Effect of Hot-forging on NiTi Shape Memory Alloy Fibers Reinforced Mg Alloy Composite

Guo Qi,Li Gang,Tang Renjian,Yan Biao 한국분말야금학회 2006 한국분말야금학회 학술대회논문집 Vol.2006 No.1

The composite used in this paper was prepared by hot-pressing ball-milled Mg alloy powders, in which NiTi shape memory alloy fibers in a row were sandwiched. The microstructure and property were examined. It is shown that the composite consisted of a homogenous matrix with uniformly distributed NiTi shape memory alloy fibers, recrystallization took place in the Mg alloy matrix which was subjected to plastic deformation an adequate bonding formed between the matrix and fibers; the density and tensile strength of the composite increased after the hot-forging; the hot-forging process is capable of improving properties of the composite.

How to organically integrate moral education and art curriculum in schools

Guo Qi 동방문화대학원대학교 문화예술콘텐츠연구소 2021 문화와예술연구 Vol.17 No.-

“도덕교육은 학생과 가깝고 직업과 가까우며 사회와 가까운 실천을 중시해야 한다.” 그래서 직업학교의 도덕교육은 학생의 인지능력과 전공특징에 따라 과감하게 혁신적인 교육 디자인을 하고, 예술교육의 내용과 형식을 차용해야 한다. 그 형상성으로 도덕교육을 그 모습을 생생하고 생동감 있게 만들어야 한다. 학생들의 감정적 공감을 불러일으키고 교육 효과를 향상시키며 학생의 종합적인 자질을 향상시켜야 한다. 그러므로 도덕교육은 그 과목의 기본적 문제를 핵심으로 삼고 학생들이 관련 지식을 배우는 것부터 시작함으로써 삶에 뿌리를 두어야 한다. 학생들이 삶을 관찰하고, 삶을 느끼고, 삶을 경험하는 과정에서 긍정적인 삶의 태도를 형성하여 도덕교육의 ‘지식, 감정, 의도, 믿음, 그리고 실천’의 통합을 실현할 수 있도록 해야 한다. "Moral education should be close to students, to the profession, and to the Society and pay attention to the practice". Therefore, according to the cognitive ability and professional characteristics of students, the moral education in vocational schools should boldly innovate teaching design, and use its figure to make moral education vividly and lively depending on the content and form of art education. It can inspire students with emotional resonance, improve teaching effects and enhance the comprehensive quality of students. Therefore, the moral education shall be rooted in life, by taking the basic problems of the subject as the core, and starting with students learning relevant knowledges. So that students can form a positive attitude towards life in the process of observing life, feeling life and experiencing life, so as to realize the unity of "knowledge, emotion, intention, faith and practice" of moral education.

Carnosic acid protects against acetaminophen-induced hepatotoxicity by potentiating Nrf2-mediated antioxidant capacity in mice

Guo, Qi,Shen, Zhiyang,Yu, Hongxia,Lu, Gaofeng,Yu, Yong,Liu, Xia,Zheng, Pengyuan The Korean Society of Pharmacology 2016 The Korean Journal of Physiology & Pharmacology Vol.20 No.1

Acetaminophen (APAP) overdose is one of the most common causes of acute liver failure. The study aimed to investigate the protective effect of carnosic acid (CA) on APAP-induced acute hepatotoxicity and its underlying mechanism in mice. To induce hepatotoxicity, APAP solution (400 mg/kg) was administered into mice by intraperitoneal injection. Histological analysis revealed that CA treatment significantly ameliorated APAP-induced hepatic necrosis. The levels of both alanine aminotransferase (ALT) and aspartate transaminase (AST) in serum were reduced by CA treatment. Moreover, CA treatment significantly inhibited APAP-induced hepatocytes necrosis and lactate dehydrogenase (LDH) releasing. Western blot analysis showed that CA abrogated APAP-induced cleaved caspase-3, Bax and phosphorylated JNK protein expression. Further results showed that CA treatment markedly inhibited APAP-induced pro-inflammatory cytokines TNF-${\alpha}$, IL-$1{\beta}$, IL-6 and MCP-1 mRNA expression and the levels of phosphorylated $I{\kappa}B{\alpha}$ and p65 protein in the liver. In addition, CA treatment reduced APAP- induced hepatic malondialdehyde (MDA) contents and reactive oxygen species (ROS) accumulation. Conversely, hepatic glutathione (GSH) level was increased by administration of CA in APAP-treated mice. Mechanistically, CA facilitated Nrf2 translocation into nuclear through blocking the interaction between Nrf2 and Keap1, which, in turn, upregulated anti-oxidant genes mRNA expression. Taken together, our results indicate that CA facilitates Nrf2 nuclear translocation, causing induction of Nrf2-dependent genes, which contributes to protection from acetaminophen hepatotoxicity.

Short-Term Prediction of Disturbance Inputs of the Greenhouse System

Guoqi Ma,Linlin Qin,Xinghua Liu,Chun Shi,Gang Wu 제어로봇시스템학회 2015 제어로봇시스템학회 국제학술대회 논문집 Vol.2015 No.10

Greenhouse microclimate control system is a typical hybrid system, in which the discrete (or logical) variables and continuous variables interact. The existence of outside measurable but uncontrollable disturbance inputs including outside temperature, humidity, wind speed, solar radiation, and et al, makes the control problem of greenhouse microclimate a challenging one and some conventional control methods not applicable, which motivates us to investigate the prediction problem of disturbance inputs of greenhouse control system. First, grey prediction model GM (1, 1) and time series model ARIMA (p, d, q) are adopted to predict the outside humidity over the next four hours, respectively. Then, considering the nonstationary property of the humidity sequence, wavelet analysis theory is applied to decompose the humidity sequence into different scales in order to reduce the randomness of the original sequence. Furthermore, the low frequency signal and high frequency one are predicted by GM (1, 1) and time series model ARIMA (p, d, q), respectively. Finally, simulation studies are carried out to compare the three prediction methods.

Approximate Bisimulations for Constrained Discrete-Time Linear Systems

Guoqi Ma,Linlin Qin,Xinghua Liu,Chun Shi,Gang Wu 제어로봇시스템학회 2015 제어로봇시스템학회 국제학술대회 논문집 Vol.2015 No.10

In this paper, we consider the problem of approximate bisimulations for constrained discrete-time linear systems. First, we develop a theory of approximation for transition systems with nondeterministic evolution. Then observation metrics are used to describe the bounded distance between system observations. Furthermore, we utilize a class of Lyapunov-like functions, called bisimulation functions, to characterize the approximate bisimulation relations. For the class of discrete-time linear systems with constrained inputs, we convert the problem of computing bisimulation functions to linear matrix inequalities (LMIs) and optimization problems. Finally, a numerical example is performed to verify the effectiveness of the approximation bisimulation framework design technique, and using multi-parametric toolbox (MPT), we also demonstrate the application to safety verification.

Set-membership Estimation for Event-triggered 2-D Systems Based on Zonotopes

Xudong Wang,Guoqi Wang,Liu Yang,Jitao Li 제어·로봇·시스템학회 2024 International Journal of Control, Automation, and Vol.22 No.3

This article discusses the interval estimation for 2-D systems in Roesser model with amplitude-boundedenvironmental disturbance and measurement noise. To save the limited capacity of communication network, anevent-triggered communication strategy is adopted to reduce the amount of packets transmitted through the network. Considering the amplitude-bounded uncertainties, an observer design criterion with peak-to-peak norm boundis deduced to suppress the influence of uncertainties on estimation error. A zonotope-based interval estimation approach is derived such that the actual state of 2-D Roesser system is enclosed within the estimated intervals on thebasis of the obtained observer. Finally, a numerical example is presented to verify the effectiveness of the proposedalgorithm

Terminal sliding mode control of master-slave system with Markovian jump parameters

Xinghua Liu,Guoqi Ma,Hongsheng Xi,Weidong Wang 제어로봇시스템학회 2015 제어로봇시스템학회 국제학술대회 논문집 Vol.2015 No.10

The finite-time synchronization of master-slave system with Markovian jump parameters is investigated in this paper. An equivalent control based terminal sliding mode control is proposed to guarantee the finite-time convergence of error dynamics. By using stochastic theory and Lyapunov method, some conditions are proposed to facilitate the sliding surface design. Furthermore, a desired controller is synthesized to ensure that the trajectory of the closed-loop error system can be driven onto the prescribed sliding mode surface. Finally numerical simulations are presented to illustrate the effectiveness of terminal sliding mode control scheme.

Boundary-compensated Lesion Aware Transformer for Polyp Segmentation

Yuan Ju,Bingxin Wei,Guoqi Liu,Haewoon Nam 한국통신학회 2023 한국통신학회 학술대회논문집 Vol.2023 No.2

Mutation of Cellulose Synthase Gene Improves the Nutritive Value of Rice Straw

Su, Yanjing,Zhao, Guoqi,Wei, Zhenwu,Yan, Changjie,Liu, Sujiao Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.6

Rice straw is an important roughage resource for ruminants in many rice-producing countries. In this study, a rice brittle mutant (BM, mutation in OsCesA4, encoding cellulose synthase) and its wild type (WT) were employed to investigate the effects of a cellulose synthase gene mutation on rice straw morphological fractions, chemical composition, stem histological structure and in situ digestibility. The morphological fractions investigation showed that BM had a higher leaf sheath proportion (43.70% vs 38.21%, p<0.01) and a lower leaf blade proportion (25.21% vs 32.14%, p<0.01) than WT. Chemical composition analysis showed that BM rice straw was significantly (p<0.01) higher in CP (crude protein), hemicellulose and acid insoluble ash (AIA) contents, but lower in dry matter (DM), acid detergent fiber (ADFom) and cellulose contents when compared to WT. No significant difference (p>0.05) was detected in neutral detergent fiber (NDFom) and ADL contents for both strains. Histological structure observation indicated that BM stems had fewer sclerenchyma cells and a thinner sclerenchyma cell wall than WT. The results of in situ digestion showed that BM had higher DM, NDFom, cellulose and hemicellulose disappearance at 24 or 48 h of incubation (p<0.05). The effective digestibility of BM rice straw DM and NDFom was greater than that of WT (31.4% vs 26.7% for DM, 29.1% vs 24.3% for NDFom, p<0.05), but the rate of digestion of the slowly digested fraction of BM rice straw DM and NDF was decreased. These results indicated that the mutation in the cellulose synthase gene could improve the nutritive value of rice straw for ruminants.

Allocating Minimum Number of Leaders for Seeking Consensus over Directed Networks with Time-varying Nonlinear Multi-agents

Leitao Gao,Guangshe Zhao,Guoqi Li,Yuming Liu,Jiangshuai Huang,Changyun Wen 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.1

In this paper, we consider how to determine the minimum number of leaders with allocation and how toachieve consensus over directed networks consisting of time-varying nonlinear multi-agents. Firstly, the problemof finding minimum number of leaders is formulated as a minimum spanning forest problem, i.e., finding theminimum population of trees in the network. By introducing a toll station connecting with each agent, this problemis converted to a minimum spanning tree problem. In this way, the minimum number of leaders is determined andthese leaders are found locating at the roots of each tree in the obtained spanning forest. Secondly, we describe avirtual leader connected with the allocated leaders, which indicates that the number of edges connected the followeragents with the virtual leader is the least in an arbitrary directed network. This method is different from the existingconsensus problem of redundant leaders or edges that connect the follower with one leader in special networks. A distributed consensus protocol is revisited for achieving final global consensus of all agents. It is theoreticallyshown that such a protocol indeed ensures consensus. Simulation examples in real-life networks are also providedto show the effectiveness of the proposed methodology. Our works enable studying and extending application ofconsensus problems in various complex networks.