H7N9 Avian Influenza Emergency Management in China -Temperature and Live Poultry Markets Analysis with Responding Policy Study -

An Chen,YueHua Li,Fei Chi,Zhengquan Yuan 위기관리 이론과 실천 2014 Journal of Safety and Crisis Management Vol.4 No.1

Influenza A virus subtype H7N9 has received great attention since the first human case was reported at the beginning of this year. The viral characteristics have been quickly brought into research process. Here, the effect of temperature and live poultry market has been considered on the basis of analysis of existing data. As expected, both temperature and live poultry market has significant impact on the spread of this epidemic. Finally, the effect of government reactions and medical treatment on response was discussed. It indicated that sufficient and rapid reactions did not always lead to a perfect outcome which proved the influence of temperature and live poultry market potentially. Research highlights: The effect of temperature on H7N9 avian influenza is proved by analyzing the latitude and temperature of affected area. The effect of live poultry markets on H7N9 avian influenza is confirmed by analyzing the relationship between the number of live poultry markets in affected area and incidence of H7N9 human infection. The effect of government actions and medical treatment is studied and it turned out the result is not in accordance with actual efforts.

Behavior and Mechanism of Void Welding Under Thermal Mechanical Coupling

Fei Chen,Xitao Wang,Huiqin Chen,Shue Dang 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

Shrinkage cavity, microporosity, blowhole and the likes are the typical void defects in ingot. Only through reasonable hightemperature deformation and heat preservation process can the void defects be closed and welded to ensure the high qualityof forgings. However, there are few researches on the welding behavior of voids, and the understanding of the void weldingmechanism is still insufficient. In order to further study the welding behavior of void and explore the welding mechanism,the welding process of void and microstructure evolution around void under thermal mechanical coupling were studied byphysical simulation. The results show that heating temperature, holding time, plastic deformation play an important role invoid welding. The void welding degree increases with the increase of heating temperature, holding time and plastic deformation. Besides, there are three main welding mechanisms for void defects, including the volume of microvoids decreasesdue to vacancy diffusion, the void welding mechanism caused by the austenite-ferrite transformation at lower temperaturesand the void welding mechanism caused by recrystallization and grain growth of austenite grains at higher temperatures.

The Study of International Cooperation on Emergencies

An Chen,Jing Rui Chen,Fei Chi 위기관리 이론과 실천 2017 Journal of Safety and Crisis Management Vol.7 No.1

International cooperation on emergencies is significant to the response of these emergencies. Firstly, the connotation and characteristics of international cooperation on emergencies were analyzed. Secondly, the typical types of emergencies in need of international cooperation, the types of countries involved in international cooperation and the typical types of international cooperation modes on emergencies were analyzed in order to explain the mechanism of international cooperation. Finally, some strategies of international cooperation on emergencies were proposed. The result shows that, in order to have a better international cooperation, international cooperation modes on emergencies should be determined according to the types of emergencies, the situations of countries and organizations involved in it.

Preparation and Properties of Y₂O₃-Doped ZrO₂ Films on Etched Al Foil by Sol-Gel Process

Chen, Fei,Park, Sang-Shik Materials Research Society of Korea 2015 한국재료학회지 Vol.25 No.2

The oxide films formed on etched aluminum foils play an important role as dielectric layers in aluminum electrolytic capacitors. $Y_2O_3$-doped $ZrO_2$ (YZ) films were coated on the etched aluminum foils by sol-gel dip coating, and the electrical properties of YZ-coated Al foils were characterized. YZ films annealed at $450^{\circ}C$ were crystallized into a cubic phase, and as the $Y_2O_3$ doping content increased, the unit cell of $ZrO_2$ expanded and the grain size decreased. The etch pits of Al foils were filled by YZ sol when it dried at atmospheric pressure after repeating for several times, but this step could essentially be avoided when being dried in a vacuum. YZ-coated foils indicated that the specific capacitance and dissipation factor were $2-2.5{\mu}F/cm^2$ and 2-4 at 1 kHz, respectively, and the leakage current and withstanding voltage of films approximately 200 nm thick were $5{\times}10^{-4}A$ at 21 V and 22 V, respectively. After being anodized at 500 V, the foils exhibited a specific capacitance and dissipation factor of $0.6-0.7{\mu}F/cm^2$ and 0.1-0.2, respectively, at 1 kHz, while the leakage current and withstanding voltage were $2{\times}10^{-4}-3{\times}10^{-5}A$ at 400 V and 420-450 V, respectively. This suggests that YZ film is a promising dielectric that can be used in high voltage Al electrolytic capacitors.

Gratitude to Other’s Support and the Intent to Purchase the Other-gift

CHEN, FEI(진비),ZHENYAO LIAO(료진요),Nak Hwan Choi(최낙환) 한국산업경제학회 2021 산업경제연구 Vol.34 No.1

이 연구는 타인의 도움에 대한 감사가 타인의 선물구매의도에 미치는 영향에서 답례적 타인선물 동기와 타인선물구매에서 느끼는 기쁨의 매개역할의 탐색에 목적을 두었다. 과거 연구들을 탐색하여 가설을 개발하고 설문지를 작성하여 배포하고 279부의 회수된 설문지 자료로 가설을 검증하고, 다음의 결과를 도출하였다. 첫째, 타인의 도움에 대한 감사가 답례적 타인선물 동기와 타인선물의 구매를 위한 지출에서 느끼는 기쁨에 긍정적인 영향을 주었다. 둘째, 답례적 타인선물 동기가 타인선물을 위한 구매지출에서 느끼는 기쁨에 긍정적인 영향을 주었다. 셋째, 그 기쁨이 타인의 선물구매의도에 긍정적인영향을 주었다. 마케터는 타인의 도움에 대한 감사에 초점을 두고 답례적 선물동기와 선물구매지출에서 느끼는 기쁨을 유도할 수 있는 방안에 주의해야 한다. This article aimed at examining the mediation role of reciprocal other-gift motivation and pleasure in spending for other-gift in the effect of gratitude to other’s support on the intent to purchase the other-gift. 279 questionnaire data used to verify hypotheses showed the following results. First, consumers’ gratitude to other’s support positively influences on the reciprocal other-gift motivation, the pleasure in spending for the other-gift and the intent to purchase the other-gift. Second, the reciprocal other-gift motivation has positive effect on the pleasure in spending for the other-gift. Third, the pleasure in spending for other-gift positively influences on the intent to purchase the other-gift. Marketers should give attention to inducing the reciprocal motivation and the pleasure in purchasing their products as the other-gift by focusing on the consumer’s gratitude towards other’s support.

Dimensional Synthesis of Antenna-Deployable Support Structure

Fei Lin,Chuanzhi Chen,Jinbao Chen,Meng Chen 한국항공우주학회 2020 International Journal of Aeronautical and Space Sc Vol.21 No.2

To improve the deployment stability and drive efficiency, the dimensional synthesis of antenna deployable support structure is addressed. First, to evaluate the deployment stability, the transmission ratio stability index (TRSI) is designed based on Jacobian matrix. Second, the motion/force transmissibility is used to analyse the drive efficiency. A sub-closed-loop analysis method (SAM) is proposed to analyse the local motion/force transmissibility of the parallel mechanism whose sub-closed-loop contains actuator (PMSCA). An improved global transmission index (IGTI) is proposed to analyse the global motion/force transmissibility for the mechanism without good transmission workspace (GTW). Finally, based on TRSI and IGTI, the dimensional parameter optimization model of the deployable support structure is established and a configuration with better comprehensive performance is obtained. Results show that the designed indexes in this paper can be useful for indicating the stability of transmission ratio and the global motion/force transmissibility of the structure.

Effect of second phase particles on the corrosion resistance of magnesium alloy plasma electrolytic oxidation (PEO) coatings in acidic corrosive media

Fei Chen,Zhiwei Rong 한국표면공학회 2023 한국표면공학회 학술발표회 초록집 Vol.2023 No.11-1

Physically-Based Constitutive Modelling of As-Cast CL70 Steel for Hot Deformation

Fei Chen,Xiaodong Zhao,Jinyu Ren,Huiqin Chen,Xiaofeng Zhang 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.6

In order to conduct numerical simulation of plasticity forming and confirm the processing parameters of heat deformationfor as-cast CL70 steel, the hot deformation behaviors of as-cast CL70 steel were studied by isothermal compression testswhich used a Gleeble-1500D thermal mechanical simulation tester for the deformation temperatures ranging from 1173 to1523 K and the strain rates ranging from 0.001 to 1 s−1. Flow stress curves of the steel were obtained under high temperature. The flow stress constitutive models of the work hardening-dynamical recovery period and dynamical recrystallizationperiod were established for as-cast CL70 steel. In work hardening-dynamic recovery period, the flow stress was predicted byemploying the evolution rule of dislocation density in the constitutive model. In dynamic recrystallization period, the flowstress after the critical strain was predicted by employing the dynamic recrystallization kinetics in the constitutive model. To improve the prediction accuracy of the model, the dynamic recovery coefficient is modified in the traditional physicallybasedconstitutive model. The results indicate that the proposed physically-based constitutive model has high accuracy inpredicting the flow stress under hot deformation for as-cast CL70 steel.

Large local lattice expansion in graphene adlayers grown on copper

Chen, Chaoyu,Avila, José,Arezki, Hakim,Nguyen, Van Luan,Shen, Jiahong,Mucha-Kruczyń,ski, Marcin,Yao, Fei,Boutchich, Mohamed,Chen, Yue,Lee, Young Hee,Asensio, Maria C. Nature Publishing Group UK 2018 NATURE MATERIALS Vol.17 No.5

<P>Variations of the lattice parameter can significantly change the properties of a material, and, in particular, its electronic behaviour. In the case of graphene, however, variations of the lattice constant with respect to graphite have been limited to less than 2.5% due to its well-established high in-plane stiffness. Here, through systematic electronic and lattice structure studies, we report regions where the lattice constant of graphene monolayers grown on copper by chemical vapour deposition increases up to similar to 7.5% of its relaxed value. Density functional theory calculations confirm that this expanded phase is energetically metastable and driven by the enhanced interaction between the substrate and the graphene adlayer. We also prove that this phase possesses distinctive chemical and electronic properties. The inherent phase complexity of graphene grown on copper foils revealed in this study may inspire the investigation of possible metastable phases in other seemingly simple heterostructure systems.</P>

Synthesis and Cell Death Mechanism of a Militarin Derivative

Fei Chen,Deok Hyo Yoon,Dinneswara Reddy,Changwoo Han,최성아,조재열,성기호,황기철,김태웅,박해일 대한화학회 2016 Bulletin of the Korean Chemical Society Vol.37 No.3

Militarin, a novel anticancer substance from a caterpillar-grown traditional insect-flower (Cordyceps militaris), was previously isolated and characterized as an ether compound of 4-tert-octylphenol and a nonaethylene glycol. Among militarin analogs with different numbers of ethylene glycol substructure, the analog with four ethylene glycol substructure (M4EG) exhibited potent anticancer activities. A facile and scalable synthetic pathway of the M4EG was developed and the mechanism of cell death by the M4EG against lung adenocarcinoma epithelial cell line (A549) was explored. The results of this study showed that apoptosis of M4EG toward A549 cells is mediated by a caspase-dependent death-signaling pathway.