bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of carbon nanotubes on the mechanical properties of cast Al–Si–Cu alloys
Authors: Okayasu Mitsuhiro , Wu Shauha , Hasanah Indah Uswatun
Published: February 2022

To enhance the mechanical properties of cast Al–Si–Cu alloys (ADC12), 0.3% of carbon nanotubes (CNTs) was added. The cast ADC12–0.3%CNT samples were synthesised via heated mould continuous casting for the creation of fine grains, and the artificial aging process was conducted at 173°C for 13 h to obtain precipitation hardening. The reinforcement and refinement of eutectic Si and precipitates (Al2Cu and Mg2Si) were achieved by adding CNTs, which leads to a high tensile strength of about 450 MPa and a relatively high ductility of about 10%. The obtained tensile strength and 0.2% proof stress are more than twice as high as those of the conventional cast ADC12 alloy. The refinement of the microstructures could be due to the interruption of their growth caused by the CNTs.
Patients with Substance use Disorders Receiving Continued Care in Skilled Nursing Facilities following Hospitalization
Authors: Mitchell Shannon Gwin , Nordeck Courtney D. , Lertch Elizabeth , Ross Tyler E. , Welsh Christopher , Schwartz Robert P. , Gryczynski Jan
Published: February 2022

Background: As hospitals in the US face pressures to reduce lengths of stay, healthcare systems are increasingly utilizing skilled nursing facilities (SNFs) to continue treating patients stable enough to leave the hospital, but not to return home. Substance use disorder (SUD) can complicate care of patients transferred to SNFs. The objective of this paper is to understand SNF experiences for this population of patients with comorbid SUD transferred to SNFs and examine care experiences in these facilities. Methods: This secondary mixed-methods analysis focuses on SNF experiences from a clinical trial of patient navigation services for medically-hospitalized adults with comorbid opioid, cocaine, and/or alcohol use disorder. This study compared baseline assessments and medical record review for participants ( N = 400) with vs. without SNF transfer, and analyzed semi-structured qualitative interviews with a subsample of 15 participants purposively selected based on their transfer to a SNF. Results: Over 1 in 4 participants had a planned discharged to a SNF (26.8% sub-acute, 3.3% acute). Compared to participants with other types of discharge, participants discharged to a SNF had longer initial hospitalizations (4.9 vs. 11.8 days, p < 0.001), and were more likely to be White (38.6 vs. 50.8%; p = 0.02), female (38.9 vs. 52.5%; p = 0.01), have opioid use disorder (75.7 vs. 85.0%, p = 0.03), and be hospitalized for infection (43.6 vs. 58.3%; p = 0.007), and less likely to have worked prior to hospitalization (24.3 vs. 12.5%; p = 0.006). Qualitative narratives identified several themes from the SNF experience, including opioid analgesic dosing issues, challenges to the use of opioid agonist treatment of OUD, illicit opioid dealing/use, and limited access to addiction recovery support services during and following the SNF stay. Conclusions: SNFs are a common disposition for patients in need of subacute services following hospitalization but may be ill-equipped to properly manage patients in need of new or continuing SUD treatment.
Changes in the skin characteristics associated with dehydration and rehydration
Authors: Eda Nobuhiko , Nakamura Nobuhiro , Inai Yuto , Sun Ziyue , Sone Ryota , Watanabe Koichi , Akama Takao
Published: February 2022

The present study aimed to test the hypothesis that changes in the dermal tissue dielectric constant (TDC) and biomechanical properties of the skin would be correlated with the indicators related to dehydration. Ten healthy adult men were enrolled in three trials: no fluid intake (DEH), ad libitum fluid intake (AL‐HYD), and programmed fluid intake (P‐HYD) after exercise in a randomised crossover design. The participants performed a pedalling exercise at 60% heart rate reserve until 2% body mass loss. At 120 min after exercise, an incremental exercise test was carried out. Aerobic capacity, body composition, TDC, biomechanical properties of the skin (pliability, viscoelasticity, and total recovery), and indicators related to dehydration in the serum and urine were measured before and 120 min after exercise. Higher values of the pliability and viscoelasticity, and lower value of the total recovery on the hand were demonstrated in the P‐HYD trial compared to the DEH trial (all P < 0.05). Changes in the TDC were significantly correlated with changes in body mass, total body water, serum osmolarity, and hematocrit (all P < 0.05). Changes in the biomechanical properties of the hand were significantly correlated with changes in body mass, hematocrit, and urine specific gravity (all P < 0.05). The present study showed that the changes in skin characteristics correlated with the body water and dehydration‐associated indicators in the serum and urine, thus suggesting that skin characteristics may be useful in the assessment of dehydration.

Highlights

This study was the first to investigate the effect of dehydration and rehydration on the TDC and biomechanical properties of the skin upon instrumental measure, and not manual testing.

This study confirmed the decline in aerobic capacity by dehydration and immediate recovery with sufficient rehydration.

Changes in the TDC and the biomechanical properties of the skin correlated with the body water and dehydration‐associated indicators in the serum and urine.

Skin characteristics may be useful in the assessment of dehydration.
The core autophagy protein ATG9A controls dynamics of cell protrusions and directed migration
Authors: Campisi Daniele , Desrues Laurence , Dembélé Kléouforo-Paul , Mutel Alexandre , Parment Renaud , Gandolfo Pierrick , Castel Hélène , Morin Fabrice
Published: February 2022

Chemotactic migration is a fundamental cellular behavior relying on the coordinated flux of lipids and cargo proteins toward the leading edge. We found here that the core autophagy protein ATG9A plays a critical role in the chemotactic migration of several human cell lines, including highly invasive glioma cells. Depletion of ATG9A protein altered the formation of large and persistent filamentous actin (F-actin)–rich lamellipodia that normally drive directional migration. Using live-cell TIRF microscopy, we demonstrated that ATG9A-positive vesicles are targeted toward the migration front of polarized cells, where their exocytosis correlates with protrusive activity. Finally, we found that ATG9A was critical for efficient delivery of β1 integrin to the leading edge and normal adhesion dynamics. Collectively, our data uncover a new function for ATG9A protein and indicate that ATG9A-positive vesicles are mobilized during chemotactic stimulation to facilitate expansion of the lamellipodium and its anchorage to the extracellular matrix.
Cell migration orchestrates migrasome formation by shaping retraction fibers
Authors: Fan Changyuan , Shi Xuemeng , Zhao Kaikai , Wang Linbo , Shi Kun , Liu Yan-Jun , Li Hui , Ji Baohua , Jiu Yaming
Published: February 2022

Migrasomes are recently discovered vesicle-like structures on retraction fibers of migrating cells that have been linked with transfer of cellular contents, shedding of unwanted materials, and information integration. However, whether and how the cell migration paradigm regulates migrasome formation is not clear. Here, we report that there are significantly fewer migrasomes in turning cells compared with straight persistently migrating cells. The major insight underlying this observation is that as the cells elongate, their rear ends become narrower, subsequently resulting in fewer retraction fibers during impersistent migration. In addition to migration persistence, we reveal that migration speed positively corelates with migrasome formation, owing to the derived length of retraction fibers. Substantiating our hypothesis, genetically removing vimentin compromises cell migration speed and persistence and leads to fewer migrasomes. Together, our data explicate the critical roles of two cell migration patterns, persistence and speed, in the control of migrasome formation by regulating retraction fibers.
Instrumented Charpy tests on low- and high-energy specimens
Authors: Lucon E , Machado R R
Published: February 2022

Main text

This report describes a CIPM Key Comparison through the SIM/MWG-7 organization, concerning instrumented impact testing of low-energy (20 J) and high-energy (100 J) Charpy V-notch specimens.

In this Comparison, various instrumented and non-instrumented data were obtained from instrumented Charpy tests performed at the pilot (NIST) and participant (INMETRO) laboratories using the same instrumented Charpy striker and acquisition system.

The use of instrumented absorbed energy (Wt), rather than absorbed energy yielded by the impact machine encoder or dial gage (KV), guarantees traceability to the International System and offers the promise of reducing bias between NMIs and simplifying comparisons between certification systems.

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Final report on CCQM-K167: carbon isotope delta measurements of vanillin
Authors: Chartrand Michelle M G , Chubchenko Ian , Dunn Philip J H , Garrido Bruno Carius , Hai Lu , Liu Fong-Ha , Ogrinc Nives , Simsek Adnan , Fasciotti Maíra , Goenaga-Infante Heidi , Hill Sarah , Kolobova Anna , Malinovsky Dmitriy , Merrick Jeffrey P , Rego Eliane Cristina Pires do , Potočnik Doris , Monteiro Thays Vieira da Costa , Wollinger Wagner , Xiao Li , Toman Blaza , Mester Zoltan , Meija Juris
Published: February 2022

Main text

The CCQM Isotope Ratio Working Group (IRWG) determined that an additional key comparison of carbon isotope delta measurements was required to capture the progress of this field. Vials containing 0.25 mg of vanillin were prepared at NRC, and evaluated for bottle-to-bottle homogeneity prior to distribution to the eight participating institutes. Participants were able to choose any suitable method and reference materials for carbon isotope delta measurements, and report a carbon isotope delta value and the associated uncertainty, and analysis details. To determine the key comparison reference value (KCRV) and its associated uncertainty, the NRC in collaboration with the NIST, developed a multivariate Bayesian random laboratory effects model, which also incorporates the uncertainty due to bottle-to-bottle homogeneity and any correlations between the reported results that arise due to the use of common reference materials. The KCRV for this study was determined to be -25.833 ‰ relative to the VPDB, with associated uncertainty of 0.028 ‰, and expanded uncertainty of 0.056 ‰ (k=2). All the results reported by the participants in this study were considered equivalent to the KCRV.

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
ReflectSim: an open-source software for teaching optical light reflection of nanostructured materials
Authors: Keene Clayton , Robertson Mark , Sarkar Gautam , King Jessica , Qiang Zhe
Published: February 2022

Leveraging computational resources for modern physics education has become increasingly prevalent, especially catalyzed by the COVID-19 pandemic when distance learning is widely implemented. Herein, we report an open-source software for students and instructors to on-demand simulate optical reflection behaviors of one-dimensional photonic crystals (1D-PCs), a model system for understanding light–matter interactions relevant to materials science and optical physics. Specifically, our MATLAB application, ReflectSim, employs an adapted transfer matrix method simulation and can account for the effects of several critical material design parameters, including interfacial roughness and layer geometry, to determine the reflectance spectrum of user-defined 1D-PCs. By packing our codes into a graphical user interface, this software is simple to use and bypass the requirement of any coding experiences from users, which can be widely used as an education tool in high school/undergraduate classrooms and K-12 outreach activities. We believe that ReflectSim provides great potential for assisting students in understanding optical phenomenon in nanostructured layered materials and relevant scientific concepts through enabling more engaging learning experiences.
Improvement on the uniformity of deep reactive ion etch for electrically isolated silicon-based substrates
Authors: Hu Xiao , Zhen Zhihan , Sun Guotao , Wang Qingkang , Huang Qiyu
Published: February 2022

Substrate-free micro-electro-mechanical systems (MEMS) devices are becoming the hotspots for microsystems. The fabrication of substrate-free MEMS devices usually involves the release of backside silicon by the inductively coupled plasma deep reactive ion etch (ICP-DRIE) process. However, when using DRIE to etch electrically isolated samples, significant non-uniformity in the etch profile were often observed. Compared to grounded silicon samples, the electrically isolated counterparts after DRIE showed a faster etch rate at the edge and a slower one in the center. This phenomenon is believed to be caused by the interaction between the deflection of charge-bearing ions entering the aperture region and the accumulated charges on the sidewall during DRIE. Simulation results with ICP showed that the electric field and ion distribution can be affected in electrically isolated substrates. After the isolated samples were electrically grounded, the charge accumulation on the sidewall was reduced and 12% etch uniformity was obtained. This technique helps in the fabrication of substrate-free MEMS devices.
Amplitude-phase modulation metasurface hologram with inverse angular spectrum diffraction theory
Authors: Su Deer , Wang Xinwei , Shang Guanyu , Ding Xumin , Burokur Shah Nawaz , Liu Jian , Li Haoyu
Published: February 2022

Designed metasurfaces, composed of a two-dimensional array of meta-atoms, provide an alternative approach to achieving efficient electromagnetic wave manipulation. Metasurface holography is an emerging and promising imaging technology, with improved image quality and spatial resolution compared to traditional holography. Many devices are fabricated only by coding specific phase responses of the designed metasurfaces. However, the modulation of both the amplitude and phase responses of electromagnetic waves can significantly improve the quality of the holographic image. In this paper, we employ bi-layered split rings as meta-atoms, which can fully control the transmission amplitude and phase independently. Furthermore, we present an algorithm based on the inverse angular spectrum diffraction theory to obtain the amplitude and phase information for the shape and arrangement of the meta-atoms. The proof-of-concept experiments in the microwave regime demonstrate that the inverse angular spectrum diffraction theory shows better image quality than the conventional Gerchberg-Saxton algorithm, especially when the number of meta-atoms is the same or even slightly fewer. The proposed approach provides an innovative and effective method for hologram design and expands the route to versatile applications related to holographic technologies.
Nanomechanical design strategy for single-mode optomechanical measurement
Authors: La Gala Giada , P Mathew John , Neveu Pascal , Verhagen Ewold
Published: February 2022

The motion of a mechanical resonator is intrinsically decomposed over a collection of normal modes of vibration. When the resonator is used as a sensor, its multimode nature often deteriorates or limits its performance and sensitivity. This challenge is frequently encountered in state-of-the-art optomechanical sensing platforms. We present a mechanical design strategy that ensures that optomechanical measurements can retrieve information on a single mechanical degree of freedom, and implement it in a sliced photonic crystal nanobeam resonator. A spectral design approach is used to make mechanical symmetries robust against practical disorder. The effectiveness of the method is evaluated by deriving a relevant figure of merit for continuous and pulsed measurement application scenarios. The method can be employed in any mechanical design that presents unwanted spurious mechanical modes. In the nanobeam platform, we experimentally show an increase of the signal to noise ratio of the mode of interest over the first spurious mode by four orders of magnitudes.
Dielectric loading method for doubly resonant enhancement of third-harmonic generation from complementary split-ring resonators
Authors: Chen Hao , Qin Zhaofu , Hu Taozheng , Chen Zhuo , Zhan Peng , Wang Zhenlin
Published: February 2022

Nonlinear optical response could be greatly enhanced when metasurfaces support plasmonic resonances at both fundamental and harmonic wavelengths. However, it is still challenging to fulfill the doubly resonant condition. Here, we propose a dielectric-loading method, which simply coats a conformal thin dielectric layer onto the plasmonic metasurfaces, to introduce an additional degree of freedom and make the doubly resonant condition easily fulfilled. We demonstrate that by simultaneously tuning the thickness of the coated dielectric layer and the geometrical parameters of the gold complementary split-ring resonators (CSRRs), the doubly resonant enhancement of third harmonic generation (THG) could be achieved for any given fundamental wavelengths. We also experimentally verify this concept and show that the THG intensity in the dielectric-loaded CSRRs under the doubly resonant condition could be further increased about 3 times as compared with the case of the conventional CSRRs.
Laser-assisted synthesis of Au aerogel with high-index facets for ethanol oxidation
Authors: Zhu Jiayin , Zhang Ran , Zhu Liye , Liu Xuan , Zhu Tiying , Guo Ziang , Zhao Yan
Published: February 2022

Gold (Au) can be used as an ideal metal electrocatalyst for ethanol and glucose oxidation reactions due to its high performance-to-cost ratio. In this paper, the Au aerogel with high-index facets was synthesized by using the laser ablation in liquid technology, which can improve the electrocatalytic activity of Au. The as-prepared Au aerogel showed excellent mass activity and specific activity toward ethanol oxidation reaction, which are 4.6 times and 2.1 times higher than Au/C, respectively. The 3D porous nature and rich defect of the Au aerogel provide more active sites. In addition, the high-index facets with under-coordinated atoms enhance the adsorption of ethanol and glucose molecules, thus improving the intrinsic catalytic activity of Au aerogel. The effect of high-index facets has also been investigated by density functional theory calculations. Furthermore, the Au aerogels also show good electrocatalytic activity and stability toward glucose oxidation reaction. These results are conducive to promote the practical application of Au in electrocatalysis.
Computer-aided detection of pulmonary nodules based on convolutional neural networks: a review
Authors: Min Yuqin , Hu Liangyun , Wei Long , Nie Shengdong
Published: February 2022

Computer-aided detection (CADe) technology has been proven to increase the detection rate of pulmonary nodules that has important clinical significance for the early diagnosis of lung cancer. In this study, we systematically review the latest techniques in pulmonary nodule CADe based on deep learning models with convolutional neural networks in computed tomography images. First, the brief descriptions and popular architecture of convolutional neural networks are introduced. Second, several common public databases and evaluation metrics are briefly described. Third, state-of-the-art approaches with excellent performances are selected. Subsequently, we combine the clinical diagnostic process and the traditional four steps of pulmonary nodule CADe into two stages, namely, data preprocessing and image analysis. Further, the major optimizations of deep learning models and algorithms are highlighted according to the progressive evaluation effect of each method, and some clinical evidence is added. Finally, various methods are summarized and compared. The innovative or valuable contributions of each method are expected to guide future research directions. The analyzed results show that deep learning-based methods significantly transformed the detection of pulmonary nodules, and the design of these methods can be inspired by clinical imaging diagnostic procedures. Moreover, focusing on the image analysis stage will result in improved returns. In particular, optimal results can be achieved by optimizing the steps of candidate nodule generation and false positive reduction. End-to-end methods, with greater operating speeds and lower computational consumptions, are superior to other methods in CADe of pulmonary nodules.
Enhanced plasma generation in capacitively coupled plasma using a parallel inductor
Authors: Lim Yeong-Min , He You , Lee Jaewon , Kim Ju-Ho , Kim Kyung-Hyun , Chung Chin-Wook
Published: February 2022

Plasma generation efficiency in a capacitively coupled plasma (CCP) at high densities or high conductivity tends to be lower due to low plasma resistance. An inductor is installed to a powered electrode in parallel to improve plasma generation efficiency at higher density in the CCP. To reduce the power loss in a system, a parallel resonance is used between the capacitance of the CCP and the inductance of the parallel inductor. When parallel resonance occurs, the impedance of the chamber, including the plasma, increases. Therefore, the current flowing in the system is expected to decrease. At the resonance, the current in the system significantly decreases, and the voltages and currents at the powered electrode significantly increase. This phenomenon indicates that the system power loss is decreased, and the power absorbed by the plasma is increased. As a result, the ion density and the voltage at the powered electrode are increased up to 66% and 25% at the parallel resonance condition, respectively. To understand these increases, a circuit model for the plasma and the parallel inductor is suggested which shows good agreement with the experimental results. This method can be applied to the CCP for improving plasma generation.
Charged particle kinetics and gas heating in CO2 microwave plasma contraction: comparisons of simulations and experiments
Authors: Vialetto L , van de Steeg A W , Viegas P , Longo S , van Rooij G J , van de Sanden M C M , van Dijk J , Diomede P
Published: February 2022

This work investigates kinetics and transport of CO2 microwave plasmas through simulation results from a 1D radial fluid model and experiments. Simulation results are validated against spatially resolved measurements of neutral species mole fractions, gas temperature, electron number density and temperature obtained by means of Thomson and Raman scattering diagnostics, yielding good agreement. As such, the model is used to complement experiments and assess the main chemical reactions, mass and energy transport in diffuse and contracted plasma regimes. From model results, it is found that, as pressure is raised, the inhomogeneous gas heating induces significant gradients in neutral and charged species mole fractions profiles. Moreover, the transition from diffuse to contracted plasma is accompanied by a change in the dominant charged species, which favours electron–ion recombination over dissociative attachment. Associative ionization rates increase in the plasma core from diffuse to contracted regime. These processes contribute to the increase in the peak electron number density with pressure, that determines radial plasma contraction.
Reheating in models with
non-minimal coupling
in metric and Palatini formalisms
Authors: Cheong Dhong Yeon , Lee Sung Mook , Park Seong Chan
Published: February 2022

We study reheating of inflationary models with general non-minimal coupling K(ϕ)R with K(ϕ) ∼ √(V(ϕ)) where R is the Ricci scalar and R is the inflaton potential. In particular, when we take the monomial potential K(ϕ) ∝ ϕ
m
with m∈ℤ+, we provide general analytic expressions for cosmological observables. We consider a wide range of non-minimal coupling ξ∈[0,∞) in metric and Palatini formalisms and derive the predictions for cosmological observables and the reheating temperature taking a general equation of state parameter w
reh.
Amplification of primordial perturbations from the rise or fall of the inflaton
Authors: Inomata Keisuke , McDonough Evan , Hu Wayne
Published: February 2022

The next generation of cosmic microwave background, gravitational wave, and large scale structure, experiments will provide an unprecedented opportunity to probe the primordial power spectrum on small scales. An exciting possibility for what lurks on small scales is a sharp rise in the primordial power spectrum: this can lead to the formation of primordial black holes, providing a dark matter candidate or the black holes observed by the LIGO-Virgo collaboration. In this work we develop a mechanism for the amplification of the small-scale primordial power spectrum, in the context of single-field inflation with a step-like feature in the inflaton potential.
Specifically, we consider both the upward and the downward step in the potential. We also discuss the possibility of the strong coupling between perturbations because the rapid changes of the potential derivatives with the time-dependent field value, caused by the step-like feature, could make the coupling stronger. As a result, we find that the perturbations can remain weakly coupled yet sufficiently enhanced if the step realizes the rapid changes of the potential derivatives in some fraction of an e-fold, 𝒪(𝒫ℛ
1/2) ≲ ΔN < 1, where 𝒫ℛ is the power spectrum of the curvature perturbation at that time.
We also discuss the PBH formation rate from the inflaton trapping at the local minimum, which can occur in the potential with an upward step.
Soliton boson stars, Q-balls and the causal Buchdahl bound
Authors: Bošković Mateja , Barausse Enrico
Published: February 2022

Self-gravitating non-topological solitons whose potential admits multiple vacua are promising candidates for exotic compact objects. Such objects can arise in several extensions of the Standard Model and could be produced in the early Universe. In this work, we focus on objects made from complex scalars (gravitating Q-balls/soliton boson stars), deriving analytic solutions in spherical symmetry and comparing them with fully numerical ones. In the high-compactness limit we find that these objects present an effectively linear equation of state, thus saturating the Buchdahl limit with the causality constraint. Far from that limit, these objects behave either as flat space-time Q-balls or (in the low-compactness limit) as mini boson stars stabilized by quantum pressure. We establish the robustness of this picture by analyzing a variety of potentials (including cosine, quartic and sextic ones).
Astrophysical constraints
on compact objects in 4D Einstein-Gauss-Bonnet gravity
Authors: Charmousis C. , Lehébel A. , Smyrniotis E. , Stergioulas N.
Published: February 2022

We study the properties of compact objects in a particular 4D Horndeski theory originating from higher dimensional Einstein-Gauss-Bonnet gravity. Remarkably, an exact vacuum solution is known. This compact object differs from general relativity mostly in the strong field regime. We discuss some properties of black holes in this framework and investigate in detail the properties of neutron stars, both static and in slow rotation. We find that for relatively modest deviations from general relativity, the secondary object in GW190814 is compatible with being a slowly-rotating neutron star, without resorting to very stiff or exotic equations of state. Remarkably, the equilibrium sequence of neutron stars matches asymptotically to the black hole limit, completetly closing the mass gap between neutron stars and black holes of same radius, although the stability of equilibrium solutions has yet to be determined. As a consequence, there exists a universal endpoint for the neutron star sequence, independent of the equation of state. In light of our results and of current observational constraints, we discuss specific constraints on the coupling constant that parametrizes deviations from general relativity in this theory.
Parts of Speech Tagging: A Setswana Relative
Authors: Malema Gabofetswe , Ishmael Ontiretse
Published: February 2022

Setswana qualificatives consists of multiple words. This makes part of speech tagging a challenging task especially for the relative part of speech. The Setswana relative has a wide variety of structure in terms of number of words, form, tense, and negation. A few studies have looked at part of speech tagging for Setswana complex parts of speech including the relative. However, these studies did not explore in detail all the different forms of a relative. In this study, we investigate the different forms of a Setswana relative and convert them into a general pattern. The relative patterns are stored in a trie data structure which is used to detect relative’s parts of speech in a given Setswana sentence. Tests show that most of the relative forms are consistent giving a performance rate of 78% for the test data. The direct relative structure gives a higher performance rate as its structure is simpler and less ambiguous compared to the indirect relative structure.
Recent Advances in Representation Learning for Electronic Health Records: A Systematic Review
Authors: Liu Xiaocong , Wang Huazhen , He Ting , Liao Yongxin , Jian Chen
Published: February 2022

Representation Learning (RL) aims to convert data into low-dimensional and dense real-valued vectors, so as to realize reasoning in vector space. RL is one of the important research contents in the analysis of health data. This paper systematically reviews the latest research on Electronic Health Records (EHR) RL. We searched the Web of Science, Google Scholar, and Association for Computing Machinery Digital Library for papers involving EHR RL. On the basis of literature review, we propose a new taxonomy to categorize the state-of-the-art EHR RL methods into three categories: statistics learning-based RL methods, knowledge RL methods and graph RL methods. We analyze and summarize their characteristics according to the input data form and underlying learning mechanisms. In addition, we provide evaluation strategies to verify the quality of EHR representations from both intrinsic and extrinsic perspectives. Finally, we put forward three promising research directions to promote future research. Overall, this survey aims to provide a profound overview of state-of-the-art developments in the field of EHR RL and to help researchers find the most appropriate methods.
Design of 3DOF Delta Parallel Capture Robot with High Speed and Light Weight
Authors: Jun-lin Ma , Ying Liu , Ying-kun Zhang , Cunming Hao
Published: February 2022

For sucking medicine bottles, according to the particularity of camber surface of the bottle and the sucker, in order to improve the speed, accuracy and stability of capture, this paper presents a 3 degree of freedom Delta parallel robot with high speed and light weight. First, coordinate system of the robot is established, kinematical equationes are obtained based on kinematics analysis and geometric parameter is determined according to specified operation space; Next, trajectory planning is proceeded applying double rounded corner door shape loop which could solve the problem of the wobbling of robot arms; Then, robot structure is designed based on lightweight theory using hollow rod and I-shaped arm; In the end, the prototype is processed with adjustable. Design results show that: capture range is 400 mm x 200 mm, maximum speed is 200 time/min, maximum acceleration is 50 m/s2. Setting operator parameter to the maximum value, repeated positioning experiment is completed. With repeated positioning accuracy 0.385 mm, it is strong evidence that the Delta parallel robot presented by this paper could capture targets accurately, even for smaller ones. The results from this study provide theoretical references for lightweight design and trajectory planning of Delta parallel robot, and because this Delta parallel robot uses only mechanical parts to make this accuracy with no electronic sensor and machine vision module, it lays the foundation for further improvement in accuracy of the Delta parallel robot.
Heat balance analysis of RSG-GAS coolant system due to cooling tower refurbishment
Authors: Sudarmono  , Sutrisno  , Bakhry Syaiful , Hastuti Endiah Puji
Published: February 2022

The RSG-GAS reactor is designed to operate at a power level of 30MW, as stated in the Safety Analysis Report, and currently RSG GAS has been operating for 34 years. Aging of components has been anticipated to ensure the reactor operates safely. Some parts of the structure, system and components (SSC) will experience degradation/aging and must be replaced. Cooling tower is one of them, where the sub components are maintained and tested regularly. Cooling tower aging indication are known from the decreased performance of the reactor cooling system. For this reason, it is necessary to evaluate, both in terms of measurement and calculation analysis, before and after the refurbishment. The efficiency of the cooling tower has been calculated based on the measurement results of the cooling temperature, at the RSG-GAS operation at a power level of 30 MW. From the measurement results, it can be seen that there is a difference in air velocity inlet and outlet of module 1 and module 2. As well as the working temperature of the blower is uneven, the blower temperature ranges from 60.5°C-91.9°C. So that the operation of the RSG GAS could not last long. The efficiency of the cooling tower during the day ranges from 54.72% to 73.23%. The effect of decreasing cooling tower capability can be seen from the calculation results on the performance of each module individually. while its effect on the overall performance is known from the increase in the temperature of the coolant entering the reactor from the HE. The results of the cooling temperature measurement, after refurbishment, show that the cooling tower performance has been able to dissipate heat according to the initial design.
Flame characteristics analysis of a methane gas’ premixed combustion on a ring attached-bunsen burner using ansys fluent
Authors: Sady I E , Widodo A S , Utami Dewi F G , Trismawati
Published: February 2022

Many studies have had been done relating to the Bunsen burner. However there are only a handful of studies which focus on the implementation of a foreign component integrated to a Bunsen burner. Therefore, the effect of such component to the Bunsen burner still need to be investigated further. The study proposes a further analysis on the effects of a ring, primarily its temperature, on the Bunsen burner to the flame characteristic of methane gas. Flame’s temperature, flame’s height, and laminar flame speed are the 3 key properties observed. The study is done using a computer based numerical simulation software Ansys, implementing a 2D Fluent steady state analysis. The variations are the value of the ring’s temperature, which are 400 K, 600 K, and 800 K. The result of the study suggests that for the same equivalence ratio value, the higher the temperature of the ring attached to the burner, resulting in a higher flame’s temperature and laminar flame speed value. Proven by the fact that the 800 K temperature variation has the highest value of both flame’s temperature and laminar flame speed for the same value in equivalence ratio compared to all of the variations. However, a higher ring’s temperature value resulting in a lower or reduced flame’s height formed for the same equivalence ratio. Also proven by the fact that the 800 K temperature variation also has the lowest flame’s height value compared to all the variations at any given equivalence ratios.
Structure and emission properties of Nd3+doped oxyfluorophosphate glasses
Authors: Rajagukguk Juniastel , Rajagukguk Donna Helen , Gultom Rahel Suryani , Simamora Pintor , Situmorang Rappel , Sarumaha Chayani
Published: February 2022

The characterization of the phosphate glass system doped by the active ion Neodymium (Nd3+) has been carried out using the Melt-Quenching method. The composition of the phosphate glass is made according to the chemical formula 64P205-20Li20-15X-1Nd203(X = CaF2and TeO2). Testing of the physical properties of glass is carried out using the Archimedes method. Testing the structural properties of glass using X-Ray Diffraction (XRD) and Fourier-transformed infrared (FTIR). Testing the optical properties of the glass using a UV-Vis spectrophotometer. XRD results show the glass made has an amorphous structure. The FTIR results show that absorption bands occur in the area of 710-772 cm−1, 871-890 cm−1, 990-1020 cm−1,1074-1157 cm−1, and 1240-1255 cm−1. The results of physical testing showed that the glass density increased and the molar volume decreased with the addition of CaF2and TeO2compounds. The highest absorption spectrum is at the transition4I9/2→4G5/2+2G7/2at a wavelength of 582 nm. The lowest direct and indirect bandgap energies are owned by PLTNd (use TeO2) glass, namely 3.30 eV and 3.85 eV. The highest emission spectra are in the two emission band transitions4F3/2→ 4I11/2and4F3/2→4I13/2with wavelengths of 1063 nm and 1334 nm. The highest emission spectrum is produced by PLCNd (use CaF2) glass.
Aging management experience to support reliability of RSG-GAS operation and future NPP in Indonesia
Authors: Hastuti Endiah Puji , Bakhry Syaiful , Sihombing Edison , Sudarmono
Published: February 2022

The aging process will cause a decrease in the reliability and safety performance of the nuclear reactor operation. As a consequence, the quality of service to stakeholders will decline. In order to keep nuclear reactor reliable, systematic activities are needed to manage the aging process that occurs at the GA Siwabessy multi-purpose reactor (RSG-GAS), in Serpong. The activity includes 4 main elements, i.e.: understanding and evaluating the aging process, using aging prevention methods, detection and surveillance methods, and aging mitigation methods. Aging management is carried out at RSG-GAS through routine and periodic maintenance, repair, replacement and monitoring mechanisms. Aging management must be planned from design, construction and commissioning activities to reactor operation. RSG-GAS aging management is carried out in accordance with safety guidelines from the international atomic energy agency (IAEA) and nuclear power regulatory body (BAPETEN) regulations, as well as various vendor documents. The success of aging management is demonstrated by operating parameters that meet operating limit conditions (OLC), and is evaluated through periodic safety assessments. This paper aims to convey the experience of RSG-GAS in aging management, in order to support the reliable operation of RSG-GAS. Experience in the aging management program of the RSG-GAS as long as 34 years, is an important asset in developing the aging management program of future Indonesian nuclear power plants.
Synthesis and material characterization of calcium carbonate (CaCO3) from the waste of chicken eggshells
Authors: Ningrum R A , Humaidi S , Sihotang S , Bonardo D , Estananto
Published: February 2022

Synthesis and basic characterization of calcium carbonate (CaCO3) material produced from the extraction of chicken egg shells is proposed. The studied method is applied for the basic analysis of the mineral CaCO3 in the field of membrane materials. Three basic characteristics of CaCO3 have been investigated, namely microstructure, crystal structure and vibrational modes. Microstructure were measured using a scanning electron microscope (SEM), while crystal structure were measured using an X-ray diffractometer (XRD). Fourier transform infra-red (FTIR) spectroscopies were used to determine the vibrational modes. Experimental results show that the morphology of the sample has the characteristics of a microstructure with a mean grain size of 3 μm, the morphology of the resulting microstructure has a loose spacing between grains so as to provide an empty space between the sample grains. The crystal structure of CaCO3 formed is trigonal and has a crystal size of 53.306 nm, indicating the formation of nano crystals in the sample, while the FTIR spectroscopies data show the appearance of the three highest peaks at wave numbers of 3637 cm−1, 1438 cm−1, and 871 cm−1, which indicates the OH strain functional groups in Ca(OH)2, CO and calcite groups, respectively. Several studies also reported that the hydroxyl and carbonation groups at similar wave numbers were 3643 cm−1, 1445 cm−1 and 877 cm−1, and at 712 cm−1, 876 cm−1, and 1425 cm−1 which correspond to C=C, CO, and CS vibrations.
Design and manufacturing processes of half face motorcycle palm fiber reinforced composite polymer
Authors: Yani M. , Lubis Riadini Wanty , Arfis A , Putra Billy Wintana , Hardiansyah Willy
Published: February 2022

The Results of palm oil mill processing are palm oil and its derivatives which have high selling value. While the waste is oil palm empty fruit bunches (OPEFB), its utilization is still small. This waste is considered to have good potential to be utilized and developed into composite materials. This study aims to design and manufacture a half-face motorcycle helmet from a polymer composite reinforced OPEFB fiber. The method of making motorcycle helmet by hand lay-up, where polymer composite is applied to a motorcycle helmet mold made of wood with 2 layers on the shell of the helmet. The ratio of OPEFB fiber and polyester resin is based on a mass fraction of 10:90. Obtained a half-face motorcycle helmet with a mass of 1.5 kg and the size of the helmet is for an adult head.
Design of room capacity measurement and body temperature detection based on atmega328 microcontroller
Authors: Azhari  , Marbun Hertika , Karolina Rahmi , Hakim Lukman
Published: February 2022

The outbreak of Corona Virus Disease 2019 (Covid 19) cases that occurred from 2020 until now limits the current maximum allowed room capacity, which is only around 25% to 50% of the maximum room capacity. The purpose of this study is to design a device that can detect temperature and limit room capacity automatically as an effort to prevent the transmission of the covid 19 virus. In designing a room capacity measuring device and an atmega328 microcontroller-based body temperature detector with a viewer on an android smartphone. The ultrasonic sensor HC-SR04 is used to measure the capacity of the room to determine the number of people entering and leaving. Then this tool also uses the MLX90614 sensor to detect the body temperature of everyone who wants to enter with the temperature conditions below 38°C. When both sensors have worked according to their functions, the doorstop can be opened. The results of the data obtained on each sensor will be sent to the microcontroller as a control center on a system so that it can be displayed on the LCD and using an additional device, namely esp8266 as a wifi communication module. After testing it can be concluded that the tool works well. The comparison of the results of the MLX90614 sensor with a standard tool. The data obtained is quite accurate with maximum error only 2.2% with the comparison tool.
Identification of earthquake-prone areas as a regional planning study for deli serdang regency
Authors: Barlian Edo , Tarigan Johannes , Nasution Zulkifli , Purwoko Agus
Published: February 2022

The main effect of an earthquake for an area is the loss that has an impact on social, economic and physical conditions. Based on earthquake data from the USGS, the earthquake that occurred in the North Sumatra area would have an impact on the surrounding area, especially in Deli Serdang Regency. Seen from the geological map, the Medan sheet shows that the Deli Serdang area is located in a fault zone. The purpose of this study is to identify earthquake-prone areas as a study in regional planning in Deli Serdang Regency with the target of this research being to provide benefits in policy making and readiness for earthquake risk in Deli Serdang Regency and this research will contribute to science in identifying areas that have the potential for earthquake disasters. The method in this study emphasizes data collection in the form of rock types, land slopes, seismic data in the form of soil acceleration in the bedrock and areas located in the fault zone. These parameters will be weighted and analyzed in order to obtain a model that represents field conditions. Analyzing the data using the overlay method so as to obtain the typology of earthquake-prone areas. The results of the analysis describe the typology of earthquake-prone areas consisting of areas with typology A with a stable classification of 10.45%, typology A with a less stable classification of 39.51%, typology B with a less stable classification of 43.89%, typology C with less stable classification was 4.89%, the area with typology D and unstable classification was 1.25% and the area with typology E classification unstable was 0.02%.
Analysis of mixed stiffness modulus of different asphalt levels for AC–BC pavement layer with pertamina 60/70 asphalt and 60/70 esso asphalt material
Authors: Asfiati Sri , Zurkiyah  , Yani M. , Indrayani  , Prafanti Sri
Published: February 2022

Asphalt/bitumen is a brownies black material, is viscous so it will soften and melt when it gets enough heating. In general, asphalt is obtained from petroleum refining. Pavement construction in Indonesia, both road rehabilitation project, maintenance and construction of roads, generally. Pertamina 60/70 asphalt is used as a binder for the asphalt mixture. Apart from pertamina asphalt, there are several types of asphalt that ore often used in projects in Indonesia, one of which is esso 60/70 asphalt.Esso asphalt is a type of asphalt produced from foreign companies outside of Indonesia, so it is necessary to do a comparative research test on the Marshall Properties and the stiffness modulus of asphalt. The research was conducted to analyze the stress-strain relationship which show the stiffness and strength of the asphalt material by experimenting with several test objects using the Marshall tool. If the value of the stiffness modulus decreases, asphalt aging will occur which causes the pavement to crack easily when receiving heavy loads. The stiffness modulus analysis of the asphalt mixture is an analytic procedure for planning and evaluating the performance of asphalt mixture. Asphalt mixture is a material that is not perfectly elastic, so the use of the term modulus of elasticity (E) is not suitable, instead the term mixed stiffness modulus is used. The data needed is the value of the stiffness of the asphalt content mixture which was tested by the laboratory to obtain the stiffness modulus and asphalt content characteristic.