Improved Convolutional Neural Network for Laser Welding Defect Prediction

Weiwei Huang,Xiangdong Gao,Yuhui Huang,Yanxi Zhang 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.1

In order to predict the laser welding defects, a convolutional neural network prediction model is established. The keyhole image and plume image collected by a high-speed camera are processed to obtain visual information such as keyhole area and plume area. The rolling mean and standard deviation methods are used to calculate the fluctuation degree indicators of the visual information and the optical radiation information obtained by the photoelectric sensor. Finally, three improved one-dimensional convolutional neural network prediction models with a learning rate dynamic adjustment mechanism are established to predict welding defects. Experimental results indicate that the improved one-dimensional convolutional neural network prediction model can avoid premature convergence four times to achieve the best performance. The fluctuation degree indicators of sensor features can distinguish the welding state more easily than the sensor features. The reliability test of the new weld is carried out. The prediction accuracy of fusion detection model of sensor features and fluctuation degree indicators is 99.21%. The improved model can accurately predict laser welding defects.

Static Var Generator Based on Accurate Linearization Combined with Sliding Mode Controller

Liu Fei,Wang Xueyan,Huang Xinyi,Yan Honglin,Huang Xiangdong,Pan Hongguang 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.5

The active and reactive current are hard to be decoupled completely with strong robustness when the traditional proportional integral (PI) algorithm is adopted to feedforward decoupling control for static var generator (SVG). This paper proposed a compound control strategy for SVG based on precise linearization and sliding mode control (SMC). To be specifi c, fi rst, the theory of diff erential geometry is used to prove that the mathematical model of SVG satisfi es the necessary and suffi - cient condition of precise linearization. Second, the precise linearized high-order system of SVG was transformed into two completely independent decoupled fi rst-order linear systems, and realize complete decoupling of active current and reactive current. Finally, SMC was used to design both the voltage outer loop and the current inner loop. Simulations ware carried out for the SVG mathematical model under three conditions which were inductive load, capacitive load and sudden change load. The results of those simulation showed that the controller designed by the proposed control strategy has the advantages of quick reactive power compensation, strong robustness and anti-interference performance.

Synthesis and Application of Polyurethane-Modified Silicone as Finishing Agent for Cotton Fabric

Wenwen Lei,Yufa Sun,Bin Huang,Xiangdong Zhou 한국섬유공학회 2018 Fibers and polymers Vol.19 No.5

The polyurethane modified organic silicone (PU-SA) was successfully synthesized via step-by-step polymerization with isophorone diisocyanate (IPDI) and polypropylene glycol (PPG) used as monomers, dibutyltindilaurate (DBTDL) as the catalyst, trimethylolpropane (TMP) and N-methyldiethanolamine (MDEA) as the chain extender, and amino-terminated siloxane (SA) as the blocking agent. The chemical structure of PU-SA was characterized by Fourier transform infrared spectroscopy (FT-IR). X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) showed that PUSA had been successfully finished on the surface. Additionally, the thermogravimetric analysis (TGA) demonstrated that the PU-SA treated fabrics showed low decomposition temperature and slightly high char residue. As a finishing agent, the effect of PU-SA on the handle of cotton fabrics was also studied by using a Kawabata Evaluation System for Fabrics (KES-F). The experimental results found that PU-SA had a significant improvement on the bending properties, surface properties, and compressional properties. Moreover, the mechanical and anti-wrinkle properties of the cotton fabrics were also enhanced.

중국 호북미술학원 미술기초조형교육의 과제와 방향에 대한 연구

도학회(Do, hakhoe),유향동(Liu, Xiangdong․,Guo, Lan),곽탄,황찬(Huang, Can) 한국미술교육학회 2010 美術敎育論叢 Vol.24 No.3

최근 한국과 중국의 미술교육분야 교류가 활성화되는 시점에서 예술교육을 전문으로 하는 중국 호북성 무한시의 역사 깊은 호북미술학원과 한국의 한국예술종합학교의 기초조형교육을 비교연구 하였다. 연구의 과제는 1학년 기초조형교육과정을 그 범위로 하고, 교육과정과 함께 학생들의 심미의식과 교사들의 교육관도 함께 조사하여 보다 효과적인 비교방법을 모색하였다. 비교결과 호북미술학원의 한국예술종합학교에 비해 교육과정이 단조로웠다. 특히 호북미술학원이 2006년부터 실시한 시각예술기초부의 기초조형교육은 통식교육의 지향, 입시교육의 교정, 예술적 감수성의 향상, 인문학적 접근 등을 목표로 하고 있으나 입체 및 매체교육을 생략함으로서 한국예술종합학교의 파운데이션 과정에 비해 학생들에게 다양한 양식의 미술들을 이해시키고 체험시키는 문화교육적 공간으로서의 미술교육과정으로는 폭이 좁았다. China, in the area of culture tradition, has been considered as the suzerain state of Orient and has long been related with socialistic culture. The Arts Education Society, whichhas recently imported Western culture, has worked with various and new trends of today's Western culture. Today, The educational exchanges between Korea and China have been drastically developed and the many cases of the study on mutual development are needed. The Hubei Art Institution, located in the Mid-China, has 100 years of tradition and is one of the many institutions which have undergone the changes in progress in the arts education of China today. The problems of the standardized education in the existing Korean Universities, art educational institutions as well as in the Hubei art Institution have been pointed out even though they have common features, as in the recently established the Korea National University of Arts in farming of the professional artists in the pre-art educational programs(Foundation Course) and systematic art education programs. Many differences can be found in their goals as well as in the details. The specifics of the education in the Basic Visual Arts Division of the Hubei Arts Institution are in the emphasis on the refinement of the entrance examination, the advancement of artistic sensibility, the exclusion of the three dimensional and the mixed media education. as well as the educational philosophy based on humanistic perspectives. The educational specifics of fundamental level of the Korea National University of Arts are the expansion of the use of visual language; the experience of visual expression in work process; the expansion of reasoning; and the rearing of artists upon educational methods of the Renaissance; the studio-oriented education; the critique and presentation based class methods. The differences seemed to have common goals in the perspectives of esthetics, but many differences can be found in approaching different methods. In the matter of considering the vagueness of the value of arts, the Hubei Arts Institution's basic visual education has relatively a limited curriculum, compared to the Korea National University of Arts, and, as a result, its educational outputs are relatively simple. Gaps can be found in the rapidly changing world of arts education, not only because of the exclusion of the educational process of three dimensional and media, of which the curriculum that the Basic Visual Arts Division once formulated, but also because of the import of the expressing methods in two dimensional education which are limited in the traditional methods. As a result, a number of scholars set up international exchange programs in arts education- expansion of the exchange programs in mixed-media; emphasis on the personal experiences in arts; emphasis on the creative education; classes for all students for the advancement in education as well as for the recovery from the relative weaknesses of the Hubei Arts Institution. This means that the direction of the arts education today is not limited in one area of arts, but it surpass the visual culture education and connects and set the direction to the social phenomenon in general as well as to the communication, which forms spaces for the culture education. These agendas should be studied in the freshmen year when the basic concepts of arts are educated. So, the approach to the elementary level in arts in general should be experienced so that the thought ability of students can be developed in the earliest time. The Hubei Arts Institution has relatively a simple curriculum in the basics of plastic arts education, compared to the Korea National University of Arts. But it is not the writer's intension of judging one school from another by the completeness of a curriculum of one school.

A Nonlinear Model-based Variable Impedance Parameters Control for Position-based Impedance Control System of Hydraulic Drive Unit

Kaixian Ba,Guo-liang Ma,Bin Yu,Zheng-guo Jin,Zhi-peng Huang,Jun-xiao Zhang,Xiangdong Kong 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.7

In this paper, aimed at the problem of control accuracy when the traditional position-based impedance control is applied in the hydraulic drive unit (HDU) of legged robot, a kind of nonlinear model-based variable impedance parameters controller (MVIPC) is designed. First, the mathematical model of position-based impedance control for HDU is given. Second, the performance of traditional position-based impedance control is tested on the HDU performance test platform under different working conditions, and the experimental results show that the control accuracy of this control method needs to be improved greatly. Thirdly, the control idea of MVIPC is described, and the theoretical derivation is deduced. MVIPC considers the high-order dynamic characteristics of servo valve, pressure-flow nonlinearity of servo valve, oil compressibility and load characteristics. Finally, the control performance of MVIPC is verified on the HDU performance test platform. The experimental results show that MVIPC can significantly improve the performance of traditional position-based impedance control, and have an excellent adaptability under different working conditions. This research can provide an underlying control method of hydraulic systems during the robot locomotion.

Systemic Reactions to Dust Mite Subcutaneous Immunotherapy: A 3-Year Follow-up Study

Xiang Dong,Nan Huang,Wenjing Li,Lintao Hu,Xiaolong Wang,Yin Wang,Ning Xiang,Guanghui Liu,Rongfei Zhu 대한천식알레르기학회 2016 Allergy, Asthma & Immunology Research Vol.8 No.5

Purpose: The incidence of allergen specific immunotherapy-related systemic reactions (SRs) varies among different studies, and many factors are likely to contribute to SRs. This study aims to investigate the incidence, characteristics, and risk factors of SRs to standardize dust mite-specific subcutaneous immunotherapy (SCIT) in Central China. Methods: All patients receiving standardized dust mites (100-100,000 SQ-U/mL; Alutard SQ, Hørsholn, Denmark) immunotherapy were followed up. Recorded data included demographics, diagnosis, patient status, pulmonary function testing results before and after each injection, allergen dosage, and details of SRs. Results: From June 2011 to August 2014, a total of 208 patients received 4,369 injections; 27 (13.0%) patients experienced 48 (1.1%) systemic reactions. Most of the SRs were grade 2 reactions (n=30, 62.5%), followed by grade 1 (n=11, 22.9%), grade 3 (n=7, 14.6%), and no fatal reactions occurred. Forty-six SRs (95.8%) occurred within 30 minutes. Higher SR rates were associated with high concentration extracts (100,000 SQ-U/mL), injections with concomitant local reactions (LRs), children, asthma and high sensitivity (skin prick test 3+/4+ and/or sIgE≥17.5 kUA/L) (P<0.05). The estimated odds of SRs increased in children (OR=6.57; 95% CI: 1.88-22.97, P=0.003), asthmatic patients (OR=4.10; 95% CI: 1.72-9.80, P=0.002), and injections with LRs (OR=2.41; 95% CI: 1.33-4.36, P=0.004).Conclusions: The incidence of SRs to dust mite SCIT was low, and multiple factors were associated with the increased incidence of SRs. Children, asthmatics and patients with concomitant LR may be prone to develop SRs.