Influence of Spoke Parameters on Load Capacity of Non-Pneumatic Tires Using Orthogonal Study and Analysis of Variance

Weidong Liu,Changzheng Li,Qiushi Zhang 한국자동차공학회 2024 International journal of automotive technology Vol.25 No.2

This study aims to investigate the relationship between the static characteristics of non-pneumatic tires (NPTs) and spokedesign parameters using the fi nite element (FE) method. A three-dimensional FE model of the NPT was established. Theinfl uence of diff erent ranges of stress and strain on the calculation accuracy of the Neo-Hookean and Yeoh constitutivemodels was analyzed. Subsequently, the main design parameters—spoke thickness, spoke number, and arc curvature—wereselected according to the geometric characteristics of the spokes. The eff ects of these three parameters on the vertical stiff -ness, maximum spoke stress, overall maximum stress, and maximum and average contact pressures were examined usingunivariate and multivariate analysis methods. The range and variance analysis results indicated that the spoke thickness,spoke number, and arc curvature had a signifi cant eff ect on the vertical stiff ness. Finally, the relationship between the verticalstiff ness and product of the spoke thickness and number was obtained using a nonlinear fi tting method. When the arc curvatureof the spoke was less than 5 m −1 , the errors between the calculated and simulated vertical stiff ness did not exceed 5%. This observation can be used to facilitate the rapid design of spoke parameters under diff erent load capacity requirements.

An Adaptively Speculative Execution Strategy Based on Real-Time Resource Awareness in a Multi-Job Heterogeneous Environment

( Qi Liu ),( Weidong Cai ),( Qiang Liu ),( Jian Shen ),( Zhangjie Fu ),( Xiaodong Liu ),( Nigel Linge ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.2

MapReduce (MRV1), a popular programming model, proposed by Google, has been well used to process large datasets in Hadoop, an open source cloud platform. Its new version MapReduce 2.0 (MRV2) developed along with the emerging of Yarn has achieved obvious improvement over MRV1. However, MRV2 suffers from long finishing time on certain types of jobs. Speculative Execution (SE) has been presented as an approach to the problem above by backing up those delayed jobs from low-performance machines to higher ones. In this paper, an adaptive SE strategy (ASE) is presented in Hadoop-2.6.0. Experiment results have depicted that the ASE duplicates tasks according to real-time resources usage among work nodes in a cloud. In addition, the performance of MRV2 is largely improved using the ASE strategy on job execution time and resource consumption, whether in a multi-job environment.

기업의 국제화와 신 정보통신기술의 역할: 중국 Haier 기업을 사례로

Shuguang Liu,Weidong Liu 대한지리학회 2003 대한지리학회지 Vol.38 No.3

신 정보통신기술(ICTs)이 기업의 비즈니스 처리방식을 변화시키고 있다는 점은 일반적으로 받아들여지고 있다. 예를 들어, 기업의 내부자원 관리의 효율성을 제고하기 위한 ERP(enterprise resources planning)와<br/> BPR(business process reengineering) 활용, 공급 연줄망을 통합하기 위한 기업-기업간 e-com의 적용, 그리고 기업-고객간 e-com과 같이 새로운 마켓팅 통로의 창출 등을 들 수 있다. 기업들은 이러한 새로운 방식의 비즈니스가 기업의 생산성 증대 및 개래비용의 절감 효과를 가져온다고 확신한다. 그 결과, 신 ICTs는 다양한 제품을 생산하는 많은 소규모 기업들의 최근 성장과 국제화를 통한 공간적 확산에 중요한 역할을 하고 있다. 본 연구는 중국 Haier 기업을 사례로 기업의 성장과정에 신 ICTs가 끼친 역할을 살펴본 것이다. Haier 기업은 1990년부터 2002년 시기에 초국적 기업으로 성장했는데, 그 배경으로 신 ICTs의 채택과 관련하여 기업의 국제화 과정을 연구한 것이다. 연구결과, Haier 기업의 신 ICTs의 채택은 세계 여러 지역에 위치한 기능체의 통합에 기여했으며, 이는 기업의 국제화에 필수적인 적기생산과 배달체계를 구축함으로써 세계적으로 광범위한 지역의 공급자와 구매자를 가깝게 연계시키는 결과를 가져왔다. 결론적으로 Haier 기업은 신 ICTs를 활용함으로써 10년 이내에 초국적기업으로 성장하게 되었다는 점이다. It is now widely recognized that new Information and Communication Technologies (ICTs) have been changing the way by which firms conduct their businesses. Examples are the application of enterprise resources planning (ERP) and business process reengineering (BPR) to increase the efficiency of internal<br/> resources management, adoption of Business-to-Business e-commerce (B2B e-com) to integrate supply chain, and invention of new marketing channels such as Business-to-Customer (B2C) e-com. These new ways of conducting businesses are believed to help firms to reduce transaction costs and increase productivity. As a result, new ICTs have played an important role in recent growth of many small firms into multi-functional and multi-product corporations and in their spatial expansion towards internationalization as well. This paper takes Haier in China as a case to study the role of new ICTs in the growth of firms and reveal how the new technologies have facilitated the expansion of Haier into a transnational corporation (TNC) by examining the internationalization process of the firm in relation to its adoption of new ICTs in the period from 1990 to 2002. The study reveals that the adoption of new ICTs has helped Haier to integrate its functional units located in dozens of places across the world, which is essential to the internationalization of a firm, and to link closely together its worldwide suppliers and customers to achieve just-in-time (JIT) production and delivery. As such, the<br/> authors of the paper argue that, without the facilitation of new ICTs, Haier could not have developed into a TNC in less than ten years.

NF-${\kappa}B$ activation was involved in reactive oxygen species-mediated apoptosis and autophagy in 1-oxoeudesm-11(13)-eno-$12,8{\alpha}$-lactone-treated human lung cancer cells

Liu, Shanshan,Wu, Di,Li, Lin,Sun, Xiao,Xie, Weidong,Li, Xia 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.8

1-oxoeudesm-11(13)-eno-$12,8{\alpha}$-lactone (OEL), a novel eudesmane-type sesquiterpene compound, has been shown to inhibit the growth of some cancer cell lines and induce significant apoptosis. Here, we investigated the anticancer activities of OEL in human lung cancer cells. Our studies demonstrated that OEL induced both apoptosis and autophagy in A549 and H460 cells. OEL-induced autophagy was assessed by appearance of autophagic vacuoles, formation of acidic vesicular organelles, conversion of LC3-I to LC3-II, recruitment of LC3-II to the autophagosomes, and activation of autophagy genes. Furthermore, administration of autophagic inhibitor 3-methyladenine augments OEL-induced apoptotic cell death. The induction of autophagy and apoptosis by OEL links to NF-${\kappa}B$ activation and the generation of reactive oxygen species (ROS). Interruption of NF-${\kappa}B$ activation by specific inhibitor promotes apoptosis, but decreases autophagy. ROS antioxidants (N-acetylcysteine) attenuated both OEL-induced autophagy and apoptosis. Further experiments confirmed that OEL-induced activation of ROS was increased by NF-${\kappa}B$ inhibitor whereas NF-${\kappa}B$ activation was not affected by ROS inhibition. These findings suggest that OEL-elicited autophagic response plays a protective role that impedes cell death, and inhibition of autophagy could be an adjunctive strategy for enhancing the chemotherapeutic effect of OEL as an antitumor agent.

STUDY ON THE FRACTURE BEHAVIOR OF W-NI-FE HEAVY ALLOYS

WEIDONG SONG,JIANGUO NING,HAIYAN LIU 한국소성가공학회 2008 한국소성가공학회 컨퍼런스 Vol.2008 No.10

Pd (II)-catalyzed vinyl addition polymerization of novel functionalized norbornene bearing dimethyl carboxylate groups

Liu, Binyuan,Li, Yang,Shin, Boo-Gyo,Yoon, Do Yeung,Kim, IL,Zhang, Li,Yan, Weidong Wiley Subscription Services, Inc., A Wiley Company 2007 Journal of polymer science Part A, Polymer chemist Vol.45 No.15

<P>Three novel functionalized polynorbornenes (PNB) with pendant dimethyl carboxylate group (carboxylates—acetate, propionate, and butyrate) are synthesized as a vinyl-type with a palladium (II) catalyst in high yield. The effects of size of substitutents, molar ratio of monomer to catalyst, solvent polarity, reaction time, and temperature on the polymerization of exo-norbornene dimethyl propionate were systematically investigated. The low molar ratio and temperature, as well as high polarity of solvent, and long reaction time, are favorable for the enhancement of the monomer conversion, especially, the solvent have an obvious effect on the catalyst activity. The resulting poly(cis-norbornene-exo-2,3-dimethyl carboxylates) (PNB-dimethyl carboxylates) show good solubility in common organic solvent and high thermal stability up to 360 °C. The glass transition temperature was detected by DMA at 331, 324, and 318 °C for acetate, propionate, and butyrate, respectively. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3391–3399, 2007</P> <B>Graphic Abstract</B> <P>Three novel functionalized PNB-2,3-dimethyl carboxylates (carboxylates—acetate, propionate, butyrate) are synthesized as a vinyl-type with a palladium (II) catalyst in high yield. The resulting PNB-dimethyl carboxylates show good solubility in common organic and high thermal stability up to 360 °C. The glass translation temperature was determined by DMA at 331, 324, and 318 °C for PNB-dimethyl acetate, PNB-dimethyl propionate, and PNB-dimethyl, respectively.</P><P> <img src='wiley_img/0887624X-2007-45-15-POLA22091-gra001.gif' alt='wiley_img/0887624X-2007-45-15-POLA22091-gra001'> </P>

Ring-Opening Polymerization of $\varepsilon$-Caprolactone and Cyclohexene Oxide Initiated by Aluminum $\beta$-Ketoamino Complexes: Steric and Electronic Effect of 3-Position Substituents of the Ligands

Liu, Binyuan,Li, Haiqing,Ha, Chang-Sik,Kim, Il,Yan, Weidong The Polymer Society of Korea 2008 Macromolecular Research Vol.16 No.5

A series of aluminum complexes supported by $\beta$-ketoamino, ligand-bearing, 3-position substituents $LAlEt_2$ ($L=CH_3C(O)C(Cl)=C(CH_3)NAr\;(L_1)$, $L=CH_3C(O)C(H)=C(CH_3)NAr\;(L_2)$, $L=CH_3C(O)C(Ph)=C(CH_3)NAr\;(L_3)$, and $L=CH_3C(O)C(Me)=C(CH_3)NAr\;(L_4)$, $Ar=2,6-^iPr_2C6H_3$) were synthesized in situ and employed in the ring-opening polymerization (ROP) of $\varepsilon$-caprolactone ($\varepsilon$-CL) and cyclohexene oxide (CHO). The 3-position substituents on the $\beta$-ketoamino ligand backbone of the aluminum complexes influenced the catalyst activity remarkably for both ROP of $\varepsilon$-CL and CHO. Aluminum $\beta$-ketoamino complexes displayed different catalytic behavior in ROP of $\varepsilon$-CL and CHO. The order of the catalytic activity of $LAlEt_2$ was $L_1AlEt_2$>$L_2AlEt_2$>$L_3AlEt_2$>$L_4AlEt_2$ for ROP of $\varepsilon$-CL, being opposite to the electron-donating ability of the 3-position substituents on the $\beta$-ketoamino ligand, while the order of the catalytic activity for ROP of CHO was $L_1AlEt_2$>$L_3AlEt_2$>$L_4AlEt_2$>$L_2AlEt_2$. The effects of reaction temperature and time on the ROP were also investigated for both $\varepsilon$-CL and CHO.

Filtration and regeneration behavior of polytetrafluoroethylene membrane for dusty gas treatment

Weidong Zhang,Deqiang Jiang,Junteng Liu,Zhongqi Ren,Wang Geng 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.4

With micron talcum particles and nano-CaCO3 powder as test dust, a series of experiments have been carried out to systematically study the gas filtration and regeneration behavior of polytetrafluoroethylene membrane, and some comparisons were made with common filter media. The experimental results showed that the PTFE membrane had a filtration efficiency of above 99.99% for micron particles, and excellent regeneration behavior was obtained, though a much higher initial pressure drop existed. Based on the results, it was concluded that the PTFE membrane is an excellent surface-filtration media for micron particles. Effects of operation parameters, including airflow velocity, particle concentration and particle characteristics were also investigated. To better understand the evolution of pressure drop during the filtration process, a mathematical model with operation parameters and characteristics of particles was derived from the gas-solid two-phase flow theories. A novel method on the determination of regeneration period of the filter media was put forward based on the analysis of the pressure drop according to this model

Iterative coupling of precise integration FEM and TD-BEM for elastodynamic analysis

Weidong Lei,Chun Liu,Xiaofei Qin,Rui Chen 국제구조공학회 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.67 No.4

The iterative decomposition coupling formulation of the precise integration finite element method (FEM) and the time domain boundary element method (TD-BEM) is presented for elstodynamic problems. In the formulation, the FEM node and the BEM node are not required to be coincident on the common interface between FEM and BEM sub-domains, therefore, the FEM and BEM are independently discretized. The force and displacement converting matrices are used to transfer data between FEM and BEMnodes on the common interface between the FEM and BEM sub-domains, to renew the nodal variables in the process of the iterations for the un-coincident FEM node and BEM node. The iterative coupling formulation for elastodynamics in current paper is of high modeling accuracy, due to the semi-analytical solution incorporated in the precise integration finite element method. The decomposition coupling formulation for elastodynamics is verified by examples of a cantilever bar under a Heaviside-type force and a harmonic load.

Financing Constraints, Principal-Agent and Chinese Listed Firms’ Output Efficiency

Weidong Zhu,Yiling Wang,Jingyu Liu 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.8

It is shown that output under financing constraints and principal-agent can be modeled as a one-side deviation from a frictionless output level. The effects of financing constraints and principal-agent can be identified and quantified by imposing a distribution assumption on the effects. Panel data on Chinese listed firms between 2008 and 2013 are used in the estimation. It is found that: (1) the output efficiency of Chinese listed firms is significantly affected by financing constraints and principal-agent; (2) the severity of financing constraints and principal-agent of firms in different regions varies; (3) firms’ output efficiency in east China varies greatly, and the mean efficiency is the lowest of the three regions.