An experimental research for the dynamic characteristic of air spring under the design load

Guo Feng,Jongwon Seok 대한기계학회 2018 대한기계학회 춘추학술대회 Vol.2018 No.5

Existence and multiplicity of solutions for Kirchhoff-Schr\"{o}dinger-Poisson system with concave and convex nonlinearities

Guofeng Che,Haibo Chen 대한수학회 2020 대한수학회지 Vol.57 No.6

This paper is concerned with the following Kirchhoff-Schr\"{o}d\-inger-Poisson system $$ \scalebox{0.84}{$\displaystyle\left\{\!\! \begin{array}{ll} \displaystyle -\big(a+b\int_{\mathbb{R}^{3}}|\nabla u|^{2}\mathrm{d}x\big)\Delta u + V(x)u+\mu\phi u=\lambda f(x)|u|^{p-2}u+g(x)|u|^{q-2}u, &\mbox{ in }\mathbb{R}^{3},\\ -\Delta \phi= \mu |u|^{2}, &\mbox{ in }\mathbb{R}^{3},\\ \end{array} \right.$} $$ where $a>0,~b,~\mu\geq0$, $p\in(1,2)$, $q\in[4,6)$ and $\lambda>0$ is a parameter. Under some suitable assumptions on $V(x)$, $f(x)$ and $g(x)$, we prove that the above system has at least two different nontrivial solutions via the Ekeland's variational principle and the Mountain Pass Theorem in critical point theory. Some recent results from the literature are improved and extended.

Tool wear prediction considering uncovered data based on partial least square regression

Guofeng Wang,Zhiwei Guo,Lei Qian 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.1

Tool wear prediction plays an important role in guaranteeing the workpiece quality and improving the production efficiency. However,because of the uncertainty and complexity of tool wear process, it is hard to ensure that the samples related to all tool wear values can becollected during the training stage. Therefore, the accuracy of tool wear prediction for these uncovered data will deteriorate severely. Inthis paper, partial least square regression is presented to realize the tool wear prediction based on force signal. The main characteristic ofthis method is that the regression analysis is in the principal component space so that the multicollinearity between explanatory variablescan be avoided effectively. Side milling experiment was carried out to validate the effectiveness of the proposed model. The analysis andcomparison under different number of uncovered data show that the partial least square regression based tool wear prediction is moreaccurate.

An improved dynamic milling force coefficients identification method considering edge force

Guofeng Wang,Dongbiao Peng,Xuda Qin,Yinhu Cui 대한기계학회 2012 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.26 No.5

"The identification of the dynamic coefficients is the key to realize accurate simulation of dynamic milling process. To enlarge the scope of dynamic simulation without ignoring edge force, an improved method is presented to calculate milling force coefficients. In this method, linear approximation of average milling force is integrated with multiple linear regressions by supposing that milling force coefficients are time invariant for small variation of feed rate. Therefore, both the shear coefficients and the edge coefficients can be calculated simultaneously. A comparison of simulated milling force with and without the edge force is illustrated and the result shows that the accuracy is higher if the edge force coefficients are considered. This method casts new light on fast and accurate simulation of the dynamic milling force in real industrial environment."

Slurry development for the deposition of a GdSiO4+Mullite environmental barrier coating on silicon carbide

Guofeng Chen,Kang N Lee,Surendra N Tewari 한양대학교 세라믹연구소 2007 Journal of Ceramic Processing Research Vol.8 No.2

In this paper, the preparation of a GdSiO4+Mullite coating by a slurry dip process is described. The slurry was optimized in terms of solid loading, solvent type and the chemical as dispersant and/or binder, and the process was determined based on the surface quality by SEM examination. The results showed that a slurry using ethanol as solvent, polyvinyl butyral (PVB) as both dispersant and binder together with a relatively high ceramic loading contributed to the successful deposition of a GdSiO4+Mullite coating on SiC. In this paper, the preparation of a GdSiO4+Mullite coating by a slurry dip process is described. The slurry was optimized in terms of solid loading, solvent type and the chemical as dispersant and/or binder, and the process was determined based on the surface quality by SEM examination. The results showed that a slurry using ethanol as solvent, polyvinyl butyral (PVB) as both dispersant and binder together with a relatively high ceramic loading contributed to the successful deposition of a GdSiO4+Mullite coating on SiC.

AN EMPIRICAL STUDY ON CONSUMER PURCHASE INTENTION AND IWOM BASED ON TAM

Guofeng Li 글로벌지식마케팅경영학회 2014 Global Marketing Conference Vol.2014 No.11

The online word-of-mouth exert an growing influence on consumers, but how Internet word of mouth influences consumers' attitude and the purchase intention, this problem and its mechanism of action has not been fully researched yet. In this paper, the theory of word-of-mouth and the results of the existing system are proposed, and it contains three independent variables which influence the spread of word-of-mouth effects: the intensity of relationship, perceiving risk and the profession of transmitter. Moreover, an investigate was acted in the college students, the data was disposed with SPSS16.0 to describe statistical analysis and fitting degree evaluation. Based on the analysis of data, the customer relationship management. Suggestions and corresponding analysis are put forward.

Research on WebGIS-Based Stadium Intelligent Service System

Guofeng-WU,Zhishuang-Li 보안공학연구지원센터 2016 International Journal of Grid and Distributed Comp Vol.9 No.12

Centered on the WebGIS technology of J2EE and combined with the distributed GIS special database, this paper researches on the WebGIS-based stadium intelligent service system. Through deep research of multiple traditional optimal path algorithms, improved algorithm is worked out. Then, after in-depth analyses of users’travel modes, this paper finally devises the optimal path of accessibility of stadiums which can be realized in the WebGIS-based stadium service system. The results show that this optimal path design makes it easier for users to check real-time stadiums and helps users achieve the most accurate information about stadiums, hotels, which provides convenience for users to make the best decisions and improves the efficiency of urban transport. Taking full advantage of mobile Internet and GPS technology, this design lays a foundation for the construction of smart city.

L-Leucine increases the daily body temperature and affords thermotolerance in broiler chicks

Guofeng Han,Hui Yang,Yunhao Wang,Shogo Haraguchi,Takuro Miyazaki,Takashi Bungo,Kosuke Tashiro,Mitsuhiro Furuse,Vishwajit S. Chowdhury 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.6

Objective: Heat stress poses an increasing threat for poultry production. Some amino acids have been found to play critical roles in affording thermotolerance. Recently, it was found that in ovo administration of L-leucine (L-Leu) altered amino acid metabolism and afforded thermotolerance in heat-exposed broiler chicks. Methods: In this study, two doses (35 and 70 μmol/egg) of L-Leu were administered in ovo on embryonic day 7 to determine their effect on rectal temperature (RT), body weight (BW) and thyroid hormones at hatching. Changes in RT, BW, and thermotolerance in post-hatched chicks were also analyzed. Results: It was found that in ovo administration of L-Leu dose-dependently reduced RT and plasma thyroxine (T4) level just after hatching. In post-hatched neonatal broiler chicks, however, the higher dose of L-Leu administered in ovo significantly increased RT without affecting BW gain. In chicks that had been exposed to heat stress, the RT was significantly lowered by in ovo administration of L-Leu (high dose) in comparison with the control chicks under the same high ambient temperature (HT: 35°C±1°C, 120 min). Conclusion: In ovo administration of L-Leu in a high dose contributed to an increased daily body temperature and afforded thermotolerance under HT in neonatal broiler chicks.

The Impact of the Regional Comprehensive Economic Partnership (RCEP) on Intra-Industry Trade: An Empirical Analysis Using a Panel Vector Autoregressive Model

Guofeng Zhao,문철주 한국무역학회 2023 Journal of Korea trade Vol.27 No.3

Purpose – This study aims to examine the dynamic relationship between the variables impacted by the Regional Comprehensive Economic Partnership (RCEP) and the level of intra-industry trade among member states, with the ultimate objective of deducing the short- and long-term effects of RCEP on trade. Design/methodology – This study focuses on tariffs, GDP growth rates, and the proportion of regional FDI to total FDI as research variables, and employs a panel vector autoregression model and GMMstyle estimator to investigate the dynamic relationship between RCEP and intra-industry trade among member countries. Findings – The study finds that the level of intra-industry trade between member states is positively impacted by both tariffs and intra-regional FDI. The impulse response graph shows that tariffs and FDI within the region can promote intra-industry trade among member countries, with a quick response. However, the contribution rates of tariffs and intra-regional FDI are not particularly high at approximately 1.5% and 1.4%, respectively. In contrast, the contribution rate of GDP growth can reach around 8.5%. This implies that the influence of economic growth rate on intra-regional trade in industries is not only long-term but also more powerful than that of tariffs and intra-regional FDI. Originality/value – The originality of this study lies in providing a new approach to investigating the potential impact of RCEP while avoiding the limitations associated with the GTAP model. Additionally, this study addresses existing gaps within the research, further contributing to the research merit of the study

Design and Analysis of Lorentz Force-type Magnetic Bearing Based on High Precision and Low Power Consumption

Guofeng Xu,Yuanwen Cai,Yuan Ren,Chaojun Xin,Yahong Fan,Dengliang Hu 한국자기학회 2017 Journal of Magnetics Vol.22 No.2

Magnetically suspended control & sensitive gyroscope (MSCSG) is a novel type of gyroscope with the integration of attitude control and attitude angular measurement. To improve the precision and reduce the power consumption of Lorentz Force-type Magnetic Bearing (LFMB), the air gap flux density distribution of LFMB has been studied. The uniformity of air gap flux density is defined to qualify the uniform degree of the air gap flux density distribution. Considering the consumption, the average value of flux density is defined as well. Some optimal designs and analyses of LFMB are carried out by finite element simulation. The strength of the permanent magnet is taken into consideration during the machining process. To verify the design and simulation, a high-precision instrument is employed to measure the 3-dimensional magnetic flux density of LFMB. After measurement and calculation, the uniform degree of magnetic flux density distribution reaches 0.978 and the average value of the flux density is 0.482T. Experimental results show that the optimal design is effective and some useful advice can be obtained for further research.