http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : ( Seunghyeong Lee ) (검색결과 6 건)
- 무료
- 기관 내 무료
- 유료
-
A Low-Power Single Chip Li-Ion Battery Protection IC
Lee, Seunghyeong,Jeong, Yongjae,Song, Yungwi,Kim, Jongsun The Institute of Electronics and Information Engin 2015 Journal of semiconductor technology and science Vol.15 No.4
A fully integrated cost-effective and low-power single chip Lithium-Ion (Li-Ion) battery protection IC (BPIC) for portable devices is presented. The control unit of the battery protection system and the MOSFET switches are integrated in a single package to protect the battery from over-charge, over-discharge, and over-current. The proposed BPIC enters into low-power standby mode when the battery becomes over-discharged. A new auto release function (ARF) is adopted to release the BPIC from standby mode and safely return it to normal operation mode. A new delay shorten mode (DSM) is also proposed to reduce the test time without increasing pin counts. The BPIC implemented in a $0.18-{\mu}m$ CMOS process occupies an area of $750{\mu}m{\times}610{\mu}m$. With DSM enabled, the measured test time is dramatically reduced from 56.82 s to 0.15 s. The BPIC chip consumes $3{\mu}A$ under normal operating conditions and $0.45{\mu}A$ under standby mode.
-
Seunghyeong Lee,Jun-Kyu Byun,Na-Young Kim,Jonghwa Jin,Hyein Woo,최연경,Keun-Gyu Park 생화학분자생물학회 2022 BMB Reports Vol.55 No.9
Various mechanisms have been suggested to explain the chemopreventiveand tumor-inhibitory effects of melatonin. Despite thegrowing evidence supporting melatonin-induced mitochondrialdysfunction, it remains largely unknown how this phenomenonmodulates metabolic reprogramming in cancer cells. The aim ofour study was to identify the mechanism underlying the anti-proliferativeand apoptotic effects of melatonin, which is known toinhibit glycolysis. We analyzed the time-dependent effects ofmelatonin on mitochondrial respiration and glycolysis in livercancer cells. The results showed that from a cell bioenergeticpoint of view, melatonin caused an acute reduction in mitochondrialrespiration, however, increased reactive oxygen speciesproduction, thereby inhibiting mTORC1 activity from an earlystage post-treatment without affecting glycolysis. Nevertheless,administration of melatonin for a longer time reduced expressionof c-Myc protein, thereby suppressing glycolysis via downregulationof HK2 and LDHA. The data presented herein suggest thatmelatonin suppresses mitochondrial respiration and glycolysissimultaneously in HCC cells, leading to anti-cancer effects. Thus,melatonin can be used as an adjuvant agent for therapy of livercancer.
-
이승형(Seunghyeong Lee),한상우(Sangwoo Han),김종선(Jongsun Kim) 대한전자공학회 2015 전자공학회논문지 Vol.52 No.2
본 논문에서는 휴대용 기기를 위한 고효율 삼중 모드 부스트 변환기를 나타낸다. 제안하는 부스트 변환기는 펄스폭변조 방식를 사용하며 부하 전류에 따라 펄스 스키핑 모드 (Pulse Skipping Mode, PSM), 불연속 전류 모드(Discontinuous Conduction Mode, DCM) 및 연속 전류 모드 (Continuous Conduction Mode, CCM)의 세 가지 동작 모드를 갖는 것을 특징으로 한다. 또한, 전류 불연속 모드에서 역 전류 흐름 및 인덕터의 공진에 의한 발진 현상을 효과적으로 방지하기 위해 발진 억제기 (Ringing suppressor)를 적용하여 효율을 극대화 시켰다. 제안하는 부스트 변환기는 동부 0.18μm BCD 공정을 사용하여 구현되었다. 단일 셀 리튬-이온 배터리로부터 2.5V-4.2V의 가변 입력전압을 받아서 4.8V의 고정 전압을 출력하며 최대 300mA의 부하전류를 공급할 수 있다. 이 때 최대 리플 전압은 3.1mV이며, 연속 전류 모드에서 92%, 불연속 전류 모드에서 87% 이상의 높은 효율을 나타낸다. 또한, 펄스 스키핑 모드를 통해 적은 부하전류 조건하에서도 60% 이상의 효율을 가지며 모드 변경 구간에서의 효율 감소가 최소화되는 것을 특징으로 한다. This paper presents a high efficiency, PSM/DCM/CCM triple mode boost DC-DC converter for mobile application. This device operates at Pulse-Skipping Mode(PSM) when it enters light load, and otherwise operate the operating frequency of 1.4MHz with Pulse-Width Modulation(PWM) mode. Especially in order to improve the efficiency during the Discontinuous-Conduction Mode(DCM) operation period, the reverse current prevention circuit and oscillations caused by the inductor and the parasitic capacitor to prevent the Ringing killer circuit is added. The input voltage of the boost converter ranges from 2.5V ~ 4.2V and it generates the output of 4.8V. The measurement results show that the boost converter provides a peak efficiency of 92% on CCM and 87% on DCM. And an efficiency-improving PWM operation raises the efficiency drop because of transition from PWM to PFM. The converter has been fabricated with a 0.18um Dongbu BCDMOS technology.
-
( Dong-ho Kim ),( Mi-jin Kim ),( Na-young Kim ),( Seunghyeong Lee ),( Jun-kyu Byun ),( Jae Won Yun ),( Jaebon Lee ),( Jonghwa Jin ),( Jina Kim ),( Jungwook Chin ),( Sung Jin Cho ),( In-kyu Lee ),( Yeo 생화학분자생물학회 2022 BMB Reports Vol.55 No.11
Sorafenib, originally identified as an inhibitor of multiple oncogenic kinases, induces ferroptosis in hepatocellular carcinoma (HCC) cells. Several pathways that mitigate sorafenib-induced ferroptosis confer drug resistance; thus strategies that enhance ferroptosis increase sorafenib efficacy. Orphan nuclear receptor estrogen-related receptor γ (ERRγ) is upregulated in human HCC tissues and plays a role in cancer cell proliferation. The aim of this study was to determine whether inhibition of ERRγ with DN200434, an orally available inverse agonist, can overcome resistance to sorafenib through induction of ferroptosis. Sorafenib-resistant HCC cells were less sensitive to sorafenibinduced ferroptosis and showed significantly higher ERRγ levels than sorafenib-sensitive HCC cells. DN200434 induced lipid peroxidation and ferroptosis in sorafenib-resistant HCC cells. Mechanistically, DN200434 increased mitochondrial ROS generation by reducing glutathione/glutathione disulfide levels, which subsequently reduced mTOR activity and GPX4 levels. DN200434- induced amplification of the antitumor effects of sorafenib was confirmed in a tumor xenograft model. The present results indicate that DN200434 may be a novel therapeutic strategy to re-sensitize HCC cells to sorafenib. [BMB Reports 2022; 55(11): 547-552]
-
-
김희선(Hee Seon Kim),신동현(Dong Hyun Shin),이승현(Seunghyeong Lee),송순호(Soonho Song),전광민(Kwang Min Chun) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.12
The goal of this study is to experimentally evaluate the effects of different types of catalysts, GHSV (Gas Hourly Space Velocity) and O<SUB>2</SUB>/C ratio of reactants on the performance of a methane reformer, which was designed and built to produce syngas in the laboratory. Two different types of catalysts were employed ?a precious metal catalyst (monolith type) consisting of 1wt% Rh/CeO<SUB>2</SUB>-ZrO<SUB>2</SUB> and a mixed catalyst consisting of 1wt% Rh/CeO<SUB>2</SUB>-ZrO<SUB>2</SUB> (monolith type) and 18wt% Ni on calcium aluminate catalyst (pellet type). The O<SUB>2</SUB>/C ratio of reactants was varied from 0.25 to 1.0 and GHSV was ranged from 5,000h<SUP>-1</SUP> to 10,000h<SUP>-1</SUP>. For each experimental condition, the catalyst temperature (the temperature of the reaction mixture) and concentrations of product gases (H<SUB>2</SUB>, CO, CO<SUB>2</SUB>) were measured. The results showed that both catalyst temperature and syngas concentration were increased as GHSV increased up to 10,000h<SUP>-1</SUP>, and the precious metal catalyst showed the better performance than the mixed catalyst. However, performance of the reformer was deteriorated when the O<SUB>2</SUB>/C ratio was increased above 0.75.
KISS연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
