bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of surface modification on Tb doped bismuth ferrite nanofiller in polyvinyl alcohol based composite films
Authors: Halder Monalisa , Meikap Ajit Kumar
Published: May 2020

In this paper, we report the fabrication and the characterizations of surface modified Tb doped bismuth ferrite nanoparticle embedded polyvinyl alcohol (PVA) films. This work begins with the synthesis of Tb doped bismuth ferrite (BTFO) nanoparticles (NPs). BTFO NPs are then functionalized using silanes. Here, the functionalizing agents are tetraethyl orthosilicate (TEOS) and (3-amino propyl) triethoxysilane. Morphological studies confirm that silica coated BTFO NPs possess a distorted hexagonal structure and effectively show less agglomeration. Untreated and functionalized BTFO NPs are embedded in PVA to fabricate flexible polymer nanocomposite systems. After functionalization, BTFO shows uniform dispersion in a PVA matrix. Optical bandgap decreases in functionalized BTFO loaded PVA films due to the increase in charge transfer complexes. BTFO-PVA nanocomposites (treated/untreated) are more thermally stable than the pristine PVA film. The charge carriers of each polymer film follow a correlated barrier hopping conduction mechanism. The outer silica shell thickness of BTFO NPs effectively affects the magnetic property of the films. Enhancement of the magnetic properties is best achieved in the TEOS functionalized BTFO loaded PVA nanocomposite. All the films follow both Ohmic (at lower voltage) and trap controlled space charge limited current (at higher voltage) conduction mechanisms. Considering the effect of intrinsic properties of the polymeric system, the trap controlled current conduction is further well explained by a Poole–Frenkel model. Among the film samples we have examined in this work, TEOS functionalized BTFO–PVA nanocomposite exhibits the best quality in optical, electrical, and magnetic observations.
Theoretical research on the annular intensive relativistic electron motion focused by coaxial cusped periodic permanent magnetic field
Authors: Wu Xiaoling , Chen Changhua , Teng Yan , Wu Ping , Yang Dewen , Wang Dongyang , Li Shuang
Published: May 2020

This paper theoretically investigates the motion characteristics of an annular intensive relativistic electron beam (IREB) in a coaxial, smooth waveguide under a cusped periodic permanent magnetic (CPPM) field. The motion of the electron beam clearly exhibits a periodic oscillation in a CPPM. For the effective transmission of an IREB, the structural parameters of the CPPM must be chosen carefully. Based on theoretical analysis, stability conditions are suggested. The influence of the magnetic field phase, strength, and period on the oscillation amplitude of the beam envelope is analyzed, and the criteria for minimal oscillation amplitude are proposed accordingly. Notably, the theoretical formula, used to predict the oscillation period of the beam envelope, is proposed and verified by single-particle and particle-in-cell simulation results.
Atomistic analysis of radiative recombination rate, Stokes shift, and density of states in c-plane InGaN/GaN quantum wells
Authors: McMahon Joshua M. , Tanner Daniel S. P. , Kioupakis Emmanouil , Schulz Stefan
Published: May 2020

Recent experimental studies have revealed an unusual temperature dependence of the radiative recombination rate in polar InGaN/GaN quantum wells. We show, by direct atomistic evaluation of the radiative recombination rate, that the experimentally observed trend of an increasing rate with increasing temperature results from the population of energetically higher lying electron and hole states with dipole matrix elements larger than those of the band edge states relevant to low temperature studies. Given that the overall evolution of this recombination rate is tightly linked to the energetic distribution of localized states, we investigate the hole density of states and absorption spectra. Based on the calculated absorption spectra, Stokes shift energies are extracted for InGaN quantum wells with In contents ranging from 5% to 25%. Here, good agreement with experimental literature results is found. We provide also hole tail state characteristic energies as a function of the In content, a quantity that indicates the localization character of the ensemble of hole states and which serves often as a key component in modified continuum-based models to capture carrier localization effects in transport or optical gain calculations.
Depletion induced depolarization field in Hf1−xZrxO2 metal-ferroelectric-semiconductor capacitors on germanium
Authors: Zacharaki C. , Tsipas P. , Chaitoglou S. , Evangelou E. K. , Istrate C. M. , Pintilie L. , Dimoulas A.
Published: May 2020

Germanium Metal-Ferroelectric-Semiconductor (MFS) capacitors based on ferroelectric Hf1−xZrxO2 (HZO) with clean, oxide free Ge/HZO interfaces emerge as an interesting layer structure for the fabrication of ferroelectric field effect transistor (FeFET) non-volatile memory devices. It is shown that, at low temperature (<160 K), a semiconductor depletion forms in Ge near the interface, resulting in an increase in coercive voltage by about 2 V, accompanied by a distortion of the ferroelectric hysteresis with subloop asymmetric behavior, which becomes more severe at higher frequencies of measurement. At higher temperatures, the Ge surface near the ferroelectric is easily inverted due to the low energy gap of Ge, providing sufficient screening of the polarization charge by minority free carriers, in which case, nearly ideal, symmetric hysteresis curves are recovered. The depolarization field is experimentally extracted from the coercive voltage and the capacitance measurements, is found to be ∼ 2.2 MV/cm in the low temperature range, comparable to the coercive field, then rapidly decreases at higher temperatures, and effectively diminishes at room temperature. This makes Ge MFSs good candidates for FeFETs for low voltage non-volatile memory with improved reliability.
Effect of topology upon relay synchronization in triplex neuronal networks
Authors: Drauschke Fenja , Sawicki Jakub , Berner Rico , Omelchenko Iryna , Schöll Eckehard
Published: May 2020

Relay synchronization in complex networks is characterized by the synchronization of remote parts of the network due to their interaction via a relay. In multilayer networks, distant layers that are not connected directly can synchronize due to signal propagation via relay layers. In this work, we investigate relay synchronization of partial synchronization patterns like chimera states in three-layer networks of interacting FitzHugh–Nagumo oscillators. We demonstrate that the phenomenon of relay synchronization is robust to topological random inhomogeneities of small-world type in the layer networks. We show that including randomness in the connectivity structure either of the remote network layers or of the relay layer increases the range of interlayer coupling strength where relay synchronization can be observed.
Determining bandgap of black phosphorus using capacitance
Authors: Liu Jialun , Zhou Yujie , Zhu Wenjuan
Published: May 2020

The bandgap of black phosphorus is widely tunable, depending on the number of layers, external electric field, and strain. Since the bandgap of black phosphorus is very narrow, it is difficult to measure using standard photoluminescence and absorption spectroscopy in the visible range. In this paper, we propose a method to extract the bandgap of black phosphorus using capacitance measured at various temperatures and frequencies. From the transition frequency or transition temperature, where C–V changes from high-frequency to low-frequency behavior, we can extract the bandgap information. Using this method, we extracted the bandgap of black phosphorus with a thickness of 50 nm to be 0.30 eV. For comparison, we also extracted the bandgap of black phosphorus using minimum conductance and threshold voltage methods, and the results are consistent with those of the C–V method. This C–V method can overcome the wavelength limitation of the photoluminescence measurement and spatial resolution limitation of Fourier transform infrared spectroscopy. Another advantage of this C–V method is that the extracted bandgap is unaffected by the contact resistance and device area, making it reliable and convenient in determining the bandgap of narrow bandgap materials.
Infructescence and samara morphometrics and potential mechanism of samara release in Allocasuarina and Casuarina (Casuarinaceae)
Authors: Riley Ian T.
Published: May 2020

In addition to samara aerodynamics, mechanisms of samara release will contribute to seed dispersal outcomes. Analysis of species descriptions of Australian members of the Casuarinaceae (sheoaks) indicated cone shrinkage to be a possible mechanism enhancing samara release. However, measurement of cones of nine species of Allocasuarina and Casuarina did not support this hypothesis, but outward movement of samaras both in the field and in oven-dried cones indicated that another mechanism was operating. Microscopic examination revealed that the proximal margins of the bracteoles are involute after drying, and it is postulated that incurving of the bracteoles during drying moves samaras outward against gravity enhancing samara release. This study also revealed inconsistencies in cone and samara metrics between field samples (1–3 specimens for 9 species) and the published descriptions. This could lead to identification uncertainties, and indicates the need to revise the descriptions to more fully encompass the variation in sheoaks across their natural and anthropogenic ranges.
“When I came to the US”
Authors: Wang Ping-Hsuan
Published: May 2020

From a social constructionist perspective, this study examines three gay Indian immigrants’ coming-out narratives as the locus of the discursive construction of both one’s physical and social location within the changing context. It advocates reconceptualizing “coming out” as dynamic and situated in interaction. Also, it investigates the intersection and construction of identities by analyzing coming-out narratives in sociolinguistic interviews conducted in Washington, DC. Drawing on Bamberg’s three levels of positioning (1997), the analysis highlights how narrators bring about their identities as they contrast the social constructs in India, i.e., the absence of such concept, and in the US, e.g., the acceptance of homosexuality, by reenacting dialogue before and after migration. This study adds to positioning theory and contributes to the cross-cultural dimension of research on coming-out narratives. The qualitative analysis also provides a linguistic perspective that views narrating coming out as an interactive process for constructing intersected identities.
Interpreter and Aboriginal Liaison Officer identity construction and positioning
Authors: Karidakis Maria
Published: May 2020

This study employs small story theory (Bamberg, 2006; Bamberg & Georgakopoulou, 2008; Georgakopoulou,
2006, 2015, 2017) and narrative
positioning analysis (Bamberg & Georgakopoulou, 2008) to explore stories that are
told by interpreters of Aboriginal languages and Aboriginal Liaison Officers (ALOs) when they discuss how they do their work and
the challenges they face when interpreting for Aboriginal and Torres Strait Islander patients in hospital settings. Findings
indicate that the interpreters and ALOs draw on stories to contribute their understanding of complexities of interpreting for
Aboriginal patients and do so through the multiple, shifting positions they attribute to themselves as other social actors in the
stories they narrate. These positions are reinforced in the ongoing interaction but are also located across the dataset,
illustrating that capital-D discourses or master narratives are invoked to frame the role, skills and attributes
of the professionals in this study.
Mitochondrial DNA segregation and replication restrict the transmission of detrimental mutation
Authors: Chen Zhe , Wang Zong-Heng , Zhang Guofeng , Bleck Christopher K.E. , Chung Dillon J. , Madison Grey P. , Lindberg Eric , Combs Christian , Balaban Robert S. , Xu Hong
Published: May 2020

Although mitochondrial DNA (mtDNA) is prone to accumulate mutations and lacks conventional DNA repair mechanisms, deleterious mutations are exceedingly rare. How the transmission of detrimental mtDNA mutations is restricted through the maternal lineage is debated. Here, we demonstrate that mitochondrial fission, together with the lack of mtDNA replication, segregate mtDNA into individual organelles in the Drosophila early germarium. After mtDNA segregation, mtDNA transcription begins, which activates respiration. Mitochondria harboring wild-type genomes have functional electron transport chains and propagate more vigorously than mitochondria containing deleterious mutations in hetreoplasmic cells. Therefore, mtDNA expression acts as a stress test for the integrity of mitochondrial genomes and sets the stage for replication competition. Our observations support selective inheritance at the organelle level through a series of developmentally orchestrated mitochondrial processes. We also show that the Balbiani body has a minor role in mtDNA selective inheritance by supplying healthy mitochondria to the pole plasm. These two mechanisms may act synergistically to secure the transmission of functional mtDNA through Drosophila oogenesis.
Amplitude-modulated continuous-wave radar in the terahertz range using lock-in phase measurement
Authors: Dobroiu Adrian , Wakasugi Ryotaka , Shirakawa Yusuke , Suzuki Safumi , Asada Masahiro
Published: May 2020

We present the principle and the experimental verification of a distance measurement method based on the propagation of terahertz waves. The method relies on modulating the amplitude of a resonant-tunneling-diode (RTD) oscillator used as terahertz-wave source and on measuring the phase of the detected wave by applying a quadrature mixing technique. The distance measurement is found to have a residual error as small as 0.063 mm (standard deviation), which is a record for an RTD-based terahertz-wave radar system. This is almost five times better than our previous record of 0.29 mm, when an oscilloscope was used for phase measurements; additionally, the quadrature mixing brings about numerous practical benefits, such as greatly reduced cost, size, weight, complexity, and power consumption.
Anomalous magnetoresistance in detwinned EuFe2As2*
Authors: Xu Zhuang , Pan Junxiang , Tao Zhen , Liu Ruixian , Tan Guotai
Published: May 2020

The in-plane magnetotransport of detwinned EuFe2As2 single crystal has been investigated. In the antiferromagnetic phase of Eu2+ spins, very different magnetoresistance results are observed upon the change of the external magnetic field direction and the current direction. This could be attributed to the tunable orientation of the Eu2+ spins under magnetic field. Electron scattering by spin fluctuation, superzone boundary effect, and cyclotron motion of charge carriers are used to interpret the observed anomalous magnetoresistance which is measured by using a current along a direction. The remarkable features of magnetoresistance suggest that itinerant electrons strongly couple with the spin configuration of Eu2+, which has a huge influence on the transport properties of EuFe2As2.
One-decoy state reference-frame-independent quantum key distribution*
Authors: Li Xiang , Yuan Hua-Wei , Zhang Chun-Mei , Wang Qin
Published: May 2020

Reference-frame-independent quantum key distribution (RFI-QKD) has been proven to be very useful and practical under realistic environment. Here, we present a scheme for one-decoy state RFI-QKD based on the work of Rusca et al. [Appl. Phys. Lett. 112, 171104 (2018)], and carry out investigation on its performance under realistic experimental conditions. Numerical simulation results show that the one-decoy state RFI-QKD can achieve comparable performance in terms of secret key rate and transmission distance as the two-decoy state correspondence under practical experimental conditions. On contrast, it does not need to prepare the vacuum state in the former case, substantially reducing the experimental complexity and random number consumptions. Therefore, our present proposal seems very promising in practical implementations of RFI-QKD.
Design and management of lithium-ion batteries: A perspective from modeling, simulation, and optimization*
Authors: Wang Qian-Kun , Shen Jia-Ni , He Yi-Jun , Ma Zi-Feng
Published: May 2020

Although the lithium-ion batteries (LIBs) have been increasingly applied in consumer electronics, electric vehicles, and smart grid, they still face great challenges from the continuously improving requirements of energy density, power density, service life, and safety. To solve these issues, various studies have been conducted surrounding the battery design and management methods in recent decades. In the hope of providing some inspirations to the research in this field, the state of the art of design and management methods for LIBs are reviewed here from the perspective of process systems engineering. First, different types of battery models are summarized extensively, including electrical model and multi-physics coupled model, and the parameter identification methods are introduced correspondingly. Next, the model based battery design methods are reviewed briefly on three different scales, namely, electrode scale, cell scale, and pack scale. Then, the battery model based battery management methods, especially the state estimation methods with different model types are thoroughly compared. The key science and technology challenges for the development of battery systems engineering are clarified finally.
Implementation of robust constraint inversion method on resistivity geoelectric data to study landslide precursors (case study : Sungai Lasi District and Gunung Talang Solok District, West Sumatra).
Authors: Akmam Akmam , Amir Harman , Putra Amali
Published: May 2020

Landslides are natural disasters that have a major impact on the environment and surrounding communities every year. Even so, the impact of landslides can be reduced if the precursors of landslides are known through research. However, There are not much research has addressed to study this issue thoroughly. Indeed, many methods are used to study landslide precursors, one of which is to study landslide precursors based on resistivity data of rocks that form slopes or hills where landslides tend to occur. The rock resistivity data can be obtained by the Geoelectric Resistivity method, but the resistivity data that obtained through this method is apparent resistivity. The actual rock resistivity and thickness of the rock structure can be interpreted based on apparent resistivity using the Robust Inversion method. Thus, the purpose of this study is to describe the rock structure (resistivity and thickness) which has the potential as a precursor for landslides in Solok Regency, West Sumatra. The results showed that there were 10 landslide precursor points in Sungai Lasi District and 6 landslide precursor points in Gunung Talang sub-district that had the potential for landslides.
Optimization of hydrophobic nanocomposite thin film from silica/polietilen
Authors: Fauzi Ahmad , Zonesya Putri Lathifa , Ratnawulan
Published: May 2020

An optimization of the hydrophobic nanocomposite thin film has been carried out. A thin layer of nanocomposites is synthesized from natural minerals, which are a mixture of silica and polyethylene. Synthesis was carried out using 5 hours spinning with High Energy Milling (HEM-E3D). Optimization is done through variations in the composition of silica minerals with polyethylene. Contact angle characterization was performed using the Nikon D5200 Camera. The results of this study are the optimum contact angle obtained in the composition of silica/polyethylene nanocomposites that is 0.2 gram/0.5 gram.
Fabrication of methacrylate polymer-based on the silica capillary modified with dimethylamine
Authors: Oktavia Budhi , Prasmi Kardi Robi
Published: May 2020

Capillary silica is reacted with the monomer through the externally polymerization process so that a capillary silica polymer will be formed. The formed silica polymer will be modified with dimethylamine as an anion exchange group. Modified silica polymers, their morphological form are characterized by SEM and to see the series of functional groups in polymerized silica polymers will be characterized using FTIR. This research begins with the activation of capillary silica to be used, namely capillary silica with an inner diameter of 0.32 mm. After obtaining the optimum conditions of capillary silica to be used, silica will be reacted with several monomers such as glycydil methacrylate (GMA), azobisisobutyronitrile (AIBN) as an initiator, ethylene dimethacrylate (EDMA) as a crosslinker and porogen 1,4 butanadiol, 1-propanol, and water, by comparison of certain compositions to create a capillary silica polymer. Capillary silica polymers that have been externally polymerized will be modified with dimethylamine (DMA) as an anion exchange group and will be applied as a stationary phase for nitrite and nitrate anion analysis.
Identification of magnetic mineral forming elements in peatland Alahan Panjang West Sumatra Indonesia, section DD REP B 693 using X-Ray Fluorescence
Authors: Ningsih Ella Destari , Putra Rizaldi , La Maisonneuve Caroline De , Phua Marcus , Eisele Steffan , Forni Francesca , Oalmann Jeffrey , Rifai Hamdi
Published: May 2020

The elemental composition in peatland samples has been measured using the XRF (X-Ray Fluorescence) instrument. Peat soil samples were taken using a peat core near the Lake Diatas Alahan Panjang. After the magnetic suceptibilty of the samples were measured using Bartington Magnetic Susceptibility with MS2C sensor the samples that had the highest value were subsequently selected for analysis of elemental composition. The given results of percentage of major composition, including Si (50,552%), Al (13,545%), Fe (12,23%), S (4,896%) and Mg (4,204%). The most magnetic element forming magnetic element was Fe that formed mineral such on hematite, magnetite, maghemite, ilmenite, greidite or geothite.
Using the Schlumberger configuration resistivity geoelectric method to analyze the characteristics of slip surface at Solok
Authors: Rahmani T R , Sari D P , Akmam A , Amir H , Putra A
Published: May 2020

Landslides are the frequent disaster in the wavy topography zone, such as Sungai Lasi Solok. Landslide disaster was difficult to predict. Based on these conditions, we need to do the research. The aims of the research were to find out the characteristic of landslide slip surface at Sungai Lasi Solok base on Geoelectric Data. Data were collected by Automatic Resistivity Multi-electrode using Resistivity Geoelectric Method with Schlumberger configuration. The interpretation of the Geoelectric data was used Two Dimensions Least-Square Inversion Method. Characteristics of the landslide such as were estimated by Trigonometry theory in order to get both the angle and the depth of landslide slip surface. The results of the research are both the angle and the depth of the slip surface is 40 degrees and 14 meters.
Seismic cycle before the main earthquake and the end of time after shocks in West Sumatra
Authors: Savitri F A , Syafriani S , Anggriani F
Published: May 2020

Indonesian archipelago is one of the areas that often experiences earthquakes, this is because Indonesia is located between four plates that move together. One area in Indonesia that is prone to earthquakes is West Sumatra, because West Sumatra is in the vicinity of the active zone. The earthquake that occurred in West Sumatra in the period 2000-2019 had the smallest magnitude of 4.5 SR and the largest magnitude was 7.6 SR. The earthquake in West Sumatra has a Mainshock-Aftershock seismic cycle, an earthquake that begins with a preliminary earthquake and is followed by aftershocks. The suitable method to estimate the end time of aftershocks in West Sumatra is the Utsu method.
Preliminary analysis of physics lab textbooks using project based learning model to improve the scientific skills of high school students
Authors: Anggreni Yosi Dwi , Yohandri
Published: May 2020

Physics lab textbook are guides that can help students in physics practice. According to the 2013 curriculum, physics learning requires students to develop 21st century skills, namely Learning and Innovation Skills. One of the learning models in accordance with the demands of this curriculum is Project Based Learning. Through this learning model, students can develop their skills in critical thinking, creative, collaboration and able to communicate to design experiments to produce products in physics practice. Through physics practicum, students should be able to develop scientific skills. The reality was found out, there was still a lack of physics practicum teaching materials, so physics was studied only theoretically. The study goals are to survey the analysis of the needs of teaching materials in schools that are needed in physics practical. This type of the research is analysis descriptive. The instruments research consist of questionnaires and observation sheet. The result of this study prove that it is necessary to develop teaching materials in the form of practical teaching book based on the Project Based Learning model to improve students scientific skill.
The preliminary study in the development of e-Physics module integrated ethnoscience
Authors: Haspen Cici Dwi Tisa , Syafriani
Published: May 2020

Purpose of curriculum 2013 is to demand actif and independent student in learning. One effort that can be done by teacher is to make an e-modul. By combining technology into the module, it is expected to be able make student more motivated to study physics. In addition, curriculum 2013 also provides opportunities for student to learn through culture. One way to do this is by presenting learning resources (e-modules) with scientific knowledge that is integrated with the surrounding culture or ethnosciens. This research is a descriptive research. Data collection techniques were carried out using interviews and questionnaires. Based on the result of the analysis, it is necessary to develop an e-physics module integrated ethnosciense.
How is the student worksheet design (LAPD) based on project based learning (PjBL) models in Senior High School Physics X learning? Literature review
Authors: Maharani Bahagia , Yohandri
Published: May 2020

Teaching materials can help teachers in-class learning activities because they are composed of learning components and learning materials for students. Student Worksheets (LAPD) Based on Project Based Learning (PjBL) Models in High School X Physics Learning. This research was conducted at Class X High School. The instruments in the form of interviews, questionnaires and observations used a Likert scale. Development of Project-Based Learning (PjBL) based LAPD compiled using the Plomp model. The Arduino Uno microcontroller media development model uses the ADDIE model. LAPD has a category of very validity, practical and effective. Based on the above needs analysis needs the development of Student Worksheets Based on Project Based Learning (PjBL) Models in Senior High School Physics Learning X.
The analysis of high school student’s preparedness to earthquake disaster
Authors: Utia Rahimatul , Fauzi Ahmad
Published: May 2020

A large earthquake has occurred several times in the area of West Sumatra. At present, the potential for earthquakes still threatens the area of West Sumatra. The risk of earthquake disaster can be minimized by mitigating disasters. Mitigation is an effort made to reduce and minimize the consequences of disasters, which include preparedness, alertness and ability. The integration of earthquake disaster material with teaching materials is one of the effective steps in disaster mitigation efforts in the education field. One of the right teaching materials to use in the modern and technologically advanced era is electronic book (e-book). The purpose of this study was to determine the preparedness of students facing earthquake disasters as a preliminary study for the development of high school physics e-book on the theme of earthquakes. This research uses a descriptive method. The study subjects were SMAN 1 Sawahlunto students. The data of the study are primary data obtained from questionnaires using the Likert scale. This study indicates that it is necessary to develop physics e-book on earthquake themes to improve students’ preparedness in facing earthquake disasters.
Validity and practicality of integrated science teaching materials based on Creative Problem Solving model as an efforts for the establishment of anticorruption characters
Authors: Widya  , Indrawati Ena Suma , Muliani Desy Eka
Published: May 2020

The 2013 curriculum was revised with the aim of improving character education and mastery of 21st century skills. One of the skills needed in the 21st century is critical and creative. To generate student creativity, the application of the right model must be carried out. Creative Problem Solving is a model that can increase student creativity, because through this model, students are invited to solve problems through systematic steps. Learning in the classroom should be able to instill character that has an important influence on solving the nation’s problems today. One of the problems of the nation today is corruption. Anti-corruption attitudes need to be given to Indonesian children so that Indonesia in the future become a corruption-freecountry. Type of research is research and development. In this paper specifically discusses the quality of teaching materials developed. Quantitative description is data analysis that used. The results of this study are: 1) the teaching material produced has very valid category, 2) the teaching materials produced has a very practical category.
Effectiveness of student worksheets based guided inquiry on acid base material to improve students higher order thinking skill (HOTS)
Authors: Mawardi Mawardi , Aisyah Fitri Rusiani Js , Yani Fitra Handa
Published: May 2020

One of efforts to improve quality of human resources in 21st century is improve the level of education quality by promoting a new curriculum that is 2013 curriculum. 2013 curriculum adheres to the basic view that learning is not merely a transfer of knowledge and ability, but also to build HOTS of learners. The study aims to find out effectiveness of students worksheets based guided inquiry on acid base material to improve students HOTS. Type of research is quasi experiments with design non-equivalent control class. sampling techniques using cluster purposive sampling. The sample was 127 students consisting of two schools are SMAN 4 Padang and SMAN 8 Padang. Experimental class 1 (n=32 students) and control class 1 (n=32 students) came from SMAN 4 Padang. Experimental Class 2 (n=33 students) and control 2 (n=30 students) came from SMAN 8 Padang. The experimental class used a student worksheets based guided inquiry, while control class used textbooks available at school. Result of this research shows experimental class 1 and control class 1 got N-gain score are 0.64 and 0.58, while experiment class 2 and control class 2 got N-gain score are 0.60 and 0.56 both groups proved to have statistically significant different improvement. It means student worksheets based guided inquiry are increase HOTS students.
Validity and practicality of chemical equilibrium module based on structured inquiry with three levels representation for students grade XI of senior high school
Authors: Nurhasanah  , Azhar M , Ulianas A
Published: May 2020

Chemical equilibrium is an important material for understanding acid base and solubility concept. Based literature and interviews, this material is still considered difficult by student. The learning process that has not presented material with three level representation and interconnects it. Students ability to interconnect the three levels of representation will help students have a good understanding, so that a complete mental model is formed. The aims to develop chemical equilibrium module based structured inquiry with three levels of representation in terms of validity and practicality. The method used Research and Development through the use of Plomp model. The instrument was questionnaire form that consist of validity and practicality sheet. The module was validated by 5 validators. Practicality module was tested by 2 chemistry teachers and 69 students from two of senior high school in Padang. Validity and practicality data were analysed by using the Kappa Cohen formula. The results show that the module had very high degree of both validity (k = 0.82) and practicality (k = 0.91 for teacher response and k = 0.88 for student response). So it can be concluded that the module developed has been valid and practical for use in chemical equilibrium learning.
Implementation of LKPD based on problems assisted by edmodo application to improve student learning motivation in class V students of SDN 19 Nan Sabaris
Authors: Putri Sri Diana , Ulhusna Mishbah , Zakirman
Published: May 2020

Science is one of the compulsory subjects at the elementary school level. Science learning is currently not able to motivate students to be active in learning, and this can be observed at SDN 19 Nan Sabaris. This study aims to see the effect of using problem-based LKPD with the help of applications to improve science learning motivation of fifth grade students of SDN 19 Nan Sabaris. This type of research is quasi-experimental, with a sample of fifth grade students at SDN 19 Nan Sabari, Padang Pariaman Regency. The instrument of data collection in the study was a motivational questionnaire. The data analysis technique uses the t test with the type of paired sample t-test. The results of the data analysis showed the value of sig 2. Tailed for 0.0025 smaller than the alpha value = 0.05, and it can be concluded that there is a significant difference in science learning motivation between before and after the use of problem-based LKPD.
Preliminary study development of student books research based learning to improve student competency in middle school science learning
Authors: Utami Suci Amalia , Usmeldi
Published: May 2020

Student books was used at schools have not undergone development and are still using old learning methods, so there was no development of learning methods. Every time the method of learning and teaching changes which aims to improve student learning competencies so that there are changes in the way of learning which of course also affects the learning outcomes obtained by students. In order to increas for student learning competencies, it is necessary to develop student books which will be integrated with research based learning methods in junior high school science learning. To develop the student book researchers need to carry out preliminary studies. This research method uses descriptive methods. The research subject was the Student’s Book in Middle School Science. The research respondents were students of MTsN 4 Padang Pariaman, MTsS Balah Aie, dan SMP N 1 Patamuan, Padang Pariaman. Research instruments were observation sheets, questionnaires and interview guides that would later be given to science teachers and students. The data analysis technique carried out in this study is qualitative descriptive. The research results obtained will later show an analysis of the learning process included in the low, medium and high categories.
The influence of learning science with constructivist approach towards character building of early childhood
Authors: Hidayati Abna
Published: May 2020

The instilling of character values is one of the priorities in early childhood education which can be obtained from science learning. The aspect of science learning, in its essence, is to acquaint children to the natural environment directly or through the other media. This study has a purpose to discover the impact of science learning with a constructivist approach towards the construction of early childhood’s character. This is experimental research with pre-test and post-test. 15 early childhood students of TK Adzkia II, Tabing, Padang are involved in data collection with total sampling and analyzed with the t-test method. It is found that there has been an influence of learning science towards the building of independent, careful and environmental caring characters for early childhood. The result shows that the average score of mastery of students’ character values is higher after being given science learning with a constructivist approach.
Validity of integrated science teacher’s book with the themes of blood fluid using integrated connected type learning in the 21st century
Authors: Helfira Riza , Ratnawulan  , Syafriani S
Published: May 2020

Teachers in learning in junior high schools use teacher books. In conducting the learning process and the use of student books, the teacher is guided by the teacher’s book. So that the teacher’s book is appropriate for use in learning, the book should be valid. This study aims to determine the validity of the blood fluid teacher’s book using connected type learning integrated learning in the 21st century. This research uses Plomp model development research, while the validation process is carried out in the development phase. Validity data is obtained by using a validity questionnaire. Data were analyzed with a Likert scale and validation values were calculated by the Aiken formula. The results of the teacher validation analysis developed were obtained the book with valid criteria. From the results of the analysis it can be concluded that science teacher books are integrated the theme of blood fluid through learning connected type integrated 21st century skills worthy of being used in the learning process.
Analysis of physics parameters on aerophone musical instruments from Minangkabau as context meaningful learning
Authors: Afrizon R , Dewi W S , Dwiridal L
Published: May 2020

The scientific context as part of scientific literacy becomes the need to apply 21st century skills in learning physics according to the 2013 curriculum. The fundamental problem in this study is the ability of prospective teacher students to design saintific context in the physics material for senior high school grade XI is not optimal despite using a variety of literature and media. This has an impact on student mastery of all physics material of grade XI is still low. The solution offered is the provision of learning resources sourced from local wisdom. The Minangkabau musical instruments are one of the tangible local wisdom related with the physics material for senior high school grade XI, namely sound waves. The purpose of this study was to analyze of physics parameters for aerophone musical instruments from Minangkabau as context of meaningful learning. The type of research to be conducted is qualitative research. This research just arrived at the stage of data analysis Visual Analyser. The aerophone musical instruments from Minangkabau analyzed for physics parameters are “pupuik batang padi”, “bansi”, “sampelong”, and “saluang”. Data collection in this study uses the analysis of the results of the Visual Analyzer simulation and Focus Group of Discussion (FGD). The data analysis technique used is qualitative with three components, namely: data reduction, data presentation, conclusions and verification. The results of the analysis showed that “pupuik batang padi”, “bansi”, “sampelong”, and “saluang” can be categorized into open ended pipes but bansi can be categorized into closed ended pipes according fundamental frequency detected by VA. The conclusion of the research shows that parameters of physics on aerophone musical instruments from Minangkabau fulfill one of the attributes of meaningful learning, namely learning is a process of experiencing because it is related to the natural context and the ability to adapt to the surrounding environment.
Validity of student book development science integrated with blood fluid theme using integrated learning type connected integrated 21st century learning
Authors: Putri Tri Anidya , Wulan Ratna , Syafriani
Published: May 2020

This study aims to determine the validity of integrated science student books with the theme of blood fluidusing a type of connected 21st century learning is integrated into the material used books for independent learning in the learning process for students. This research method uses research and development (R&D). The research instrument used was a questionnaire validation assessment sheet. Data analysis is a descriptive analysis with a Likert scale and validity value is calculated by the Aiken formula. The results of the validation analysis of student books developed obtained a validity value of 0.86 with valid criteria. From the result of the analysis it can be concluded that the integrated science student book with the theme of blood fluid using integrated type 21st century learning can be used in the learning process.
Development of spiritual intelligence values in learning materials of Physics to support reinforcement of character education
Authors: Kamus Zulhendri , Asrizal  , Sari Silvi Atika
Published: May 2020

The learning of physics according to the 2013 curriculum claim a student to practice spiritual attitudes or spiritual intelligence values well. For this objective, the learning material of physics should contain the spiritual intelligence based on physics concept. In fact, the learning material of physics such as books, handout, worksheet and etc have not the spiritual intelligence values. This research has an objective to develop the spiritual intelligence values based on physics concept in the learning material. The type of research method is research and development at the third level that conducts research to develop an existing product, make a product and test the effectiveness of the product. The results of research showed that teaching materials have been produced containing spiritual intelligence values based on physics concepts, teaching material products have very high validity with an average value of 84.96, the use of the product is practical according to teachers and students with an average value of 85, 70 and 82.49, respectively, the use of products in learning activities can increase the achievement of knowledge competencies and spiritual attitudes of students or is called effective for learning physics.
Need analysis to develop science learning material based on thematic teaching by integrating the new literacy
Authors: Yurnetti  , Asrizal  , Murtiani
Published: May 2020

Education in the 21st century must be able to develop the competence of students a holistic and balance form. Integrated teaching is relevant with the 21st century learning paradigm because it is able to encourage active, authentic, holistic and meaningful learning. The 4.0 industrial revolution in the 21st century has demanded teaching to develop a variety of student literacy skills so that they can succeed both in learning and in everyday life. But the application of integrated teaching and the integration of literacy skills in natural science teaching is still limited. Real condition shows that science literacy of Indonesian students is still low. The solution to this problem is to develop the science learning material based on thematic teaching by integrating the new literacy. The purpose of the research was to describe the initial conditions before developing the science learning material based on thematic teaching. This type of research was descriptive research. The research data were analyzed by descriptive statistics. The results of the data analysis stated that: generally the application of thematic learning components is still low, the integration of new literacy components in science teaching and science textbooks can be entered into low category, generally the characteristics of students are good for receiving thematic science learning material, and generally the early literacy of students can be classified into low category. The results of this research provide a good opportunity to develop science learning material based on thematic teaching by integrating new literacy.
Validity of student worksheet based on project based learning models assisted by tracker application for simple harmonic motion experiment
Authors: Lusiana  , Yohandri
Published: May 2020

This research was backgrounded by curriculum 2013’s demand which stated that this curriculum was developed the advanced of technology and information, as well as the internationally educational development. Therefore, an innovation was needed; that was the development of learning model, its source, and its media which were relevant with the demand of curriculum 2013. The innovation was the development of students’ worksheet (LKPD) as one of learning sources which was easily understood by students, the project based learning as one of models recommended by 2013 which could improve students’ competence and creativity, as well as tracker application as a learning media which was IT based that could be internationally competitive. The aim of this research was to produce LKPD based on project based learning equipped tracker application for simple harmonic motion experiment, with a valid, practical and effective criteria. The result of the analysis stage from the beginning to end a chance using tracker application. The result of students’ analysis needed LKPD as a learning source and a project based learning as a model. The result of material analysis which was predominated by the principal and conceptual material. The result of the development stage was gained from LKPD referring to the analysis result. The result of the development stage was produced by a valid LKPD with a criteria (≥0,6) and used in the implementation stage.
Integration conceptual scaffolding in the group investigation: its influence on students’ critical thinking skills
Authors: Koes-H S , Pradana S D S , Suwasono P
Published: May 2020

The enhancement of critical thinking skills (CTS) is one of the learning targets of universities. Although research on enhancing CTS has been achieved, the improvement of CTS through physics instruction is still becoming a problem. This study attempts to find out the integration of conceptual scaffolding to group investigation (GI) and its influence on students’ CTS. This mixed-method research used an explanatory design by involving 59 students in the Fundamental Physics III course in the Department of Physics, State University of Malang. The experimental group received treatment of conceptual scaffolding in GI, whereas the control group received conventional instruction. The instrument used was the prior knowledge test consisting of 17 multiple-choice items (Cronbach Alpha = 0.72) and the tests of CTS consisting of 11 essay items (Cronbach Alpha = 0.67), interview guidelines, and think-aloud protocol. The results of the study show that there are no differences in CTS between the experimental group and the control group. However, for the low prior-knowledge students, CTS of students who use conceptual scaffolding in GI higher than that of students who study with conventional instruction. Low prior-knowledge students who use scaffolding in the GI can use high-level strategies and exhibit more focused actions in solving problems.