 2020

While solar sailing missions have been developed in the past, orbital solar sailing missions are limited in number. Increasing access to the solar system can be achieved by leveraging the potential of solar sailing spacecraft. A feasibility study is performed to analyse a controlled solar sailing mission to Mars using a CubeSat platform. The proposal to send a solar sailing CubeSat to Mars would be revolutionary in delivering small payloads to the red planet by harnessing the solar radiation pressure emitted from the Sun. By utilising solar sailing and aerocapture techniques in the mission design, the need for chemical propulsion for transfer and capture is greatly reduced, minimising launch mass and maximizing payload mass efficiency.

In this study, investigations were carried out as mission analyses in the area of trajectory architecture and subsystem overview for systems available today and in the future. The influence and evolution of trajectories under gravitational and environmental conditions on Mars and the interplanetary transfer were scrutinised individually as relevant restricted dynamic systems. For a chosen insertion orbit, several feasible trajectories to Mars based on different solar sail systems were investigated, including optimised ballistic trajectories and the Sundiver transfer for solar sails. For the interplanetary trajectories, the planetary capture manoeuvre of the spacecraft to a serviceable orbit using aerobraking capture is evaluated. The final trajectory design features minimum-time optimisation for the interplanetary transfer of a solar sailing spacecraft from Earth to Mars. As the selected spacecraft platform is limited to low-thrust solar sailing propulsion, severe performance limitations apply to this mission. This work aims to highlight possible interplanetary trajectories for present and future small satellite platforms despite these limitations by using dynamical orbital simulation models.
Projected changes in hot, dry and wet extreme events’ clusters in CMIP6 multi-model ensemble
Authors: Vogel Martha M , Hauser Mathias , Seneviratne Sonia I
Published: May 2020

Concurrent extreme events, i.e. multi-variate extremes, can be associated with strong impacts. Hence, an understanding of how such events are changing in a warming climate is helpful to avoid some associated climate change impacts and better prepare for them. In this article, we analyse the projected occurrence of hot, dry, and wet extreme events’ clusters in the multi-model ensemble of the 6th phase of the Coupled Model Intercomparison Project (CMIP6). Changes in ‘extreme extremes’, i.e. events with only 1% probability of occurrence in the current climate are analysed, first as univariate extremes, and then when co-occurring with other types of extremes (i.e. events clusters) within the same week, month or year. The projections are analysed for present-day climate (+1 °C) and different levels of additional global warming (+1.5 °C, +2 °C, +3 °C). The results reveal substantial risk of occurrence of extreme events’ clusters of different types across the globe at higher global warming levels. Hotspot regions for hot and dry clusters are mainly found in Brazil, i.e. in the Northeast and the Amazon rain forest, the Mediterranean region, and Southern Africa. Hotspot regions for wet and hot clusters are found in tropical Africa but also in the Sahel region, Indonesia, and in mountainous regions such as the Andes and the Himalaya.
Increasing trend in rapid intensification magnitude of tropical cyclones over the western North Pacific
Authors: Song Jinjie , Duan Yihong , Klotzbach Philip J
Published: May 2020

Rapid intensification (RI) refers to a significant increase in tropical cyclone (TC) intensity over a short period of time. A TC can also undergo multiple RI events during its lifetime, and these RI events pose a significant challenge for operational forecasting. The long-term tendency in RI magnitude of TCs over the western North Pacific is investigated in this study. During 1979–2018, a significant increasing trend is found in RI magnitude, which primarily results from the significant increasing number of strong RI events, defined as 24 h intensity increases of at least 50 kt. Furthermore, there are significantly more (slightly fewer) strong RI occurrences west (east) of 155°E in 1999–2018 than in 1979–1998. Significant increases in strong RI occurrences are located over the region bounded by 10°∼20°N, 120°∼150°E. These changes are likely induced by the warming ocean but appear uncorrelated with changes in the atmospheric environment. By contrast, there are slight decreases in strong RI occurrences over the region bounded by 12.5°∼22.5°N, 155°∼170°E, likely due to the offset between RI-favorable influences of the warming ocean and RI-unfavorable influences of increasing vertical wind shear (VWS).
Intersecting vulnerabilities: climatic and demographic contributions to future population exposure to Aedes-borne viruses in the United States
Authors: Rohat Guillaume , Monaghan Andrew , Hayden Mary H , Ryan Sadie J , Charrière Elodie , Wilhelmi Olga
Published: May 2020

Understanding how climate change and demographic factors may shape future population exposure to viruses such as Zika, dengue, or chikungunya, transmitted by Aedes mosquitoes is essential to improving public health preparedness. In this study, we combine projections of cumulative monthly Aedes-borne virus transmission risk with spatially explicit population projections for vulnerable demographic groups to explore future county-level population exposure across the conterminous United States. We employ a scenario matrix—combinations of climate scenarios (Representative Concentration Pathways) and socioeconomic scenarios (Shared Socioeconomic Pathways)—to assess the full range of uncertainty in emissions, socioeconomic development, and demographic change. Human exposure is projected to increase under most scenarios, up to + 177% at the national scale in 2080 under SSP5*RCP8.5 relative to a historical baseline. Projected exposure changes are predominantly driven by population changes in vulnerable demographic groups, although climate change is also important, particularly in the western region where future exposure would be about 30% lower under RCP2.6 compared to RCP8.5. The results emphasize the crucial role that socioeconomic and demographic change play in shaping future population vulnerability and exposure to Aedes-borne virus transmission risk in the United States, and underline the importance of including socioeconomic scenarios in projections of climate-related vector-borne disease impacts.
Reducing waste on wheat flour packaging: an analysis of Lean Six Sigma
Authors: Sucipto  , Susilowati E , Effendi U
Published: May 2020

Reducing defects in the process of packaging wheat flour is important to be done continuously. This study aims to identify and measure the activity of waste that occurred, performance sigma value, and obtain solutions which do by the researcher in Consumer Packing Division PT Z. Waste is measured and assessed using the methods of Lean Six Sigma and Failure Mode and Effect Analysis (FMEA). Based on research, activity categorized waste activities include Defect, Waiting, Non-Utilizing People’s Talent, Transportation, and Motion. Measurement focused on the largest waste Defect is Broken Pack. The result showed the defect per million opportunities (DPMO) value 4089.2475 with level sigma 4.14 and capability process (Cp) 1.31. FMEA showed eight causes factors of the failure broken pack. Four failure mode of which exceeds the critical value that is less of a response operator (Risk Priority Number or RPN=150), lack of control of packaging (RPN=126), less-skilled workers (RPN = 120) and the inaccuracy of allocating the number of workers (RPN=105). Therefore, on the job training, proper allocation of workers during breaks, the packaging audit of the suppliers, and increase the number of workers needed to support the packaging efficiency of wheat flour.
Some physical and mechanical properties of fermented Keluwak (Pangium edule Reinw) seed
Authors: Hawa L C , Wibisono Y , Roliannisa
Published: May 2020

Fermented seed of the tropical tree Pangium edule Reinw., locally known as Keluwak, have been used as spices in Asian and especially Indonesia cuisine. For further processing and postharvest handling, physical and mechanical properties of the seed are needed. Some physical properties, i.e. length, width, thickness, geometric mean diameter, sphericity, surface area, unit mass and 100-mass of seeds, fraction by weight, true volume, true density, bulk density, porosity, and coefficient of static friction at five different surface (cardboard, stainless steel, iron plate, glass, and plywood) of Keluwak seeds were evaluated at the market moisture content. Also, some mechanical properties, i.e. rupture force, strain, stress and Young modulus at three dimensions axis have been measured. The average length, width, thickness, geometric mean diameter, unit mass and per 100 seeds were 44.94±5.6 mm, 43.35±5.2 mm, 27.40±3.4 mm, 37.36±3.2 mm, 11.47±3.7 g and 1693.39±483.85 g. In the market moisture content, the results indicated 0.87±0.07, 4413.99±733.22 mm2, 1.01±0.01 g/cm3, 0.42±0.03 g/cm3, 58.21±3.37% and 69.10±13.84% for average sphericity, surface area, true density, bulk density, porosity and peel ratio of the seed, respectively. Angle of friction for respective cardboard, stainless steel, iron plate, glass, and plywood were 25.52±6.9 deg, 17.40±3.92 deg, 21.40±5.2 deg, 12.27±42 deg, and 24.8±7.45 deg. The average compressive force needed to break the seed at length, width, and thick axis were 295.34±87.95 N, 283.87±83.90 N, and 215.71±65.53 N. The strain, stress, and Young modulus were 0.095±0.03, 2.10±0.71 N/mm2, and 23.16±7.20 N/mm2 at length axis; 0.069±0.03, 2.66±0.88 N/mm2, and 45.44±20.95 N/mm2 at width axis; 0.05±0.02, 2.05±0.63 N/mm2, and 48.12±22.61 N/mm2 at thick axis, respectively.
Computational fluid dynamics analysis of mini membrane module flow behavior
Authors: Wibisono Y , Migunani Y , Darmanto  , Choiron M A
Published: May 2020

A newly developed green ultrafiltration membrane has been successfully made by utilizing natural antibiofoulant impregnated cellulose acetate mixed matrix membranes. The extract impregnated into cellulose acetate polymer to form mixed matrix membranes with higher and foodgrade antibiofouling properties. In order to evaluate mixed matrix membrane mass transport, a specialized mini membrane modules has been developed. This study utilizing computational fluid dynamics (CFD) simulation to evaluate fluid distribution in rectangular, quadrilateral and circular narrow channels. Three different superficial velocities which are normally found in spiral wound membrane modules were evaluated, i.e. 0.11, 0.16 and 0.2 m/s. Trans-membrane pressure normally used in ultrafiltration processes were evaluated, i.e. 50, 100, and 150 kPa. Based on CFD analysis, circular channel provides a more uniform and distributed velocity stream compare to the others. The circular shape also provide advantage on managing superficial feed flow inside the membrane channel, compared with rectangular and quadrilateral shapes channel. The mini membrane modules potentially reduces laboratory scale research cost, while maintaining the similar operating variables of larger scale.
Prediction of tomatoes maturity using TCS3200 color sensor
Authors: Sandra  , Damayanti R , Hendrawan Y , Susilo B , Oktavia S
Published: May 2020

Vitamin C (ascorbic acid) increased as the maturity advances from green to fully ripe stage and ascorbic acid showed continuously increasing patterns throughout ripening until the red stage. Vitamin C analysis with an invasive method at a laboratory, will cause damage to the sample, require a long time, and can not be used in further measurements. Digital image processing techniques as noninvasive method can predict the maturity of tomatoes and vitamin C non-destructively. The purpose of this study was to design a digital image system to predict tomatoes maturity automatically, simply and practically. RGB digital image and vitamin C content are used as a database system to predict maturity on tomatoes. The performance test used 30 pieces of unripe, medium and ripe tomatoes. The result shows each maturity phase of the tomato has a different RGB value. The Green value decreases with an increasing level of tomato maturity. Red values tend to be the same because tomatoes have a red index from the beginning of their ripeness. From the database of RGB and vitamin C, the equipment shows that unripe level of maturity with RGB values below 10 have vitamin C content about 29.5, medium level of maturity with RGB value between 11-23 have vitamin C content about 33.4, and ripe level with RGB values above 23 have vitamin C content approximately 36.9. The result of the performance test shows that it can detect tomatoes maturity by obtaining a success rate of 93%.
The artificial neural network to predict chlorophyll content of cassava (Manihot esculenta) leaf
Authors: Damayanti R , Sandra  , Dahlena E
Published: May 2020

Artificial neural network (ANN) based prediction system was presented for predicting the leaf population chlorophyll content from cassava leaf images. As the training of this prediction system relied heavily on how well those leaf green pixels were separated from background noises in cassava leaf images, a global thresholding algorithm and an omnidirectional scan noise filtering coupled with the hue histogram statistic method were designed for leaf green pixel extraction. With the obtained of leaf green pixels, the system training was carried out by applying a back-propagation algorithm. The system was tested to predict the chlorophyll content from the cassava leaf images. The purpose of this research was to find the relationship between the color index Red, Green, Blue (RGB); Hue; Saturation HSV; Value; Saturation HSL and Lightness to chlorophyll, and to find the appropriate form of ANN to predict the highest chlorophyll source in cassava leaf based on digital images. The results showed highest positive regression occurred in the saturation HSL index against the total chlorophyll of cassava leaf as much as 78.6%. The best model produced using ANN methods in predicting total chlorophyll is a network model with 8 inputs, 9 hidden layers and one output layer, in the proportion of training data 75% testing data 25% have value result the smallest MSE testing is 0.092 with regression testing of 0.847. Network model can read the highest source of chlorophyll on cassava leaf with the value of 84.68%.
Effect of liquid fertiliser for soil quality and coffee plants’s vegetative growth
Authors: Rahadi B , Lusiana N , Sriwulandari C
Published: May 2020

The aim of this research was to determine the influence of liquid fertiliser that comes from the waste of dairy farms for soil quality and vegetative growth of coffee plants. There are three kinds of fertilization intensity (treatment) that is without fertilization (K0), one-times fertilization (C1) and two-times fertilisation (C2). The results were analysed using Group Randomized Design as experimental design; ANOVA and Tukey Test 5% as analysis method. The results showed that the treatment affects soil quality. The treatment also gives a significant influence (p < 0.05) at the height rate of coffee plants in the 2nd week and the canopy diameter rate of coffee plant in the 2nd and 4th week. The results of this research are expected to provide input especially for cattle farmers and coffee planters who want to integrate their livestock and their crops.
Development of a solar heat assisted egg incubation system
Authors: Paras F O
Published: May 2020

This study is an attempt to provide the poultry industry with an appropriate technology suited for small to medium scale production. The main strategies implemented to enhance energy efficiency were solar assisted heating of the incubation space and intermittent operation of the ventilation device. The study revealed that 72.6% of electrical energy was conserved by using the proposed system. If the prototype was used for balut production, payback period for initial investment is just 10.5 month and annual income would be 3.3 times compared with the income from a conventional system. Response surface methodology was used to characterise the incubation system using a Box and Behnken Design. Response variables were electrical energy consumption and evaporation of water in the incubator. Parameters used in the modelling work were incubator temperature setting, tank water temperature and ventilation port opening. Mathematical models that were generated by the statistical software, Design Expert ®, had a good fit and were validated and was found to be 94% and 98% accurate for predicting electrical energy consumption and evaporation of water, respectively. Numerical optimisation revealed the ideal region of operation for system for incubating duck eggs was at 0% ventilation port opening, incubator temperature setting of 37.5-38°C and tank water temperature of 47.5-60°C. The solar heat collector assisted egg incubation system promotes energy efficiency, utilizes a renewable energy resource, and can also be considered an environmentally sound technology. This study presents tremendous potential for adoption not just for balut production but also for the entire poultry industry.
Effect of ultrasonic assisted extraction on Dayak onion powder extraction (Eleutherine palmifolia)
Authors: Hendrawan Y , Herdiningsih E H , Maharani D M , Hawa L C
Published: May 2020

Dayak onion (Eleutherine palmifolia) is a typical plant of Central Borneo, Indonesia, which contains flavonoids, saponins, polyphenols, alkaloids, glycosides, steroids, phenolic, tannins, triterpenoids, and quinones. It has bioactivity as an antioxidant. Extraction using the ultrasonic assisted extraction (UAE) method can increase phenol compounds and antioxidants in a shorter time. The purpose of this study was to determine the effect of variations in the amplitude and timing of sonication of purified water-based UAE to increase the value of antioxidant activity and the total value of phenol from Dayak onion powder extract. The amplitude variations used in this study were 20%, 35%, and 50%, and the variations of the sonication time used were 5, 10, and 15 minutes. Antioxidant activity was tested using the DPPH (1,1-dyphenyl-2-picrylhydrazyl) method. Total phenol content was tested by the Folin-Ciocalteu method. In the results of this study, the best value for antioxidant activity on Dayak onion powder extract was at a variation of 50% amplitude and 5-minute sonication time, which was 2.433 ± 0.283 mg/ml. While the best value on the test of total phenol of Dayak onion powder extract was at a variation of 35% amplitude and 5-minute sonication time, which was equal to 6.558 ± 1.68 mg GAE/g. Based on the results of ANOVA statistical analysis, it was found that there was a significant effect on increasing antioxidant activity with a significant value of 0.048 on variations in the combination of amplitude and sonication time.