bluuebunny/crossref_metadata_2025 huggingface dataset:
High-sensitivity detection of Concanavalin A using MoS2-based field effect transistor biosensor
Authors: Ma Mingyang , Chao Lemeng , Zhao Yuhang , Ding Jiafeng , Huang Zhongchao , Long Mengqiu , Wang Fuliang , Jiang Jie , Liu Zhengchun
Published: March 2021

The specific interaction between sugar and lectin plays a key role in various human diseases and projects remarkable significance to the development of a lectin biosensor for diagnosis and drug discovery. An inorganic nano MoS2 field-effect transistor (FET)-based D-Mannose biosensor was developed in this paper using a simple assembly process. First, gold nanoparticles were functionalized on the surface of MoS2. Then, the β-mercaptoethylamine was self-assembled on the gold surface via Au–S bonds to derivatize amino groups. Finally, the probe molecules D-Mannose for biological protein were immobilized on the FET via the Schiff base reaction. Results from scanning electron microscope and x-ray photoelectron spectroscopy analysis confirmed the entire assembly procedure and the feasible interaction of the FET sensor with Concanavalin A (ConA). The fabricated FET biosensors can reliably detect the target ConA with a detection limit below 105 nm. The current study shows the potential of MoS2 FET biosensors for ConA specific detection and clarifies the design of biosensors for the early diagnosis of glycomics and drug screening in medicine.
Pentamode metamaterials with ultra-low-frequency single-mode band gap based on constituent materials
Authors: Huang Yan , Zhang Xiaozhe
Published: March 2021

An effective method for realizing ultra-low-frequency single-mode band gap in pentamode metamaterials is proposed based on constituent materials. Results show that the decreasing ratio E/ρ (stiffness/mass density) of constituent material can significantly lower the frequency range of single-mode band gap. By merely replacing the constituent material from Al to rubber, the center frequency f
c of single-mode band gap can be reduced nearly 600 times (from 3621 Hz to 6.5 Hz), while the normalized bandwidth Δf/f
c and the ratio of bulk modulus B to shear modulus G of pentamode structure keep substantially stable. The nonlinear fitting demonstrates that the relation between f
c and E/ρ satisfies the logarithmic function. The two-component pentamode structure is designed to further explore the ultra-low-frequency single-mode band gap. The effects of thick-end diameter D of double-cone, diameter D
0 and material type of additional sphere, on single-mode band gap of two-component system are analyzed. This work is attractive for several ∼Hz acoustic/elastic wave regulations using pentamode metamaterials.
C

n
-symmetric Chern insulators
Authors: Han Ying , He Ai-Lei
Published: March 2021

Chern insulators (CIs) have attracted great interests for the realization of quantum Hall states without external magnetic field. Recently, CIs have been studied on various curved lattices, such as the cone-like lattices and the fullerenes. However, few works were reported how to identify curved-CIs and explore their topological phase transitions (TPTs). In this paper, we systemically investigate the curved-CIs with arbitrary n-fold rotational symmetry on cone-like and saddle-like lattices (also dubbed as C

n
-symmetric CIs), by ‘cutting and gluing’ unit sectors with a disk geometry. These C

n
-symmetric CIs can be identified based on the chiral edge states, the real-space Chern number and the quantized conductance. Here, we propose two ways to calculate the real-space Chern number, the Kitaev’s formula and the local Chern marker. Furthermore, the TPTs of curved CIs are explored by tuning staggered flux and on-site mass.
Radiation risks of lymphoma and multiple myeloma incidence in the updated NRRW-3 cohort in the UK: 1955–2011
Authors: Hunter Nezahat , Haylock Richard
Published: March 2021

The effect of external radiation on lymphoma, including non-Hodgkin lymphoma (NHL), Hodgkin lymphoma (HL) and multiple myeloma (MM) incidence was evaluated in the National Registry for Radiation Workers based upon the third analysis cohort but with an additional 10 years of follow-up. The study includes 172 452 workers, of whom (90%) were men with 5.25 million person-years of follow-up from 1955 through to the end of 2011. A total of 711 cases of NHL, 113 cases of HL and 279 cases of MM were registered. Poisson regression was used to estimate the excess relative risk per unit of cumulative exposure to ionising radiation. A statistically significant association was found between radiation dose and the incidence of NHL and MM. There was no evidence of radiation associated excess risk for HL. The reported associations are based on a very small proportion of exposed workers, in particular among workers with cumulative doses above 0.5 Sv so should be treated with caution, further investigations are necessary to confirm our results.
Standardization of histogram- and gray-level co-occurrence matrices-based radiomics in the presence of blur and noise
Authors: Gang Grace J , Deshpande Radhika , Stayman J Webster
Published: March 2021

Radiomics have been extensively investigated as quantitative biomarkers that can enhance the utility of imaging studies and aid the clinical decision making process. A major challenge to the clinical translation of radiomics is their variability as a result of different imaging and reconstruction protocols. In this work, we present a novel radiomics standardization framework capable of modeling and recovering the underlying radiomic feature in images that have been corrupted by the effects of spatial resolution and noise. We focus on two classes of radiomics based on pixel value distributions—i.e. histograms and gray-level co-occurrence matrices (GLCMs). We developed a model that predicts these distributions in the presence of system blur and noise, and used that model to invert these physical effects and recover the underlying distributions. Specifically, the effect of blur on histogram and GLCM is highly image-dependent, while additive noise convolves the histogram/GLCM of the noiseless image with those of the noise. The recovery method therefore consists of two deconvolution operations: the first in the image domain to remove the effect of system blur, the second in the histogram/GLCM domain to remove the effect of noise. The performance of the proposed recovery strategy was investigated using a set of texture phantoms and an emulated computed tomography imaging chain with a range of realistic blur and noise levels. The proposed method was able to obtain histogram and GLCM estimates that closely resemble the ground truth. The method performed well across imaging conditions and significantly lowered the variability associated with different imaging protocols. This improvement also translated to better classification accuracy, where recovered radiomic values result in greater separation of radiomic clusters for two different texture phantoms as compared to values derived from the original blurred and noisy images. In summary, the novel radiomics standardization framework demonstrates high potential for mitigating radiomic variability as a result of the imaging system and can potentially be integrated as a preprocessing step towards more robust and reproducible radiomic models.
Emergent mesoscopic quantum vortex and Planckian dissipation in the strange metal phase
Authors: Li Rong , She Zhen-Su
Published: March 2021

A major puzzle of condensed-matter physics is the physics behind the linear-in-temperature law of resistivity in many exotic metallic systems, including cuprates, pnictides, and heavy fermions. In this work, we propose, based on a symmetry-breaking analysis, that the strange metal phase is a novel emergent mesoscopic quantum state, beyond Landau’s quasiparticle excitation, which is composed of fluctuating vortices. The model predicts, in a straightforward way, the local magnetic field with a correlation time determined by the Coulomb potential, validated by observations of dynamic muon spin relaxation rates in both 3d cuprates and 5d iridate without fitting parameter. Furthermore, the model resolves the underlying quantum mechanism of the Planckian dissipation in terms of carrier scattering by fluctuating vortex, which predicts a scattering rate proportional to the vortex density, thus deriving both linear-in temperature and linear-in field laws, with a universal scattering coefficient validated by data of several dozens of samples for cuprates and iron pnictides. These findings offer a new phenomenology for non-Fermi liquid in strongly correlated materials.
Persistent currents in Bose–Bose mixtures after an interspecies interaction quench
Authors: Spehner D , Morales-Molina L , Reyes S A
Published: March 2021

We study the persistent currents and interspecies entanglement generation in a Bose–Bose mixture formed by two atomic gases (hereafter labeled by the letters A and B) trapped in a one-dimensional ring lattice potential with an artificial gauge field after a sudden quench from zero to strong interactions between the two gases. Assuming that the strength of these interactions is much larger than the single species energies and that the gas A is initially in the Mott-insulator regime, we show that the current of the gas B is reduced with respect to its value prior the interaction quench. Averaging fast oscillations out, the relative decrease of this current is independent of the initial visibility and Peierls phase of the gas B and behaves quadratically with the visibility of the gas A. The second Rényi entropy of the reduced state measuring the amount of entanglement between the two gases is found to scale linearly with the number of sites and to be proportional to the relative decrease of the current.
A numerical study of the entropy generation and heat transfer rate of airflow around a NACA 0015 airfoil subjected to an external magnetic field
Authors: Saffarzadeh Hamed , Djavareshkian Mohammad Hassan
Published: March 2021

In the present study, the thermal Lattice Boltzmann Technique is combined with the Ghost Fluid method to simulate the flow and heat transfer rate around a NACA 0015 airfoil in the presence of an external magnetic field source. It is tried to investigate the mutual effects of the Hartmann and Reynolds numbers as well as the magnetic field angle and the attack angle of the airfoil on the flow and heat transfer characteristics. Besides, the total entropy generation rate of the system was studied through its main components, i.e. entropy generation rate due to friction, heat transfer, and Magneto Hydrodynamics. Therefore, the tests were carried out for various Re and Ha numbers, plus different magnetic field angles and airfoil attack angles, and their influence on the active parameters which are Cd, Cl, and Nu, along with the entropy generation rate of the system, were recorded. The results revealed that with an increment of the Re number the Cd and Cl graphs drop, but the Nu value raises. Also, the total entropy generation rate of the system is at its maximum around γ = 60.
Terahertz flat-top broadband defect modes generated in periodically undulated waveguides
Authors: Zhang Kun , Fan Ya-Xian , Xu Lan-Lan , Liu Ting , Liu Huan , Tao Zhi-Yong
Published: March 2021

We propose a tunable flat-top broadband defect mode in the terahertz (THz) frequency range by inserting multiple defects into a periodic waveguide with undulated tube walls. When introducing a defect into periodic structures, we can achieve a defect mode with a very sharp transmission peak in the forbidden band due to the local resonance effect. Here, in the proposed multi-defect structure, we find a broadband defect mode with a bandwidth of 38.3 GHz appearing in the transmission spectrum, which is over 21 times that of the traditional defect mode. The simulations reveal that the broadband defect mode is caused by the competition between Bragg scattering and local resonances in multiple defect mode coupling. The bandwidth and center frequency of this broadband defect mode can be manipulated by altering the number and size of defects, which could be applied in various THz systems as functional devices.
Minimum variance estimation of statistical anisotropy via galaxy survey
Authors: Shiraishi Maresuke , Okumura Teppei , Akitsu Kazuyuki
Published: March 2021

We consider the benefits of measuring cosmic statistical anisotropy from redshift-space correlators of the galaxy number density fluctuation and the peculiar velocity field without adopting the plane-parallel (PP) approximation. Since the correlators are decomposed using the general tripolar spherical harmonic (TripoSH) basis, we can deal with wide-angle contributions untreatable by the PP approximation, and at the same time, target anisotropic signatures can be cleanly extracted. We, for the first time, compute the covariance of the TripoSH decomposition coefficient and the Fisher matrix to forecast the detectability of statistical anisotropy. The resultant expression of the covariance is free from nontrivial mixings between each multipole moment caused by the PP approximation and hence the detectability is fully optimized. Compared with the analysis under the PP approximation, the superiority in detectability is always confirmed, and it is highlighted, especially in the cases that the shot noise level is large and that target statistical anisotropy has a blue-tilted shape in Fourier space. The application of the TripoSH-based analysis to forthcoming all-sky survey data could result in constraints on anisotropy comparable to or tighter than the current cosmic microwave background ones.
Resonant sub-GeV Dirac dark matter
Authors: Bernreuther Elias , Heeba Saniya , Kahlhoefer Felix
Published: March 2021

We study the phenomenology and detection prospects of a sub-GeV Dirac dark matter candidate with resonantly enhanced annihilations via a dark photon mediator. The model evades cosmological constraints on light thermal particles in the early universe while simultaneously being in reach of current and upcoming terrestrial experiments. We conduct a global analysis of the parameter space, considering bounds from accelerator and direct detection experiments, as well as those arising from Big Bang Nucleosynthesis, the Cosmic Microwave Background and dark matter self-interactions. We also extend our discussion to the case of a dark matter subcomponent. We find that large regions of parameter space remain viable even for the case of a moderate resonant enhancement, and demonstrate the complementarity of different experimental strategies for further exploring this scenario.
Generating rotating spacetime in Ricci-based gravity: naked singularity as a black hole mimicker
Authors: Shao Wei-Hsiang , Chen Che-Yu , Chen Pisin
Published: March 2021

Motivated by the lack of rotating solutions sourced by matter in General Relativity as well as in modified gravity theories, we extend a recently discovered exact rotating solution of the minimal Einstein-scalar theory to its counterpart in Eddington-inspired Born-Infeld gravity coupled to a Born-Infeld scalar field.

This is accomplished with the implementation of a well-developed mapping between solutions of Ricci-Based Palatini theories of gravity and General Relativity.

The new solution is parametrized by the scalar charge and the Born-Infeld coupling constant apart from the mass and spin of the compact object.

Compared to the spacetime prior to the mapping, we find that the high-energy modifications at the Born-Infeld scale are able to suppress but not remove the curvature divergence of the original naked null singularity.

Depending on the sign of the Born-Infeld coupling constant, these modifications may even give rise to an additional timelike singularity exterior to the null one.

In spite of that, both of the naked singularities before and after the mapping are capable of casting shadows, and as a consequence of the mapping relation, their shadows turn out to be identical as seen by a distant observer on the equatorial plane.

Even though the scalar field induces a peculiar oblateness to the appearance of the shadow with its left and right endpoints held fixed, the closedness condition for the shadow contour sets a small upper bound on the absolute value of the scalar charge, which leads to observational features of the shadow closely resembling those of a Kerr black hole.
Searching for extremal spots
in Planck lensing maps
Authors: Jakubec Clemens , Sullivan Raelyn M. , Scott Douglas
Published: March 2021

A great deal of attention has been given to the so-called Cold Spot in maps of the cosmic microwave background (CMB) temperature.
We present a similar analysis, searching for extremal spots in the CMB lensing convergence and lensing potential maps from the Planck 2018 data release.
We perform a multi-scale and multi-filter analysis using the first three members of the Mexican-hat wavelet family to search for extremal features of different shapes and sizes. Although an initial analysis appears to show the existence of some extremal spots at scales below about 5, we conclude, after marginalising over all scales and filters, that no significant features are detected in the lensing maps. We conclude that in terms of maxima and minima of various sizes, the lensing data have similar statistical properties to Gaussian simulations.
The impact of new d(p,γ)3 rates on Big Bang Nucleosynthesis
Authors: Yeh Tsung-Han , Olive Keith A. , Fields Brian D.
Published: March 2021

We consider the effect on Big Bang Nucleosynthesis (BBN) of new measurements of the
d(p,γ)3 cross section by the LUNA Collaboration. These have an important effect on the primordial abundance of D/H which is also sensitive to the baryon density at the time of BBN.
We have re-evaluated the thermal rate for this reaction, using
a world average of cross section data, which we describe with
model-independent polynomials; our results are in good agreement with a similar
analysis by LUNA.

We then perform a full likelihood analysis
combining BBN and Planck cosmic microwave background (CMB) likelihood chains
using the new rate combined with previous measurements and compare with the results using previous rates. Concordance between BBN and CMB measurements of the anisotropy spectrum using the old rates was excellent. The predicted deuterium abundance at the Planck value of the baryon density was (D/H)BBN+CMB
old = (2.57 ± 0.13) × 10−5 which can be compared with the value determined from quasar absorption systems (D/H)obs = (2.55 ± 0.03) × 10−5. Using the new rates we find (D/H)BBN+CMB = (2.51 ± 0.11) × 10−5.

We thus find consistency among BBN theory, deuterium and 4 observations, and the CMB, when using reaction rates fit in our data-driven approach. We also find that the new reaction data tightens the constraints on the number of relativistic degrees of freedom during BBN, giving the effective number of light neutrino species Nν = 2.880 ± 0.144 in good agreement with the Standard Model of particle physics.

Finally, we note that the observed deuterium abundance continues to be more precise than the BBN+CMB prediction, whose error budget is now
dominated by d(d,n)3 and d(d,p)3 H.
More broadly, it is clear that the details of
the treatment of nuclear reactions and their uncertainty have become critical for BBN.
Effects of post-annealing on crystalline and transport properties of Bi2Te3 thin films*
Authors: Guo Qi-Xun , Ren Zhong-Xu , Huang Yi-Ya , Zheng Zhi-Chao , Wang Xue-Min , He Wei , Zhu Zhen-Dong , Teng Jiao
Published: March 2021

A well-established method is highly desirable for growing topological insulator thin films with low carrier density on a wafer-level scale. Here, we present a simple, scalable method based on magnetron sputtering to obtain high-quality Bi2Te3 films with the carrier density down to 4.0 × 1013 cm−2. In contrast to the most-used method of high substrate temperature growth, we firstly sputtered Bi2Te3 thin films at room temperature and then applied post-annealing. It enables the growth of highly-oriented Bi2Te3 thin films with larger grain size and smoother interface. The results of electrical transport show that it has a lower carrier density as well as a larger coherent length (∼228 nm, 2 K). Our studies pave the way toward large-scale, cost-effective production of Bi2Te3 thin films to be integrated with other materials in wafer-level scale for electronic and spintronic applications.
Preparation of a two-state mixture of ultracold fermionic atoms with balanced population subject to the unstable magnetic field*
Authors: Li Donghao , Huang Lianghui , Bian Guoqi , Miao Jie , Chen Liangchao , Meng Zengming , Han Wei , Wang Pengjun
Published: March 2021

We report a novel method to prepare a mixture of 40K Fermi gas having an equal population of the two ground magnetic spin states confined in an optical dipole trap, in the presence of an noisy quantization (magnetic) field. We realize the equal population mixture by applying a series of RF pulses. We observe the dependence of the population distribution between two spin states on the number of the applied RF pulses and find that the decoherence effects leading to the population fluctuations are overcome by the high number of RF pules. Our demonstrated technique can be potentially used in the precision measurement experiments with ultracold gases in noisy environments.
Towards real-life EEG applications: novel superporous hydrogel-based semi-dry EEG electrodes enabling automatically ‘charge–discharge’ electrolyte
Authors: Li Guangli , Wang Sizhe , Li Mingzhe , Duan Yanwen Y
Published: March 2021

Objective. A novel polyacrylamide/polyvinyl alcohol superporous hydrogel (PAAm/PVA SPH)-based semi-dry electrode was constructed for capturing electroencephalogram (EEG) signals at the hairy scalp, showing automatically ‘charge–discharge’ electrolyte concept in EEG electrode development. Approach. In this regard, PAAm/PVA SPH was polymerized in-situ in the hollow electrode cavity by freezing polymerization, which acted as a dynamic reservoir of electrolyte fluid. The SPH can be completely ‘charged’ with electrolyte fluid, such as saline, in just a few seconds and can be ‘discharged’ through a few tiny pillars into the scalp at a desirable rate. In this way, an ideal local skin hydration effect was achieved at electrode–skin contact sites, facilitating the bioelectrical signal pathway and significantly reducing electrode–skin impedance. Moreover, the electrode interface effectively avoids short circuit and inconvenient issues. Main results. The results show that the semi-dry electrode displayed low and stable contact impedance, showing non-polarization properties with low off-set potential and negligible potential drift. The average temporal cross-correlation coefficient between the semi-dry and conventional wet electrodes was 0.941. Frequency spectra also showed almost identical responses with anticipated neural electrophysiology responses. Significance. Considering prominent advantages such as a rapid setup, robust signal, and user-friendliness, the new concept of semi-dry electrodes shows excellent potential in emerging real-life EEG applications.
Poor man’s scaling:
XYZ
Coqblin–Schrieffer model revisited
Authors: Kogan Eugene , Shi Zheng
Published: March 2021

We derive the third-order poor man’s scaling equation for a generic Hamiltonian describing a quantum impurity embedded into an itinerant electron gas. We show that the XYZ Coqblin–Schrieffer model introduced by one of us earlier is algebraically renormalizable in the sense that the form of the Hamiltonian is preserved along the scaling trajectory, write down the scaling equations for the model, and analyze the renormalization group flows in the cases of both constant and pseudogap densities of states.
Tuning Ginzburg–Landau theory to quantitatively study thin ferromagnetic materials
Authors: Guruciaga Pamela C , Caballero Nirvana , Jeudy Vincent , Curiale Javier , Bustingorry Sebastian
Published: March 2021

Along with experiments, numerical simulations are key to gaining insight into the underlying mechanisms governing domain wall motion in thin ferromagnetic systems. However, a direct comparison between numerical simulation of model systems and experimental results still represents a great challenge. Here, we present a tuned Ginzburg–Landau model to quantitatively study the dynamics of domain walls in quasi two-dimensional ferromagnetic systems with perpendicular magnetic anisotropy. This model incorporates material and experimental parameters and the micromagnetic prescription for thermal fluctuations, allowing us to perform material-specific simulations and at the same time recover universal features. We show that our model quantitatively reproduces previous experimental velocity-field data in the archetypal perpendicular magnetic anisotropy Pt/Co/Pt ultra-thin films in the three dynamical regimes of domain wall motion (creep, depinning and flow). In addition, we present a statistical analysis of the domain wall width parameter, showing that our model can provide detailed nano-scale information while retaining the complex behavior of a statistical disordered model.
Correlation between mathematical creative thinking ability and mathematical creative thinking disposition in geometry
Authors: Yanty Putri Nasution Eline , Yulia Putri , Seprina Anggraini Reri , Putri Rahmi , Sari Maila
Published: March 2021

Mathematics educators commonly believe that an open-ended approach could facilitate students to build their creative thinking ability and its disposition, especially in geometry. This research belongs to a quasi-experiment that used a non-equivalent control group design. The purpose of this research was to analyze the correlation between creative thinking ability and creative thinking disposition through an open-ended learning approach toward area and volume of flat geometrical objects problems. Two classes are selected as the sample, they are the control group and experiment group. The open-ended approach was used in the experiment group then direct instruction in the control group. The population is all of the eighth-grade students at one of the junior high school in Bandung, West Java, Indonesia. This study used to test and non-test as the research instruments. The test instrument was a creative thinking ability test while the non-test instrument was a questionnaire. These instruments were given after the learning process then analyzed by using Bivariate Correlation through SPSS. According to the analysis results, the finding is: the correlation coefficient between creative thinking ability and creative thinking disposition is at the middle level. The conclusion is there is a significant correlation between students’ creative thinking ability and students’ creative thinking disposition.
Application of the CGVRP model and the 0-1 linear programming determines the RASKIN (subsidized rice) distribution route
Authors: Hermanto Koko , Ruskartina Eki , Gunawan
Published: March 2021

Distribution is one of the important aspects to run a business or enterprise. BULOG is a state-own enterprise that operates in the food security sector. One of its services is to distribute RASKIN (subsidized rice) to all district in Indonesia. Sumbawa is one of the big district in Indonesia has a BULOG Regional sub-division to distr So far, the distribution of Raskin carried out by BULOG in the district of Sumbawa still relies on the experience of drivers in distributing RASKIN to destination villages and the application of the heuristic method has never been applied to optimize distribution routes, considering that a large number of distribution areas creates many combinations of distribution channels. This study aims to propose the optimal distribution route for RASKIN for BULOG in Sumbawa district, Alas warehouse so that the distribution time and costs can be more optimal. In this study, this problem was solved using the Cluster General Vehicle Routing Problem (CGVRP) model and the 0-1 linear programming. The result shows that only 3 of 4 vehicles can be used to distribute RASKIN, whereas previously, BULOG use 4 vehicles. The total route of the three vehicles is 206.52 miles.
Strong edge antimagic total labeling on multistar
Authors: Arif Budi Prasetyo Dominikus
Published: March 2021

Strong edge antimagic total labelling of a simple graph G(V,E) is graph labelling which the vertex labels are consecutive integers from 1 to |V| such that, the weight of edges, i.e. the total label of the vertices incident to the edge, will form an ascending arithmetic sequence. This article discusses this kind of vertex labelling on multistar graphs. A multistar graph is an unconnected combination of star graphs. The study is a literature study with a mathematical proof. The results of the study is that multistar graphs have a strong edge antimagic total labelling. Furthermore, the labelling can be done on an unconnected combination of m star graphs and the difference of the weight of the edges are 1 and 2 with initial term

a
=

5
m
n
+
3
m
+
4

2

and

a
=

4
m
n
+
3
m
+
5

2

, respectively.
Critical thinking skills in mathematics
Authors: Aldila Afriansyah Ekasatya , Herman Tatang , Turmudi  , Afgani Dahlan Jarnawi
Published: March 2021

Teachers’ low mathematical critical thinking skills (MCTS) resulted in students’ low MCTS in the learning process. A teacher needs to have a good foundation of MCTS so that they can pass on their MCTS to their students. This study aims to improve the teaching and learning activities of teachers through prospective teachers and to find out whether there is an effect of the interaction between learning and Mathematical Prior Knowledge (MPK) of prospective teachers on the achievement of the MCTS. The solution offered in the learning process is Realistic Mathematics Education based on Emergent Modeling (RME-EM). The research method used is quantitative research methods. The research sample is prospective teachers at one of the private universities in West Java, as many as 51 people. The result of the research is that the achievement of the student teaching and learning activities of prospective teachers who get RME-EM learning is better than the achievement of the MCTS of prospective teachers who get conventional learning. On the influence of the interaction between learning (RME-EM and Conventional) and MPK (high, medium, and low) prospective teachers on the achievement of MCTS, it is found that there is an influence on the achievement of student teaching and learning activities based on learning and MPK, but there is no interaction between learning and MPK towards the achievement of prospective teachers. RME-EM learning can be implemented at various student levels and is quite successful in improving teaching and learning activities for prospective teachers. However, RME-EM learning activities are not sufficient to have a significant impact on the interaction between learning and MPK on prospective teachers. RME-EM can be a solution for teachers who want to improve their students’ MCTS in the classroom.
The development of students creativity through the implementation of guided inquiry method on sciences
Authors: Ajwar Muhamad , Faridah Fifi , Mariamah  , Ratnah  , Suratman  , Sulfahri  , Muniarti Puji
Published: March 2021

Creativity is an ability that is needed by students as prospective teachers, because students who have high creativity will be able to come up with ideas or concept, find and create something new, and be able to solve problems that arise quickly and accurately. The purpose of this study was to develop student creativity through the guided inquiry method in science. This research was an experimental study with one group post-test research design. The instrument used was the observation sheet and creativity questionnaire. Hypothesis testers use a statistical test (T-test) at a significant level of 5% with normality test prerequisites. The results obtained the T value of 1.747 with df 27. Sig (2-tailed) of 0.039 and T table of 1.703. Based on the calculation results, the calculated T value is greater T table (1,747> 1.703) and sig value 0.039 <0.05, which means that the guided inquiry method can develop student creativity in science.
PISA-LIKE: Uncertainty and data content in Statistics subject with futsal context
Authors: Mutia  , Effendi K N S , Sutirna
Published: March 2021

This research is a development research that will produce about a valid PISA-LIKE of uncertainty and data content with futsal context. The development model used in this study is the 4-D model (Define, Design, Develop, and Disseminate). The development phase discussed are a result of expert review and simulation. The review stage expert of this study were involved material experts, and language expert, as well as IX grade students in one of junior high school in Karawang at the simulation stage as the subjects. Da ta collection is done by documentation and interviews. Based on the result of data analysis, it can be concluded that this research has produced valid PISA-LIKE of uncertainty and data content with futsal context, it can be seen from the comments given by the validator and also the students at the simulation stage.
Measuring mathematical literacy of space and shape content as 21st century competency
Authors: Muliawanti Sari , Badu Kusuma Anggun
Published: March 2021

Mathematical literacy and self-regulated learning is one of the most important cognitive and affective skills to be developed in the class allowing students to participate in the 21st century. This research is qualitatively descriptive that aims to describe students’ mathematical literacy of space and shape content reviewed from self-regulated learning. The subject was VII G students of SMP Negeri 1 Purwokerto. The data was collecting by using questionnaire, test, and interview. Students were categorized into high, medium, and low self-regulated learning high. The results showed that high self-regulated learning students were capable to construct a concept based on context. The medium and low self-regulated learning students were not capable to fulfill any indicators.
Proportion problems: analyzing common errors
Authors: Humaira Salsabila Nilza , Lu’luilmaknun Ulfa , Wahyu Triutami Tabita , Hamdani Deni , Ayu Apsari Ratih
Published: March 2021

Proportion problems are problems that are often found in real life. For that, we need to be able to solve problems related to proportion. But some of us make the mistake of solving problems about proportion. The purpose of this research is to identify the types of errors made by junior high school students working on proportion problems. The types of errors students make are identified based on the types of test-taking errors by Nolting. There are three types of errors analyzed in this research, namely careless errors, concept errors, and test-taking errors. This research is qualitative descriptive research. Subjects’ research included 51 junior high school students, 27 male and 24 female. The research data were obtained from a test instrument of proportion topic consisting of 3 essay questions. The results of the research analysis showed that in problem 1 as many as 3.91% of students made first type error, 11.76% for second type, and 33.33% for third type. In problem 2 as many as 7.84% of students made first type error, 41.18% for second type, and 7.84% for third type. Whereas in problem 3 as many a s 0% of students made first type error, 21.57% for second type, and 62.75% for third type. Teachers need to design effective learning so that students’ errors can be decreased.
Students’ perception on learning mathematic during the time of covid 19
Authors: Marah Doly Nasution , Ahmad
Published: March 2021

Mathematics lessons were taken by SMP Muhammadiyah 57 Kota Medan students. However,. owever, the perception of learning is not yet known, therefore it is necessary to conduct research with the aim of describing students’ perceptions of learning mathematics at SMP Muhammadiyah 57 Kota Medan. his research is a descriptive study with a quantitative approach. The method used is a survey method. The research instrument used was a questionnaire with 20 statement items. Testing the research instrument was carried out on 34 students of class VIII G SMP Muhammadiyah 57 Kota Medan. The questionnaire was declared valid and reliable (r count = 0.841). The research subjects were students of class VIII D and C SMP Muhammadiyah 57 Kota Medan, totalling 67 respondents who were determined using the cluster sampling method by drawing randomly. The data analysis technique used descriptive statistical techniques in the form of descriptive and frequency distribution. The results showed that the perceptions of grade VIII students of SMP Muhammadiyah 57 Kota Medan towards learning mathematics were in the very positive category of 65.7%, the positive category 34.3%, and none (0%) of the respondents had less positive and negative perceptions. Based on the results of this study, the perceptions of grade VIII students towards learning mathematics at SMP Muhammadiyah 57 Kota Medan were mostly very positive
Teacher’s belief and mathematical knowledge contributing ICT literacy in an Indonesian context
Authors: Nugroho Yanuarto Wanda , Mistima Maat Siti , Husnin Hazrati
Published: March 2021

This paper covers the perception of four mathematics senior school teachers in the Banyumas region, Indonesia, on the factors of contributing to ICT literacy. Two factors of ICT literacy contribution were gained based on the result of a semi-structured qualitative interview. Those were internal factors and external factors. The internal factor is the teacher’s belief, which consist of basic skills, workload, motivation, and the teaching style pattern of the teachers. The external factors are reflected in the teacher’s knowledge factors, such as technological guidance knowledge, technological management knowledge, and technological integrity knowledge. Then, the result of this study indicates that the teacher’s workload and the proficiency of the teacher’s principles can be classified into basic knowledge in the curriculum. In contrast, assessment, teacher motivation, and teaching style patterns can be classified into the teacher’s awareness of understanding ICT in education. Moreover, In the context of technological management knowledge can be classified in organization and administration, technological guidance knowledge is obtained from professional teacher learning, and technological integrity knowledge can be included in integrating technology in pedagogy.
SketchUp-aided generative learning in solid geometry: Does it affected students’ spatial abilities?
Authors: Jaelani Anton
Published: March 2021

Spatial ability is one of the abilities that should be mastered by students because daily human life requires it. Learning geometry that does not match the characteristics of students causes low spatial abilities. The purpose of this study was to determine the achievement and improvement of students’ spatial abilities after they participated in SketchUp-aided generative learning. This research is quasi-experimental research to compare students who were receiving SketchUp-aided generative learning and direct learning. The research instrument was a test of spatial ability, and the subjects were students of class XII high school. The results showed that spatial ability increased after receiving SketchUp-Aided generative learning. The results of this study contribute to providing suggestions for teachers to apply SketchUp-aided generative learning.
The effect of group mentoring learning on student’s creativity in solving partial differential equations problems
Authors: Yulis Tyaningsih Ratna , Pramestie Wulandari Nourma , Junaidi  , Hamdani Deni , Putranto Sumbaji
Published: March 2021

The Group Mentoring Learning Model is a learning model that emphasizes group collaboration by using the methods of teaching one another, demonstrating, and modeling the newly acquired knowledge and skills. The core stages of the GML Model include orientation, discussion, comparing, mentoring, creating, and evaluation. The type of questions used in this study is Middle Ended, which is a problem with one solution and many solution strategies. The purpose of this study was to determine the effectiveness of the Group Mentoring Learning Model on student creativity in solving partial differential equation problems. Data collection techniques used in this study were observation, questionnaire, pretest, and posttest. The data obtained were then analyzed using paired t-sample tests. The subjects of this study were students of Mathematics Education at Universitas Mataram Semester VI Academic Year 2019/2020. The results of data analysis showed that (1) the percentage of the implementation of the GML model for all stages was 81.01% and it was categorized as quite good, (2) the positive response of students in the implementation of learning using GML with a total average of 2.95 and included in the fairly good category, (3)) the effectiveness of the GML model in increasing student creativity in solving partial differential equation problems with N-Gain value = 56.5031% which is categorized as quite effective, and (4) there are differences in the level of student creativity before and after applying learning with the Group Mentoring Learning Models with t count = -15,875 <-2,056 = t table. Based on the results of the study it was concluded that the application of the Group Mentoring Learning model was effective on student creativity in solving Partial Differentia l Equations problems.
Errors of completing mathematical problems on number pattern material
Authors: Eko Subekti Fitrianto , Zuhrotunnisa
Published: March 2021

Error analysis is needed to provide information about student weaknesses to correct mistakes. This study analyzes grade VIIIA students’ errors of MTs Negeri 3 Banjarnegara on number pattern material. The data obtained using a multiple-choice test accompanied by the student’s working steps. The data were analyzed using percentages and described qualitatively. The results showed that the errors of male students tended to be higher than that of female students. Male and female students in the number pattern material made conceptual, procedural, and error due to lack of thoroughness.
Design of Cryogenic CMOS LNAs for Space Communications
Authors: Mudavath Mahesh , Valasa Sresta , Saisrinithya Avunoori , Divya Amgothu Laxmi
Published: March 2021

This manuscript presents the 45nm CMOS Low Noise Amplifier (LNA) designed for cryogenic use in spaces. A revised approach has been adopted to classical LNA architecture. External discreet components were added to the LNA in such a way that the LNA S11 and S22 were under –10dB from 70K to 290K at 2.44GHz designated for spatial communications. The LNAs IIP3 performance was analyzed, in particular at cryogenic temperatures, and linearity improvements were demonstrated by using the proposed approach. Although the LNA was not specifically hardened by radiation, no degradation was observed in its performance. Results analysis present that LNA achieves input and output impedance matching’s of -24.024 and -23.131dB, NFs of 0.9dB, power gain of 26.7dB, P-1dB of -10.63dBm, IIP3 of -10.6dBm at 2.44GHz, respectively.
Deep learning assisted heart arrhythmia detection
Authors: Fernandes Johnathan , Chudgar Sarthak , Dharap Harshal , Poduval Aneesh
Published: March 2021

Heart arrhythmia, or irregular heart rhythm, is an extremely common heart affliction experienced by a large percent of the world’s population every day, mostly going unnoticed. However, if left unchecked for an extended period of time, it poses an inherent risk to human life. Advancements in technology have enabled us to leverage the awesome computational power of graphics processing units in parallel in order to derive solutions to real life medical issues, by analyzing tremendous amounts of data in a relatively short amount of time. Owing to their ability to parse huge amounts of data and quickly perform multiple complex computations in parallel, machine learning algorithms have repeatedly and consistently outperformed humans in tasks such as pattern recognition and data analysis. Through this research project, we seek to contribute to the medical field by implementing deep learning technology along with machine learning algorithms into a system which can detect heart arrhythmias from electrocardiogram (ECG) reports quickly and effectively.
Spam Detection and Spammer Behaviour Analysis in Twitter Using Content Based Filtering Approach
Authors: Mukunthan B. , Arunkrishna M.
Published: March 2021

Twitter is one of the most popular social media networks and therefore it is prone to misuse. One of the ways in which people misuse Twitter is by spamming. Spam becomes an issue once a communication medium especially one, which enables global communication and handle huge amount of online data. Since Twitter is popular among so many people, it makes it easy for spammers to thrive. Spammers are people who send unwanted messages to people to either advertise a product or lure the victims into clicking malicious links, which may affect their user systems. The main objective of these spammers is usually to make money from their victims. In the last years, several systems has-been made with the aim of determining whether a user is a spammer or not. However, these systems cannot filter each spam message and a different account can be created by a spammer and used to send other messages. This paper proposes a content-based approach, which can be used to filter spam tweets. The approach involves using tweets in machine learning and compression algorithms in order to filter the undesired tweets.
VLSI Implementation of Discrete Cosine Transform Approximation Recursive Algorithm
Authors: Deivakani M. , Kumar S.V. Sudheer , Kumar Naluguru Udaya , Raj E. Fantin Irudaya , Ramakrishna V.
Published: March 2021

In general, the approximation of Discrete Cosine Transform (DCT) is used to decrease computational complexity without impacting its efficiency in coding. Many of the latest algorithms used in DCT approximation functions have only a smaller DCT length transform of which some are non-orthogonal. For computing DCT orthogonal approximation, a general recursive algorithm is used here, and its length is obtained using DCT pairs of length N/2 of N addition cost in input pre-processing. The recursive sparse matrix has been decomposed by using the vector symmetry from the DCT basis in order to achieve the proposed approximation algorithm that is highly scalable to enforce the highest lengths software and hardware by using a current 8-point approximation to obtain a DCT approximation with two-length power, N>8.
Numerical Examination of Detectivity in Group-IV alloy based Infrared Photodetector
Authors: Pareek Prakash , Ranjan Ravi
Published: March 2021

In this work, a numerical exploration is carried out for detectivity in Tin incorporated group IV alloys based multiple quantum well infrared photodetector. An optimized theoretical model of the device is developed and explained along with appropriate justifications. Responsivity and dark current are used to attain detectivity after applying proper considerations. The calculated detectivity is then examined under deviation of some important parameters. The results depict an increment of detectivity with number of wells. Furthermore, the results also estimate a considerable detectivity in the range of 109 cm Hz1/2 W−1.