Microwave Characteristics Analysis of Typical Photosensitive Material InP under Weak Light Irradiation Based on Quasi-Optical Resonator

Yafeng Li,En Li,Chengyong Yu,Chong Gao,Gaofeng Guo,Yong Gao 대한금속·재료학회 2020 ELECTRONIC MATERIALS LETTERS Vol.16 No.2

In this paper, the microwave characteristics of typical photosensitive material InP under diff erent light irradiation are studied. The measurement sensor is a refl ection-type hemispherical quasi-optical resonator with an operating frequency range from 20to 40 GHz, an operating mode of TEM 00q , and a quality factor of 18,000 or more. For the short-time irradiation experiment,the variation of InP microwave characteristics with the irradiation power of 20 mW, 60 mW, 100 mW, and 200 mW, is studiedby frequency-domain and time-domain scanning methods, respectively. The measurement results indicate that the microwavecharacteristics of InP change signifi cantly even under weak light irradiation. Taking 100 mW and 200 mW irradiation poweras examples, the long-time irradiation experiment performed on InP lasting 1.5 min is carried out. The measurement resultcurves clearly show the infl uence of the thermal and non-thermal eff ects on the InP microwave characteristics at the instantof the monochrome light source opening and closing and during irradiation. Furthermore, the temperature distribution ofInP during 200 mW irradiation is real-time imaged by a thermal infrared imager to verify the existence of thermal eff ectduring irradiation. The measurement results are in good agreement with the theoretical analysis.

Cluster Analyses of Tropical Cyclones with Genesis in the South China Sea Based on K‑Means Method

Yafeng Yin,Yangyang Yong,Shandong Qi,Kai Yang,Yizhao Lan 한국기상학회 2023 Asia-Pacific Journal of Atmospheric Sciences Vol.59 No.4

Tropical cyclone (TC) with genesis in the South China Sea (SCS) has been a major concern because of their high landfallfrequency and associated serious hazards to the surrounding coastal areas. The classification of TCs from records of historicaltracks is an important way to obtain their characteristics and to help predict their future behavior. According to the generationlocation, intensity, direction, and track length of TC, TCs with genesis in the SCS from 1950 to 2020 are classified into fourclusters by the K-means clustering method, including northwestward track cluster A, westward track cluster C and two longnortheastward track clusters B and D. The landfall probability, peak season, climate trend, lifespan, maximum wind speed,and power dissipation index show a significant distinction for each cluster. All clusters had a landfall probability exceeding50%, with the highest probability in cluster A (90.44%), followed by cluster C, cluster B, and cluster D with the lowestprobability (54.55%). The clustering results indicate that tracks of TCs are strongly affected by the distribution pattern of theWestern Pacific Subtropical High. When the WPSH moves southward, the southwesterly anomalies provide a significantlyfavorable steering flow for TC northeastward. Conversely, the WPSH located northward in July-September, the strongsoutheasterly anomaly favoring the northwestward movement of TC. From October to November, the WPSH shrinking insize gives way to the prevailing anomalous easterlies that steer the TCs westward. Further concerning the influence of TCsin the different clusters by the WPSH movement will be helpful for prediction in terms of the occurrence, track and landfallprobability of TCs in the SCS.

Introduction to the Special Issue on China’s Relations with Its Neighbors: Historical Perspectives on Contemporary Issues

( Yafeng Xia ) 경남대학교 극동문제연구소 2018 ASIAN PERSPECTIVE Vol.42 No.4

Deep reinforcement learning based resource allocation in C-V2X

Yafeng Deng,Youngjune Choi 한국통신학회 2020 한국통신학회 학술대회논문집 Vol.2020 No.2

Recently, the C-V2X is defined in the release 15. C-V2X provides semi-persistent scheduling (SPS) to handle the vehicle-to-vehicle communication. The state-of-the-art evaluated SPS can obtain over 80% packet delivery ratio (PDR) with the transmission range of 250 m. However, it is yet not reliable enough to handle safety message transmission like basic safety message (BSM) which requires nearly 100%. In this work, we use deep Q network (DQN) to conduct resource allocation based on SPS to improve the reliable transmission of BSM. Specifically, the DQN is used to determine whether the reserved resource blocks should be re-selected or not so that the merging collision can be prevented. The simulation results show that PDR is improved.

Introduction to the Special Section on China's Relations with Its Neighbors: Historical Perspectives on Contemporary Issues

Yafeng Xia 경남대학교 극동문제연구소 2019 ASIAN PERSPECTIVE Vol.43 No.3

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Review : Improving Protein Production on the Level of Regulation of both Expression and Secretion Pathways in Bacillus subtilis

( Yafeng Song ),( Jonas M. Nikoloff ),( Dawei Zhang ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.7

The well-characterized gram-positive bacterium Bacillus subtilis is an outstanding industrial candidate for protein expression owing to its single membrane and high capacity of secretion,simplifying the downstream processing of secretory proteins. During the last few years, there has been continuous progress in the illustration of secretion mechanisms and application of this robust host in various fields of life science, such as enzyme production, feed additives,and food and pharmaceutical industries. Here, we review the developments of Bacillus subtilis as a highly promising expression system illuminating strong chemical- and temperatureinducible and other types of promoters, strategies for ribosome-binding-site utilization, and the novel approach of signal peptide selection. Furthermore, we outline the main steps of the Sec pathway and the relevant elements as well as their interactions. In addition, we introduce the latest discoveries of Tat-related complex structures and functions and the countless applications of this full-folded protein secretion pathway. This review also lists some of the current understandings of ATP-binding cassette transporters. According to the extensive knowledge on the genetic modification strategies and molecular biology of Bacillus subtilis, we propose some suggestions and strategies for improving the yield of intended productions. We expect this to promote striking future developments in the optimization and application of this bacterium.

Estimation of remaining energy and available power for Li‑Ion battery packs considering energy consumption by heat convection

Yafeng Zheng,Chunyu Wang,Shijie Sang,Suoqing Yu 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.1

To realize the efficient use of battery residual energy, this paper attempts to estimate both the state of energy (SoE) and the state of available power (SoAP) for li-ion battery packs. First, the parameters of a 1st-order equivalent circuit model are identified online where the charging and discharging resistances are separately modeled. Then a state of energy estimator, considering the energy dissipation by heat convection, is designed using an unscented particle filter. Afterwards, multiple constraints in terms of cut-off voltages, recommended residual energy, extreme currents, and powers are incorporated to aid in SoAP prediction. Experiments on a 4-cell battery pack using a high-dynamic load profile show that the SoE estimator is reliable against various working conditions. The predicted SoAP with different time horizons and at different temperatures can avoid the conflicts with the preset constraints while giving reliable predictions.

Characteristics of different bacteria and their induced biominerals

Yafeng Rui,Chunxiang Qian 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.115 No.-

Microbially induced carbonate precipitation (MICP) has a wide range of applications, and research on themechanism of bacterial action has a positive effect on the efficient application of this technology. In thisstudy, four different mineralized bacteria were selected, and the bacterial solution cultured for 30 h, theOD value of the bacterial solution reaches the peak. The results of fluorescence dip staining and flowcytometry show that the bacteria in the bacterial solution (30 hours) were mainly living cells, and theSEM images show that the cell sizes of the four bacteria are significantly different. This study also testedthe reproductive characteristics of bacteria under different calcium ion concentrations. The results showthat when the calcium ion concentration is 60 mmol/L, the bacteria can grow well, so biomineral formationis induced at this concentration. In order to analyze the effect of different components in the bacterialsolution on calcium carbonate, the metabolites and cells are separated. The results of ultravioletspectrum, infrared spectrum and hydrogen nuclear magnetic resonance spectrum show that the metabolitesare mainly proteins. The results of SEM and CLSM images show that both cells and metabolites areinvolved in the formation of biominerals, and the bio-calcium carbonate induced by Bacillus pasteurii issmallest, its size is less than 2 lm.

Indoor feeding combined with restricted grazing time improves body health, slaughter performance, and meat quality in Huang-huai sheep

Huang Yafeng,Zhao Mengyu,Zhang Xiaoan,Wei Huiqing,Liu Lumeng,Zhang Zi Jun,Cheng Xiao,Wang Guanjun,Ren Chunhuan 아세아·태평양축산학회 2023 Animal Bioscience Vol.36 No.11

Objective: The aim of this study was to evaluate the effects of three feeding systems, i.e., indoor feeding (CON), indoor feeding with 4-h daily access to grazing artificial pasture (ITGP), and indoor feeding with 8-h daily access to grazing artificial pasture (IEGP), on the plasma antioxidant and immunological capacity, slaughter characteristics, meat quality and economic efficiency of Huang-huai lambs. Methods: Thirty-three healthy Huang-huai rams with similar body weight (approximately 5 mo of age, 28.96±1.01 kg) were assigned equally to three experimental groups. When finished fattening, six lambs from each group were collect blood samples for plasma analyses and then slaughtered to determine slaughter characteristics and obtain biceps brachii muscle for further analysis of meat quality and fatty acid profile. Results: Compared to CON group, animals submitted to ITGP and IEGP groups resulted in greater contents of serum glutathione peroxidase, immunoglobulins (IgA, IgG, and IgM), polyunsaturated fatty acids (PUFA), n-6 PUFA, and PUFA/saturated fatty acid (FA) ratio and lower palmitic /oleic acid ratio (p<0.05). Moreover, animals in ITGP group exhibited a higher (p<0.05) loin eye area, content of meat crude protein (CP), and eicosetrienoic acid compared to CON group, while slaughter performance was superior (p<0.05) to that of the IEGP group. The economic efficiency of ITGP group was 70.12% higher than that of CON group, while the IEGP group exhibited a decrease of 92.54% in economic efficiency compared to the CON group. Conclusion: Restricted grazing time combined with indoor feeding was more effective in conferring superior body health, carcass traits and economic efficiency in Huang-huai lambs, as well as higher CP content and healthier FA composition in the resulting meat.

Feasibility of Three-Dimensional Balanced Steady-State Free Precession Cine Magnetic Resonance Imaging Combined with an Image Denoising Technique to Evaluate Cardiac Function in Children with Repaired Tetralogy of Fallot

Peng YaFeng,Su XinYu,Hu LiWei,Wang Qian,Ouyang RongZhen,Sun AiMin,Guo Chen,Yao XiaoFen,Zhang Yong,Wang LiJia,Zhong YuMin 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.9

Objective: To investigate the feasibility of cine three-dimensional (3D) balanced steady-state free precession (b-SSFP) imaging combined with a non-local means (NLM) algorithm for image denoising in evaluating cardiac function in children with repaired tetralogy of Fallot (rTOF). Materials and Methods: Thirty-five patients with rTOF (mean age, 12 years; range, 7–18 years) were enrolled to undergo cardiac cine image acquisition, including two-dimensional (2D) b-SSFP, 3D b-SSFP, and 3D b-SSFP combined with NLM. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) of the two ventricles were measured and indexed by body surface index. Acquisition time and image quality were recorded and compared among the three imaging sequences. Results: 3D b-SSFP with denoising vs. 2D b-SSFP had high correlation coefficients for EDV, ESV, SV, and EF of the left (0.959– 0.991; p < 0.001) as well as right (0.755–0.965; p < 0.001) ventricular metrics. The image acquisition time ± standard deviation (SD) was 25.1 ± 2.4 seconds for 3D b-SSFP compared with 277.6 ± 0.7 seconds for 2D b-SSFP, indicating a significantly shorter time with the 3D than the 2D sequence (p < 0.001). Image quality score was better with 3D b-SSFP combined with denoising than with 3D b-SSFP (mean ± SD, 3.8 ± 0.6 vs. 3.5 ± 0.6; p = 0.005). Signal-to-noise ratios for blood and myocardium as well as contrast between blood and myocardium were higher for 3D b-SSFP combined with denoising than for 3D b-SSFP (p < 0.05 for all but septal myocardium). Conclusion: The 3D b-SSFP sequence can significantly reduce acquisition time compared to the 2D b-SSFP sequence for cine imaging in the evaluation of ventricular function in children with rTOF, and its quality can be further improved by combining it with an NLM denoising method.