TIME-VARYING COEFFICIENT TAYLOR RULE AND CHINESE MONETARY POLICY: EVIDENCE FROM THE TIME-VARYING COINTEGRATION

YU GUO,Wei Ma 중앙대학교 경제연구소 2016 Journal of Economic Development Vol.41 No.4

No consensus has been reached about whether the Taylor rule performs well in China. Most studies have either ignored the nonstationarity of the variables in the Taylor rule model or assumed a constant cointegrating vector. China is a transition economy, undergoing gradual reform. Consequently, the fixed coefficient cointegration approach is unable to capture the long-run relationship among interest rate, inflation gap, and output gap. Therefore, this paper develops a time-varying coefficient Taylor rule and estimates it using a smooth time-varying cointegrating approach. The results show a time-varying long-run relationship among the variables in the Taylor rule. The coefficient on the inflation gap is significantly less than 1, indicating that the nominal interest rate’s response to inflation is inadequate. Moreover, the coefficient on the output gap is significantly greater than 0, implying that the response of the nominal interest rate to the output gap is sensitive. The People’s Bank of China should adjust the short-term interest rate should be more flexible especially to changes in inflation.

A mechanical model of vehicle-slab track coupled system with differential subgrade settlement

Yu Guo,Wanming Zhai,Yu Sun 국제구조공학회 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.66 No.1

Post-construction subgrade settlement especially differential settlement, has become a key issue in construction and operation of non-ballasted track on high-speed railway soil subgrade, which may also affect the dynamic performance of passing trains. To estimate the effect of differential subgrade settlement on the mechanical behaviors of the vehicle-slab track system, a detailed model considering nonlinear subgrade support and initial track state due to track self-weight is developed. Accordingly, analysis aiming at a typical high-speed vehicle coupled with a deteriorated slab track owing to differential subgrade settlement is carried out, in terms of two aspects: (i) determination of an initial mapping relationship between subgrade settlement and track deflections as well as contact state between track and subgrade based on a semi-analytical method; (ii) simulation of dynamic performance of the coupled system by employing a time integration approach. The investigation indicates that subgrade settlement results in additional track irregularity, and locally, the contact between the concrete track and the soil subgrade is prone to failure. Moreover, wheel-rail interaction is significantly exacerbated by the track degradation and abnormal responses occur as a result of the unsupported areas. Distributions of interlaminar contact forces in track system vary dramatically due to the combined effect of track deterioration and dynamic load. These may not only intensify the dynamic responses of the coupled system, but also have impacts on the long-term behavior of the track components.

Competency-based Education: Evidence fromSocial Work Postgraduates fromFive Universities in China

Yu Guo,Chien-Chung Huang,Shuang Lu,Yuqi Wang 한국사회복지학회 2016 Asian Social Work and Policy Review Vol.10 No.3

Social work education in China has undergone rapid development during last two decades. However, methods to define, measure, and evaluate social work students’ competency remain largely unexplored. In this study, we evaluated competency in graduate social work students in China and examined factors that impacted competency, based on learning theory. Findings indicated that knowledge and skills learned in class, field placement, and social context all have effects on competency. How students think about individual development and the social work profession has the most significant effect. These findings carry implications for social work education in the Chinese context. The rapid development of social work education in China requires the effective measurement and evaluation of students’ core competencies.

Protective Effect of Sodium Ferulate on Acetaldehyde-Treated Precision-Cut Rat Liver Slices

Yu Guo,Xiao-Qian Wu,Chun Zhang,Zhang-Xiu Liao,Yong Wu,Hui Wang 한국식품영양과학회 2012 Journal of medicinal food Vol.15 No.6

Activated hepatic stellate cells (HSCs) play a key role in hepatic fibrogenesis, and inhibition of HSC activation may prevent liver fibrosis. Acetaldehyde, the most deleterious metabolite of alcohol, triggers HSC activation in alcoholic liver injury. In the present study, we investigated the protective effect of sodium ferulate (SF), a sodium salt of ferulic acid that is rich in fruits and vegetables, on acetaldehyde-stimulated HSC activation using precision-cut liver slices (PCLSs). Rat PCLSs were co-incubated with 700 lM acetaldehyde and different concentrations of SF. Hepatotoxicity was assessed by measuring enzyme leakage and malondialdehyde content in tissue. a-Smooth muscle actin, transforming growth factor-b1, and hydroxyproline were determined to assess the activation of HSCs. In addition, matrix metalloproteinase (MMP)-1 and the tissue inhibitor of metalloproteinase (TIMP-1) were determined to evaluate collagen degradation. SF prominently prevented the enzyme leakage in acetaldehyde-treated slices and also inhibited HSC activation and collagen production stimulated by acetaldehyde. In addition, SF increased MMP-1 expression and decreased TIMP-1 expression. These results showed that SF protected PCLSs from acetaldehyde-stimulated HSC activation and liver injury, which may be associated with the attenuation of oxidative injury and acceleration of collagen degradation

CITIZEN PARTICIPATION IN LOCAL BUDGETING: MECHANISMS, POLITICAL SUPPORT, AND CITY MANAGER’S MODERATING ROLE

YUGUO LIAO,YAHONG ZHANG 한국행정학회 2012 International Review of Public Administration Vol.17 No.2

Previous studies have identified several predictors of citizen participation in local budgeting, including environmental factors,engagement mechanisms, and the role of public administrators. However,none has studied the interaction effect among these factors. This study seeks to fill this research gap. It argues that the utilization of interactive engagement mechanisms and political environment will have direct impact on the level of citizen participation in budgeting. These relationships are then moderated by municipal managers’ intention to incorporate citizens. Data from a survey of New Jersey municipal administrators were used to test the hypotheses, with controlling for demographic variables in seemingly unrelated regression (SUR) models.

SYNTHESIS OF CaWO 4 AND CaWO 4 :Eu MICROSPHERES BY PRECIPITATION

YUGUO YANG,XUPING WANG,BING LIU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.1

Nearly monodisperse CaWO 4 and CaWO 4 :Eu 3 þmicrospheres have been synthesized in largescale by a surfactant-assisted solution route, in which cetyltrimethyl ammonium bromide(CTAB) is used. X-ray di®raction (XRD), scanning electron microscopy (SEM), Fourier trans-form infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and photo-luminescence (PL) were used to characterize the resulting samples. The results of XRD indicatethat the CaWO 4 and CaWO 4 :Eu 3 þsamples have the scheelite structures. The growth process ofthese nearly monodisperse spheres with an average diameter around 3.2 ? m has been examined. The results of FTIR indicate that CTAB plays an important role in the formation of micro-spheres. The CaWO 4 microspheres exhibit a blue emission band with a maximum at 423 nm. Butthe CaWO 4 :Eu 3 þmicrospheres exhibit a red emission band with a maximum at 623 nm.

Insertion Mutation in HMG-CoA Lyase Increases the Production Yield of MPA through Agrobacterium tumefaciens-Mediated Transformation

( Yuguo Dong ),( Jian Zhang ),( Rui Xu ),( Xinxin Lv ),( Lihua Wang ),( Aiyou Sun ),( Dongzhi Wei ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.11

Mycophenolic acid (MPA) is an antibiotic produced by Penicillium brevicompactum. MPA has antifungal, antineoplastic, and immunosuppressive functions, among others. β-Hydroxy-β-methylglutaryl-CoA (HMG-CoA) lyase is a key enzyme in the bypass metabolic pathway. The inhibitory activity of HMG-CoA lyase increases the MPA biosynthetic flux by reducing the generation of by-products. In this study, we cloned the P. brevicompactum HMG-CoA lyase gene using the thermal asymmetric interlaced polymerase chain reaction and gene walking technology. Agrobacterium tumefaciens-mediated transformation (ATMT) was used to insert a mutated HMG-CoA lyase gene into P. brevicompactum. Successful insertion of the HMG-CoA lyase gene was confirmed by hygromycin screening, PCR, Southern blot analysis, and enzyme content assay. The maximum MPA production by transformants was 2.94 g/l. This was 71% higher than wild-type ATCC 16024. Our results demonstrate that ATMT may be an alternative practical genetic tool for directional transformation of P. brevicompactum.

A High-speed Atomic Force Microscope for Precision Measurement of Microstructured Surfaces

Yuguo Cui,Yoshikazu Arai,Takemi Asai,BinFeng Ju,Wei Gao 한국정밀공학회 2008 International Journal of Precision Engineering and Vol.9 No.3

This paper describes a contact atomic force microscope (AFM) that can be used for high-speed precision measurements of microstructured surfaces. The AFM is composed of an air-bearing X stage, an air-bearing spindle with the axis of rotation in the Z direction, and an AFM probe unit. The traversing distance and maximum speed of the X stage are 300 ㎜ and 400 ㎜/s, respectively. The spindle has the ability to hold a sample in a vacuum chuck with a maximum diameter of 130 ㎜ and has a maximum rotation speed of 300 rpm. The bandwidth of the AFM probe unit in an open loop control circuit is more than 40 ㎑. To achieve precision measurements of microstructured surfaces with slopes, a scanning strategy combining constant height measurements with a slope compensation technique is proposed. In this scanning strategy, the Z direction PZT actuator of the AFM probe unit is employed to compensate for the slope of the sample surface while the microstructures are scanned by the AFM probe at a constant height. The precision of such a scanning strategy is demonstrated by obtaining profile measurements of a microstructure surface at a series of scanning speeds ranging from 0.1 to 20.0 ㎜/s.

A High-speed Atomic Force Microscope for Precision Measurement of Microstructured Surfaces

Cui, Yuguo,Arai, Yoshikazu,Asai, Takemi,Ju, BinFeng,Gao, Wei Korean Society for Precision Engineering 2008 International Journal of Precision Engineering and Vol.9 No.3

This paper describes a contact atomic force microscope (AFM) that can be used for high-speed precision measurements of microstructured surfaces. The AFM is composed of an air-bearing X stage, an air-bearing spindle with the axis of rotation in the Z direction, and an AFM probe unit. The traversing distance and maximum speed of the X stage are 300 mm and 400 mm/s, respectively. The spindle has the ability to hold a sample in a vacuum chuck with a maximum diameter of 130 mm and has a maximum rotation speed of 300 rpm. The bandwidth of the AFM probe unit in an open loop control circuit is more than 40 kHz. To achieve precision measurements of microstructured surfaces with slopes, a scanning strategy combining constant height measurements with a slope compensation technique is proposed. In this scanning strategy, the Z direction PZT actuator of the AFM probe unit is employed to compensate for the slope of the sample surface while the microstructures are scanned by the AFM probe at a constant height. The precision of such a scanning strategy is demonstrated by obtaining profile measurements of a microstructure surface at a series of scanning speeds ranging from 0.1 to 20.0 mm/s.

Study on morphology and photoluminescence of Au/SiO2 nanocomposite films

Aichun Yang,Yuguo Li,Boshi Zhuo,Ruiqin Peng,Xuelei Zheng 한국물리학회 2012 Current Applied Physics Vol.12 No.1

Au/SiO2 nanocomposite films were fabricated on Si (111) substrates by radio frequency (RF) magnetron sputtering technique and annealing at different temperature for 20 min (mode A) and at 1000℃ for different annealing time (mode B). The nanocomposite films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and photoluminescence (PL). SEM results demonstrate that the size of Au crystallites in mode A first increases and then decreases, on increasing annealing temperature, according to the results of XRD spectra. Analysis of PL spectra in mode B shows that the intensity of the emission peak at 440 nm and 523 nm early increases and late decreases, with increasing annealing time at 1000℃. The origin of the emission peak at around 440 nm was related to the size and quantity of Au particles and one of the emission peak at around 523 nm was related to the nanostructure of films in agreement with SEM imagines. Experimental results indicated that morphology, microstructure and luminescence of Au/SiO2 nanocomposite films showed close affinity with annealing temperature and annealing time.