http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Hong, Min,Xin, Huanhai,Liu, Weidong,Xu, Qian,Zheng, Taiying,Gan, Deqiang The Korean Institute of Electrical Engineers 2016 Journal of Electrical Engineering & Technology Vol.11 No.2
The introduction of renewable energy sources into the AC grid can change and weaken the strength of the grid, which will in turn affect the stability and robustness of the doubly-fed induction generator (DFIG) wind farm. When integrated with weak grids, the DFIG wind turbine with vector power control often suffers from poor performance and robustness, while the DFIG wind turbine with synchronized control provides better stability. This paper investigates the critical short circuit ratios of DFIG wind turbine with vector power control and synchronized control, to analyze the stability boundary of the DFIG wind turbine. Frequency domain methods based on sensitivity and complementary sensitivity of transfer matrix are used to investigate the stability boundary conditions. The critical capacity of DFIG wind farm with conventional vector power control at a certain point of common coupling (PCC) is obtained and is further increased by employing synchronized control properly. The stability boundary is validated by electromagnetic transient simulation of an offshore wind farm connected to a real regional grid.
Investigation on the Trajectory Planning of Spray Gun of Spray Robot and Its Spraying Effect
Hong Min,Shuai Li 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.4
The industrial robot plays a very important role in stabilizing and improving the quality of products, production efficiency, working conditions and the rapid upgrading of products. It is often composed of a mechanical body, control device, driving system and detection and sensing device, and can be used in three-dimensional space to complete integration of automatic production and processing equipment. Spraying robot is one of the most important advanced coating production and processing equipment. It has the advantages of considerable flexibility and wide working scope, high spraying quality and material utilization efficiency. Due to the increasing competition for the market share, it should minimize the cost continually to accomplish the producing process. For the spraying process, how to optimize the trajectory of the spray gun and the spray parameters are the key factors to reduce the material consumption and improve the efficiency. In this paper, the spray gun trajectory and spraying effect are studied, and the experimental results show that the spray trajectory and spray effect are available. The results can also be used in other fields to get better performance.
Hongmin WANG,Haixia ZHENG,Yaowen ZHANG,Xianhong ZHANG 한국곤충학회 2018 Entomological Research Vol.48 No.6
Callosobruchus chinensis (Coleoptera: Bruchidae) is the main pest of mungbean (Vigna radiata) especially during seed storage. To provide background information for chemical ecology studies, we examined the externalmorphology of the antennal, maxillary palp and labial palp sensilla of this insect with scanning electron microscopy. The antennae of adult C. chinensis exhibited sexual dimorphism. The female have serrated antenna and the male have pectinate morphology. Eight sensillum types have been observed on the antennae of both sexes: Böhm bristles, sensilla chaetica, sensilla trichodea, sensilla basiconica, sensilla styloconicum, sensilla coeloconica, sensillum campaniformia, sensilla cavity. There are no differences on the morphology of maxillary palp and labial palp between female and male. Four different types of sensilla are present on the labial and maxillary palps of both sexes of C. chinensis: sensilla chaetica, sensilla twig basiconica, sensilla basiconica, sensilla digitiformia.
기업의 현금보유수준, 재벌여부가 내재 자기자본비용에 미치는 영향: 한국기업을 중심으로
( Hongmin Chun ) 보험연구원 2018 보험금융연구 Vol.29 No.2
본 연구는 한국기업을 대상으로 현금보유수준이 해당 기업의 자기자본비용에 미치는 영향에 대해서 실증분석을 실시하고자 한다. 더불어 해당 분석결과가 재벌기업 포함여부에 따라, 상이한 결과를 야기하는지도 연구하고자 한다. 재벌은 한국의 특수한 형태의 기업집단으로써, 재벌총수가 해당 기업에게 절대적인 권한을 행사하고 있다. 따라서 재벌기업이 초과 현금을 보유하고 있다면, 해당 기업의 대리인 비용이 증가하여 자기자본비용이 증가할 것으로 예측하였다. 본 연구 결과는 다음과 같다. 현금보유수준이 증가할수록 해당 기업의 자기자본비용은 증가하는 것으로 나타났다. 더불어 해당 경향은 재벌기업에서 강하게 나타났다. 이러한 결과는 한국에서의 높은 현금보유수준은 과대투자로 이어질 확률이 높아지고, 해당 기업의 대리인비용을 증가시켜, 결론적으로 해당 기업의 위험은 증가하는 것으로 해석 가능하다. This paper examines firms’ cash holdings and their effect on equity capital cost, distinguishing firms that belong to chaebol and non-chaebol groups. A chaebol is a South Korean form of business conglomerate. Chaebols are typically global multinationals owning numerous international enterprises, controlled by controlling shareholders with power over all operations. So this paper needs to examine whether firms’ cash holdings and their effect on the implied cost of equity capital, distinguishing firms that belong to chaebol or not. Empirical results suggest that higher cash holdings increase risk, which holds for chaebol group of firms. Thus, a poor corporate governance system for a chaebol-affiliated firm with high cash holdings could be a possible factor contributing to the risk premium. Finally, we conduct a 2SLS regression, and our empirical results are consistent for both the full and the chaebol samples, suggesting that our ordinary least squares results are valid. So in Korea, higher cash holdings represent risk premium closely related to overinvestment and agency problems between managers and shareholders.
Hydrogen Peroxide produced by Two Amino Acid Oxidases Mediates Antibacterial Actions
Hongmin Zhang,Qiuyue Yang,Mingxuan Sun,Maikun Teng,Liwen Niu 한국미생물학회 2004 The journal of microbiology Vol.42 No.4
The antibacterial actions of two amino acid oxidases, a D-amino acid oxidase from hog kidney and a L-amino acid oxidase from the venom of Agkistrodon halys, were investigated, demonstrating that both enzymes were able to inhibit the growth of both Gram-positive and Gram-negative bacteria, and that hydrogen peroxide, a product of their enzymatic reactions, was the antibacterial factor. However, hydrogen peroxide generated in the enzymatic reactions was not sufficient to explain the degree to which bacterial growth was inhibited. A fluorescence labeling assay showed that both of these two enzymes could bind to the surfaces of bacteria. To the best of our knowledge, this is the first report regarding the antibacterial activity of the D-amino acid oxidases.
Design of ferromagnetic shims for an HTS NMR magnet using sequential search method
Hongmin Yang,SangGap Lee,안민철 한국초전도저온학회 2021 한국초전도저온공학회논문지 Vol.23 No.4
This study deals with the ferromagnetic shims design based on the spherical harmonic coefficient reduction method. The designmethod using the sequential search method is an intuitive method and has the advantage of quickly reaching the optimal result. Thestudy was conducted for a 400 MHz all-REBCO magnet, which had difficulty in shimming due to the problem of SCF (screeningcurrent induced field). The initial field homogeneity of the magnet was measured to be 233.76 ppm at 20 mm DSV (DiameterSpherical Volume). In order to improve the field homogeneity of the magnet, the ferromagnetic shim with a thickness of 1 mil to11 mil was constructed by a design method in which sequential search algorithm was applied. As a result, the field homogeneityof the magnet could be significantly improved to 0.24 ppm at 20 mm DSV and 0.05 ppm at 10 mm DSV.