http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Operation Method for Hybrid UPS with Energy Storage System Function
오진홍,이정훈,류제창,이홍원,채홍문,김재언 대한전기학회 2019 Journal of Electrical Engineering & Technology Vol.14 No.5
With the increasingly widespread use of modern communication systems, advanced medical equipment, advanced living facilities, and emergency systems requiring high-quality energy, there is an increasing need for reliable, efficient, and uninterrupted electricity supplies. Consequently, Uninterruptible Power Supplies (UPS) have recently experienced growing demand. However, because the stored energy of a UPS battery is only used in emergency situations, the battery utilization rate of a UPS is very low. Therefore, a hybrid UPS that integrates an Energy Storage System (ESS) with a UPS has recently been developed. Unlike the conventional UPS, this hybrid UPS can increase the battery utilization rate by using the stored energy of the battery when the grid is under normal operation. However, when a grid fault occurs, the hybrid UPS has to supply emergency power to critical loads. Therefore, transient voltage across the DC-link that could affect the power quality of critical loads can occur during mode transition. This paper proposes the operation method of a hybrid UPS with ESS function to minimize the transient voltage across the DC-link. PSCAD/EMTDC software is used to verify the validity of the proposed operation method.
성인원외폐렴의 원인미생물에대한 전향적 다기관 연구 : 성인원외폐렴의 원인으로 세균의 역할을 중심으로
우준희,강재명,김양수,신완식,류진홍,최정현,김양리,정희진,어수택,박춘식,정문현,정기석,이찬주,류지소 대한감염학회 2001 감염 Vol.33 No.1
Background : Communite-acquired peumonia (CAP) is one of the leading causes of mortality and morbidity. Despite progress in diagnostic techniques and treatments, management of pneumonia remains challenging, because the precise etiology remains uncertain in as many as 49% of cases. The limitaions of identifying etiologic agents make it necessary to use empiric antibiotics in almost all patients, and furthermore emergence of antibiotic-resistant organisms pose difficulties to the selection of an empiric antibiotic regimen. For the optimal choice of empirical antibiotics, we should know the frequency of etiologic agents and antimicrobial resistance rates in the community. Methods : A prospective multicenter study of community-acquired pneumonia in Korea was carried out between May 1997 and April 2000. The microbiologic diagnosis was based on the results of sputum culture, blood culture and pleural culture. Results : Five hundred eighty eight cases of community-acquired peumonia in 562 patients admitted to the hospitals. The mean age was 59.9 with male predominance (58.3%), and 370 (63%) had underlyin gillness. The etiologic agents were identified in 38.3%, and the list of individual agents, in decreasing order, was Streprococcus pneumoniae (21.7%), Klebsiella pneumoniae (14.8%) Pseudomonas aeruginosa (9.8%), Staphylococcus aureus (9.5%), viridans group streptococci (5.7%), Enterobacter cloacae (4.2%), Hemophillus Influenza (3.8%), The rates of admission to the intensive care unit was 10.4%. The motality was 7.1%. Susceptible rates of S. pneumoniae to penicillin was 36.6% and showed multidrug resistant. Forty percents of S. aureus were methicillin-resistant S. aureus. K. penumoniae were susceptible to cephalosporin and quinolone. Conclusion : In Korea, S.pneumoniae is the most important agent causing community-acquired pneumonia. Susceptible rates of S. pneumoniae to penicillin was 36.6% and showed multidrug resistant. Gram negative bacteria such as K. pneumoniae, P. aeruginosa showed high incidence when compared with that of other countries. Most of them had underlying diseases including bronchiectasis and chronic obstructive pulmonary diseases. (Korean J Infect Dis 33:1∼7, 2001)