교역조건 충격이 GDP와 인플레이션에 미치는 영향 분석

Wei Wei,최용재 한국무역통상학회 2017 무역통상학회지 Vol.17 No.6

The purpose of this paper is to investigate the impact of terms of trade on real GDP and inflation. We estimate the cointegration relationship and vector error correction model including 5 variables such as real GDP, consumer price index, terms of trade, producer price index and won/dollar exchange rate. The empirical results show that terms of trade and inflation are cointegrated, but not the case for the terms of trade and real GDP. This means that when there is a positive terms of trade shock, inflation increases in the long-run. Specifically the one standard deviation shock of terms of trade results in 0.12 % increase in the consumer price index. However, the terms of trade shock can not explain the variation of real GDP in the long-run and there is no significant statistical relationship between two variables.

Preparation and evaluation of solvent extractant- impregnated sorbent

( Wei Wei ),원성욱,윤영상 한국공업화학회 2013 한국공업화학회 연구논문 초록집 Vol.2013 No.-

Kinetics studies of dimethyl carbonate synthesis from urea and methanol over ZnO catalyst

Wei Wei,Junliang Zhang,Feng Wang,Fukui Xiao,Yuhan Sun 한국화학공학회 2010 Korean Journal of Chemical Engineering Vol.27 No.6

A kinetic experiment of dimethyl carbonate (DMC) synthesis by urea methanol over ZnO catalyst was carried out in an isothermal fixed-bed reactor. A kinetic model based on the mole fraction was proposed and the kinetic parameters were estimated from the experimental results. The model predictions were compared with the experimental data and fair agreements were found. The effects of the reaction temperature (443-473 K), space time (0-4.7 h mol−1kgcat) and urea mass percent (5-9%) in feed on DMC mole fraction were investigated. It was found that the reactions are mainly influenced by the reaction temperature and space time rather than urea mass percent in feed. The experimental and simulated results indicated that the reaction from MC to DMC was the rate-controlling step in the DMC synthesis process from urea and methanol. It is important to remove the DMC and byproduct ammonia to achieve a high selectivity of DMC. This implies that reactive distillation might be used in the DMC synthesis on an industrial scale to achieve a higher selectivity of DMC.

Removal of Cd(II) by poly(styrenesulfonic acid)-impregnated alginate capsule

Wei, Wei,Bediako, John Kwame,Kim, Sok,Yun, Yeoung-Sang ELSEVIER SCIENCE B.V.; AMSTERDAM 2016 JOURNAL- TAIWAN INSTITUTE OF CHEMICAL ENGINEERS Vol.61 No.-

<P><B>Abstract</B></P> <P>In this study, a capsule type sorbent of poly(styrenesulfonic acid)-impregnated alginate capsule (PSSA-AC) was developed by using a simple and moderate method. PSSA was used as a model encapsulated material because of its large number of sulfonic acid groups which have high affinity toward Cd(II). PSSA-AC was prepared by dropping solution A (mixture of 10% (w/v) PSSA + 1% CaCl<SUB>2</SUB>) into B solution (0.6% (w/v) sodium alginate). Microscope images revealed that PSSA was well encapsulated inside of the alginate shell. The pH edge experiment indicated that Cd(II) sorption was influenced marginally by the experimental pH range. The maximum Cd(II) uptake by PSSA-AC was as high as 184.12 ± 6.30 mg/g. The kinetic and FTIR studies demonstrated that ion-exchange was the main sorption mechanism. The PSSA-AC could be regenerated by using 2% CaCl<SUB>2</SUB> as a desorbing agent.</P> <P><B>Highlights</B></P> <P> <UL> <LI> PSSA-AC was successfully developed using a simple and moderate method. </LI> <LI> The maximum Cd(II) uptake was 184.12 ± 6.30 mg/g using Langmuir isotherm model. </LI> <LI> The Cd(II)-loaded PSSA-AC was easily regenerated by using 2% CaCl<SUB>2</SUB> solution. </LI> <LI> The overall sorption/desorption mechanism was cation ion-exchange between Cd(II) and Ca(II). </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Theoretical Analysis on Molecular Magnetic Properties of N-Confused Porphyrins and Its Derivatives

Wei, Wei,Bai, Fu-Quan,Xia, Bao-Hui,Zhang, Hong-Xing Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.9

We have theoretically investigated the magnetic properties of N-confused porphyrin (NCP), tetraphenyl-N-confused porphyrin (TPNCP) and their substituted derivatives with O, S and Se heteroatoms (2ONCP, 2STPNCP, 2SeNCP, 2OTPNCP, etc.) by using DFT method. In the minimum energy structures of the 2OTPNCP, the two couples opposite phenyl substitutes are staggered. In the case of TPNCP, 2STPNCP and 2SeTPNCP, two phenyls being respectively close to or opposite to N-confused pyrrole are found to be pointed the same direction, whilst others are in the opposite direction. Based on the equilibrium structures, the $^1H$ chemical shifts and nucleus-independent chemical shifts (NICS) are calculated in this paper. The ${\pi}$ current density being induced by the tridimensional perpendicular magnetic field transmits the inner section of the pyrrole segments for NCP and TPNCP. As for their substituted derivatives with O, S and Se atoms, the current path passes through the outer section of the two heterorings. The NICS values at the ring critical points of the heterorings are much lower (in absolute value) than those of which is at the center of an isolated pyrrole molecule. The $^1H$ NMR for ${\beta}H$ atoms of the heterorings decreases from O, S to with Se.

Adaptive Differentiated Integrated Routing Scheme for GMPLS-based Optical Internet

Wei, Wei,Zeng, Qingji,Ye, Tong,Lomone, David The Korea Institute of Information and Commucation 2004 Journal of communications and networks Vol.6 No.3

A new online multi-layer integrated routing (MLIR) scheme that combines IP (electrical) layer routing with WDM (optical) layer routing is investigated. It is a highly efficient and cost-effective routing scheme viable for the next generation integrated optical Internet. A new simplified weighted graph model for the integrated optical Internet consisted of optical routers with multi-granularity optical-electrical hybrid switching capability is firstly proposed. Then, based on the proposed graph model, we develop an online integrated routing scheme called differentiated weighted fair algorithm (DWFA) employing adaptive admission control (routing) strategies with the motivation of service/bandwidth differentiation, which can jointly solve multi-layer routing problem by simply applying the minimal weighted path computation algorithm. The major objective of DWFA is fourfold: 1) Quality of service (QoS) routing for traffic requests with various priorities; 2) blocking fairness for traffic requests with various bandwidth granularities; 3) adaptive routing according to the policy parameters from service provider; 4) lower computational complexity. Simulation results show that DWFA performs better than traditional overlay routing schemes such as optical-first-routing (OFR) and electrical-first-routing (EFR), in terms of traffic blocking ratio, traffic blocking fairness, average traffic logical hop counts, and global network resource utilization. It has been proved that the DWFA is a simple, comprehensive, and practical scheme of integrated routing in optical Internet for service providers.

Integrated Voltage and Power Flow Management Considering the Cost of Operation in Active Distribution Networks

Wei Wei,Tao Xu,Xiaoxue Wang,Chengshan Wang,Lingxu Guo,Jun Lin,Tianchu Li 대한전기학회 2016 Journal of Electrical Engineering & Technology Vol.11 No.2

The increasing penetration of distributed energy resources on the distribution networks have brought a number of technical impacts where voltage and thermal variations have been identified as the dominant effects. Active network management in distribution networks aims to integrate distributed energy resources with flexible network management so that distributed energy resources are organized to make better use of existing capacity and infrastructure. This paper propose active solutions which aims to solve the voltage and thermal issues in a distributed manner utilizing a collaborative approach. The proposed algorithms have been fully tested on a distribution network with distributed generation units.

Appropriate nitrogen application enhances saponin synthesis and growth mediated by optimizing root nutrient uptake ability

Wei, Wei,Ye, Chen,Huang, Hui-Chuan,Yang, Min,Mei, Xin-Yue,Du, Fei,He, Xia-Hong,Zhu, Shu-Sheng,Liu, Yi-Xiang The Korean Society of Ginseng 2020 Journal of Ginseng Research Vol.44 No.4

Background: Cultivation of medicinal crops, which synthesize hundreds of substances for curative functions, was focused on the synthesis of secondary metabolites rather than biomass accumulation. Nutrition is an important restrict factor for plant growth and secondary metabolites, but little attention has been given to the plasticity of nutrient uptake and secondary metabolites synthesis response to soil nitrogen (N) change. Methods: Two year-field experiments of Sanqi (Panax notoginseng), which can synthesize a high level of saponin in cells, were conducted to study the effects of N application on the temporal dynamics of biomass, nutrient absorption, root architecture and the relationships between these parameters and saponin synthesis. Results: Increasing N fertilizer rates could improve the dry matter yields and nutrient absorption ability through increasing the maximum daily growth (or nutrient uptake) rate. Under suitable N level (225 kg/ha N), Sanqi restricted the root length and surface and enhanced the root diameter and N uptake rate per root length (NURI) to promote nutrient absorption, but the opposite status of Sanqi root architecture and NURI was found when soil N was deficient. Furthermore, increasing N rates could promote the accumulation of saponin in roots through improving the NURI, which showed a significant positive relationship with the content of saponin in the taproots. Conclusion: Appropriate N fertilizer rates could optimize both root architecture and nutrient uptake efficiency, then promote both the accumulation of dry matter and the synthesis of saponins.

Active Disturbance Rejection Control for Nanopositioning Systems with Piezoelectric Actuators

Wei Wei,Ran Zhang,Jing Wang,Guang-Bo Hao 제어로봇시스템학회 2016 제어로봇시스템학회 국제학술대회 논문집 Vol.2016 No.10

Nanopositioning proposes a high demand for its control system. However, hysteresis, a common nonlinear phenomenon existing in piezoelectric actuator, decreases precision of nanopositioning. In this paper, active disturbance rejection control (ADRC) is designed to estimate and cancel the influence of hysteresis, and integral time absolute error (ITAE) optimal index is chosen to determine the parameters of ADRC. Simulations are performed on the basis of mathematic model of nanopositioning system, and numerical results show that ADRC is effective in the control of nanopositioning.

Discussion on the Permeable Progressive Failure Mechanism of Loess Dam

( Wei Wei ) 대한지질공학회 2019 대한지질공학회 학술발표회논문집 Vol.2019 No.2

In this research, the loess dam in Ansai District, Yan’an, Shaanxi province is taken as the monitoring object. The time node with multiple damages during the period is used as the basis for dividing the whole life cycle, the types of dam damages are distinguished according to the internal factors and external conditions. The dam experienced three obvious damages in the whole life cycle. The triggering factors of the three damages are different. The first damage is due to the water level difference on both sides of the dam, and the fine-grained soil in the dam is taken away from the seepage channel under the action of hydrodynamic force. The soil at the foot of the slope tends to be saturated under the action of osmotic water, and when the weight of the upper soil is greater than the shear strength of the soil at the foot of the slope, the first damage occurred. Therefore, it is called “internal erosion damage”. The second damage is due to the softening of the slope feet under the immersion of rainwater, and the slope collapses, it called “slumping damage”. The third damage is attributed to the infiltration of rainwater through the crack at the top of the dam. The soil at the top of the dam is slippery along the rainwater intrusion surface, and the width of the dam roof is continuously reduced until it completely disappears, so it called “slippery damage”. Based on this, the failure mode of loess dam is proposed.