bluuebunny/crossref_metadata_2025 huggingface dataset:
Robust magnetic domain of Pt/Co/Au/Cr2O3/Pt stacked films with a perpendicular exchange bias
Authors: Shiratsuchi Yu , Yoshida Saori , Yoshida Hiroaki , Kotani Yoshinori , Toyoki Kentaro , Nakatani Ryoichi , Mitsumata Chiharu , Nakamura Tetsuya
Published: April 2020

Magnetic domain pattern and magnetic domain wall motion are particularly important to understand the magnetization process. Here, we investigated the magnetization process of perpendicularly exchange-biased Pt/Co/Au/Cr2O3/Pt stacked films based on observations of the magnetic domain. In particular, in contrast to previous studies which use fully exchange-biased state, we used the bi-exchange-biased state. We found that the magnetic domain pattern at the remanent state was robust against magnetic-field cycling, which is relevant to the absence of the training effect. The magnetization process was followed by domain wall propagation in the increasing branch of the magnetization curve. In the decreasing branch, both nucleation of the reversed domain and domain wall propagation were involved. The former was accompanied by latency, suggesting that thermal activation played a significant role in the nucleation of the reversed domain.
Molecular beam epitaxy and characterization of wurtzite ScxAl1−xN
Authors: Wang Ping , Laleyan David Arto , Pandey Ayush , Sun Yi , Mi Zetian
Published: April 2020

We demonstrate the growth of pure wurtzite phase ScxAl1−xN with a Sc composition as high as x = 0.34 on GaN and AlN templates using plasma-assisted molecular beam epitaxy. The wurtzite structure is well maintained even at high growth temperatures up to 900 °C for Sc0.2Al0.8N. Smooth surface morphology (root mean square roughness less than 1 nm) and excellent crystal quality [(002) plane rocking curve full-width at half maximum below 450 arc sec] are achieved over the range of x ≤ 0.34. Optical absorption studies indicate a decreasing bandgap with increasing Sc with a linear relationship of Eg(x) = 6.1 − 3.39x, which is in good agreement with the theoretical prediction. A monotonically tunable refractive index between AlN and GaN is further measured for ScxAl1−xN with various Sc compositions. This work provides a viable path for the epitaxy of wurtzite ScxAl1−xN with high Sc compositions. The distinct effect of substitutional Sc on bandgap and refractive index could be used in designing high-performance optoelectronic, electronic, and piezoelectric devices, and III-nitride integrated photonics and optical cavities.
Room temperature multiferroism in BaCoF4 films prepared by pulsed laser deposition
Authors: Yu Yinghong , Liu Ruobai , Zhao Huihui , Xu Yeming , Li Qi , Du Jun , Xu Qingyu
Published: April 2020

The much lower magnetic ordering temperature of multiferroic fluorides strongly limits their practical applications [J. F. Scott and R. Blinc, J. Phys. 23, 113202 (2011)]. In this paper, (010) oriented BaCoF4 films have been prepared on (0001) Al2O3 substrates by pulsed laser deposition. The clear observation of amplitude and phase hysteresis loops by piezoresponse force microscopy confirms the ferroelectricity at room temperature. In contrast to the antiferromagnetism in bulk BaCoF4 with a much lower Néel temperature of 69.6 K [Eibschütz et al., Phys. Rev. B 6, 2677 (1972)], clear magnetic hysteresis loops are observed in BaCoF4 films, indicating the weak room temperature ferromagnetism. The nearly unchanged saturated ferromagnetic magnetization of about 30 emu/cm3 between 5 K and 300 K suggests that the Curie temperature of BaCoF4 films is much higher than room temperature. Exchange bias is clearly observed, with a blocking temperature of 250 K. Magnetoelectric coupling is demonstrated by the observed magnetocapacitance effect at room temperature.
Experimental study of water thermodynamics up to 1.2 GPa and 473 K
Authors: Dzhavadov L. N. , Brazhkin V. V. , Fomin Yu. D. , Ryzhov V. N. , Tsiok E. N.
Published: April 2020

Water is the most common liquid on the Earth. At the same time, it is the strangest liquid having numerous anomalous properties. For this reason, although water was investigated in numerous studies, many questions still remain unanswered. Even the thermodynamic properties of water at high pressures are unknown. In this paper, we present an experimental study of the thermodynamic properties of water up to a pressure of 12 kbar and a temperature of 473 K far above the range of pressures and temperatures in previous studies. We compare the experimental results to the results of computer simulations of two models of water (SPC/E and TIP4P) and show that the SPC/E model is not appropriate at high pressure, while the TIP4P model describes the equation of state of water, but fails to describe the heat capacity.
Spin–orbit parameters derivation using single-frequency analysis of InGaAs multiple quantum wells in transient spin dynamics regime
Authors: Shida Hiroki , Kawaguchi Kohei , Saito Yasuhito , Takazawa Ichirota , Fukasawa Toshiki , Iizasa Daisuke , Saito Takahito , Kitada Takahiro , Ishitani Yoshihiro , Kohda Makoto , Morita Ken
Published: April 2020

The deriving method of spin–orbit (SO) parameters using a single-frequency analysis was examined in a transient regime of diffusive spin dynamics in InGaAs/InAlAs multiple quantum wells. Transient regime of diffusive spin dynamics is the time regime when the spin precession frequency induced by SO magnetic fields decreases and changes with time. Recently, we have established a method of deriving SO parameters by scanning time-resolved Kerr rotation microscopy in this transient regime [Kawaguchi et al., Appl. Phys. Lett. 115, 172406 (2019)] using the time-dependent spin precession frequency analysis. Although reliable SO parameters were derived, time-independent single-frequency analysis is still attractive because of its simplicity. In this paper, SO parameters’ derivation was performed by the single-frequency analysis comparing the experiment and the Monte Carlo (MC) simulation. The best fit of the simulation to the measurement for the SO-induced frequency yields the derivation of SO parameters; however, the derived values were different from the reliable SO parameters derived by the time-dependent analysis. This discrepancy arises from a spin relaxation time difference between the experiment and MC simulation. After intentionally adjusting the spin relaxation time of the MC simulation to the experiment, the SO-induced frequency obtained by the MC simulation with reliable SO parameters reproduced the experiment well. We found that the spin relaxation time adjustment of the MC simulation to the experiment is necessary to obtain accurate SO parameters from the single-frequency analysis comparing the experiment with the MC simulation.
A low-cost fabrication method of nanostructures by ultraviolet proximity exposing lithography
Authors: Liu Lingpeng , Sun Lei , Qi Liping , Guo Ran , Li Kehong , Yin Zhifu , Wu Dongjiang , Zou Helin
Published: April 2020

The lithography contact/proximity printing technique is widely used in the fabrication of microelectronic components, optical devices, and micro-fluidic chips. However, the fabrication of nano-sized structures requires high-cost equipment. This paper proposes a low-cost method to manufacture nanostructures by ultraviolet proximity exposing lithography through a microphotomask on a conventional lithographic aligner. The influence of exposure distance on photoresist pattern size is studied, and the standing wave effect on the photoresist layer is reduced by post-baking. This cost effective method can be widely applied to fabricate patterns with a nanofeature size.
Suppression of liquid surface instability induced by finite-amplitude oscillation in liquid piston Stirling engine
Authors: Murti P. , Hyodo H. , Biwa T.
Published: April 2020

This study addresses a problem introduced by finite-amplitude oscillations in a liquid piston thermoacoustic Stirling engine and proposes methods to overcome it. After the engine was operated by external heat, the liquid piston oscillated, keeping a flat surface when the amplitude was sufficiently low. However, it became unstable to cause ejection of droplets and formation of air bubbles because the acceleration amplitude exceeded gravitational acceleration. Two methods were proposed to recover the stable liquid surface: one method was the enlargement of the cross-sectional area of the tube around the liquid surface and the other method was the use of submerged polyethylene floats. These methods successfully suppressed the instability of the liquid piston Stirling engine and increased the pressure amplitude by almost twice of the original engine. In addition, adjusting the liquid filling level resulted in the ratio of pressure amplitude over the mean pressure reaching 18% when the acceleration amplitude was elevated to 36m/s2 by the installation of floats. The high-pressure amplitude is an advantage of a liquid piston thermoacoustic Stirling engine over thermoacoustic engines that use only gas as the working fluid.
Phase diagrams classification based on machine learning and phenomenological investigation of physical properties in K1 − xNaxNbO3 thin films
Authors: Liu Duansheng , Bai Gang , Gao Cunfa
Published: April 2020

In this work, we have predicted and classified the temperature-misfit strain phase diagrams of (001)-oriented K1 − xNaxNbO3 (KNN, 0 ≤ x ≤ 0.5) thin films using three classical machine learning algorithms: k-nearest neighbors, support vector machine, and deep neural networks, which have a very excellent prediction accuracy rate of about 99%. Furthermore, various physical properties including ferroelectric, dielectric, piezoelectric, and electrocaloric properties have been calculated and studied based on the phenomenological Landau–Devonshire theory. The calculated results show that the dielectric constant ɛ33, piezoelectric coefficient d33, and isothermal entropy change ΔS of the KNN thin films can be enhanced at the orthorhombic–rhombohedral phase boundary. This work will provide theoretical guidance for experimental studies of KNN thin films.
Asymptotic scaling of drag in flat-plate turbulent boundary layers
Authors: Dixit Shivsai Ajit , Gupta Abhishek , Choudhary Harish , Singh A. K. , Prabhakaran Thara
Published: April 2020

A new asymptotic −1/2 power-law scaling is derived from the momentum integral equation for the drag in flat-plate turbulent boundary layers. In the limit of infinite Reynolds number, the appropriate velocity scale for drag is found to be M/ν, where M is the boundary layer kinematic momentum rate and ν is the fluid kinematic viscosity. Data covering a wide range of Reynolds numbers remarkably collapse to a universal drag curve in the new variables. Two models, discrete and continuous, are proposed for this universal drag curve, and a robust drag estimation method, based on these models, is also presented.
Atomistic study on the dynamic response of the void or helium bubble in aluminum under compression and tension
Authors: Wu Wei-Dong , Shao Jian-Li
Published: April 2020

This work investigates the deformation and dynamic property of the pre-existing void or helium (He) bubble in aluminum (Al) under compression and tension with molecular dynamics simulations, where both the uniaxial and triaxial loadings at a high strain rate are considered. Under compression, the void completely collapses by plastic deformation and after that a recrystallization process is found. The He bubble undergoes a finite collapse because of its internal pressure. Solidification of the He bubble is also observed at a sufficiently high pressure. Moreover, stacking fault tetrahedrons (SFTs) are found under the triaxial compression, instead of the shear dislocation loops under the uniaxial compression. Under tension, the volume of the void or He bubble is nearly proportional to the strain before instability and begins to grow sharply after instability. The instability volumes of the void or He bubble and the corresponding strains approximately satisfy a linear reduction distribution. When the pre-existing void collapses completely, new void nucleation will appear under tension. Interestingly, the triaxial tension produces a large void from the vertex of SFTs, while uniaxial tension produces many small voids at the intersection of the stacking faults. As for the He bubble, it will first be elongated along the tension direction under uniaxial tension. With the increase of tension strain, the void or He bubble grows into an irregular polyhedron and tends to be isotropic for both uniaxial and triaxial tension. In the meantime, the He atoms will deposit on the boundary eventually because the attraction between He and Al is included. In addition, the difference of temperature and pressure between the He bubble and Al matrix is discussed, and an empirical model is proposed to describe the He bubble pressure during the loading process.
Onset of ring defects in n-type Czochralski-grown silicon wafers
Authors: Basnet Rabin , Phang Sieu Pheng , Sun Chang , Rougieux Fiacre E. , Macdonald Daniel
Published: April 2020

This paper presents experimental studies on the formation of ring defects during high-temperature annealing in both electronic-grade and upgraded metallurgical-grade (UMG) Czochralski-grown silicon wafers. Generally, a faster onset of ring defects, or shorter incubation time, was observed in the UMG samples ([Oi] = 6.3 × 1017 cm−3) in comparison to the electronic-grade samples ([Oi] = 3.9 × 1017 cm−3) used in this work. By applying a tabula rasa (TR) treatment prior to annealing, the incubation time can be increased for both types of wafers. We show that TR temperatures above 1000 °C are necessary to effectively dissolve grown-in oxygen precipitate nuclei and limit the subsequent formation of ring defects. A 30 min TR treatment at 1000 °C resulted in the longest incubation time for both types of samples used in this work, as it achieved the best balance between precipitate nuclei dissolution and precipitate re-growth/ripening. Finally, a nitrogen ambient TR step showed a short incubation time for the formation of ring defects in comparison to an oxygen ambient TR step.
Maintenance of broiler performance on commercial diets diluted with copra meal and supplemented with feed enzymes
Authors: Hoffman Mael Sandy , Diarra Siaka Seriba , Devi Ashika
Published: April 2020

Context Dilution of commercial feed with moderate levels of copra meal (CM), a byproduct of coconut oil extraction, was shown to maintain broiler performance in older breeds, but reports on its use in modern fast-growing broilers are limited. Aims We evaluated feed dilution with CM and enzyme supplementation in broiler chickens. We hypothesised that (i) diluting commercial feed with CM will maintain performance of modern fast-growing broilers, and (ii) enzyme supplementation will improve utilisation of the diluted diets. Methods Experiment 1 studied the performance of growing broilers (10–21 days of age) fed commercial grower diet alone (control), or diluted with one of two levels of CM (50 and 100 g/kg) and with or without enzyme supplementation. Cobb 500 broiler chicks (10 days old), 200 in total, were assigned to five dietary treatments with four replicates, in a completely randomised design. Experiment 2 investigated higher levels of dilution (100 and 200 g CM/kg) and enzyme supplementation of commercial finisher diet in 200 finishing broilers (22–42 days of age) assigned to five treatments with four replicates each. Key results In Experiment 1, feed intake was reduced (P < 0.05) on the 100 g CM/kg diet without enzyme compared with 50 g CM/kg without enzyme and both of the enzyme-supplemented diets but was not different (P > 0.05) from the control. Bodyweight gain and feed conversion ratio were not affected (P > 0.05) by dietary treatment. In Experiment 2, feed intake was reduced on 200 g CM/kg with enzyme but did not differ (P > 0.05) among the control and other CM-based diets. Bodyweight gain (P < 0.05) was reduced on the 200 g CM/kg diet without enzyme compared with the 100 g CM/kg diet without enzyme. Feed:gain was not affected (P > 0.05) by diet. The relative weight of carcass and cuts, gut segments and annex organs was not affected (P > 0.05) by diet. Conclusions Diluting commercial grower and finisher diets with 50 and 100 g CM/kg has no adverse effects on performance of modern broilers. At higher levels of dilution (100 and 200 g/kg), enzyme supplementation may be required. Implications These findings will reduce the cost of broiler production and add value to CM in coconut-producing regions. We recommend more research into higher rates of dilution, sources of CM, and enzyme sources and levels that might improve performance and reduce cost of production.
OPEN ARCH: integrated care at the primary–secondary interface for the community-dwelling older person with complex needs
Authors: Mann Jennifer , Quigley Rachel , Harvey Desley , Tait Megan , Williams Gillian , Strivens Edward
Published: April 2020

Optimal care of community-dwelling older Australians with complex needs is a national imperative. Suboptimal care that is reactive, episodic and fragmented, is costly to the health system, can be life threatening to the older person and produces unsustainable carer demands. Health outcomes would be improved if services (health and social) are aligned towards community-based, comprehensive and preventative care. Integrated care is person-focussed in outlook and defies a condition-centric approach to healthcare delivery. Integration is a means to support primary care, with the volume and complexity of patient needs arising from an ageing population. Older Persons Enablement and Rehabilitation for Complex Health Conditions (OPEN ARCH) is a targeted model of care that improves access to specialist assessment and comprehensive care for older persons at risk of functional decline, hospitalisation or institutionalised care. OPEN ARCH was developed with primary care as the central integrating function and is built on four values of quality care: preventative health care provided closer to home; alignment of specialist and generalist care; care coordination and enablement; and primary care capacity building. Through vertical integration at the primary–secondary interface, OPEN ARCH cannot only improve the quality of care for clients, but improves the capacity of primary care to meet the needs of this population.
Transcription profiles of oocytes during maturation and embryos during preimplantation development in vivo in the goat
Authors: Li Yunsheng , Sun Jiangwen , Ling Yinghui , Ming Hao , Chen Zhen , Fang Fugui , Liu Ya , Cao Hongguo , Ding Jianping , Cao Zubing , Zhang Xiaorong , Bondioli Kenneth , Jiang Zongliang , Zhang Yunhai
Published: April 2020

RNA sequencing performed on goat matured oocytes and preimplantation embryos generated invivo enabled us to define the transcriptome for goat preimplantation embryo development. The largest proportion of changes in gene expression in goat was found at the 16-cell stage, not as previously defined at the 8-cell stage, and is later than in other mammalian species. In all, 6482 genes were identified to be significantly differentially expressed across all consecutive developmental stage comparisons, and the important signalling pathways involved in each development transition were determined. In addition, we identified genes that appear to be transcribed only at a specific stage of development. Using weighted gene coexpression network analysis, we found nine stage-specific modules of coexpressed genes that represent the corresponding stage of development. Furthermore, we identified conserved key members (or hub genes) of the goat transcriptional networks. Their association with other embryo genes suggests that they may have important regulatory roles in embryo development. Our cross-mammalian species transcriptomic comparisons demonstrate both conserved and goat-specific features of preimplantation development.
Evolutionary history of modern Samoans
Authors: Harris Daniel N. , Kessler Michael D. , Shetty Amol C. , Weeks Daniel E. , Minster Ryan L. , Browning Sharon , Cochrane Ethan E. , Deka Ranjan , Hawley Nicola L. , Reupena Muagututi‘a Sefuiva , Naseri Take ,   Trans-Omics for Precision Medicine (TOPMed) Consortium,   TOPMed Population Genetics Working Group, McGarvey Stephen T. , O’Connor Timothy D.
Published: April 2020

Archaeological studies estimate the initial settlement of Samoa at 2,750 to 2,880 y ago and identify only limited settlement and human modification to the landscape until about 1,000 to 1,500 y ago. At this point, a complex history of migration is thought to have begun with the arrival of people sharing ancestry with Near Oceanic groups (i.e., Austronesian-speaking and Papuan-speaking groups), and was then followed by the arrival of non-Oceanic groups during European colonialism. However, the specifics of this peopling are not entirely clear from the archaeological and anthropological records, and is therefore a focus of continued debate. To shed additional light on the Samoan population history that this peopling reflects, we employ a population genetic approach to analyze 1,197 Samoan high-coverage whole genomes. We identify population splits between the major Samoan islands and detect asymmetrical gene flow to the capital city. We also find an extreme bottleneck until about 1,000 y ago, which is followed by distinct expansions across the islands and subsequent bottlenecks consistent with European colonization. These results provide for an increased understanding of Samoan population history and the dynamics that inform it, and also demonstrate how rapid demographic processes can shape modern genomes.
The Common European Framework of Reference (CEFR) in French immersion teacher education
Authors: Arnott Stephanie , Vignola Marie-Josée
Published: April 2020

Over 11% of Canadian students are currently enrolled in French immersion (FI) – a program where French is a subject of study and is
the language of instruction in at least two content areas. Research shows that stakeholders in FI initial teacher education (ITE)
programs identify French language proficiency development as an area of high priority; however, Canadian ITE programs do not
typically provide linguistic support. This chapter reports on an adaptation and implementation of the Common European
Framework of Reference (CEFR) (specifically, the European Language Portfolio [ELP]) as part of a
remedial 24-week French writing course in an FSL ITE program focused on developing French proficiency. Student-teachers
(n = 25) and the course instructor identified strengths and challenges associated with this initiative via
surveys and interviews. Findings show participant convergence and divergence on the portfolio experience, raising implications for
decision-making related to its use in ITE programs targeting FI teachers.
Becoming a “language-aware” content teacher
Authors: He Peichang , Lin Angel M.Y.
Published: April 2020

Building on and extending the frameworks of Teacher Language Awareness (TLA) in
second/foreign language education and content-based/CLIL education (Andrews, 2007; Andrews & Lin, 2017; Lindahl & Watkins, 2015), this chapter argues that
effective teaching of academic content in an L2 requires a special kind of
teacher knowledge that goes beyond simple addition of content knowledge and
Knowledge About Language (KAL). Through an ethnographic case study, the
researchers investigated the development of a science teacher’s TLA and teacher
identity through her participation in a school-university collaborative project.
Based on analysis of data from classroom observations, interviews, and lesson
video stimulated commentaries, the researchers have developed a model focusing
on CLIL teacher professional development as a collaborative, dynamic and
dialogic process, where both teachers and teacher educators (TEs) are
co-developing their knowledge and expertise in CLIL.
Teacher adaptations to support students with special education needs in French immersion
Authors: Mady Callie
Published: April 2020

As of late, French immersion (FI) teachers have been encouraged to adapt their instruction to support the inclusion and success of
students with learning difficulties. In particular, pedagogical concepts such as Universal Design for Learning (UDL) (National
Center on Universal Design for Learning, 2014) and differentiated instruction (Tomlinson,
2004) have been promoted as means to do so. This study used observations of nine FI teachers’ classes with the view to
exploring their adaptations for students with learning difficulties in hopes of identifying future professional development
directions. The observations revealed that the FI teachers were aptly adapting their instruction for the class as a whole whereas
they were less apt to modify for individual students. In order to further their inclusive practices, the FI teachers in this study
would benefit from future professional development opportunities that focus on differentiating instruction for individuals and
conversations about if and how teacher language choices can provide additional means of differentiation.
Bulleyaconitine A inhibits the lung inflammation and airway remodeling through restoring Th1/Th2 balance in asthmatic model mice
Authors: Liu Liping , Wang Shuyun , Xing Haiyan , Sun Yuemei , Ding Juan , He Ning
Published: April 2020

The current study aimed to study the effects of Bulleyaconitine A (BLA) on asthma. Asthmatic mice model was established by ovalbumin (OVA) stimulation, and the model mice were treated by BLA. After BLA treatment, the changes in lung and airway resistances, total and differential leukocytes in the bronchoalveolar lavage fluid (BALF) were detected, and the changes in lung inflammation and airway remodeling were observed. Moreover, the secretion of IgE, Th1/Th2-type and IL-17A cytokines in BALF and serum of the asthmatic mice were determined. The resuts showed that BLA attenuated OVA-induced lung and airway resistances, inhibited the inflammatory cell recruitment in BALF and the inflammation and airway remodeling of the asthmatic mice. In addition, BLA suppressed the secretion of IgE, Th2-type cytokines, and IL-17A, but enhanced secretions of Th1-type cytokines in BALF and serum. The current study discovered that BLA inhibited the lung inflammation and airway remodeling via restoring the Th1/Th2 balance in asthmatic mice.
Phytic acid exerts protective effects in cerebral ischemia-reperfusion injury by activating the anti-oxidative protein sestrin2
Authors: Liu Jing , Li Ying , Mei Chunli , Ning Xianbin , Pang Jinfeng , Gu Lei , Wu Liang
Published: April 2020

Cerebral ischemia reperfusion (I/R) is a therapeutic strategy for ischemia; however, it usually causes injury by the aspect of inflammation and neuron apoptosis. This investigation aims to investigate the protective effects of phytic acid (IP6) for cerebral I/R injury in vitro. PC-12 cells under Oxygen and glucose deprivation/reperfusion (OGD/R) were performed to mimic cerebral I/R. IP6 was pretreated before PC-12 cells under OGD/R treatment. The data showed that IP6 activated the expression of sestrin2 in OGD/R injured PC-12 cells. IP6 inhibited OGD/R induced inflammation, oxidative stress, and apoptosis by activating sestrin2. Besides, p38 MAPK may mediate the effects of sestrin2 activated by IP6. Therefore, IP6 can be a potential drug to prevent neurological damage in cerebral I/R injury.
NNT in NSCLC: No need to worry?
Authors: Conrad Marcus
Published: April 2020

In this study, Ward et al. (https://doi.org/10.1084/jem.20191689) provide exciting evidence that nucleotide nicotinamide transhydrogenase (NNT), a mitochondrial matrix–located enzyme harnessing the proton gradient to generate NADPH using NADH, markedly contributes to non-small cell lung carcinoma (NSCLC), which is abrogated in the murine C57BL/6J background, a strain known to be deficient in NNT.
Frequency-dependent reflection of elastic wave from thin bed in porous media*
Authors: Li Hong-Xing , Tao Chun-Hui , Liu Cai , Huang Guang-Nan , Yao Zhen-An
Published: April 2020

The reflection of elastic wave from thin bed in porous media is important for oil and gas reservoir seismic exploration. The equations for calculating frequency-dependent reflection amplitude versus incident angle (FDAVA) from thin bed in porous media are obtained based on porous media theory. Some conclusions are obtained from numerical analysis, specifically, slow compression wave may be ignored when considering boundary conditions in most situations; the dispersion of reflection from thin bed is much higher than that from thick layer and is periodic in frequency domain, which is affected by the thickness of thin bed, velocity, and incident angle; the reflection amplitude envelope in frequency domain decays exponentially, which is affected by the thickness of thin bed, attenuation, and incident angle; the reflection amplitude increases with thickness of thin bed increasing, and then it decreases when the thickness reaches to a quarter of wavelength.
An artificial synapse by superlattice-like phase-change material for low-power brain-inspired computing*
Authors: Hu Qing , Dong Boyi , Wang Lun , Huang Enming , Tong Hao , He Yuhui , Xu Min , Miao Xiangshui
Published: April 2020

Phase-change material (PCM) is generating widespread interest as a new candidate for artificial synapses in bio-inspired computer systems. However, the amorphization process of PCM devices tends to be abrupt, unlike continuous synaptic depression. The relatively large power consumption and poor analog behavior of PCM devices greatly limit their applications. Here, we fabricate a GeTe/Sb2Te3 superlattice-like PCM device which allows a progressive RESET process. Our devices feature low-power consumption operation and potential high-density integration, which can effectively simulate biological synaptic characteristics. The programming energy can be further reduced by properly selecting the resistance range and operating method. The fabricated devices are implemented in both artificial neural networks (ANN) and convolutional neural network (CNN) simulations, demonstrating high accuracy in brain-like pattern recognition.
Google forms utilization for student satisfaction survey towards quality of service at Universitas Muhammadiyah Tasikmalaya
Authors: Nurmahmudah Endah , Nuryuniarti Rissa
Published: April 2020

Research on the survey of student satisfaction with service quality at Universitas Muhammadiyah Tasikmalaya (UMTAS) was conducted in July 2019. This study aims to determine the level of student satisfaction with the quality of services at UMTAS. With multiple linear regression methods and using total sampling technique, the entire population is the object of research. The population in this study were all semester 4 UMTAS students. In this case the distribution and filling out the questionnaire as a data collection tool using Google Forms. The researcher only informs the address of the shortlink that has been made, namely bit.ly/2WZtLr7 to the respondent, and the respondent can access the link from their respective Android phones. The results of this study indicate that the level of student satisfaction with 5 variables has a simultaneous and partial influence of 86.6%. Based on the partial t count, the most influential is the tangible variable but all indicators have the same effect on student satisfaction significantly. While the rest (13.2%) is influenced by other variables not examined in this study.
Sample Identification Approach by K-Means Clustering In Thinner Retail Market Segmentation
Authors: Listiyoko Langgeng , Purno Marhaendro
Published: April 2020

Ingredients identification of thinner sample in retail market is very easy to do by a special machine, and then the product would be copied. Then the problem is how to set the sample of competitor product into the segmentation based on many consideration aspects. Data mining helps user to identify whether the sample is a member of one segmentation or not based on the closest characteristic value that observed. K-means clustering calculate a numeric value of each sample product’s characteristic then classify into a number desired cluster. Data history has 21 existing products and classified into 4 cluster at the beginning, then two data tests (competitor products) put into the data set to identify what is the nearest cluster. The result of K-means clustering shows the first competitor as cluster_1 while the second one is cluster_3.
Learning Mathematics “Asyik” with Youtube Educative Media
Authors: Sari W N , Samosir B S , Sahara N , Agustina L , Anita Y
Published: April 2020

The research aims to find out how the use of YouTube Educative as education media by students, parents, and teachers in improving knowledge, skills, and creativity generally in education and especially in mathematics studies. Besides that research also recommend YouTube Educative to help students so that learning mathematics becomes fun. This study applied descriptive qualitative research.This study applied descriptive qualitative research. The subjects of this study were the principal (headmaster), students and mathematics teachers. The object of this research was YouTube. The results of the study found that principal (headmaster), teachers, and students had not taken the advantages of YouTube as educative media in mathematics learning activities. Youtube is mostly used for playing games, watching cartoons, funny videos, arts and cooking recipes. Recommendation related to the use of YouTube Educative help students more easily understand concepts and learn mathematics becomes more fun.
Candidate Selection of Athletes Sparring for Boy Category Pencak Silat Using TOPSIS: Case Study in PSHT Pencak Silat
Authors: Putro Sigit Susanto , Santoso Wildan Romadhoni , Husni  , Rachmad Aeri
Published: April 2020

Pencak silat is one of the original cultures of the Indonesian people. But the general champion of the pencak silat branch is no longer dominated by Indonesia. Therefore, to be able to compete with other universities or overseas athletes, there needs to be a strict selection from each region. There are 22 criteria used for the selection of prospective sparring athletes. Therefore it is necessary to have a system that can facilitate the trainer to choose students to be sent to compete on behalf of the branches of each class. This study uses the TOPSIS (Technique For Order Preference By Similarity To Ideal Solution) method for student ranking and is selected as needed. Testing is done by the system and comparing the results of the competition from 12 sessions consisting of class A, class B, class C and class D with 42 athlete candidates. The suitability level of this application is 66.67%.
The Application of Genetic Algorithms as an Optimization Step in The Case of Nurse Scheduling at the Bringkoning Community Health Center
Authors: Mala Sari Rochman Eka , Rachmad Aeri , Imamah  , Santosa Iwan , Husni
Published: April 2020

Scheduling is an important activity that must be done in every job. In scheduling, there must be some rules that can minimize the occurrence of conflicts or gaps between schedules. In this study, applied a genetic algorithm to solve the problem of scheduling nurses in Bringkoning community health center. In the process of genetic algorithm, there are several processes that must exist until the creation of a result is a schedule. The number of nurses, population length, Cr and Mr values, and also number of iterations along with the number of days determined by input. The crossover method used is one cut-point crossover, Random mutation method and selected with elitism selection. Thereby, the analysis gained, is the value of the parameter genetic algorithm affects the optimization results. The small parameter size will cause the search area of the genetic algorithm to be narrower, whereas if the parameter size is too large it will require longer computing time and does not guarantee it will result in an optimal value for some of those variables. So, it depends on number of days in the input to get optimal result of the schedule for nursing care in the room of the emergency unit.

A post-publication change was made to this article on 20 Apr 2020 as the previously published article was a duplicate.
Evaluation model of students learning outcome using k-means algorithm
Authors: Henderi  , Sunarya Abas , Zakaria  , Nurmika Sri Linggawati , Asmainah Nur
Published: April 2020

The progress of students learning outcomes have to evaluated and make monitor. Student learning outcomes were indicated by score of the exam. Educational institutions can determine the ability of students’ knowledge and competences based on student exam scores. For this reason, the goals of this research is develops an evaluation model of student learning outcomes. The model was developed using k-means algorithm and it has functions to analyze the student learning outcomes. The model was tested by conducted using 50 data exam of students, rapid manner software, and has implemented by the Python 3.0 programming language. The testing the evaluation model of student learning outcomes that were developed resulted: there are 3 clusters of student learning outcomes that are good, satisfying, and lacking. The tested results also showed that 40% of students had good learning outcomes, 44% of students were satisfactory, and 16% of other students had poor learning outcomes. The results of testing the student learning evaluation model can be used by the parties concerned to make decisions related to work programs or formulate steps that need to be taken to improve student learning outcomes.
Analysis of Knowledge Management System in Grabb Mobile Application Based On Usability
Authors: Thoyyibah T. , Leslie Hendric Spits Warnars Harco , Trisetyarso Agung , abdurachman Edi , Lumban Gaol Ford , Soewito Benfano
Published: April 2020

Grabb mobile application is a tool that is often used by people to travel. Each will travel then grabb will be ordered and pickup in front of the house and delivered to the destination location according to the address written on the application. Much knowledge can be disseminated through this Grabb application. Among them Grabbb car when going to go using a car, grabbike, service and others. The method in this study uses the adoption of a knowledge management system life cycle (KMSLC). Where the stages used are consists of Analysis of Existing Infrastructure Evaluation, Knowledge Capture, Implement the KM system, Evaluation. The steps taken are system analysis, knowledge mapping in the application, the results of implementation and evaluation using usability with 10 respondents through the adoption of Software Usability Measurement Inventory (SUMI). The results of SUMI’s Usability are effectiveness with a value of 90, efficiency 70 and satisfaction 70. By looking at these results, the mobile grabb application is included in the good category because the value of usabililty is above average.

A post-publication change was made to this article on 20 Apr 2020 as the previously published article was a duplicate.
Factors for the implementation of electronic certification on small traditional boats and fishing vessels in Indonesia.
Authors: Saputra Diaz , Trisetyarso Agung
Published: April 2020

On September 2019, Directorate General of Sea Transportation, the government who in charge for the safe operation of ships in Indonesia, has introduced a new model of ship certification form. It is an electronic certificate that is used for traditional boat and fishing vessel of less than 7 gross tonnage. This electronic certificate is for the first time being applied to a ship in Indonesia. This marks a new era for ship certification in Indonesia. The conventional paper format of certification had been applied before it was changed to electronic certification.

Indonesia is implementing electronic certificates on traditional vessels and fishing vessels of less than 7 gross tonnage due to several reasons. The first is the need for durable form material due to lifetime validation of certificates. The second due to problems related to misuse of previous type of conventional paper format certificates that caused difficulties in determining the number of this type of vessels in Indonesia.
Implementation of Fuzzy Mamdani For Recommended Tourist Locations In Madura - Indonesia
Authors: Mala Sari Rochman Eka , Pratama Ifan , Husni  , Rachmad Aeri
Published: April 2020

As a developing country, Indonesia is currently actively developing itself in all its main fields of tourism. Diversity of tourism in Indonesia, one of which is located on Madura Island which has approximately 60 attractions spread across four districts namely Bangkalan, Sampang, Pamekasan and Sumenep. However, the current condition, there are many attractions that are not explored in the outside community so that many tourists do not know which attractions are revised. This study focuses on how to make a decision support system that provides tourist attractions for tourists. The method used is Fuzzy Mamdani which can produce the best decision by determining the Min-Max value and finding the fuzzy value based on its center. This research succeeded in making a system that provides tourist attraction recommendations for tourists by using fuzzy mamdani based on three criteria, namely the number of visitors, the distance of the tourist location to the city center, and the review of visitors on the internet.

A post-publication change was made to this article on 20 Apr 2020 as the previously published article was a duplicate.
Working tool redesign to reduce ergonomic risk of salt evaporation field workers based on RULA and REBA assessments using esMOCA Instrument
Authors: Arendra Anis , Akhmad Sabarudin , Mu’alim  , Lumintu Ida
Published: April 2020

What are the ergonomic risks of Indonesian salt evaporation field workers especially in Madura? This problem has not been much noticed, though salt production from Madura is the largest contributor to national salt production. This study aims to assess the level of ergonomic risk of salt evaporation field workers in Madura. Conduct ergonomic risk analysis and reduce the level of ergonomic risk through redesigning work tools with the REBA and RULA approaches. REBA and RULA assessments are conducted with esMOCA instrument application. This research shows that five activities of salt evaporation field workers pose a high ergonomic risk with a REBA and RULA score above 6. These five activities are, chopping salt deposits on salt field, scraping salt deposits on salt field, collecting and pile up salt deposits, picking up salt to the carrying basket, and packing salt into sack. One of these five activities, picking up salt activity poses the highest ergonomic risk with REBA score 11. Efforts undertaken to reduce risk were made by replacing shovel tool with pan hoe tool, REBA score dropped to 5.
Text Categorization with Fractional Gradient Descent Support Vector Machine
Authors: Hapsari Dian Puspita , Utoyo Imam , Purnami Santi Wulan
Published: April 2020

Text documents on the web are an incredible resource including one example of big data, large size and so many variations that it becomes difficult for humans to choose meaningful information without the help of a computer. Text categorization job is to automatically classify text documents into standards class based on their content. The objective of this research is to implement a classifier with optimization based on the Fractional Gradient Descent in text classification. In our research, we propose using the Fractional Gradient Descent to optimize the SVM classifier so that it can increase the speed of training data. We explore a batch of different training data to compare the speed of the UCI ML text dataset training process with the SVM- SGD and SVM-FGD classifiers. This research concludes that using SVM-FGD will optimize the training time for text dataset in the activity of data classification.
TransJoin: An Algorithm to Implement Division Operator of Relational Algebra in Structured Query Language
Authors: Imamuddin A , Nahar I , Chandra S
Published: April 2020

Division operator is one of operators in Relational Algebra which is not implemented directly in SQL (Structured Query Language) standard. Therefore it is not be able to retrieve division query results with an SQL statement in the current relational database management systems (RDBMS). Database programmers have to create a complicated query to perform the task. It is the only relational algebra operators which is not implemented in ANSI SQL standard. This research aimed to study and design an algorithm named TransJoin (transformation and join) to implement it in SQL. TransJoin works to relation P(x, y) divided by Q(y) resulted R(x) through grouping and transforming each y attribute becomes P’(x, y’) and Q’(y’) and each x value is a single tuple with y’ is a composite value of y. Then, result R(x) is resulted of joining P’(x, y’) and Q’(y’) relations by matching y’ attribute. TransJoin was implemented in an open source RDBMS SQLLite. TransJoin tested and delivered valid results by comparing of traditional SQL queries and our proposed SQL queries with various data. The research showed that our algorithm is much more efficient by consuming 0.078 milliseconds compared contrasted the traditional query in 1,974.08 milliseconds for 9,991 tuples.
Evaluation of Decision Tree, K-NN, Naive Bayes and SVM with MWMOTE on UCI Dataset
Authors: Untoro Meida Cahyo , Praseptiawan Mugi , Widianingsih Mastuti , Ashari Ilham Firman , Afriansyah Aidil , Oktafianto
Published: April 2020

Imbalanced data causes misclassification because the majority of the dominant data is in the minority data, which results in a decrease in the value of accuracy. UCI dataset is a public dataset that can be used as a dataset in machine learning. This study aims to evaluate the Decision Tree, K-NN, Naive Bayes, and Support Vector Machine classification methods on data imbalances in MWMOTE. MWMOTE is used in resolving Imbalanced cases through weighting and grouping. This goal is achieved by evaluating the Decision Tree, K-NN, Naive Bayes, and Support Vector Machine classification methods in MWMOTE to produce more representative synthetic data and increase the accuracy value. The results obtained from this study indicate that the Decision Tree has higher evaluations of recall, precision, F-measure, and accuracy compared to K-NN, Naive Bayes, and Support Vector Machine for data that are balanced with MWMOTE.
Forward Selection Technique to Choose the Best Features in Prediction of Student Academic Performance Based on Naïve Bayes
Authors: Saifudin A , Ekawati  , Yulianti  , Desyani T
Published: April 2020

Supervision of academic performance is very important to ensure that students can complete their education on time. There have been many proposed applications of machine learning algorithms to predict students’ academic performance. Prediction is done by analyzing a dataset of historical academic of the student’s grade. The dataset which analyzed has many variables (features), this can increase complexity and decrease model performance because maybe not all features are relevant. We propose to implement the forward selection algorithm to select features that can improve model performance. The result shows that the performance of predictive models of students academic scores can improve with the application of feature selection.
Feature Selection Techniques to Choose the Best Features for Parkinsons Disease Predictions Based on Decision Tree
Authors: Yulianti  , Syapariyah A N , Saifudin A , Desyani T.
Published: April 2020

Parkinson is a disease that is caused by nerve cell damage in the brain and incurable. Knowing about Parkinson disease is very important so that medical action can be taken to prevent Parkinson’s getting worse. The dataset that uses to analysis for Parkinson disease using machine learning algorithms has many features. The dataset with many features can increase complexity, but not all features have a positive influence on the results of the analysis. Irrelevant features can reduce model performance. This research proposes to apply feature selection to choose features that have a positive effect so that the performance of the model does not decrease. The experiment results show that the application of feature selection can lead to better model performance.