중국의 자동차 산업과 시장에 관한 연구

郭建磊(GUO JIAN LEI),김항석(Hang Seok Kim) 글로벌경영학회 2006 글로벌경영학회지 Vol.3 No.2

중국경제가 급격하게 발전하여 1992년부터 최근에 이르기까지 연평균9% 이상의 고속성장을 지속해 있다. 선진국 자동차시장은 성숙기에 접어들어 증가세가 둔화된 반면, 중국은 생산 방면에서 세계4위, 수요방면에서는 세계3위의 규모를 보이고 있다. 또한 2008년 올림픽, 2010세계 엑스포, 서부 대개발 프로젝트 등 잠재적 발전요소를 가지고 있다. 중국의 자동차산업도 미국. 일본. 독일. 한국 등의 자동차산업의 진출과 시장진입으로 급격히 발전하고 있다. 각 국의 자동차 업체들이 중국 자동차 시장에 진입하려는 경쟁은 점점 치열해지고 있는 상황이다. 이에 신시장 개발전략을 수립하는데 일환으로 세계중심축으로 도약하고 있는 중국시장에서 자동차구매 소비자에 대한 연구는 한국 자동차업체에 큰 도움이 될 것이다. 따라서 본 연구는 한국 자동차 업체의 중국진출전략에 대한 자료를 제공하고 중국 판매시장에서 향후 마케팅 전략을 제시한다 While the car market in developed counties is entering upon the phase of maturity, that in China is showing rapid growth, ranking the 4th in manufacturing and the 3rd in demand. In addition, there are potential elements for development such as the Great West Development Project, the Beijing Olympic Games in 2008 and the Shanghai World EXPO in 2008. The global car industry calls China as an incomplete gigantic market . Around ten leading automobile companies have already advanced to the car market in China and are harshly competing for preoccupying the market. In order for Korean companies, which are late starters, to gain an advantage over leading foreign companies, they must exercise their strong points, Reinforce their weak points, Utilize opportunities and prepare against threats.

Coordinated Output Regulation of Heterogeneous Multi-agent Systems Under Switching Disconnected Topologies

Jian Sun,Chen Guo,Lei Liu,Qihe Shan 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.4

This paper deals with the coordinated output regulation problem of heterogeneous multi-agent systems under switching disconnected topologies. The main difficulty is that the outputs of some disconnected agents can inevitably deviate from the divergent trajectories of exosystems across some periods. To break through this challenge, we propose an interesting approach named piecewise time unit approach, in which each switching interval consists of several time units. By analyzing the trajectories of error states under the distributed observer-based control, the decreasing properties of switching behaviors can be obtained to overcome the divergence of error states. Based on this, the sufficient conditions guaranteeing the output regulation can be obtained. Finally, a simulation example is given to demonstrate our results.

A 3-D Steady-State Analysis of Thermal Behavior in EHV GIS Busbar

Lei, Jin,Zhong, Jian-ying,Wu, Shi-jin,Wang, Zhen,Guo, Yu-jing,Qin, Xin-yan The Korean Institute of Electrical Engineers 2016 Journal of Electrical Engineering & Technology Vol.11 No.3

Busbar has been used as electric conductor within extra high voltage (EHV) gas insulated switchgear (GIS), which makes EHV GIS higher security, smaller size and lower cost. However, the main fault of GIS is overheating of busbar connection parts, circuit breaker and isolating switch contact parts, which has been already restricting development of GIS to a large extent. In this study, a coupled magneto-flow-thermal analysis is used to investigate the thermal properties of GIS busbar in steady-state. A three-dimensional (3-D) finite element model (FEM) is built to calculate multiphysics fields including electromagnetic field, flow field and thermal field in steady-state. The influences of current on the magnetic flux density, flow velocity and heat distribution has been investigated. Temperature differences of inner wall and outer wall are investigated for busbar tank and conducting rod. Considering the end effect in the busbar, temperature rise difference is compared between end sections and the middle section. In order to obtain better heat dissipation effect, diameters of conductor and tank are optimized based on temperature rise simulation results. Temperature rise tests have been done to validate the 3-D simulation model, which is observed a good correlation with the simulation results. This study provides technical support for optimized structure of the EHV GIS busbar.

Effects of Stellate Ganglion Block on the Peri-operative Vasomotor Cytokine Content and Intrapulmonary Shunt in Patients with Esophagus Cancer

Guo, Wei,Jin, Xiao-Ju,Yu, Jun,Liu, Yang,Zhang, Jian-Ping,Yang, Da-Wei,Zhang, Lei,Guo, Jiang-Rong Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.21

Objective: To investigate the effects of stellate ganglion block (SGB) on the peri-operative vasomotor cytokine content and intrapulmonary shunt in patients with esophagus cancer who underwent thoracotomy. Materials and Methods: Forty patients undergoing elective resection of esophageal cancer patients who had I~II American Society of Anesthesiologist (ASA) were randomly divided into total intravenous anesthesia group (group N, n=20) and total intravenous anesthesia combined with SGB group (group S, n=20, 0.12 mL/kg 1% lidocaine was used for SGB 10 min before induction). Heart rate (HR), mean arterial pressure (MAP), central venous pressure (CVP), mean pulmonary arterial pressure (MPAP) and continuous cardiac output (CCO) were continuously monitored. The blood from internal jugular vein was drawn respectively before induction ($T_0$), and 30 min ($T_1$), 60 min ($T_2$) and 120 min ($T_3$) after one-lung ventilation (OLV), and 30 min (T4) after two-lung ventilation. The contents of plasma endothelin (ET), nitric oxide (NO) and calcitonin gene-related peptide (CGRP) were detected with enzyme linked immunosorbent assay (ELISA). Meanwhile, arterial and mixed venous blood samples were collected for determination of blood gas and calculation of intrapulmonary shunt fraction (Qs/Qt). Results: During OLV, ET contents were increased significantly in two groups (P<0.05), and no significant difference was presented (P>0.05). NO content in group S was obviously higher than in group N at T3 (P<0.05), whereas CGRP content in group N was markedly lower than in group S at each time point (P<0.05). Qs/Qt was significantly increased in both groups after OLV, but there was no statistical significant regarding the Qs/Qt at each time point between two groups. Conclusions: Total intravenous anesthesia combined with SGB is conducive to regulation of perioperative vasomotor cytokines in thoracotomy, and has little effect on intrapulmonary shunt at the time of OLV.

Novel Buck Mode Three-Level Direct AC Converter with a High Frequency Link

Lei Li,Yue Guan,Kunshan Gong,Guangqiang Li,Jian Guo 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.2

A novel family of Buck mode three-level direct ac converters with a high frequency link is proposed. These converters can transfer an unsteady high ac voltage with distortion into a regulated sinusoidal voltage with a low THD at the same frequency. The circuit configuration is constituted of a three-level converter, high frequency transformer, cycloconverter, as well as input and output filters. The topological family includes forward, push-pull, half-bridge, and full-bridge modes. In order to achieve a reliable three-level ac-ac conversion, and to overcome the surge voltage and surge current of the cycloconverter, a phase-shifted control strategy is introduced in this paper. A prototype is presented with experimental results to demonstrate that the proposed converters have five advantages including high frequency electrical isolation, lower voltage stress of the power switches, bi-directional power flow, low THD of the output voltage, and a higher input power factor.

A Study of Urodynamic Parameters at Different Bladder Filling Stages for Predicting Upper Urinary Tract Dilatation

Lei Lyu,Ya Xiong Yao,Er Peng Liu,Yan Ping Zhang,Hui Jie Hu,Feng Ping Ji,Qing Song Pu,Xing Huan Yang,Qing Wei Wang,Yan Wang,Jian Guo Wen 대한배뇨장애요실금학회 2022 International Neurourology Journal Vol.26 No.1

Purpose: To identify more accurate predictors of upper urinary tract dilatation (UUTD) in neurogenic bladder (NB) children, we studied the relationship among urodynamic parameters at different bladder filling stages, detrusor leak point pressure (DLPP) and UUTD. Methods: A total of 158 children (3–16 years) with NB were included and then divided into 2 groups according to whether their NB diagnosis was complicated with UUTD: the UUTD group (39 patients) and those without UUTD group (control group, 119 patients). The bladder filling phase was divided into 3 equal parts: the early, middle, and end filling stages. The bladder compliance (BC) and detrusor pressure (△Pdet) at each phase and DLPP at the end filling stage were recorded. Results: A BC<8 mL/cm H2O both in the middle and end stages is more specific than a BC<9 mL/cm H2O in the end stage (72%, 73%, vs. 66%), and △Pdet >8 cm H2O in the early stage, 20 cm H2O in the middle stage and 25 cm H2O in the end stage are more sensitive than △Pdet >40 cm H2O in the end stage (82%, 85%, 85%, vs. 49%). A DLPP cutoff value of 20 cm H2O showed higher sensitivity for predicting UUTD than 40 cm H2O. Conclusions: Low BC and a high △Pdet in the middle and end filling stages are more accurate factors than classic indicators for predicting UUTD. In addition, a DLPP value of >20 cm H2O in the end bladder filling stage shows high sensitivity.

A 3-D Steady-State Analysis of Thermal Behavior in EHV GIS Busbar

Jin Lei,Jian-ying Zhong,Shi-jin Wu,Zhen Wang,Yu-jing Guo,Xin-yan Qin 대한전기학회 2016 Journal of Electrical Engineering & Technology Vol.11 No.3

Busbar has been used as electric conductor within extra high voltage (EHV) gas insulated switchgear (GIS), which makes EHV GIS higher security, smaller size and lower cost. However, the main fault of GIS is overheating of busbar connection parts, circuit breaker and isolating switch contact parts, which has been already restricting development of GIS to a large extent. In this study, a coupled magneto-flow-thermal analysis is used to investigate the thermal properties of GIS busbar in steady-state. A three-dimensional (3-D) finite element model (FEM) is built to calculate multiphysics fields including electromagnetic field, flow field and thermal field in steady-state. The influences of current on the magnetic flux density, flow velocity and heat distribution has been investigated. Temperature differences of inner wall and outer wall are investigated for busbar tank and conducting rod. Considering the end effect in the busbar, temperature rise difference is compared between end sections and the middle section. In order to obtain better heat dissipation effect, diameters of conductor and tank are optimized based on temperature rise simulation results. Temperature rise tests have been done to validate the 3-D simulation model, which is observed a good correlation with the simulation results. This study provides technical support for optimized structure of the EHV GIS busbar.

Invited Mini Review : Splicing and alternative splicing in rice and humans

Zhi Guo E,Lei Wang,Jian Hua Zhou 생화학분자생물학회(구 한국생화학분자생물학회) 2013 BMB Reports Vol.46 No.9

Novel Buck Mode Three-Level Direct AC Converter with a High Frequency Link

Li, Lei,Guan, Yue,Gong, Kunshan,Li, Guangqiang,Guo, Jian The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.2

A novel family of Buck mode three-level direct ac converters with a high frequency link is proposed. These converters can transfer an unsteady high ac voltage with distortion into a regulated sinusoidal voltage with a low THD at the same frequency. The circuit configuration is constituted of a three-level converter, high frequency transformer, cycloconverter, as well as input and output filters. The topological family includes forward, push-pull, half-bridge, and full-bridge modes. In order to achieve a reliable three-level ac-ac conversion, and to overcome the surge voltage and surge current of the cycloconverter, a phase-shifted control strategy is introduced in this paper. A prototype is presented with experimental results to demonstrate that the proposed converters have five advantages including high frequency electrical isolation, lower voltage stress of the power switches, bi-directional power flow, low THD of the output voltage, and a higher input power factor.

Mesenchymal Stem Cells Modified with Stromal Cell-Derived Factor 1б Improve Cardiac Remodeling via Paracrine Activation of Hepatocyte Growth Factor in a Rat Model of Myocardial Infarction

Junming Tang,Jianing Wang,Linyun Guo,Xia Kong,Jianye Yang,Fei Zheng,Lei Zhang,Yongzhang Huang 한국분자세포생물학회 2010 Molecules and cells Vol.29 No.1

Mesenchymal stem cells (MSCs) are a promising source for cell-based treatment of myocardial infarction (MI), but existing strategies are restricted by low cell survival and engraftment. We examined whether SDF-1 transfection improve MSC viability and paracrine action in infarcted hearts. We found SDF-1-modified MSCs effectively ex-pressed SDF-1 for at least 21days after exposure to hy-poxia. The apoptosis of Ad-SDF-1-MSCs was 42% of that seen in Ad-EGFP-MSCs and 53% of untreated MSCs. In the infarcted hearts, the number of DAPI-labeling cells in the Ad-SDF-1-MSC group was 5-fold that in the Ad-EGFP-MSC group. Importantly, expression of antifibrotic factor, HGF, was detected in cultured MSCs, and HGF expression lev-els were higher in Ad-SDF-MSC-treated hearts, compared with Ad-EGFP-MSC or control hearts. Compared with the control group, Ad-SDF-MSC transplantation significantly decreased the expression of collagens I and III and matrix metalloproteinase 2 and 9, but heart function was im-proved in d-SDF-MSC-treated animals. In conclusion, SDF-1–modified MSCs enhanced the tolerance of engrafted MSCs to hypoxic injury in vitro and improved their viability in infarcted hearts, thus helping preserve the contractile function and attenuate left ventricle (LV) remodeling, and this may be at least partly mediated by enhanced paracrine signaling from MSCs via antifibrotic factors such as HGF.