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The Rising Urban Poverty and Political Resentment in a Transitional China: The Experience of Shanghai
Fei Yan
Journal of Politics and Law , 2009, DOI: 10.5539/jpl.v1n1p15
Abstract: Despite China’s economic achievements in the last two decades, the market reforms have also brought about a widening income gap, reduction in social welfare, and rising unemployment. These factors are responsible for the emergence of a large number of urban poor, primarily composed of laid-off workers, unemployment persons, retired labours and urban migrants. As a marginal group, they suffer from economic inadequacy as well as violation of civil rights. Consequently, the urban poor raise a heightened anger with the negative result of the accelerated institutional transition and government’s inability to respond to social problems. Thus conceived, this paper will attempt to (1) analyze the changing mechanisms for the new urban poverty stratum in China; (2) examine the effect of urban poverty on political protest and social upheavals; (3) examine the current policies and its deficits.
Digital Control for Dynamic Performance Enhancement of DC-DC Switching Converters
Yan-Fei Liu
Lecture Notes in Engineering and Computer Science , 2011,
Abstract:
The effects of different sterilization methods on silk fibroin  [PDF]
Yahong Zhao, Xiaoli Yan, Fei Ding, Yumin Yang, Xiaosong Gu
Journal of Biomedical Science and Engineering (JBiSE) , 2011, DOI: 10.4236/jbise.2011.45050
Abstract: The aim of this study was to investigate the changes in the molecular structure and physiological activities of silk fibroin induced by three different sterilization methods (steam, gamma radiation and ethylene oxide) with different dose or time period of sterilization by means of Fourier transform infrared (FT-IR) spec-troscopy, X-ray diffraction, mechanical properties and assessment of molecular weight. The results showed that the steam sterilization darkened the color of silk fibroin and obviously affected the mechanical property; gamma irradiation slightly degraded the molecular weight of silk fibroin and the speed of degradation increased with increasing irradiation dose; and ethylene oxide almost had no influence on silk fibroin expect for some slight hydrolysis on mo-lecular weight. Because ethylene oxide sterilization had the smallest influence on the quality of silk fi-broin with compared to other sterilization methods, it could be used as an efficient method to make fibroin more suitable for the development of functional foods and cosmetics.
Transmittance Measurement of the Nonplanar Optical Based on Focal-Plane-Array Camera  [PDF]
Chengzhi Su, Fei’ou Jiang, Guohua Cao, Yan Zhuang
Engineering (ENG) , 2012, DOI: 10.4236/eng.2012.46037
Abstract: Aiming to solve the problem that it is difficult to accurately measure UV cut-off transmittance of xenon quartz glass by using present spectrophotometer in China SG III project. Through the analysis, we believe that its reason was that the xenon quartz glass was nonplanar so the outgoing beam geometry from under-test was different from that from standard sample. A method of transmittance measurement based on focal-plane-array camera was proposed in this article. The effects of camera uniformity and spot sampling on transmittance measurement were analyzed theoretically. This method, which can reduce the effect of beam geometry on transmittance measurement and eliminate the cutting error occurring during light transmission by monitoring the completeness of incident beam in real-time, is verified from experiments. The random standard uncertainty of this method here is 0.035% or less. It is particularly useful in the transmittance measurement of nonplanar optical.
Effective of Microwave-KOH Pretreatment on Enzymatic Hydrolysis of Bamboo  [PDF]
Zhiqiang Li, Zehui Jiang, Benhua Fei, Yan Yu, Zhiyong Cai
Journal of Sustainable Bioenergy Systems (JSBS) , 2012, DOI: 10.4236/jsbs.2012.24015
Abstract: Bamboo, with its advantages of fast growth, short renovation, easy propagation and rich in cellulose and hemicellulose, is a potential feedstock for bioethanol or other biofuels production. The objective of this study was to examine the feasibility of microwave assistant KOH pretreatments to enhance enzymatic hydrolysis of bamboo. Pretreatment was carried out by immersing the bamboo in KOH (12% and 8% w/w bamboo) solutions and exposing the slurry to microwave radiation power of 400 W for 30min. Chemical composition of the pretreated substrates and spent liquor was analyzed. Pretreated substrates were enzymatic hydrolyzed, and glucose and xylose in the hydrolysate were analyzed. The results showed that the pretreated substrate with microwave assisted KOH had significantly higher sugar yield than the untreated samples. The fermentation inhibitors formic acid, furfural, HMF and levulinic acid were much lower than acid pretreatment reported.
Effect of Online Reviews on Consumer Purchase Behavior  [PDF]
Zan Mo, Yan-Fei Li, Peng Fan
Journal of Service Science and Management (JSSM) , 2015, DOI: 10.4236/jssm.2015.83043
Abstract: In order to understand the effect of online reviews on consumer purchase behavior, more than 400 Taobao shops’ online reviews are collected. Based on S-O-R model (Stimulus-Organism-Response Model), this paper studies the influence on consumer purchase behavior according to online reviews of experience goods from a new perspective of consumer learning. Using SPSS 19.0 software for data analysis and assumptions, statistical results show that the positive reviews, describing rating, picture reviews, appended reviews and cumulative reviews have an effect on consumer purchase behavior. The moderate reviews, negative reviews, logistics rating and service rating are not significant in the results. Finally, this paper puts forward suggestions and summary.
Review on research methods for alelopathy and allelochemicals in plants
植物化感作用(Allelopathy)及其作用物的研究方法

YAN Fei,
阎飞

生态学报 , 2000,
Abstract: Research methods on allelopathy were reviewed.Methods on extraction,separation,purification and etermination of allelochemicals were mainly summarized too.The research issues,on which more attention should be paid in the future,were proposed.
The dynatomic curves for unimodel polynomials are smooth and irreducible
Yan Gao,Ya Fei Ou
Mathematics , 2013,
Abstract: We prove here the smoothness and the irreducibility of the periodic dynatomic curves $ (c,z)\in \C^2$ such that $z$ is $n$-periodic for $z^d+c$, where $d\geq2$. We use the method provided by Xavier Buff and Tan Lei in \cite{BT} where they prove the conclusion for $d=2$. The proof for smoothness is based on elementary calculations on the pushforwards of specific quadratic differentials, following Thurston and Epstein, while the proof for irreducibility is a simplified version of Lau-Schleicher's proof by using elementary arithmetic properties of kneading sequence instead of internal addresses.
Intra-articular injection of xanthan gum: A potential therapy for osteoarthritis  [PDF]
Huarong Shao, Guanying Han, Peixue Ling, Xiqiang Zhu, Fei Liu, Yan Jin, Lijuan Zhao, Tianmin Zhang
Advances in Bioscience and Biotechnology (ABB) , 2012, DOI: 10.4236/abb.2012.324063
Abstract: Osteoarthritis (OA) means inflammation of the joints, with the symptoms of joint pain, stiffness, and swelling of the joints. It is a degenerative disease that appears to be caused by both biomechanical and bio-chemical factors. Intra-articular (IA) injection treatment is one of the main treatment methods for OA because of its positive effect in reducing joint pain and increasing joint mobility. IA injection of xanthan gum (XG) could protect the joint cartilage, relieve the synovitis and reduce the OA progression in experiment OA. The injection of XG may have a long-lasting effect in the joint cavity, which could avoid frequent IA injections. However, for the development of this potential therapy, further studies such as the effective long-term pain relief properties, the detailed action mechanism and the pharmacokinetics of the XG injection will be conducted. This article briefly reviewed the preparation, safety evaluation, pharmacodynamics and possible action mechanism of XG injection, and come up with the ideas for further development of this potential therapy for OA.
The Comparative Study of Vibration Control of Flexible Structure Using Smart Materials
Juntao Fei,Yunmei Fang,Chunyan Yan
Mathematical Problems in Engineering , 2010, DOI: 10.1155/2010/768256
Abstract: Considerable attention has been devoted to active vibration control using intelligent materials as PZT actuators. This paper presents results on active control schemes for vibration suppression of flexible steel cantilever beam with bonded piezoelectric actuators. The PZT patches are surface bonded near the fixed end of flexible steel cantilever beam. The dynamic model of the flexible steel cantilever beam is derived. Active vibration control methods: optimal PID control, strain rate feedback control (SRF), and positive position feedback control (PPF) are investigated and implemented using xPC Target real-time system. Experimental results demonstrate that the SRF and PPF controls have better performance in suppressing the vibration of cantilever steel beam than the optimal PID control. 1. Introduction Actuators from piezoceramic materials have wide application ranging from active vibration control to nanoscale positioning tasks. This is due to their high-frequency response behavior and essentially infinite resolution. Because piezoelectric ceramic materials have mechanical simplicity, small volume, light weight, large useful bandwidth, efficient conversion between electrical energy and mechanical energy, and easy integration with various metallic and composite structures, smart structures with surface-mounted or embedded piezoelectric ceramic patches have received much attention in vibration control of structures in recent years. Within the last two decades, much attention has been focused on active control of structures to suppress their structural vibrations. Active control methods can be used to damp out undesirable structural vibrations. Strain rate feedback (SRF) control is used for active damping of a flexible space structure by Newman [1]. Crawley and de Luis [2] proposed piezoelectric materials to be built in laminated beams. Fanson and Caughey [3] carried out feedback control to suppress structural vibration with segmented piezoelectric actuators and sensors. Positive position feedback (PPF) [4–7] is applied by feeding the structural position coordinate directly to the compensator, and the product of the compensator and a scalar gain positively back to the structure. The model derivation for a vibrating beam is described in many texts. Choi and Lee [8] presented the derivation for the modeling of a beam with a piezoceramic actuator affixed near the base. Many approximate models have been developed to predict the behavior of flexible beams incorporating PZT actuators [9–11]. Adaptive sliding model controller with sliding mode compensator has
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