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 : Fred Wang (검색결과 5 건)
- 무료
- 기관 내 무료
- 유료
-
FRED T. ISHUGAH, RUZHU WANG,LIWEI WANG,ZISHENG LU 대한설비공학회 2014 International Journal Of Air-Conditioning and Refr Vol.22 No.2
This study aimed at analyzing different operation strategies to improve the performance of anew type adsorption chiller employing a novel composite adsorbent, silica gel impregnated withlithium chloride, paired with methanol as the adsorbate. The chiller's experimental test resultsshowed an average Specific. Cooling Power (SCP) and Coeffient of Performance (COP) of286 W/kg and 0.48, respectively. This was when the average hot water inlet temperature,cooling water inlet temperature, and chilled water inlet temperature were 83C, 26C and 15C,respectively. In addition, the corresponding mass flow rates were 0.22, 0.39 and 0.09 kg/s, respectively. Despite the fact that the average SCP and COP, were rather satisfactory, analysis ofexperimental results conducted with different cycle times, inlet hot water temperatures, and hotwater flow rates showed that a much better performance could be achieved. Experimentalresults indicated the following: (1) the COP increased while the SCP decreased with increasedcycle time, (2) both the COP and the SCP increased with increase in heat and mass recoverytime to an optimal time then started to decrease as heat and mass recovery time increasedbeyond the optimal time, (3) both the cooling power and COP generally increased with increasein inlet hot water temperature at a relatively higher value from 60C to about 90C beyondwhich the incremental value started diminishing, and, (4) increase in mass flow rates producedhigher cooling power with decreased COP while decrease in mass flow rates of hot water producedlower cooling power with increased COP. This paper therefore recommends an adsorption/desorption time, heat and mass recovery time, inlet hot water temperature, and hot watermass flow rate of 780 s, 60 s, 83C, and 0.22 kg/s as appropriate to give the best chiller performancefor refrigeration.
-
Fast Wide-bandgap Device Overcurrent Protection with Direct Current Measurement
Wen Zhang,Fred Wang,Zheyu Zhang,Bernhard Holzinger 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5
A fast and reliable overcurrent protection scheme is crucial for the converter reliability. It is also critical for double pulse test stations where newer devices or even engineering samples are tested, and device failures can be costly. A fast overcurrent protection scheme using the direct current measurement in the double pulse test is demonstrated and 7.55 ns fault response delay time is achieved. The total fault clearing time is determined by the fault signal propagation and device switching speed. Around 100 ns and 60 ns fault clearing time is achieved for SiC and GaN devices, respectively. The much faster protection can potentially simplify the gate driver design and reduce the energy rating of the coaxial shunt resistor. Since the overcurrent detection is directly attached to the current measurement, its impact on the measurement bandwidth is also discussed.
-
-
High Temperature Packaging of 50 ㎾ Three-Phase SiC Power Module
Fan Xu,Dong Jiang,Jing Wang,Fred Wang,Leon M. Tolbert,Timothy Junghee Han,Jim Nagashima,Sung Joon Kim 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5
Research on silicon carbide (SiC) power electronics has shown their advantages in high temperature and high efficiency applications. This paper presents a SiC JFET based, 200 ℃, 50 ㎾ three-phase inverter module and evaluates its electrical performance. With 1200 V, 100 A rating of the module, each switching element is composed of four paralleled SiC JFETs (1200 V/25 A each) and two anti-parallel SiC Shottky Barrier Diodes (SBDs). The substrate layout inside the module is designed to reduce package parasitics. Then, experimental static characteristics of the module are obtained over a wide range of temperature, and low on-state resistance is shown up to 200 ℃. A gate driver, with different turn-on, turn-off gate resistances and RCD network, is designed to optimize the switching performances. The module is verified to have low power loss, fast switching characteristics at 650 V dc bus voltage, 60 A drain current, in both simulation and experiments. Finally, switching time and losses, obtained from simulation and experiment, are compared.
-
Lee, Eun-Ju,Mcclelland, Michael,Wang, Yipeng,Long, Fred,Choi, Sang-Ho,Lee, Je-Ho Pergamon Press 2009 Oncology Research Vol.18 No.9
<P>Alterations in DNA methylation offer unique prospects as tumor markers. The big limitation in cervical cancer research is that it is too hard to obtain the pure normal tissue from a cervical cancer mass. So, we first profile type-specific DNA methylation of major two types of human uterine cervical cancer, adenocarcinoma (ACA) and squamous cell carcinoma (SCC), to establish a precise source of marker research. To assess the DNA methylation status of promoter regions in human uterine cervical ACAs and SCCs, fresh frozen tissues were obtained from bulky tumor masses to minimize the contamination from normal tissues and two array platforms using digestion with methylation-sensitive restriction-enzyme HpaII, ligation, and PCR were performed: an array of 11,994 (approximately 1.5 kb) PCR products from 10,445 promoter regions, and an array of 355,264 oligonucleotides for 18,212 HpaII fragments in 12,617 promoter regions. Loci near 21 genes showed significant differences between six ACA and four SCC from the analysis of two array data. Real-time PCR-based validation was performed on 13 loci using other nearby candidate methylation targets in the same promoter. Methylation patterns of 11 of 13 linked loci concurred with the microarray results. Four loci were further studied using tissues from additional patients (23 ACA and 24 SCC). Hypermethylation of loci in PAK6 and NOGOR most strongly correlated with ACA. Therefore, we have identified the 21 genes with differential methylation pattern between ACA and SCC and, furthermore, we found that PAK6 and NOGOR could be useful markers of ACA to be distinct from SCC.</P>
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
