bluuebunny/crossref_metadata_2025 huggingface dataset:
Distinct electrostatic frequency tuning rates for amide I and amide I′ vibrations
Authors: Chelius Kevin , Wat Jacob H. , Phadkule Amala , Reppert Mike
Published: October 2021

Amide I spectroscopy probes the backbone C=O stretch vibrations of peptides and proteins. Amide I spectra are often collected in deuterated water (D2O) since this provides a cleaner background in the amide I frequency range; such data are often referred to as amide I′ spectra since deuteration induces changes in the mode structure, including a roughly ∼10 cm−1 redshift. For biological samples, however, deuteration is often not possible. As amide I frequency maps are increasingly applied to quantitative protein structural analysis, this raises the interesting challenge of drawing direct connections between amide I and amide I′ data. We here analyze amide I and amide I′ peak frequencies for a series of dipeptides and related compounds. Changes in protonation state induce large electrostatic shifts in the peak frequencies, allowing us to amass a sizable library of data points for direct amide I/amide I′ comparison. While we find an excellent linear correlation between amide I and amide I′ peak frequencies, the deuteration-induced shift is smaller for more red-shifted vibrations, indicating different electrostatic tuning rates in the two solvents. H2O/D2O shifts were negligible for proline-containing dipeptides that lack exchangeable amide hydrogens, indicating that the intrinsic properties of the solvent do not strongly influence the H/D shift. These findings indicate that the distinct tuning rates observed for the two vibrations arise from modifications to the intrinsic properties of the amide bond and provide (at least for solvated dipeptides) a simple, linear “map” for translating between amide I and amide I′ frequencies.
Breaking the symmetry of spin-sublattices in antiferromagnet by interfacial tailoring in the L1-MnPt/NaCl/Fe junction
Authors: Tong Junwei , Wu Yanzhao , Ruan Liuxia , Yang Bo , Xie Guangming , Qin Gaowu , Tian Fubo , Zhang Xianmin
Published: October 2021

The detection of magnetization states of the antiferromagnets is a precondition to read the binary bits (0 and 1) for the magnetic recording. The magnetoresistance effect has been utilized to detect the magnetization states in commercially ferromagnetic spintronic devices. However, reading the magnetization states of antiferromagnets is extremely hard because of the absence of net magnetic moment in the antiferromagnetic materials. Here, to generate the tunneling magnetoresistance effect in an antiferromagnetic device with the compensated surface, a method of interlayer selection and interfacial tailoring was proposed to break the symmetry of spin-sublattices in antiferromagnets. The stacking structure of the device is L10-MnPt/NaCl/Fe. The C-type antiferromagnet L10-MnPt was used as the antiferromagnetic electrode, and Fe was the other electrode. NaCl was selected as the barrier layer to break the symmetry of spin-sublattices in L10-MnPt by considering the lattice constants of different materials. It is confirmed that the device with the Mn terminal shows the C4v symmetry in which the spin-sublattices symmetry of L10-MnPt was broken. As a result, the tunneling magnetoresistance ratio of the present device can be up to 200%, which is much larger than the reported ratios of both anisotropic magnetoresistance and the spin Hall magnetoresistance effect in the antiferromagnetic devices, showing a great potential application to read the magnetization states of the antiferromagnetic devices. The spin-dependent transport mechanism of the present device was analyzed in detail by the kǁ-resolved transmission and the local density of states. This study would be beneficial to promote the development of antiferromagnetic spintronics.
Chaos patterned metasurface absorber with multi-peak and broadband
Authors: Du Junsa , Zhang Pin , Qiu Leilei , Gao Xiaohui , Huang Shengxiang , He Longhui , Deng Lianwen
Published: October 2021

A chaos patterned metasurface absorber (CPMA) with three strong absorption peaks and a wide bandwidth has been designed. This CPMA presents a single-layer sandwich structure, which not only enables easy optimization by adjusting the surface pattern and model size but also contributes to the continuous effective bandwidth (EBW, with an absorptivity larger than 90%) from the multiple adjacent absorption peaks. The continuous EBW is from 4.28 to 9.56 GHz with a bandwidth of 76.3%. Meanwhile, analyses on the distributions of the surface current, electric field, and power loss density illustrate that the absorption mechanisms are mainly magnetic coupling resonance and dielectric loss. The experimental results confirm the good absorption performance with multi-peak and wide bandwidth for the fabricated CPMA sample, which shows potential applications in the field of anti-electromagnetic interference.
Spatio-temporal evolution mechanism of cavitation vortex ropes in a swirling flow
Authors: Li Deyou , Ren Zhipeng , Yu Liang , Yang Qi , Wang Hongjie
Published: October 2021

Cavitation vortex rope widely occurs in hydraulic machinery, leading to the decrease in performance characteristic and increase in pressure fluctuation. The objective of this study was to explore the generation and transformation of cavitation vortex ropes in a swirling flow. A visual swirling-flow generator platform was designed to investigate their spatiotemporal evolution mechanism. A flow pattern observation system with a high-speed camera was built to capture the vortex rope forms, and pressure fluctuation experiments were carried out to present fluctuating characteristics of corresponding cavitation vortex ropes. Cavitation vortex rope forms and pressure fluctuation characteristic under different operating conditions were exhibited. Four types of stable cavitation vortex ropes (broken, dual, single, and subulate) were observed. Regional distribution of vortex ropes under different Reynolds and cavitation numbers was characterized, which showed that broken and subulate vortex ropes account in large Reynolds and cavitation ranges. Pressure fluctuation analyses revealed dominant characteristic frequencies were 2.13, 1.98, 1.74, and 1.93 times the rotational frequency of the runner for the broken, dual, single, and subulate cavitation vortex ropes, respectively. In addition, two unstable transitions were identified during the conversion process. One is an unstable transitional triple-vortex rope during from a dual- to single-vortex rope process, and the other is an unstable subulate-vortex rope between the occurrence of the single- and stable subulate-vortex ropes. The present study could give a deep understanding of the generation of cavitation vortex ropes and provide some references to improve the hydraulic instabilities induced by cavitation vortex ropes in hydraulic machinery.
Real-space characterization of tetragonal CuO epitaxial films
Authors: Zhong Yong , Dou Ziyuan , Wang Rui-Feng , Lv Yan-Feng , Han Sha , Yan Hang , Song Can-Li , Ma Xu-Cun , Xue Qi-Kun
Published: October 2021

It is widely believed that the undoped Mott insulator is crucial to understand the origin of high-TC superconductivity and the complex phase diagram in cuprates. Tetragonal CuO, the simplest structure among cuprates, is regarded as an archetypal model to explore the ground state physics of Mott insulator. Here, we report on the epitaxial growth and surface characterization of tetragonal CuO thin film by combining ozone-assisted molecular beam epitaxy and multi-analytical techniques. In situ scanning tunneling microscopy measurement reveals two sets of Cu2+ square lattices with a reversed contrast of their apparent heights between neighboring domains. A spectroscopy study demonstrates an upper bound of the charge transfer gap as 3.68 eV, and quantitatively agrees with the previous photoemission and x-ray photoelectron results. Our work will deepen the understanding of high-energy electronic structures in parent cuprates.
Painting the postfoundational picture
Authors: Declercq Jana , Macgilchrist Felicitas , Vandendaele Astrid , Jacobs Geert
Published: October 2021

This introductory chapter lays the ontological and
epistemological groundwork for this book, by providing a review
of its key themes and concepts, and outlining the book’s theoretical and
methodological position. More specifically, the book’s topic is introduced
based on a number of data points from the contributing chapters. These point
to the ubiquity of participation, engagement and collaboration, but also to
the tension they potentially create, including in the context of newsmaking. To
understand the key concepts in this central argument, two bodies of
literature are discussed. We first delineate
how we understand newsmaking, and focus on a number of recent changes in
this domain that are relevant for our central argument, such as that
newsmaking is increasingly engaging with a number of communities and
professional stakeholders, and that user-generated content and audience
feedback have become central. Second, the literature on participation,
engagement and collaboration is reviewed, exploring how predominant these
concepts have become in many realms of life, and how they are often related
to democratic ideals. Subsequently, we argue for the relevance of a
postfoundational perspective, and for the value of fieldwork approaches.
“It is, perhaps more than ever before, a matter of participation”
Authors: Jacobs Thomas , Jacobs Geert
Published: October 2021

This chapter presents a discourse-analytical approach to
a series of blogposts uploaded to the website of Brussels-based libertarian
think tank between 2015 and 2018 in reaction to the controversy over the
Transatlantic Trade and Investment Partnership (TTIP). In these blogposts,
economic experts and professionals reflect about how to successfully
persuade the public of the case for free trade. We argue that these
blogposts rest on two ultimately incompatible ontologies – one founded in
economic science, the other based on a rudimentarily constructionist
understanding of media and the public debate. The tension generated by the
clash of these ontologies turns the blogposts into an interesting example of
the negotiation of professional identities at a time when participation,
collaboration and engagement are increasingly getting sedimented as the
baseline for newsmaking practices.
Building an intersubjective understanding of the patient’s mental
suffering
Authors: Weiste Elina
Published: October 2021

The experience of suffering may result in a breakdown of
commonly shared meaning, namely the disintegration of
intersubjectivity. This article investigates patients’ expressions
of suffering and professionals’ attempts to maintain intersubjective
understanding in interactions that are conducted in psychiatric
outpatient care. The analysis demonstrates that patients’
expressions of suffering involve a strong emotional experience and a
particular kind of passivity: tolerance of agonising pain and
endurance of what is unbearable. For their part, professionals
attempt to verbalise and explain the patient’s experience in order
to build a shared world of meaning. The article argues that by
locating suffering in the symptoms of an illness, professionals
structure suffering into a medical problem. This enables them to
suggest appropriate treatment options aimed at eliminating
suffering.
A case study of a quadrilingual child
Authors: Håkansson Gisela , Waters Birgitta
Published: October 2021

This paper reports on a case study of a quadrilingual child, Stefan, born and raised in Sweden and exposed to four languages before his first birthday: English, French, Russian and Swedish. We examine his vocabularies in these languages by the Cross-Linguistic Lexical Tasks (Haman, Łuniewska, & Pomiechowska, 2015), designed to measure vocabulary in monolingual and multilingual children. Stefan’s scores on comprehension and production reveal proficiency in all his languages, to varying degrees, and with comprehension exceeding production. While highlighting direct and indirect exposure as explanation for the variation in proficiency, we also discuss cognate vocabulary as an important factor for multilingual language development. In the production tasks, Stefan demonstrates not only vocabulary knowledge but also language-specific use of morphosyntax.
Crosslinguistic nonword repetition and narrative performance over time
Authors: Boerma Tessel , Blom Elma
Published: October 2021

Previous research has shown that a crosslinguistic nonword repetition and narrative tasks can support the identification of developmental language disorder (DLD) in 5- and 6-year-old bilingual children. The tasks disentangled the effects of DLD and bilingualism and demonstrated good clinical validity. The present longitudinal study investigated whether similar results could be obtained at older ages by following the same children over a three-year period. The tasks were found to remain sensitive to DLD and insensitive to bilingualism. The magnitude of the effect of DLD decreased over time. Together, the instruments attained adequate diagnostic accuracy in a monolingual and bilingual group at each wave of testing, indicating that they can effectively identify DLD in different learning contexts and at different ages.
Cell cycle–independent integration of stress signals by Xbp1 promotes Non-G1/G0 quiescence entry
Authors: Argüello-Miranda Orlando , Marchand Ashley J. , Kennedy Taylor , Russo Marielle A.X. , Noh Jungsik
Published: October 2021

Cellular quiescence is a nonproliferative state required for cell survival under stress and during development. In most quiescent cells, proliferation is stopped in a reversible state of low Cdk1 kinase activity; in many organisms, however, quiescent states with high-Cdk1 activity can also be established through still uncharacterized stress or developmental mechanisms. Here, we used a microfluidics approach coupled to phenotypic classification by machine learning to identify stress pathways associated with starvation-triggered high-Cdk1 quiescent states in Saccharomyces cerevisiae. We found that low- and high-Cdk1 quiescent states shared a core of stress-associated processes, such as autophagy, protein aggregation, and mitochondrial up-regulation, but differed in the nuclear accumulation of the stress transcription factors Xbp1, Gln3, and Sfp1. The decision between low- or high-Cdk1 quiescence was controlled by cell cycle–independent accumulation of Xbp1, which acted as a time-delayed integrator of the duration of stress stimuli. Our results show how cell cycle–independent stress-activated factors promote cellular quiescence outside G1/G0.
Cnm1: A bridge between mitochondria and nuclear ER
Authors: Casler Jason C. , Lackner Laura L.
Published: October 2021

Few membrane contact sites have been defined at the molecular level. By using a high-throughput, microscopy-based screen, Eisenberg-Bord, Zung et al. (2021. J. Cell Biol.https://doi.org/10.1083/jcb.202104100) identify Cnm1 as a novel tethering protein that mediates contact between mitochondria and the nuclear ER in response to phospholipid levels.
Enhancing the photoluminescence response of thick Ge-on-Si layers using photonic crystals
Authors: Yurasov D V , Yablonskiy A N , Baidakova N A , Shaleev M V , Rodyakina E E , Dyakov S A , Novikov A V
Published: October 2021

More than an order of magnitude enhancement of the room-temperature photoluminescence (PL) signal from rather thick germanium layers grown on Si(001) was obtained through the utilization of 2D photonic crystals (PhCs). A set of PhCs with different periods and filling factors was fabricated and studied using micro-PL spectroscopy. Optical features of the fabricated PhCs were also theoretically modeled using rigorously coupled wave analysis, which allowed us to bring the observed peaks in the PL response into correlation with the different modes of PhC. In particular, we were able to associate the well-resolved peaks in the PL spectra with the optically active modes of the PhCs. The obtained results proved the possibility of using a homogeneously distributed active medium in PhCs without the formation of specially designed cavities in order to redistribute the internal emitted light into the required modes and efficiently extract it in the far field. The relative simplicity and higher tolerance to fabrication imperfections, as well as the large working area of these kinds of PhCs compared to PhCs with microcavities, can be advantageous for creating a PhC-based Si-compatible light source for the telecom band.
Cascaded PT-symmetric artificial sheets: multimodal manipulation of self-dual emitter-absorber singularities, and unidirectional and bidirectional reflectionless transparencies
Authors: Yang Minye , Ye Zhilu , Farhat Mohamed , Chen Pai-Yen
Published: October 2021

We introduce cascaded parity-time (PT)-symmetric artificial sheets (e.g. metasurfaces or frequency selective surfaces) that may exhibit multiple higher-order laser-absorber modes and bidirectional reflectionless transmission resonances within the PT-broken phase, as well as a unidirectional reflectionless transmission resonance associated with the exceptional point (EP). We derive the explicit expressions of the gain–loss parameter required for obtaining these modes and their intriguing physical properties. By exploiting the cascaded PT structures, the gain–loss threshold for the self-dual laser-absorber operation can be remarkably lowered, while the EP remains unaltered. We further study interferometric sensing based on such a multimodal laser-absorber and demonstrate that its sensitivity may be exceptionally high and proportional to the number of metasurfaces along the light propagation direction.
Circular dichroism assisted bi-directional absorbers
Authors: Cheng Yang , Li Yongfeng , Wang He , Wang Jiafu , Qin Zhe , Qu Shaobo
Published: October 2021

Chirality, a geometric property that is of great importance in chemistry, biology, and medicine, has spurred many breakthroughs in the field of multi-dimensional metasurfaces that provide efficient ways of flexibly manipulating amplitude and phase of circular polarization (CP) waves. As one of the most important applications, chiral metamaterials can be used to implement novel absorbers. Herein, an ultra-thin wideband circular dichroic asymmetric metasurface was implemented via loading resistive film into chiral resonators. Opposite and reversible polarization conversion and circular dichroism (CD) were realized as being illuminated by CP waves from both sides meanwhile. Theoretical derivation and simulation verify that the polarization conversion and CD enhancement utilizing multi-layer CD metasurface. It is also found that the orientation angle of the meta-atom of each layer plays an important role in the CD enhancement, which paves a new way for CD enhancement. In addition, the coupling between the CD resonators was utilized to manipulate CD. On this basis, an ultra-thin polarization-insensitive absorber was achieved by employing a C4 2 × 2 CD resonator array, which was identical illuminating from front and back sides. Circular dichroic absorbers possess great potential in practical applications, ranging from stealth technology, antenna isolation, multi-functional microwave devices, chiral sensing, and catalysis.
A thin and optically transparent infrared-radar compatible stealth structure with low emissivity and broadband absorption
Authors: Tan Xiaoxue , Chen Juan , Li Jianxing
Published: October 2021

In this paper, an optically transparent structure that combines broadband absorption and low infrared (IR) emissivity for dual-band stealth is proposed. The whole structure includes two functional layers. The periodic resistive film of the upper functional layer acts on IR stealth. Its emissivity in the IR band of 8–14 μm is lower than 0.25. Another functional layer achieves greater than 90% wide absorption from 6 to 18.5 GHz. The whole optically transparent composite structure has a low profile of 0.141λ
0, where λ
0 is the wavelength of free space at the center frequency. It has absorptivity that is greater than 90% in the region of 5.7–16.5 GHz and has wide angular stability. The measured result is consistent with the simulation, which verifies the performance of the proposal. The IR-radar compatible stealth structure proposed in this paper has potential applications in the field of multi-spectrum compatible stealth.
High-density magnetic-vacancy inclusion in Co2MnGa single crystal probed by spin-polarized positron annihilation spectroscopy
Authors: Miyashita A , Maekawa M , Shimoyama Y , Seko N , Kawasuso A , Umetsu R Y
Published: October 2021

Co2MnGa is a Weyl semimetal exhibiting giant anomalous Hall and Nernst effects. Using spin-polarized positron annihilation spectroscopy, we examined a Bridgman-grown Co2MnGa single crystal with a nearly perfect L21-ordered structure and a reference Co2MnAl polycrystal with a Mn–Al-disordered B2 structure. We found that a large amount of magnetic vacancies (more than 100 ppm) were included in the Co2MnGa crystal but not the Co2MnAl crystal. We discuss possible reasons for the inclusion of vacancies, the role of vacancies in the development of the ordered structure, and the electronic states associated with the vacancies. Toward the development of Co2MnGa-based devices, the manners for reducing vacancies as well as the influence of vacancies on the electrical transport properties should be considered.
Spontaneous emission in inertial and dissipative nematic liquid crystals: the role of critical phenomena
Authors: Nascimento J H , Pinheiro F A , Silva Neto M B
Published: October 2021

We develop a rigorous, field-theoretical approach to the study of spontaneous emission in inertial and dissipative nematic liquid crystals (LCs), disclosing an alternative application of the massive Stückelberg gauge theory to describe critical phenomena in these systems. This approach allows one not only to unveil the role of phase transitions in the spontaneous emission in LCs but also to make quantitative predictions for quantum emission in realistic nematics of current scientific and technological interest in the field of metamaterials. Specifically, we predict that one can switch on and off quantum emission in LCs by varying the temperature in the vicinities of the crystalline-to-nematic phase transition, for both the inertial and dissipative cases. We also predict from first principles the value of the critical exponent that characterizes such a transition, which we show not only to be independent of the inertial or dissipative dynamics, but also to be in good agreement with experiments. We determine the orientation of the dipole moment of the emitter relative to the nematic director that inhibits spontaneous emission, paving the way to achieve directionality of the emitted radiation, a result that could be applied in tuneable photonic devices such as metasurfaces and tuneable light sources.
An approach to determine solution properties in micro pipes by near-field microwave microscopy
Authors: Wang Yahui , Wei Ziqian , Chen Yujie , Zhou Quanxin , Gong Yubin , Zeng Baoqing , Wu Zhe
Published: October 2021

In this article, we propose a quantitative, non-destructive and noninvasive approach to obtain electromagnetic properties of liquid specimens utilizing a home-designed near-field microwave microscopy. The responses of aqueous solutions can be acquired with varying concentrations, types (CaCl2, MgCl2, KCl and NaCl) and tip–sample distances. An electromagnetic simulation model also successfully predicts the behaviors of saline samples. For a certain type of solutions with varying concentrations, the results are concaves with different bottoms, and the symmetric graphs of concave extractions can clearly identify different specimens. Moreover, we obtain electromagnetic images of capillaries with various saline solutions, as well as a Photinia × fraseri Dress leaf.
Coordinated design of the cartridge-type blanket and the ceramic pebble divertor for the helical reactor FFHR-b3
Authors: Miyazawa J. , Goto T. , Hamaji Y. , Kobayashi M.I.
Published: October 2021

The cartridge-type blanket for the helical reactor has been updated and named the CARDISTRY-B3. Together with this, the ceramic pebble ergodic limiter/divertor system named the REVOLVER-D3 has been adopted in the design. There was a difficulty in fabricating the blanket cartridges due to the first wall shape with three-dimensional surface. This difficulty has been removed by introducing the slit first wall, where the first wall surface is formed by alternately stacking solid metal plates and porous plates made of metal or ceramic. The liquid metal flowing inside the blanket cartridge oozes out through the porous plates and forms the surface flow covering the first wall. Solid target plates for the helical divertor has been omitted, because the divertor region is already covered and protected by the liquid metal surface flow. The liquid metal freely falls inside the blanket cartridges by the gravity force and then exhausted to the pool set on the lower port. The ceramic pebbles, which are dropped to the inboard-side ergodic layer to form the flowing limiter divertor, also flow into the liquid metal pool. The pebbles and liquid metal are individually elevated again by screw conveyers. Since the free surface of the liquid metal is exposed to the plasma, the vapor pressure of the working liquid metal should be low enough. Ternary or quadruple alloys, which include Li, Sn, Pb (or Bi), and Er, have been selected as the candidates of the functional liquid metal for the CARDISTRY-B3 that satisfies the requirements of low vapor pressure, low density, low melting point, and high tritium breeding ratio. In this study, the coordinated design of CARDISTRY-B3 and REVOLVER-D3 for the FFHR-b3 is presented. The FFHR-b3 is one of the design options that aims at demonstration of 100 MW net electricity with two times larger devise size than LHD.
Video Based Experiment to Determine Focal Length of a Positive Lens in Physics Learning
Authors: Raida  , Iswanto B H , Sugihartono I
Published: October 2021

During the COVID-19 pandemic, conducting experiments in the lab has become constrained due to physical distancing protocols. Experiments activities are important to help students understand the concepts of physics, one of which is the optical learning of image formation on a positive lens. Video based experiment is one of the solutions that can be used as an alternative to do experiments activities in the laboratory due to the COVID-19 pandemic. This study aimed to design and develop a video based experiment to make students to determine focal length of a positive lens. This study used the R&D method with ADDIE development model reference (Analysis, Design, Development, Implementation, and Evaluation). According to the evaluation of material experts and media experts video based experiment covering aspects of content, material, language and presentation of media experts by 81% and material experts obtained by 84%, categorized as very high. Based on the results of the expert test, it can be concluded that the video based experiment is feasible to be used as an optical learning media for students in high school.
Module Electronic Sound and Light Wave Developed By Scientific Approach For Improving Science Literacy
Authors: Nenchi M , Budi A S , Rustana C E
Published: October 2021

The purpose of this study is to develop a physics learning media for Sound and Light wave physics learning in high school students. The research method used Analyze, Design, Development, Implementation and Evaluate (ADDIE) with one group pretest-posttest design method to improve scientific literacy. The research participants are students in grade eleven of high school students. The E-module was validated by experts and the results showed 84.59% for media expert, 83,49 % for material expert, and 79.75% for learning expert with very proper category. The instrument validation results for high school students were 84.27% with the very proper category. Based on the results of scientific literacy for high school students, the normalized gain score 0.79 with a effective category means E-module can improve students’ Science Literacy. So it can be concluded that, there is improving scientific literacy in students using the sound and light wave e-module based on a scientific approach.
The Video-Based STEM Experiment: An Observation of the Momentum of a Bouncing Ball
Authors: Sugihartono I , Sunaryo  , Rustana C , Luhukay J , Yaqin A A , Jalassuad K , Apriyansa A , Nugraha A
Published: October 2021

We have performed a video-based STEM experiment of a bouncing ball using a force plate logger sensor and Neulog application. Our objective was to observe the students understanding the relationship between impulse and momentum, examine this relation by bouncing a ball on a force plate logger sensor, and calculate impulse and change in momentum. All the data, such as raw data of force and time, video recorded, and the questions given to the 10th-grade senior high school students. Then, their answer will be analyzed to confirm the understanding of momentum during the learning process by video-based STEM experiments.
Enhancing Students’ Learning Activities Using Problem-Based Learning Model on Temperature and Heat Concept
Authors: Astra I M , Aminudin D , Henukh A
Published: October 2021

This study aimed to improve the learning activities of SMA Labschool Jakarta students in grade XI of MIPA 1 by applying the Problem-Based Learning model (PBL). The study was undertaken by employing a classroom action research method with 34 participating students on the topic of temperature and heat. The study was conducted in three cycles. The cycles are extended to; planning, action, observation, and reflection. The success indicator of the study was that students’ learning activities could reach > 75%. The data collection was through the use of an observation sheet and the implementation of the learning model. Based on the data analysis, the results indicated that students’ learning activities in the first cycle reached 41,7%. In cycle II, the score reached 61,76%. Finally, the score increased to 85,27% in cycle III. Therefore, it can be concluded that student learning activity increased. In other words, the results verified that Problem-Based Learning can significantly enhance students’ learning activities.
Review of Trends Project Based Learning (PjBL) Integrated STEM in Physics Learning
Authors: Solihin A , Wibowo F C , Astra I M
Published: October 2021

For physics teachers, how physics should be taught is an important question. This study, examines project based learning (PjBL) integrated in Science, Technology, Engineering and Mathematics (STEM). The aims of this study is to identify trends in PjBL integrated STEM in physics education. The method used is a bibliometric analysis method. 80 articles were collected from the literature of scholarly journals, both nationally and internationally through the Publish or Perish (PoP) application. The articles collected were analyzed using the VOSviewer application to obtain information. After analysis, information on the trend of PjBL integrated STEM was obtained by further analysis and by synthesizing it. The result of this study is that in recent years, Project Based Learning (PjBL) integrated STEM has become one of the trends and has become an option in implementing physics learning in schools. This can be seen from the many research, studies and discussions about PjBL integrated STEM in physics education. Based on the results of this literature study, several recommendations for future research were also obtained, namely so that PjBL integrated STEM can be better, it needs to be tried by adding various learning media in it, especially on-line learning media.
Perception of Novice Learners Using Blended Learning Approach During the Covid-19 Pandemic
Authors: Herliana F , Farhan A , Elisa  , Syukri M , Mahzum E
Published: October 2021

This study aims to determine the perceptions of students in physics education department, faculty of teacher training and education - Universitas Syiah Kuala who have just learned (novice learners) using the blended learning approach during the Covid-19 pandemic. This research is quantitative research with data collection using the form of questionnaires and interviews. The questionnaire to measure novice learners’ perceptions used a semantic differential scale. The indicators measured consist of 5 aspects, including: technology, classroom management, instructors, interaction, and instruction. The population of this study was all students of the Physics Education Department, faculty of teacher training and education - Universitas Syiah Kuala. Purposive sampling technique was used to select sample and obtained 250 novice learners of blended learning approach. The data analysis technique used is descriptive statistical analysis through the process of data collection, data reduction, data presentation, and conclusions. The results of this study indicate that the perception of novice learners of the blended learning approach is positive at 87.92%. However, there is still a negative perception on each indicator with a different percentage value. The Indicator of technological at 14.52%, class management at 11.32%, instructors at 10,99%, interaction at 11,70%, and instruction at 12.60%. The results of the research are expected to be of concern for lecturers in the physics education department to find out the obstacles of students in distance learning during the pandemic period and can be used as a reference for improving and developing distance learning using a blended learning approach to make it better.
Application of Online Science Practicum by Using Microsoft Teams and Learning Management System (LMS) During the Covid 19 Pandemic
Authors: Pertiwi W A , Sanjaya L A , Nadiyah  , Hasirah  , Haramen M , Budi A S , Zarvianti E , Puspa R W D , Sianipar L K , Qoiriyah W , Sitompul H
Published: October 2021

The research objective of this is to see how to apply science practicum online using Microsoft Teams and Learning Management System (LMS). The form of this research is classroom action research which aims to apply the online science practicum during the Covid 19 pandemic. Therefore, it is carried out using two cycles in the application of online science practicum. The subjects of this study were students of the seventh semester in the Natural Science practicum course. Through observation and evaluation, it is shown that in the cycle I the percentage of practicum implementation which includes aspects of preparation, process and data and practicum results is 87.5%, in cycle II it has increased to 92.5%. In the assessment aspect of the practicum report, the average practicum assessment obtained in the first cycle was 3.09 from the highest score of 4 and in the second cycle was 3.7, while the aspect of student knowledge about the use of the Microsoft team which was taken using google form was 93%. In the aspect of student knowledge about the use of Learning Management System (LMS) by 75% and aspects of student understanding in the implementation of online science practicum using Microsoft Teams by 75%.
Website of Physics Instructional (WoPI): Learning Physics from Home During COVID-19
Authors: Sanjaya L A , Nurkholis I , Iswanto B H , Wibowo F C , Fidhyallah N F , Puspa R W D , Ilmi N , Pertiwi W A , Sianipar L K , Rasmi D P
Published: October 2021

In recent years, the education system, especially in Indonesia, has begun to adapt to distance learning. Technology in the field of education has emerged. Therefore, this research has the aim of producing an E-module based on a STEM with website-assisted in learning Physics on rotational dynamics. This research was conducted by applying the research method of FODEM (Formative Development Method) and was limited to the development phase. The results of this study are E-module learning media assisted by a website that can be used through various electronic devices, with learning material based on the STEM (science, technology, engineering, and mathematics) approach that can help students understand physics subjects in rotational dynamics. Further research is needed regarding the validation of this STEM-based E-modules assisted with website.
TPACK Implementation in Physics Textbook: Practice Problem-Solving Skill in Newton’s Law of Motion for Senior High School Students
Authors: Bakri F , Kusuma KF , Permana AH
Published: October 2021

One of the skills needed in the 21st century is a problem-solving skill. This article describes the result of research on the implementation of TPACK in the physics textbook. The implementation of TPACK in the physics textbook is aimed to practice the problem-solving skill of senior high school students. The research method used is Research and Development with Dick & Carey model. Has been produced a physics textbook that integrates technological knowledge, pedagogical knowledge, and physics content knowledge in multiple representations with the stage to practice a problem-solving skill in Newton’s Law of Motion concept. The stages of problem-solving in the developed physics textbook are: (a) presents the problem at the beginning of the chapter; (b) asking several questions to focus the problem; (c) formulating hypotheses on the problem; (d) present the material in multiple representations based on pedagogical and technological studies, and (e) explain phenomena based on the physics concepts of being studied. The results of this study have been validated by experts, are physics material experts, learning experts, and textbook media experts. The validation result of the physics textbook was declared feasible to practice the problem-solving skill for senior high school students.
Brake Pad Characteristics of Natural Fiber Composites from Coconut Fibre and Wood Powder
Authors: Kholil A , Dwiyati S T , Wirawan R , M Elvin
Published: October 2021

The aim of the research is to develop brake pad of natural fibre composite from coconut fiber waste and wood powder. The characteristics of hardness, braking time and wear compared to the commercial brake pad had been studied. Test samples were produced by varying content of coconut fiber from 0 - 40% weight, wood powder content from 40% - 0 weight with 10% intervals. The percentage of polyester resin was made constant. The process of mixing ingredients started from filtering coconut fiber and wood powder using a filter with mesh size 40 μm. Then, the materials combined with certain composition into a container and stirred until evenly mixed. The composite poured into the mold was design appropriate the motorcycle disc brake pad dimensions. The test results of natural fiber composites on brake pads showed different characteristic values on hardness, wear, and braking time tests.
Design and Development a Wind Tunnel using the Honeycomb as a Wind Turbine Characterization Instrument
Authors: Nasbey H , Budi E
Published: October 2021

In this research, an open circuit wind tunnel system was developed with variations in the use of the honeycomb and not in the settling chamber. This system will be used as an instrument for testing the characteristics of wind turbines. Settling chamber, cylindrical with a diameter of 56 4 mm with a length of 150 mm. Contraction cone, a truncated cone with a large diameter of 564 mm and a small diameter of 460 mm and a height of 300 mm. The test section is cylindrical in shape with a diameter of 460 mm and a length of 500 mm. Diffuser, in the form of a truncated cone with a large diameter of 560 mm and a small diameter of 460 mm and a height of 400 mm. The use of honeycomb is aimed at reducing the value of the intensity of turbulence. The honeycomb consists of a PVC cylinder with a diameter of 8.5 mm and a length of 100 mm, placed in the settling chamber. The intensity of turbulence is defined as the ratio of the standard deviation to the mean value of the wind speed. The wind speed in the test section was measured using an anemometer at nine different measuring points around the center of a cross section of the test section. The nine-point wind speed was used to calculate the intensity of the turbulence. The turbulence intensity of the wind tunnel without honeycomb and with honeycomb in the settling chamber is approximately 0.864 and 0.178, respectively.
Feature Extraction of Tea Leaf Images using Dual-Tree Complex Wavelet Transform and Gray Level Co-occurrence Matrix
Authors: Iswanto B H , Alma  , Sugihartono I
Published: October 2021

Feature extraction is a very important part of machine learning to analyze and find relationships between objects of different categories. This paper aims to analyze the feature vectors of the tea leaf image produced by using a combination of dual-tree complex wavelet transform and gray level co-occurrence matrix techniques. The tea leaf image consists of four different categories, each representing different phases of tea growth and were acquired using a visible camera from eight different orientations. Feature extraction using Principle Component Analysis (PCA) shows that the texture features can identify a different category of the leaf images without being significantly affected by the difference in scale and orientation of the images.
Investigation the Vulnerability Potential of Landslide in Jayagiri Area Using the Geoelectric Method
Authors: Rusdiana R , Nurhasan  , Viridi S , Fitriani D
Published: October 2021

Landslides are the third-largest natural disaster and have resulted in many victims, both property and casualties. One area where landslides occurred with casualties and heavily damaged houses was in Jayagiri, Lembang, West Java, Indonesia.

One essential parameter in researching landslide-prone areas is the sliding area, where rocks or soil above the plane can move, resulting in landslides. Research on landslides continues to be developed from various fields of science. This study uses the Geoelectric method to determine and analyze the sliding area carried out in the Jayagiri area, Lembang. A reasonably significant resistivity value characterizes this field compared to the surrounding rocks. The measurement result on three lines shows that the study area is divided into two parts: the dominance of high resistivity and low resistivity. 2D inversion modeling shows that the slip plane has a resistivity value of 500 ohms.m at a depth between 9 m at the top of the slope and 13 meters at the bottom of the slope. The existence of a relatively shallow sliding field indicates a depth of water infiltration with a resistivity value of 10 Ohm.m, which is shallow enough so that it can be assumed that this area has the potential for landslides.
Permeability and Permittivity Measurements of Teflon in Millimeter Wave
Authors: Handoko E , Marpaung M A , Fahdiran R , Jalil Z , Alaydrus M
Published: October 2021

In order to expand a new millimeter wave absorbing material over the V-band frequency range, teflon were prepared with thickness of 1.4 mm, 1.5 mm, and 1.6 mm. The variation of electromagnetic variables (complex permeability µ=µ′–jµ″ and complex permittivity ε=ε′–jε″) properties were studied over the V-band frequency range with varying sample thickness. Both dielectric loss (ε″) and magnetic loss (µ″) were leading to strong fluctuations, whereas the dielectric constant (ε′) was found to decrease and magnetic permeability (µ′) increased in the frequency range of 50–67 GHz.
Pseudo-bosons and bi-coherent states out of

ℒ2(ℝ)
Authors: Bagarello Fabio
Published: October 2021

In this paper we continue our analysis on deformed canonical commutation relations and on their related pseudo-bosons and bi-coherent states. In particular, we show how to extend the original approach outside the Hilbert space

ℒ
2

(
ℝ
)

, leaving untouched the possibility of defining eigenstates of certain number-like operators, manifestly non self-adjoint, but opening to the possibility that these states are not square-integrable. We also extend this possibility to bi-coherent states, and we discuss in many details an example based on a couple of superpotentials first introduced in [30]. The results deduced here belong to the same distributional approach to pseudo-bosons first proposed in [29].
Ermakov-Pinney equation for time-varying mass systems
Authors: Bagchi Bijan , Vinod Achal
Published: October 2021

We extend Fring-Tenney approach of constructing invariants of constant mass time-dependent system to the case of a time-dependent mass particle. From a coupled set of equations described in terms of guiding parameter functions, we track down a modified Ermakov-Pinney equation involving a time-dependent mass function. As a concrete example we focus on an exponential choice of the mass function.
Efficient identification of node failure and recovery through end to end Probing techniques
Authors: Nikhil Chitturi Sai , Bollarapu Manjula Josephine , Neeraj Kaja Sai Sree , Kumar Alaparthi Praveen , Sai Raghuveer Manchikalapudi Jaya Sesha
Published: October 2021

Identification of Node failure detection and a localization is a very important challenge in a network community to get a quick recovery and avoid useless traffic in network. But it is very difficult to check the failure nodes or locations because of the large number of Screw ups in dense network. As finding the main source for failure of network is always challenging our proposed work will achieve that, it identifies the node failure by using probing measurement of binary state to end to end paths. Apart from identifying the network failure, it also quantifies the total failure nodes and the ip address or vicinity of failure nodes, Identification of node failure is done by monitoring nodes which are deployed in the netwok. Our Proposed word is divided majorly in two phases one is identifying the node failures by using Probing Packets and other is finding of the failure and its recovery.
Ant Colony Optimization Algorithm GPS Clustering Approach
Authors: Grace Mercy M. , Kamala Kumari A. , Bhujangarao A. , Nooka Raju V.
Published: October 2021

The geometry of the GPS satellite recipient (s), which reflects the recipient (s) of the satellites, has a major influence on the total positioning precision. The more precise the position, the stronger the geometry of the satellite. This article provides the geometry of satellite clustering for the selection of suitable satellite navigation subsets. This technique is based on the GDOP (Geometric Precision Dilution) satellite factor cluster with the Ant Colony Optimization (ACO) algorithm that has been created by simulating real and artificial ways to locate the quickest route between nesting resources and food. Pheromones are utilised in the suggested technique to assess the iterative outcome of single colonies. The ACO method can measure all subsets of satellites while reducing computer load by eliminating the need for a matrix inversion. Based on the simulation results, the GPS GDOP clustering technique is more efficient at achieving its optimum value.
Runoff volume prediction in the megadrigadda reservoir catchment due to past land use/land cover trends-a case study
Authors: Shiva Kumar P , Venkata Rao G , Raghava Rao Eswara Veera , Kannamu Naidu CH
Published: October 2021

One major source of water on the Earth is Surface water resources such as Rivers, Rain water sewers, Streams etc. With the rapid change in the mode of usage of land for various purposes like residential, agricultural, industrial, water storage basins, the volume of Surface runoff due to Rain & melting of Snow changes. Estimating such quantities of runoff is essential for proper managing of Water resources over the Earth surface. Runoff estimation of each Mini Water has been done by SCS-CN Curve number method. The required data for this method include Land Use/Land Cover trends of past years, Hydrological Soil Groups, Rainfall trends and AMC Type. Based on the analysis a considerable change in the Groundwater Recharge in the study area is found due to the variations in the Built-up & vegetative cover features ultimately resulting in increasing Surface Runoff there by excess inflow may enter into the Megadrigadda reservoir resulting in Flash floods during monsoons. In the coming years there are chances of the Dam being breached thereby affecting the Visakhapatnam Airport area in its Downstream.