bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diffuse Interstellar Bands (DIBs) as a tracer of warp in the Third Galactic Quadrant: Preliminary Results
Authors: Istiqomah A N , Puspitarini L , Arifyanto M I 
Published: June 2019

Abstract
We measured 6613.6 Å diffuse interstellar band (DIB) recorded in the 318 stellar spectra of stars located in the Third Galactic Quadrant. In agreement with previous studies, we found that the DIB strength has a positive correlation with the interstellar extinction, even though significant deviations were found. The correlation study between the DIB strength and the extinction is limited by the fact that the 3D extinction survey in the Galaxy is incomplete. The DIB spatial distribution toward the South Galactic Pole indicates that the DIB carrier(s) are distributed similarly as other Galactic warp tracer. More data, especially DIB measurements from target stars above Galactic principal plane, are needed to demonstrate that DIB can be used as a tracer of Galactic warp.
Photospheric Vector Magnetic Field Parameters as A Predictor of Major Solar Flares
Authors: Nurzaman M Z , Dani T 
Published: June 2019

Abstract
Photospheric vector magnetic field data which have several Space-weather HMI Active Region Patches (SHARP) parameters are used to study active regions that produced major solar flares. SHARP parameter data obtained from the Helioseismic Magnetic Imager (HMI) instruments onboard Solar Dynamics Observatory (SDO) have a good spatial and temporal sampling. We consider three SHARP parameters with high F-scores, namely total unsigned vertical current, total photospheric magnetic free energy, and total unsigned current helicity as a useful predictor for major solar flares. In this paper, we present the data analysis procedure and sample results focusing only on major solar flares (M and X class flares). The preliminary results showed in some cases, one of SHARP parameters for the M-class flare almost has the same value as X-class flare in which ideally should be higher.
Zenithal sky glow measurement in Bandar Lampung as consideration in drafting the regulation of light pollution-free areas around the Lampung Astronomical Observatory (LAO)
Authors: Muztaba R , Saryantono B , Putri A N I , Pratiwi T D 
Published: June 2019

Abstract
Urban development to big cities generally will be accompanied by excessive use of artificial light, such as street lamps, billboards, and building lighting systems. Ineffective and incorrect lighting installation design causes environmental degradation, i.e light pollution. Today, light pollution is one indicator of environmental degradation and energy waste behavior. Study on light pollution has progressed in many fields of science, extending from traditional fields of astronomy to atmospheric physics, environmental science, natural science, and social life. Measurement of sky brightness is also an indicator of the feasibility of an observatory development plan. The location of the observatory is located at coordinates latitude -05° 27′ 71″ and longitude 105° 09′ 39″ with a height of 1030 above mean sea level. The construction of an observatory requires a study of the sky’s brightness conditions as a matter of consideration to obtain the best observation result. Therefore, to support the Lampung Provincial Government, Institut Teknologi Sumatera (ITERA) and Institut Teknologi Bandung (ITB) in carrying out the construction of observatories in TAHURA WAR, Gunung Betung, Lampung. We did the sky brightness measurements as far as 15 km from the location point of the observatory. We use SQM to measure the brightness of the sky towards the zenith in every crowded area in the city of Bandar Lampung. Then, from the measurement results, we make a map of light pollution. From the mapping results, there are four locations that are indicated to be contaminated by light pollution, namely Tanjung Senang, Teluk Betung, Kemiling, and Gedong Tataan with respective values of 15.8 mpas, 16.6 mpas, 16.8 mpas, and 17.00 mpas.
Internet of Things (IoT) For Galactic Cosmic Ray Application Over Astronomical Observatory in Near Future: A Review Study
Authors: Putro W. S. , Muztaba R. , Pratiwi N. , Putri A. N. I. , Birastri W. 
Published: June 2019

AbstractGalactic Cosmic Ray (GCR) it’s very harmful for human life. The Ultra high Neutrino radiation GCR energy from outside galaxy were intimidated Earth and Environmental. The measurement GCR energy using neuron monitor is successful to capture Ultra-high Neutron and Gamma ray, respectively. During Fourth Industrial Revolution (4IR), the current neutron monitor was expanded into Internet of Things (IoT) system to obtain Ultra-high Neutron and Gamma ray in near future. Thus, in this study aimed to develop conceptual study of Neutron Monitor with IoT system over Astronomical Observatory. The result shows Neutron Monitor with IoT system need to deploy in Equator and Antarctic region due to Gamma ray distribution. Here, Neutron Monitor data with IoT system were applied to analyse Natural Hazard potential with predictor from GCR flux parameter. By using auto send status from IoT system, Natural Hazard potential will be updated per-hour into stakeholder (e.g. hospital, Astronautics, and meteorology service). Thus, a disaster victim from Natural Hazard potential caused by Ultra-high Neutron and Gamma ray will be minimized using IoT system during evacuation process in near future.
Possibility of astronomical phenomena to be used to support tourism industry
Authors: Kunjaya C , Melany  , Sukmaraga A A , Arsono T 
Published: June 2019

Abstract
Several astronomical events in the past have shown their potential to attract tourists. This motivates some astronomers and tourism activists to create tourism related events when an interesting astronomical phenomenon occur. The most attractive recent astronomical phenomenon for tourists was the solar eclipse as was proven during the total solar eclipse of March 9, 2016. Similarly, other phenomena such as the lunar eclipse, meteor shower, Mars Opposition have some potential to be exploited as events to attract tourists. Belitong Geopark had organized a sky observation event, for example super blue blood moon event on January 31, 2018 and Mars opposition event on July 21, 2018. It successfully drew attention far and wide, but it needed more effort and creativity to make these events more attractive and marketable. Other cultural heritage sites which contain inherent astronomical tie-in knowledge, such as Borobudur Temple, are also strong prospective to be developed for astro-tourism destinations. In the future, astro-tourism permanent facilities may be developed, for example, sky observation facilities for amateurs in Dark Sky National Park, near Mount Timau National Observatory in Kupang, East Nusa Tenggara Province.
Constraints on the total mass and mass hierarchy of neutrinos from cosmological observations with bayesian analysis
Authors: Emas N P A P , Wulandari H 
Published: June 2019

Abstract
In the standard model neutrinos consist of three species (flavors) and are massless. However, solar neutrino problem that was solved by neutrino oscillations requires that neutrinos have non-zero masses. Another support for non-zero neutrino masses comes from kinematic experiments. Oscillation experiments give rise to a further problem regarding the order of neutrino masses, known as the neutrino mass hierarchy problem, i.e. whether the hierarchy is normal or inverted. On cosmological scales, massive neutrinos affect Cosmic Microwave Background (CMB) and Large Scale Structure (LSS) formation. The impact of massive neutrinos is imprinted in the power spectrum of CMB, and in the LSS matter power spectrum as well. Since neutrinos affect events in the universe, it is possible to constrain neutrino properties based on cosmological observations. This work is aiming at constraining neutrino total mass from cosmological observations in the two hierarchy scenarios, i.e. normal and inverted hierarchies, and also at determining which neutrino mass hierarchy is favoured by cosmological observations. To constrain neutrino total mass we employed CosmoMC and performed Bayesian analysis with MCMC algorithm, while neutrino mass hierarchy was determined based on Bayes factors, in which likelihoods of the two hierarchy scenarios were compared. In addition, neutrino individual masses were estimated by combining results of oscillation experiments. Depending on the dataset used, different total mass constraints were obtained. The tightest constraint comes from a combination of CMB + LSS + BAO + Supernova data, i.e. Σmv
< 0.183 eV (normal hierarchy) and Σmv
< 0.188 eV (inverted hierarchy) with 95% C.L. The Bayes factors analysis prefers normal hierarchy, although with weak evidence.
Loop Quantum Gravity treatment of Charged Black Hole Thermodynamics
Authors: Daas Tirtho 
Published: June 2019

Abstract
This paper aims specifically at answering two contemporary requirements of a quantum theory of gravity, shown by using Loop Quantum Gravity (LQG) theory on the mathematics of black hole thermodynamics by (i) to quantise known classical General Relativistic formulations of black holes using LQG; and (ii) using LQG microstate spacelike sections (holonomies) on established quantum formulations of general relativity like Generalised Uncertainty Principle, to advocate for background independence in the mathematics of black hole horizon as the next step towards a viable quantum theory of gravity.
Identifying changing precipitation extremes in Sub-Saharan Africa with gauge and satellite products
Authors: Harrison Laura , Funk Chris , Peterson Pete 
Published: June 2019

Abstract
Sparse gauge networks in Sub-Saharan Africa (SSA) limit our ability to identify changing precipitation extremes with in situ observations. Given the potential for satellite and satellite-gauge precipitation products to help, we investigate how daily gridded gauge and satellite products compare for seven core climate change precipitation indices. According to a new gauge-only product, the Rainfall Estimates on a Gridded Network (REGEN), there were notable changes in SSA precipitation characteristics between 1950 and 2013 in well-gauged areas. We examine these trends and how these vary for wet, intermediate, and dry areas. For a 31 year period of overlap, we compare REGEN data, other gridded products and three satellite products. Then for 1998–2013, we compare a set of 12 satellite products. Finally, we compare spatial patterns of 1983–2013 trends across all of SSA. Robust 1950–2013 trends indicate that in well-gauged areas extreme events became wetter, particularly in wet areas. Annual totals decreased due to fewer rain days. Between 1983 and 2013 there were positive trends in average precipitation intensity and annual maximum 1 d totals. These trends only represent 15% of SSA, however, and only one tenth of the main wet areas. Unfortunately, gauge and satellite products do not provide consensus for wet area trends. A promising result for identifying regional changes is that numerous satellite products do well at interannual variations in precipitation totals and number of rain days, even as well as some gauge-only products. Products are less accurate for dry spell length and average intensity and least accurate for annual maximum 1 d totals. Tropical Rainfall Measuring Mission Multi-satellite Precipitation Analysis (3B42-V7) and Climate Hazards center Infrared Precipitation with Stations (CHIRPS v2.0) ranked highest for multiple indices. Several products have seemingly unrealistic trends outside of the well-gauged areas that may be due to influence of non-stationary systematic biases. Social media abstract. Sparse data show increasing Africa rainfall extremes and satellite products fill some missing pieces.
Employment of hyper-cycloidal oscillatory motion for finding the coefficient of rolling friction. Part 2: Experimental investigation
Authors: Ciornei F C , Pentiuc R-D , Alaci S , Romanu I C , Irimescu L , Buium F 
Published: June 2019

Abstract
The paper presents a method for finding the characteristics of rolling friction between two cylindrical external surfaces. By choosing the motion between two parallel cylinders it results that a point from one of the cylinders describes a hyper-cycloidal curve when rolling over the other cylinder. The study is focused on the friction in ball bearings. Parts of the ball bearings to be studied are directly involved in materializing the hyper-cycloidal contact. Thus, the immobile circles are materialized by the outer surface of the external ring and the mobile circles are materialized by the spherical surfaces of the balls. The motion of a laser stick attached to the pendulum is filmed. Analyzing the movie, the numerical time dependence of angular amplitude decrease is obtained. The concordance between the experimental and theoretical angular amplitude damping directs to the value of coefficient of rolling friction.
Some aspects regarding the roughness of the railway surface and rolling noise at locomotives
Authors: Babici L M , Tudor A 
Published: June 2019

Abstract
Railway noise is activated by irregularities on the running surfaces of rails and wheels, these being more significant for the most part of the wavelength and the frequency range of interest. The rolling noise generation mechanism consists of two major structural components: the wheel and rail. The contribution to the noise of the track can be further separated into noise radiation on the rails and in the sleepers. To mitigate the rolling noise, these components must be analysed. To direct and manage mitigation methods within Faurei Railway Testing Center, the rail surface roughness in accordance with EN 15610 was determined in a line of alignment, this being a direct method of measuring the surface roughness of the rail, in association with the rolling noise introduction. In this paper, it is proposed a fractal analysis of the microgeometry of the rail surface, with the possibility of using it as an acoustic parameter.
Simulation of Charpy test for different impact velocities
Authors: Musteață A E , Pirvu C , Deleanu L , Georgescu C 
Published: June 2019

Abstract
This paper presents how a finite element model of Charpy sample fails when it is hit with an impactor. Studying the step-by-step evolution of failure of polymeric sample allows for establishing stages of the process characterising the Charpy impact, pointing out processes and phenomena that are difficult to be noticed during the actual impact or by investigating the broken pieces. The simulation was run for different impact velocities (1…3 m/s) and the sample material was considered a bilinear orthotropic hardening model. After analysing the images of the simulations, the following conclusions may be formulated. Simulation helps identifying the stages of the material failure. Using the bilinear hardening model for the polymer failure at low impact velocity (1…3 m/s) gave reasonable simulations. The time for failure process is longer at lower speed and the aspect of the failed surface depends on the impact velocity.
The state of the modular element structure of a prehensor through virtual prototyping
Authors: Frincu I C , Stroe I 
Published: June 2019

Abstract
The paper presents the study of the geometric scheme of the structure of a prehensor module. The prehensor has the role of generating the force required to manipulate an object respecting the prehensor’s plan with the manipulated object. It is proposed the static concept of the prehensor according to the geometric parameters of the prehensat object. Starting from the structural scheme of the proposed module, the 3D component structure is generated using the Catia software. The kinematics of the studied structure is presented and the system modeling prerequisites are created through the Adams program. Importing the system into Adams simulates the kinematics of the proposed structure. The state of stresses and deformations of the prehensor module is determined and presented. The prehensor module of this type is designed for the reliability of the prehensor.
Kinematic Modelling of Contact Point between Chain Bush and Sprocket
Authors: Velicu R , Săulescu R , Gavrilă C C 
Published: June 2019

Abstract
As is well known, in the automotive industry there is a tendency to obtain the most efficient, reliable and compact systems. Because the belt drives used are subject to excessive elongation and wear in most applications, since high performance engines are desired, distribution chains are preferred. The dynamic behavior of a chain drive during operation is directly influenced by its geometry and, implicitly, by the chain contact with the sprocket. Since the application of normal and transverse forces occurring in a chain transmission depends directly on their application point and thus on the point of contact between the chain and the sprocket, the kinematic modeling of the point of contact between the chain bushings and the sprocket is proposed in present paper.
Dynamic optimization of a dual-axis solar tracker for PV modules
Authors: Marcu A , Alexandru C , Barbu I 
Published: June 2019

Abstract
This paper deals with the dynamic optimization of the dual-axis tracking mechanism, which is used for increasing the energetic efficiency of a photovoltaic module, by maximizing the rate of incident solar radiation. The study is based on the optimal design algorithm included in the commercial MBS (Multi-Body Systems) software solution ADAMS, through the parameterization of the virtual model, which offers the possibility to perform a series of studies aiming at identifying the design parameters that decisively influence the dynamic behavior of the tracking systems. The global coordinates of the design points (i.e. the mounting points of the actuating sources) are defined as design variables for the optimization process, while the design objectives refer to the power consumptions of the actuating sources.
High Performance Liquid Chromatography (HPLC) Method for Determination of Isoflavones Content in Shade-Tolerant Soybean Dena I
Authors: Daud Adawiah , Sulistyarti Hermin , Retnowati Rurini , Ginting Erliana 
Published: June 2019

Abstract
Soybeans (Glycine max (L.) Merrill) are the most common source of isoflavones in human foods which useful for health as preventions of cardiovascular disease, cancer, diabetes, hypertension, osteoporosis, and menopause. The amount of isoflavones in soybeans may differ significantly depends on both genetic and environmental factors. Among the four forms of isoflavones, the highest biological activity is indicated by isoflavones aglycones i.e., genistein, daidzein, and glycitein. Genistein and daidzein found as major compounds with significant amounts contained in soybeans. Indonesian Legumes and Tuber Crops Research Institute (ILETRI) cultivate a shade-tolerant soybeans variety called Dena I to overcome the production of soybeans in Indonesia. Although finding exist for Dena I variety, there are no firm data regarding the isoflavones content of this variety. In this research, high performance liquid chromatography (HPLC) method using a C-18 column with UV detection in optimum condition was performed to identify and quantify the isoflavones content in the extract of Dena I soybean. The satisfied separation was obtained using the mobile phase of acetonitrile-acetic acid 0.1% with the gradual increase of acetonitrile 15-30%, the flow rate of 1 mL/min, and detection wavelength of 260 nm. Isoflavone genistein in Dena I extract was eluted at the retention time (tR) of 24.696 min, the same way with the retention time (tR) of standard genistein of 24.490 min. The concentration of genistein was found 0.0524 mg/g Dena I soybean.
Developing a Mickey-Mouse-Designed Microfluidic Paper-Based Analytical Device (μPAD) to Determine The Antioxidant Activity of Green Tea
Authors: Fauziyah Na’ilah , Andini  , Anneke  , Oktavia Ika , Sari Meiria Istiana , Sulistyarti Hermin , Sabarudin Akhmad 
Published: June 2019

Abstract
The determination of the antioxidant activity in green tea using FRAP essays developed in a Microfluidic Paper-Based Analytical Device (μPADs) was observed. μPAD was prepared on the chromatographic paper with a suitable pattern and then printed using a solid ink printer. The solid printing was intended to obtain a hydrophobic barrier and a hydrophilic channel on the chromatographic paper. A preliminary study was done to determine the optimum time and temperature used on the penetration of obtaining the hydrophobic barrier to avoid leakage in the channel. Optimization of temperature and time was calculated by the average velocity, the optimum condition was obtained at 120 °C for 90 seconds with an average speed of 0.1 mm.s−1. The green tea samples were prepared by extracting its active compound using demineralized water at 25 °C and 90 °C with 2 hours of immersion time. For the measurement of antioxidant activities, the analysis was carried out by placing 0.5 μl in the detection zone and 5 μl samples into the sample zone μPAD. Then, the color reaction product, which propagates from the sample zone to the detection zone, is processed by Image J software to measure color intensity in CMYK mode. Extracts of green tea samples at 25 °C and 90 °C has a significant difference in antioxidant activity. These results indicate that the method developed in this work can be used as an alternative method for analyzing antioxidant activity in green tea extract. The results of the average amount of antioxidant activity in green tea samples were shown with Fe2+ concentration. High-speed detection, low cost, high accuracy, and ease of use can be attributed to the advantages of our μPAD method.
Sequential Injection Analysis for Determination of Lead(II) using Extract of Caesalpinia Pulcherrima as a Natural Reagent
Authors: Sabarudin Akhmad , Indrayani Devi Oktavia 
Published: June 2019

Abstract
The lead(II)-contaminated aquatic environment may endanger humans and living organism. The maximum tolerable limit of lead(II) in river water is 1 mg/L. Therefore, the development of a sensitive and green analytical method to determine lead(II) is required. In this work, we developed a Sequential Injection Analysis (SIA) system equipped with a valve-mixing and a flow-based UV detector for highly sensitive detection of lead(II). In order to deal with the green chemistry system, the environmentally friendly natural reagent is prepared from the extract of Caesalpinia pulcherrima instead of a commercial synthetic reagent. The extract of Caesalpinia pulcherrima contains several flavonoid compounds which can bind lead(II) ion to form an orange complex compound at a wavelength of 672.4 nm. Various parameters affecting the sensitivity of the proposed method, which includes pH, reaction time, the flow rate to the detector, and stability of Caesalpinia pulcherrima extract, were investigated in detail. The optimum conditions for a complex formation of Pb-Caesalpinia pilcherrima extract were found at pH 4 along with a reaction time of 10s, and the product flow rate to the detector was 200 µL/s. Under the optimum conditions, a linear calibration graph can be constructed in the lead(II) concentration range of 0-800 ppb with a detection limit of 8.9 ppb. The proposed method is successfully applied to determine lead(II) in industrial wastewater samples with satisfied results.
Numerical Solution of Nonlinear Vibration by Euler-Cromer Method
Authors: Saroja Gancang , Nuriyah Lailatin 
Published: June 2019

Abstract
Nonlinear equations are able to present many behaviours of physical systems better than linear equations. Analytical solutions to nonlinear vibration equations have intractability characteristics, while limitations in computational software resources make it difficult to study systematically the phenomena in many systems. In this paper, the Euler-Cromer method is used to solve numerically the vibration equation nonlinear. The nonlinear vibrations of the equation of harmonic, Van der Pol, and Duffing oscillator motion are used as the physical case models to solve. Simulation results show that the Euler-Cromer method provides a numerical solution that is easy to implement and accurate.