bluuebunny/crossref_metadata_2025 huggingface dataset:
Direct End-to-End Neurorrhaphy for Wrist-Level Long Nerve Defect with Fixation of the Wrist in Flexion: Technique Note
Authors: Lu Chun-Ching , Huang Hui-Kuang , Wang Jung-Pan
Published: May 2021

Background For a nerve gap, end-to-end neurorrhaphy would either be difficult or would include tension. The use of a nerve graft or conduit could be a solution, but it might compromise the reinnervation. We describe a method for wrist-level ulnar and/or median long nerve injury by fixing the wrist in the flexion position with K-wire (s) to make possible an end-to-end and tension-free neurorrhaphy.

Patients and Methods Two patients had wrist-level ulnar nerve injury for 2 and 3 months and nerve gaps of 2.5 cm and 3.5 cm, respectively, after the neuroma excision. K-wires were used to transfix from the radius to carpal bones, in order to keep their wrists in flexion of 45 and 65 degrees, respectively, with which the tension-free end-to-end neurorrhaphy could be achieved. The K-wires were removed in 6 weeks after surgery, and their wrists were kept in the splint for a progressive extension program.

Results Both patients were noted to have an improved claw hand deformity 4 months after the surgery. The ulnar nerve motor and sensory function could be recovered mostly in the 12-month follow-up. The wrist flexion and extension motion arc both achieved, at least, 150 degree in the 12-month follow-up. There were no complications related to the K-wire fixation.

Conclusion With the wrist fixed in a flexed position, maintaining a longer nerve gap to achieve a direct end-to-end and tension-free neurorrhaphy would be more likely and safer. Without the use of nerve graft, innervation of the injured nerve would be faster.
Investigation of the hepatic development in the coculture of hiPSCs-derived LSECs and HLCs in a fluidic microenvironment
Authors: Danoy Mathieu , Tauran Yannick , Poulain Stephane , Jellali Rachid , Bruce Johanna , Leduc Marjorie , Le Gall Morgane , Koui Yuta , Arakawa Hiroshi , Gilard Francoise , Gakiere Bertrand , Kato Yukio , Plessy Charles , Kido Taketomo , Miyajima Atsushi , Sakai Yasuyuki , Leclerc Eric
Published: May 2021

Interactions between the different liver cell types are critical to the maintenance or induction of their function in vitro. In this work, human-induced Pluripotent Stem Cells (hiPSCs)-derived Liver Sinusoidal Endothelial Cells (LSECs) and Hepatocytes-Like Cells (HLCs) were cultured and matured in a microfluidic environment. Both cell populations were differentiated in Petri dishes, detached, and inoculated in microfluidic biochips. In cocultures of both cell types, the tissue has exhibited a higher production of albumin (3.19 vs 5.31 μg/mL/106 cells in monocultures and cocultures) as well as a higher inducibility CYP450 over monocultures of HLCs. Tubular-like structures composed of LSECs and positive for the endothelial marker PECAM1, as well as a tissue more largely expressing Stabilin-2 were detected in cocultures only. In contrast, monocultures exhibited no network and less specific endothelial markers. The transcriptomic analysis did not reveal a marked difference between the profiles of both culture conditions. Nevertheless, the analysis allowed us to highlight different upstream regulators in cocultures (SP1, EBF1, and GATA3) and monocultures (PML, MECP2, and NRF1). In cocultures, the multi-omics dataset after 14 days of maturation in biochips has shown the activation of signaling related to hepatic maturation, angiogenesis, and tissue repair. In this condition, inflammatory signaling was also found to be reduced when compared to monocultures as illustrated by the activation of NFKB and by the detection of several cytokines involved in tissue injury in the latter. Finally, the extracted biological processes were discussed regarding the future development of a new generation of human in vitro hepatic models.
Design of radiation conversion target for Compton gamma magnetic spectrometer
Authors: Weng Xiufeng , Tan Xinjian , Hei Dongwei , Zhang Xiaodong , Sun Bin , Wei Kun , Liu Xiao
Published: May 2021

This paper analyzes the intrinsic energy resolution, the influence law of multiple Coulomb scattering, the radiation conversion efficiency, and other factors of the Compton radiation conversion target. Based on the essential principle of interaction between gamma rays and matter, the theoretical characteristics and transport law of Compton electrons are analyzed. Through a Monte Carlo simulation, the composition, energy, and angular distribution of electrons emitted from the target surface are calculated; the influence of target parameters, such as target material, thickness, and electron collection angle, on target performance is studied; and then the optimization method of target parameters is established. Finally, the main performance parameters of the Compton radiation conversion target are given. This research reveals how multiple Coulomb scattering angles relate to materials of different types and thicknesses, as well as to the optimal collection angle. A series of optimized parameters for the material, mass thickness, and corresponding energy resolution of radiation conversion target with different conversion efficiencies are obtained.
Unexpected diversity in the sponge-associated shrimps
Authors: Šobáňová Anna , Ďuriš Zdeněk
Published: May 2021

Multigene molecular revision of a series of specimens of the rare spongobiotic palaemonid shrimp genus, Onycocaridella Bruce, 1981, collected predominantly from Papua New Guinea, has doubled the known species diversity to six. Of the previously known species, O. monodoa (Fujino & Miyake, 1969) and O. stenolepis (Holthuis, 1952) were analysed in the present study, whereas sequenceable specimens of the type species, O. prima Bruce, 1981, were not available. The present molecular analysis (combined COI, 16S, H3 markers) recovered six separate genetic lineages, indicating the presence of four undescribed species. Three of the latter are described in the present study. Remarkably higher known species diversity of Onycocaridella is thus recorded from a single geographic region – Papua New Guinea. The increased diversity reported here was discovered by application of complementary collecting techniques (hand picking, stone brushing, dead-coral sorting, suction sampling). One of the present new species is also reported from Australia, and O. monodoa is newly recorded from New Caledonia. A revised diagnosis of the genus and a key to identification of all known species of Onycocaridella are provided.
Carceral-community epidemiology, structural racism, and COVID-19 disparities
Authors: Reinhart Eric , Chen Daniel L.
Published: May 2021

Significance

As jails and prisons remain leading sites of COVID-19 outbreaks, mass incarceration poses ongoing health risks for communities. We investigate whether short-term jailing of individuals prior to release may drive COVID-19 spread. We find that cycling individuals through Cook County Jail in March 2020 alone can account for 13% of all COVID-19 cases and 21% of racial COVID-19 disparities in Chicago as of early August. We conclude that detention for alleged offenses that can be safely managed without incarceration is likely harming public safety and driving racial health disparities. These findings reinforce consensus among public health experts that large-scale decarceration should be implemented to protect incarcerated people, mitigate disease spread and racial disparities, and improve biosecurity and pandemic preparedness.
2′-O methylation of RNA cap in SARS-CoV-2 captured by serial crystallography
Authors: Wilamowski Mateusz , Sherrell Darren A. , Minasov George , Kim Youngchang , Shuvalova Ludmilla , Lavens Alex , Chard Ryan , Maltseva Natalia , Jedrzejczak Robert , Rosas-Lemus Monica , Saint Nickolaus , Foster Ian T. , Michalska Karolina , Satchell Karla J. F. , Joachimiak Andrzej
Published: May 2021

Significance

The 2′-O methyl group in Cap-1 is essential to protect viral RNA from host interferon-induced response. We determined crystal structures of SARS-CoV-2 Nsp10/16 heterodimer in complex with substrates (Cap-0 analog and S-adenosyl methionine) and products (Cap-1 analog and S-adenosyl-L-homocysteine) at room temperature using synchrotron serial crystallography. Analysis of these structures will aid structure-based drug design against 2′-O-methyltransferase from SARS-CoV-2.
An eye-tracking study examining information search in transit maps
Authors: Wang Zheng , Lonsdale Maria dos Santos , Cheung Vien
Published: May 2021

This study investigates the legibility of China’s high-speed railway map through eye-tracking measurement. The information searching process was identified by conducting: (1) Scoping stage – a user performance test and interview to inform the design of the eye-tracking study; (2) In-depth stage – an eye-tracking study. A number of visual design problems with the map have been identified. This research explores user-centered design map solutions and provides detailed design guidance for transit maps. It also demonstrates that eye-tracking is an effective method of evaluating the design quality of a transit map as it can identify design limitations and user needs.
MSIGEN: Multi-Scale Illumination-Guided Low-Light Image Enhancement Network
Authors: Hao Yue , Jiang Xuemei , Hu Jiwei , Lou Ping
Published: May 2021

Images lack of light often show the characteristics of low visibility, low contrast and high noise, due to limited imaging equipment. To address the problem, inspired by Retinex theory, we propose a two-stage method called Multi-Scale Illumination-Guided Low-Light Image Enhancement Network (denoted as MSIGEN). In the first stage, we employ an enhancement module to achieve low-light image enhancement, including a Decom-Net for decomposing into illumination and reflectance, an Adjust-Net for illumination adjustment, a Restore-Net for the illumination fusion map guided reflectance restoration. Secondly, the enhancement module is introduced to refine the initial images to effectively remove visual defects amplified and ensure the naturalness of the image. In addition, extensive experiment results demonstrate the advantages of our method and the effect of this method has reached the state-of-the-art.
Detection of water seepage in lake body using ground penetrating radar method
Authors: Yulianita Dina , Aisyah Rizha Rizky , Wafi Abdurrahman , Setiawan Nugroho Syarif , Mariyanto Mariyanto
Published: May 2021

Ground Penetrating Radar (GPR) is a geophysical method used to identification subsurface condition at a certain depth, using a source of electromagnetic waves in the form of radar. Geoscanners Akula A9000C and Antenna Gecko 60 with 60 MHz antenna frequency were used for data acquisition for this study. Survey data was conducted as many four lines, located on the south and east sides of the lake, with the distance range from 0 to 145 m. This paper reports basic signal processing GPR data using matGPR for the analysis and modelling. The results show that there is anomaly which is suspected as water seepage appear on depth of 2 m. On the lengthwise line, anomalies show on a distance of 20 m and 35 m (line A) and 125 m and 135 m (line B), while on the crosswise line anomalies show on a distance of 35 m and 50 m (line C), 25 m and 95 m (line D). Water seepage can be found in this area as it is formed by alluvial depositional environment, remembering that the characteristics and rocks lithology in this area can stimulate water infiltration process. Water seepage will cause erosion of the lake and can collapse the lake’s structure.
Vertical structure of raindrop size distribution over West Sumatera from global precipitation measurement (GPM) observation
Authors: Ramadhan R , Marzuki  , Harmadi
Published: May 2021

Vertical Structure of Raindrop Size Distribution (DSD) over West Sumatera (99.82 E – 100.82 E; 0.73 S – 0.27 N) was observed from Normal Scan (NS) of Global Precipitation Measurement (GPM) observation during December 2014 to June 2018. This observation was carried out for stratiform and convective rain. The vertical structure of DSD from GPM was described as two gamma distribution parameters, namely, mass-weighted mean diameter (Dm
) and total raindrop concentration (Nw
). In addition, the vertical structure of integral rainfall parameters was investigated from the vertical structure of radar reflectivity (Z). It was found that vertical structure of DSD from NS of GPM observation shown different value for both stratiform and convective rain, for the same rainfall intensity. The NS of GPM estimates larger (smaller) Dm
(Nw
) for convective than stratiform rain. It indicates convective has more large drops than stratiform rain with lower of total drops number for the same rainfall intensity. Furthermore, the gradient of vertically downward from Dm
and Nw
is slightly larger during convective rain than during stratiform rain for all classes intensity. This indicates a more significant growth of raindrop in rain column during convective rain than during stratiform rain over West Sumatera.
Development of technology vermicompost production for the coffee plant Industry
Authors: Zulhipri  , Erdawati  , Purwanto Agung
Published: May 2021

The aim of this study was to convert skin coffee (SC) amended with green waste (GW) and biochar(B) into vermicompost and evaluates their effects on the plant growth coffee. Biochar is a carbon rich product made from the rice husk pyrolysis process at 450°C, green waste eq branch cuttings and leaves from in the garden Universitas Negeri Jakarta and skin coffee from Cibulao coffee farm Bogor, Indonesia. Biochar was mixed with SC and GW in different proportion i.e., 6%,8% and 10% b along with control and allowed to pass through earthworm guts during two months. Vermicompost was characterization with SEM EDX and chemical content. The 8% biochar addition rate achieved maturity of vermicomposting and resulted in the highest quality vermicompost based on parameters such as organic C, C:N ratio, total N, P, K content and pH, were compared to a vermicompost as control. in the cultivation of plant growth, physiological parameters and morphology plant coffee growth such as number of leaf, heigh plant, steam diameter and shoot dried weight.
Deformation analysis for Padang earthquake using GPS data
Authors: Iqbal Rahmat , Syafriani  , Arisa D , Setiadi B
Published: May 2021

On September 30, 2009, an Mw 7.6 earthquake occurred off the coast of Sumatra. This earthquake caused deformation in the area around the center of the earthquake. Surface deformation in the area around the epicenter was Analyzed carried out using GPS data from the SuGAr (Sumatran GPS Array) network. The observed SuGAr stations were TIKU, PSKI, NGNG and MSAI. Data processing used GAMIT/GLOBK software. GPS data were observed for 100 days before and after the main earthquake occurrence. The measurement results indicate that the MSAI and NGNG stations in Mentawai deformed towards the south-weast direction, varies between 38 - 50 mm, and TIKU and PSKI stations on the mainland of Sumatra were deformed in north-west directions, varies from 5 - 12 mm. This indicates that this Earthquake deformed the area of Western Sumatra and nearby Mentawai regions, in Siberut Island.
Analysis of validity and practicality test of physics enrichment e-book based on CTL and enviromental factor
Authors: Asrizal  , Desnita  , Darvina Y
Published: May 2021

Teaching in the 21st century should have context, use multiple learning resources, and use ICT. This teaching will support the attention, involvement, and motivation of students. However, learning resources for physics enrichment and the use of ICT in physics teaching were still limited. The solution to this problem is to develop a physics enrichment e-book. The research objective was to determine the validity and practicality of the physics enrichment ebook on the theme of motion. This research method can be categorized into research and development. The development model in this research was included in the ADDIE model. The research instrument consisted of two parts, namely the validity assessment questionnaire sheet from the experts and the practicality assessment questionnaire sheet from the physics teachers and students. The research data were analyzed using descriptive statistics. From the results of data analysis, it can be stated that two results from this research. First, the validity of the physics enrichment e-book can be classified into a very good category in the aspects of learning material, presentation, language, graphics, and e-book criteria. Second, the practicality of using physics enrichment e-books based on CTL and environmental factor can be included in the very good category according to both physics teachers and students in the aspects of usability, easy of use, appealing, and clarity. Therefore, physics enrichment e-book based on CTL and environmental factor has met the high generic quality criteria of intervention in the components of validity and practicality.
The analysis of depth high school physics material in terms of standars for the development of earthquake theme physics e-books
Authors: Perwita D P , Fauzi A
Published: May 2021

The aim of this study was to determine the current level of depth of the material compared to standard books, if the physics material was superficial, it will be added with standard material. So, before developing an earthquake-themed physics e-book, it was necessary to conduct a depth analysis of high school physics material in terms of standard material. The population of this study was a high school physics book and a physics standard book, with a sample of two high school physics material books class X semester 1 based on the 2013 curriculum and two physics standard books. This study was descriptive qualitative in nature, using a sheet instrument of physics material depth analysis in terms of standard material. The data collection techniques were used documentation and content analysis. Based on the analysis, it was found that the physics material for class X semester 1 was still in the deep enough category. This was evidenced from the results of the depth analysis of physics material in terms of standard material that basic competence (BC) 3.1, 3.2, 3.3, 3.4, 3.5 and 3.6 with the percentage of depth respectively 20%, 87%, 47%, 60%, 60%, and 53%. Therefore, shallowness in physics material will be complemented by standard material, thereby improving the quality and having a high level of depth in the high school physics e-book in the development of earthquake physics e-book. So, the next study to be carried out is to develop an earthquake-themed high school physics e-book.
Analysis of learning media based electronic for developing of physics e-book with earthquake theme
Authors: Yanti Y , Fauzi A
Published: May 2021

Education always tries to take advantage of technology in the learning process according to the needs of students and teachers. Teachers and students need learning media based electronic to minimize the limitations of space and time, and prepare students mentally in the face of natural disasters. This study aims to analyze learning media based electronic as a preliminary study for the developing of physics e-books with earthquake theme used in physics learning. This research uses a quantitative descriptive methods with the population being all students of class X at SMAN 2 Ranah Pesisir and the sample selected using a purposive sampling technique. The instrument used was a questionnaire about learning media the distributed to students that included thirty five statement. The results showed that the quality of technical, content and purpose were in good category with values of 73.09%, the quality of learning were in good category with values of 74.30% and learning media based electronic were in simply category with values of 68.97%. These results indicate that the learning media based electronic need to be further improved. So, further research needs is the developing of physics e-book with earthquake theme for students.
The validity of the science edupark E-Book with a scientific approach based on Padang Beach tourism destinations
Authors: Elvisa Gita Oktia , Rifai Hamdi
Published: May 2021

Learning science by utilizing tourist destinations can observe objects and phenomena in a more real way. Tourist destinations as a source of learning in the form of educational tours are called edupark. This research aims to produce a valid science edupark e-book. Validity is needed to test a study. The validity tested in product development is a material substance, appearance feasibility, presentation feasibility, and language. The edupark e-book validation was carried out by three experts. The research conducted was Design Research with the type of Development Studies using the Plomp model with the steps of Preliminary Research, self-evaluation, expert review. The research instruments were the validity instrument sheet and the edupark e-book validation sheet. Analysis of the data from the results of the validation by the validator shows that each aspect of validity has met the valid category. This shows that the edupark e-book developed meets validity aspects, namely aspects of material substance, feasibility of appearance, feasibility of presentation, and language. Thus, the edupark e-book developed is valid for use in learning.
Identification of students’ misconception about light using a four-tier instrument
Authors: Maison  , Asrial  , Susanti N , Effrita A , Tanti
Published: May 2021

The research objective is to make a valid and reliable identification of junior high school students’ misconceptions about light. The four-tier light instrument (FTLI) was administered to 456 students from two junior high schools in Jambi, Indonesia. Data were analyzed to obtain the percentage of students who have scientific concepts and misconceptions. The results indicated that only 7.7% understood the concept well, and 12.1% had misconceptions about light. The remaining students were categorized as experiencing false positives, false negatives, and lack of knowledge. There are 12 types of misconceptions about the light that can be identified. Some of them are: (1) Light cannot reach faraway places, but distant observers can see the light source; (3) The distance traveled by the candles during the day is shorter than at night; and (3) The color vision of an object is not determined by the color of the light hitting the object.
Implementation of constructivism approach in physics learning on students’ critical thinking ability of junior high school students
Authors: Nurpatri Y , Muliani D , Indrawati E S
Published: May 2021

The background of this study is the problem of education in pandemic of Covid 19 where the students should study from home. The students are tended to extra learn and they are asked to understand and comprehend the material deeply by themselves. One of learning approach that can solve their problem is by implementing constructivism approach, especially in physics learning. This study aims to analyze previous studies related to implementing constructivism approach in improving students’ critical thinking ability and to obtain sources to develop physics learning module about constructivism approach for grade VIII. This research method is a meta-analysis with a sample of 10 articles in national and international journals. The data collection is done by collecting and classifying similar scientific articles and then analyzing them. The result of study shows that there are 8 out of articles used experimental research, and others used field research and classroom action research. Furthermore, there are 40% of articles show the effectiveness of constructivist approach to improve students’ critical thinking ability in physics learning such as students can express their ideas by discussing with others students, they can make a conclusion after doing experiment activity, and they train to express their mind by debating. In conclusion, constructivism approach can improve students’ critical thinking ability and it is needed developing beneficial physics module to get more improvement and to be a source in physics learning.
Development of online learning tools based on problem solving on circular motion materials
Authors: Serevina V , Khofiya N
Published: May 2021

Online learning device is a device used in the online learning process. During the Covid-19 pandemic, teachers are required to change the learning system directly into online learning. This research aims to developing online learning tool based on problem solving in effective circular motion material in the midst of the covid-19 pandemic. This learning tool was made online in order to facilitate teachers and students to conduct teaching and learning activities on physics subject matter by using problem solving learning models. Learning tools were validated by three experts, namely media experts, material experts, learning experts and one physics teacher, and tested on students. The trial subjects were carried out in class X SMA as many as 25 students. Data collection instruments use a questionnaire guide through Google’s forms. The development of this research includes ADDIE research with the stages of development: 1. Analysis, 2. Design, 3. Develop, 4. Implement, 5. Evaluate. From the results of research on the development of problem solving based online learning tools on circular motion material obtained learning devices (learning implementation plan, student activity sheet and online media) have been tested for eligibility by experts and field trials with good criteria and are suitable for use.
Validity of student worksheet inquiry based learning model with multi-representation approach integrated scientific literacy for grade XI physics learning on 21st century
Authors: Septiani T , Yulkifli
Published: May 2021

Student worksheet is a learning resource that guides student during investigations or problem solving. Learning activities will be successful if they are carried out with the right learning model and learning approach as well as supporting literacy skills. Based on the analysis of the needs and characteristics of student, and the limitation of previous validation studies, student worksheet based on the inquiry-based learning model with an integrated multi-representation approach to scientific literacy can be a problem solution. The purpose of this study was to produce a worksheet based on an inquiry based learning model with an integrated multi-representation approach to scientific literacy in valid category. This research method uses descriptive statistics. The instrument was used a validation sheet filled out by experts. The validity of student worksheet obtains on the feasibility of content, presentation, language and graphic components. The average of the four components of student worksheet validation was 0.81 by development experts. In this way, it can be said that student worksheet inquiry-based learning model with an integrated multi-representation approach of scientific literacy is in valid category.
Hand-arm vibration transmissibility measurement from the petrol driven motorboat engine
Authors: Isa M S M , Mazlan A Z A
Published: May 2021

Petrol driven motorboat engine consisted of direct handle-engine mounting mechanism which exposed the operators to the high level of vibration and can lead to the Hand-arm Vibration syndrome (HAVs). The transmitted vibration from the engine to the handle with natural frequency excitation making the transmitted vibration worsen. This study is focusing on the vibration analysis of the 3.3 HP motorboat engine and the transmitted vibration to the operator handle in specific directions and frequency ranges. A lab-scale experimental rig with motorboat engine is set-up to represent the actual operation of the motorboat engine. Experimental Modal Analysis (EMA) is conducted at the motorboat handle to obtain the natural frequencies in y and z axis directions. Two levels of engine speed (Speed 1: Low and Speed 2: High) are taken into consideration for the vibration measurement of both engine and handle in x, y and z axis directions. From this study, the natural frequencies of the handle are determined within 75 – 80 Hz. For the vibration spectral measurement, the engine has produced high vibration in x and y axis directions, whereby the transmitted vibration to the handle is worst in y axis direction. At Speed 1, the engine excited the vibration within frequency range of 45 – 50 Hz while by increasing the engine to Speed 2, the vibration peak shifted to 95 – 100 Hz with higher vibration amplitude. In overall, the vibration transmissibility at the handle are significant between the frequency range of 0 – 100 Hz (above 1) which can result the HAVs among the operators if no necessary action been taken.
Acoustical periodic test of sound level meter based on smartphone application using free-field method
Authors: Dwisetyo B , Hermawanto D , Putri C C , Rusjadi D , Palupi M R , Utomo F B , Prasasti N R
Published: May 2021

The number of smartphone-based application software for noise measurement has been increasing recently. Some application software has complete features of the sound level meter such as frequency weighting and time averaging. They have been used for field noise measurement. However, the reliability of the smartphone-based sound level meter as a measurement instrument has not known yet. In this paper, we tested the smartphone-based sound level meter application software according to the international standard for sound level meter calibration IEC 61672. The parameter of self-generating noise, frequency weighting, and long-term stability in a fully anechoic chamber was measured. We evaluated the class of the smartphone-based sound level meter from the deviation of the measured parameter with the tolerance value described in the standard. The practical implementation of the calibration method is also discussed.
Design of ECG Front End Amplifier Based on CMOS OTA
Authors: Zhang Zekun , Meng Fanxiang , Fan Luyuan
Published: May 2021

The low-noise and low-power amplifier, an important part of ECG recordings, remains a vital challenge in the biomedical instrumentation amplifier field. This paper describe a method of using the capacitive feedback structure and the MOS-bipolar pseudo-resistor to reject the DC offset and amplify signals down to the milli-hertz range. This study used the noise efficiency factor (NEF) to quantify the tradeoff between power and noise. Fabricated in a 180 nm CMOS process, the amplifier consumes 1.44 µW, and achieves the input referred noise of 3.89 µVrms The calculated NEF is 18.07, while the corresponding to common-mode rejection ratio (CMRR) is 87.72 dB. The device achieves low-noise, low-power and appropriate CMRR, which provides a reference for the design of biomedical instrumentation amplifier.
Modeling and Simulation of Lithium-ion Battery Considering the Effect of Charge-Discharge State
Authors: Jin Yin , Zhao Wenchun , Li Zhixin , Liu Baolong , Liu Liu
Published: May 2021

Establishing an accurate battery equivalent model is an important link in the development of battery management system (BMS). The second-order RC equivalent circuit model can accurately describe the dynamic characteristics of the battery. Considering the influence of state of charge (SOC) and battery charging and discharging state on the model parameters, the battery model parameters in charging state and discharging state are identified separately through battery performance test experiments. The equivalent circuit model of lithium ion battery with variable parameters is established by Simscape language, and simulation analysis is carried out. The results show that, considering the influence of battery charge and discharge state, the error of the model is small and the accuracy of the model is improved.
Luminescence Properties of Lu3+ doped Nd: YAG Transparent Ceramics
Authors: Jia Wentao , Wei Qinlei , Zhang Hongbo , Su Chunhui , Ren Guozhong , Zhao Mengjie
Published: May 2021

Lu2O3 doped Nd: YAG transparent ceramics were prepared by solid-state reaction and vacuum sintering. Ionic size compensation was investigated by comparing the X-ray diffraction patterns (XRD) and Raman spectroscopy (Raman) of (Nd0.06LuxY2.94-x)3Al5O12 ceramics. The micrographs and element mappings of ceramics samples sintered at 1750°C for 50 h were analyzed by scanning electron microscope (SEM) and X-ray energy dispersive spectroscopy (EDS), respectively. The emission peak intensity of 1064 nm is the largest, which corresponds to the 4F3/2→4I11/2 transition of Nd3+. Fluorescence spectra and decay curves show that the fluorescence intensity was the highest when the concentration of Lu2O3 was 0.02, and the fluorescence lifetime was 193.92 µs. The elimination of lattice distortion is beneficial to the improvement of fluorescence properties, which can be attributed to ionic size compensation of Lu3+.
Effect of NBTI on the Electrical Characteristics and Trap States of Low Temperature Poly-silicon Thin Film Transistor
Authors: Wang Si , Zhu Hui , Li Rui , Liu Jie , Liu Zheng , Li Dong , Zhang Zhirang
Published: May 2021

Polysilicon thin film transistors have broad application prospects in high-performance flat panel displays and flexible wearable devices due to their high carrier mobility and good stability. However, due to process conditions and other reasons, there are traps inside, and under some electrical stress conditions, its electrical properties will degrade. Here we report the changes in electrical characteristics of p-type polysilicon thin film transistors with stress time at a negative gate voltage of -20V and a temperature of 60°C. It is obtained that the transfer characteristics of the p-type polysilicon thin film transistor move in the negative direction with the increase of Negative Bias Temperature Instability time, and with the increase of SS degradation, and the total trap state inside it is calculated by SS, which provides a theoretical basis for improving the reliability of the device.
Preparation and Luminescent Properties of Tb4O7: CaWO4 Glass Ceramics
Authors: Wei Qinlei , Ma Chaoyu , zhang Cong , Zhao Mengjie , Zhang Zhongxing , Su Chunhui
Published: May 2021

Tb4O7: CaWO4 glass ceramics with CaWO4 (41–1431) as the main crystalline phase were prepared by the melt crystallization method. The effects of holding time on the crystal phase, transmittance, and fluorescence intensity of glass ceramics were studied. As the increase of holding time, the crystal phase does not change, the transmittance decreases gradually, and the fluorescence intensity first increases and then fade. The optimum heat treatment conditions were determined: heat treatment at 750°C for 70 min. Tb4O7: CaWO4 glass ceramics exhibit blue, green, and red light under the excitation of 245 nm light, and the green light emission at 545 nm is the strongest, which is attributed to the 5D4 →7F5 transition of Tb3+. Under the same heat treatment conditions, the emission spectra of Tb4O7 with different doping concentrations were studied, and the optimum doping concentration was determined as 0.6 mol%.
A review of technologies for high efficiency silicon solar cells
Authors: Sui Muchen , Chu Yuxin , Zhang Ran
Published: May 2021

Solar power, an emerging representative of sustainable resources, remains a critical solution to the growing requirement for energy. In recent years, huge efforts have been devoted to developing solar power conversion, leading to the rapid development of the global photovoltaic (PV) market. As the first-generation solar cells, silicon solar cells, particularly crystalline silicon (c-Si) solar cells, still dominate the PV industry. However, many factors constrain their efficiency to a great extent, including the surface recombination of photogenerated electrons and holes and the reduction of light absorption on the front surface. To overcome these problems, many techniques have been investigated. This paper presents an overview of high-efficiency silicon solar cells’ typical technologies, including surface passivation, anti-reflection coating, surface texturing, multi-junction solar cell, and interdigitated back contact solar cell. The working principles, characteristics, and some recent research of these techniques are discussed in this article.
Effect of Multidirectional Forging on Microstructure and Properties of AZ40 Alloy
Authors: Shengxing Zhi , Jiawei Yuan , Xinggang Li , Yongjun Li , Minglong Ma , Guoliang Shi , Kui Zhang
Published: May 2021

AZ40 alloy was operated with the plastic deformation by multidirectional forging (MDF). The evolution rules of microstructure and texture during forging were analyzed by means of metallographic microscope and electron backscattering diffraction (EBSD), and the evolution mechanism of texture during forging is explored. The results show that, with the increase of passes of forging, the strength of the basal texture decreases. After four passes of forging, the original {0001} basal texture is changed to {101̄0} and {21̄1̄0} cylindrical texture, and the Schmind factor of the alloy reaches the maximum. Through multidirectional forging, the anisotropy of the alloy is weakened, and the mechanical properties of each texture are improved compared with that of the extruded state. After four passes of forging, the plasticity of the alloy is the best and the elongation ratio reaches the maximum, which is 32.0%, 29.2% and 27.0%, respectively.
Antenna Modeling and Simulation Method Analysis and Research
Authors: Xianhao Zhang , Kang Guo , Zhongmei Luo
Published: May 2021

Antenna is an indispensable equipment in radio communication, radio broadcasting, radio navigation, radar, remote control and other radio systems.The significance of the simulation of smart antenna system is not only to verify various technologies of smart antenna and find problems, but also to evaluate the performance of various advanced signal processing algorithms through the processing of experimental data, which can provide strong support for the smooth development of smart antenna research.In this paper, the research of antenna simulation mainly includes the definition of antenna, the development course of antenna, the achievements of antenna research and the direction of current exploration.
TTT Curve of Ti-6Cr-5V-5Mo-4Al-1Nb Alloy
Authors: Yue Song , Xuefei Cui , Yang Yu , Xiaoyun Song , Yumeng Luo , Wenjun Ye , Songxiao Hui
Published: May 2021

In order to study the aging hardening characteristics and isothermal aging process of Ti-6Cr-5V-5Mo-4Al-1Nb alloy the time-temperature-transformation (TTT) curve of the alloy was measured by aging hardness method, and the microstructure changes during isothermal process were analyzed by XRD and SEM. It was found that the alloy had a high aging response speed at other aging temperatures except for the slow aging at 300°C and 400°C. When the aging time is prolonged at medium and low temperatures, the alloy can also produce the same aging strengthening effect as that at medium temperature aging, indicating that the temperature window of the alloy aging is wide, the aging strengthening effect is good, and it has the operability of heat treatment strengthening, so it is an ideal structural material. The isothermal aging transformation curve of the alloy is C type, and it can be obtained from the figure that the nose temperature is about 545°C
Rapid fabrication of submillimeter ultrathin CdI2 flakes via a facile hot plate-assisted vapor deposition method
Authors: Zhao Mei , Qiao Liang
Published: May 2021

As an important member of cadmium-based halides, two-dimensional (2D) CdI2 has drawn widespread attention due to its excellent optoelectronic properties. However, the large-size growth of ultrathin CdI2 flakes remains a huge challenge. Here, a facile hot plate-assisted vapor deposition (HPVVD) method is developed to synthesize submillimeter ultrathin CdI2 flakes. The photodetectors based on CdI2 flakes exhibit extremely low dark current (0.53 pA), ultrafast response speed (<2 ms) and good stability. The proposed HPVVD method may open a new avenue to prepare 2D layered metal halides.
Research on 5G related technologies under the new generation of information technology
Authors: Yang Rui , Hu Ruihan , Li Yuhong , Xie Weisheng , Xu Yongqian
Published: May 2021

At present, 5G refers to a vital direction for evolving and upgrading new generations of information technology, and the Industrial Internet critically supports the fourth industrial revolution. 5G has acted as a novel driving force to lead the innovation and stimulate the novel types of information. From a technical perspective, in the 5G field, ultra-low-loss high-reliability copper-clad laminate materials employed in 5G high-speed communications (56Gbps, 112Gbps), 5G metamaterials and low-loss high-performance RF technology, and 5G low-loss magnetoelectric functions. For materials and devices, multi-module integrated printed circuits for 5G communication base stations, manufacturing of 5G communication optoelectronic integrated cables, and multi-channel high linearity and large dynamic range RF optical transceiver integrated modules in terms of 5G mobile communication will show critical significance, as well as in smart agriculture application and demonstration. From an application perspective, China has made it clear that it will start 5G commercial use in 2020, and has issued 5G licenses ahead of this year, which is also leading in the world. 5G fully complies with the future trends of human progress, social development and economic growth. Inevitably, its large-scale applications will be achieved and will expand to a wide range of industries and fields, extended to all aspects of the economy and society, alter human consumption patterns, and transform human production, which can provide a powerful means for the high-quality development and governance of society.
Real time Machine Learning Approach for a Smart Door Unlocking Using Face recognition System
Authors: Rayavel P , Sivakumar A , Gopirajan P V , Surenderanath S , Rathnavel P
Published: May 2021

This proposed framework goes about as a home security framework for both Person location and gives security to entryway access control by utilizing facial acknowledgment for the home climate. The more peculiar’s face is distinguished inside a home climate accomplished by catching a picture from a web camera and handling will be done on caught pictures. The web camera catches the arrangement of pictures when the individual comes before the entryway. The caught picture is analyzed utilizing our face acknowledgment calculation model. In the event that the individual is the approved one, at that point the entryway is opened. Then again, if the individual isn’t the approved one. The picture of the individual is shipped off the power in the event that he perceives the individual and wants to open the entryway. He can distantly get to the entryway and permit the individual in.
Classification of remote sensing images using CNN
Authors: Cherian Aswathy K , Poovammal E.
Published: May 2021

A number of factors can influence the classification of images. The effective outcome or valuable information from multi-source data for better earth exploration becomes a fascinating yet challenging problem when a list of remotely sensed data sources is available. Efficient Remote Sensing Images (RSI) classification has been the foundation for remote sensing applications. A range of classifiers are used to realize the classification of several types of remote sensing image targets. Better classification of targets is critical in both military and civilian sectors. In this paper, the focus is on summarizing the main advanced approaches used to enhance classification precision. The result shows that the Convolutional Neural Network outperforms all the other traditional classification methods.
Investigations on Joining of High Density Poly Ethylene Sheets using Resistance Welding Technique
Authors: Pradeep K. , Panicker Sudhy S , Panneerselvam K , Asokan P.
Published: May 2021

As a result of growing potential for high performance applications, parts made of HDPE materials is gaining greater interest for industry. Hence, the studies on joining of HDPE has got much significance. In this work, resistance welding of HDPE sheets was performed focusing on the governing set of parameters, current, pressure and time. Design of experiment (DOE) is done using full factorial design. The Analysis of Variance (ANOVA) was done with shear strength of weld as main parameter with the assistance of MINITAB software. Optimum parameters were identified in the study were medium level parameters produced good strength and better finished welded samples. Microstructure taken through Scanning electron microscopy (SEM) was supportive for this observation as there was a uniform flow of HDPE material without any void around the implant SS mesh for the best weld condition. The Finite element (FE) modeling of the resistance welding process was also performed using ANSYS to predict the thermal distributions occurring during the process depending on different levels of current and time inputs.
Design and fabrication of six axial arm robot
Authors: Gunasekaran K N , Vasu C , Ram N S Vishnu , Tharun Athi Raj G , Vijayamoorthi R S
Published: May 2021

Industrial revolution 4.0 is paradigm shift towards automation to cater the needs of ongoing demand in industrial production and to meet the requirements of exponential increase. In line with that six axial robotic arm can pave the way to complete the laborious task with in stipulated time. Six axial robotic arm it has a six axial robotic arm driven by six servomotors; a simple 6-DOF motion can be obtained. Robotic arm encompass of mechanical structure and control unit, Control unit controls whole motion of the system. It has two pieces of plastic gears, motors linkages tightened with fasteners and some sophisticated combination of laser cutted acrylic components. This fabricated model has the applications of robotic arm are pick and place spot welding, spray painting etc. The main objective of this paper is to propose a design and fabricate a six axial arm robot using servomotors which helps in the movement of links also the arm is allowed to extend freely with base fixed. The Arduino board connected to the motor to inspect and control the process
Design, Analysis, Manufacturing and Testing of a SCARA Robot with Pneumatic Gripper for the Poultry Industry
Authors: Prakash Amal , Rajendran Anikesh , Pranav V K , Sreedharan Pramod
Published: May 2021

Soft robotics is replacing conventional robots in fields requiring interaction with fragile objects. Namakkal district of Tamil Nadu is responsible for over 90% of egg exports in India. Most of the eggs are processed and palletized manually which causes a lot of money on human labor. This paper discusses the design of a SCARA robot which uses asymmetric flexible pneumatic bellow actuator (AFPBA) to palletize the eggs to reduce the processing time and human labor. The design, analysis, manufacturing and testing details have been provided. The manufactured prototype was able to successfully lift 200 grams without slippage.
Design Optimization and Analysis of External Corrugation and Geometry of Asymmetrical Bellow Flexible Pneumatic Actuator
Authors: Pranav V K , Prakash Amal , Rajendran Anikesh , Sreedharan Pramod
Published: May 2021

Pneumatic soft actuators are a highly researched topic in soft robotics. The paper discusses the design and analysis of an Asymmetric Flexible Pneumatic bellow Actuator (AFPBA). This kind of actuator is cheap, easy to produce, reliable and durable. Soft grippers commonly use this actuator to pick fragile objects. The objective is to design an actuator which produced the maximum bending and study the effect of external corrugation and eccentricity on the actuator to select the optimal design. Optimum eccentricity has been determined by two factors – bending and stability. The model has also been tested at different pressures. Nitrile rubber was used as the material to design and analyze the actuator. Finite element analysis was employed to conduct the structural analysis of the actuator. In conclusion, an actuator with a semicircular cross-section and semi-circular corrugation for the bellows gave the maximum bending. For the particular design selected with an eccentricity of 0.87 provided the maximum bending of 30.764 degrees at working pressure (5 bar).