Facial-Onset Sensory Motor Neuronopathy Syndrome is not Always Facial Onset

Weijun Zhang,Qin Huang,Zhengzheng Xuan,Shibiao Wu,Yuanqi Zhao,Haoyou Xu 대한신경과학회 2020 Journal of Clinical Neurology Vol.16 No.4

Determination of Optimal Build Orientation Based on Satisfactory Degree Theory for RPT

Zhao, Jibin,Liu, Weijun,Wu, Jianhuang Society for Computational Design and Engineering 2006 International Journal of CAD/CAM Vol.6 No.1

In rapid prototyping, the optimal part orientation during fabrication is critical as it can improve part accuracy, minimize the requirement for supports and reduce the production time. Through investigating the geometric issues of STL model and process planning of RPM, This paper establishes optimizing model based on the considerations of staircase effect, support area and production time. The general satisfactory degree function is constructed employing the multi-objective optimization theory based on the general satisfactory degree principle. The best part-building orientation is obtained by solving the function employing generic algorithm. Experiment shows that the methods can effective resolve the part-building orientation in RP.

Effects of Zn Addition on Dynamic Recrystallization of High Strain Rate Rolled Al–Mg Sheets

Lu Zhao,Weijun Xia,Hongge Yan,Jihua Chen,Bin Su 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.5

Effects of Zn addition (0, 0.5, 1.0 and 1.5 wt%) on dynamic recrystallization (DRX) behavior of Al-9.2Mg alloy during highstrain rate rolling (with rolling temperature of 400 °C and strain rate of 8.6 s−1) are carefully investigated. The Zn contentplays a significant role in the enhanced DRX of Al-9.2Mg alloy. The critical strain (εc) and the peak strain (εp) are reducedfrom 0.178 ± 0.002 to 0.102 ± 0.001 and 0.211 ± 0.003 to 0.139 ± 0.002 with the Zn content increasing from 0 to 1.5%,respectively. Almost complete DRX grains are obtained in the Al-9.2Mg-0.5Zn alloy. The DRX volume fraction (FDRX), theaverage DRX grain size (AGS), the volume fraction of high-angle grain boundaries (FHAGBs) and the average grain boundaryangle (θAV) are 91.5%, 5.6 μm, 91.1% and 37.6 º, respectively. The Zn addition can enhance the formation of deformationbands (DBs) and promote the DRX process by providing the nucleation sites for new grains, while the increased dynamicprecipitates inhibit DRX. Continuous dynamic recrystallization (CDRX) is the dominant DRX mechanism, while discontinuousdynamic recrystallization (DDRX) is also existent. Effects of Zn addition on DRX process of the Al–Mg alloys canbe ascribed to the more DBs, the reduced stacking fault energy (SFE) and the dynamic precipitates.

대수층 수리특성 파악을 위한 시추공내 전기전도도측정기법의 현장 시험적용

김지훈,임헌태,Weijun Zhao,김영화,박정빈,심규성,홍정표 대한지질학회 2004 대한지질학회 학술대회 Vol.2004 No.

Effect of Heat Treatment on the Microstructure and Properties of High Strain Rate Rolled 7050 Aluminum Alloy

Yang Liao,Hongge Yan,Weijun Xia,Jihua Chen,Bin Su,Xinyu Li,Lu Zhao 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.4

High strain rate rolling (HSRR) is developed to improve the strength, plasticity and stress corrosion resistance of 7050 aluminumalloy simultaneously. The volume fraction of the small-angle grain boundary in the HSRRed alloy sheet is 89.9%. TEM shows that the presence of dislocations and sub-grains promotes the precipitation of the second phase. The alloy inthe T6 state has the highest strength (622 MPa) and the biggest elongation to rupture (20.6%), but poor corrosion resistance. The over-aged state shows the best corrosion resistance. The RRA state can achieve the tensile strength equivalent to T6 of614 MPa, the highest yield strength of 561 MPa and corrosion resistance comparable to the over-aged state. TEM observationshows the existence of sub-grains and dislocations plays an important role in the nucleation of the second phase. Thehigh strength can be attributed to the higher volume fraction of the precipitates, and the high plasticity can be attributed tothe higher work hardening rate. The better corrosion resistance can be ascribe to the wider precipitate-free zones at the grainboundary and the presence of the larger size second phase particles.

Reflectance estimation for infrared and visible image fusion

( Yan Gu ),( Feng Yang ),( Weijun Zhao ),( Yiliang Guo ),( Chaobo Min ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.8

The desirable result of infrared (IR) and visible (VIS) image fusion should have textural details from VIS images and salient targets from IR images. However, detail information in the dark regions of VIS image has low contrast and blurry edges, resulting in performance degradation in image fusion. To resolve the troubles of fuzzy details in dark regions of VIS image fusion, we have proposed a method of reflectance estimation for IR and VIS image fusion. In order to maintain and enhance details in these dark regions, dark region approximation (DRA) is pro-posed to optimize the Retinex model.With the improved Retinex model based on DRA, quasi-Newton method is adopted to estimate the reflectance of a VIS image. The final fusion out-come is obtained by fusing the DRA-based reflectance of VIS image with IR image. Our method could simultaneously retain the low visibility details in VIS images and the high con-trast targets in IR images. Experiment statistic shows that compared to some advanced ap-proaches, the proposed method has superiority on detail preservation and visual quality.

High-effective generation of H2O2 by oxygen reduction utilizing organic acid anodized graphite felt as cathode

Hongkai Guo,Hu Xu,Chengwen Zhao,Xiangzhong Hao,Ziyuan Yang,Weijun Xu 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.108 No.-

Achieving high catalytic performance with the lowest cost possible cathode material is critical for electrocatalyticsynthesis of H2O2 by oxygen reduction reaction. In this work, we describe a method ofpreparing highly active yet stable graphite felt electrocatalysts containing ultrahigh-loading oxygen contentby using organic acid anodic modification. The results show that modified graphite felt surface wasmore hydrophilic and introduced a large amount of defect sites and oxygen-containing groups. Moreover,the influence of mass oxalic/citric acid ratio and oxidation time of graphite felt cathode were investigated. As a result, H2O2 electrogeneration was 1.6 times as much as that of virgin graphite felt counterpart at themass oxalic/citric acid ratio of 2:1 oxidation for 40 min. However, overoxidation also impaired the electricalproduction of H2O2 due to decarboxylation. Finally, the effect of cathode potential and reaction pHon graphite felt cathode was optimized. As for the modified graphite felt, the maximum accumulationrate of H2O2 reached 4.5 mg h1 cm2 at the conditions of 0.85 V (SCE), 0.4 L min1 O2 flow rate andpH = 3. In addition, it kept a stable performance for electrochemical generation of H2O2 during 8 cycles.

Different divergence events for three pairs of PEBPs in Gossypium as implied by evolutionary analysis

Youjun Lu,Wei Chen,Lanjie Zhao,Jinbo Yao,Yan Li,Weijun Yang,Ziyang Liu,Yongshan Zhang,Jie Sun 한국유전학회 2019 Genes & Genomics Vol.41 No.4

Introduction The phosphatidylethanolamine-binding protein (PEBP) gene family plays a crucial role in seed germination, reproductive transformation, and other important developmental processes in plants, but its distribution in Gossypium genomes or species, evolutionary properties, and the fates of multiple duplicated genes remain unclear. Objectives The primary objectives of this study were to elucidate the distribution and characteristics of PEBP genes in Gossypium, as well as the evolutionary pattern of duplication and deletion, and functional differentiation of PEBPs in plants. Methods Using the PEBP protein sequences in Arabidopsis thaliana as queries, blast alignment was carried out for the identification of PEBP genes in four sequenced cotton species. Using the primers designed according to the PEBP genome sequences, PEBP genes were cloned from 15 representative genomes of Gossypium genus, and the gene structure, CDS sequence, protein sequence and properties were predicted and phylogenetic analysis was performed. Taking PEBP proteins of grape as reference, grouping of orthologous gene, analysis of phylogeny and divergence of PEBPs in nine species were conducted to reconstruct the evolutionary pattern of PEBP genes in plants. Results We identified and cloned 160 PEBPs from 15 cotton species, and the phylogenetic analysis showed that the genes could be classified into the following three subfamilies: MFT-like, FT-like and TFL1-like. There were eight single orthologous group (OG) members in each diploid and 16 double OG members in each tetraploid. An analysis of the expression and selective pressure indicated that expression divergence and strong purification selection within the same OG presented in the PEBP gene family. Conclusion An evolutionary pattern of duplication and deletion of the PEBP family in the evolutionary history of Gossypium was suggested, and three pairs of genes resulted from different whole-genome duplication events.

Effect of Mg Content on the Damping Behavior of Al–Mg Alloys

Zhenzhen Li,Hongge Yan,Jihua Chen,Weijun Xia,Bin Su,Lu Zhao,Min Song 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.9

This article investigated the effect of Mg content (4.5, 6.5 and 9.2, in wt%) on the damping capacities of Al–Mg alloys. The results indicate that the damping behavior can be divided into three regions. Region I refers to the low strain amplituderegion (ε < 5 × 10−5), where the damping capacity decreases with increasing the Mg content and has almost no relation withthe strain amplitude. Region II is the middle strain amplitude region (5 × 10−5 < ε < 8 × 10−4), where the damping capacityincreases rapidly with the strain. Region III refers to the high strain amplitude region (8 × 10−4 < ε < 2 × 10−3), where thedamping capacity remains constant and is independent of the strain when the strain is high enough, but increases with the Mgcontent. The damping values Q−1 of Al–4.5Mg, Al–6.5Mg and Al–9.2Mg alloys are 0.01501 ± 0.00032, 0.01633 ± 0.00032and 0.01862 ± 0.00119 at the strain of 1 × 10−3, respectively. The damping capacity in Region I is mainly determined bythe lattice distortion caused by Mg addition and the restoring force caused by pinning points and Suzuki segregation. Theextended dislocations break away from the pinning effect of Mg atoms and become moveable in Region II, and the movementof extended dislocations is the dominant damping mechanism in Region III.