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功率LED替代灯的新颖谐振式Buck镇流器

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电工技术学报 2012年第4期27卷 159-165页

作者：曲小慧 siu chung wong Chi Kong Tse 张建忠东南大学电气工程学院南京210096 香港理工大学电子及资讯工程学系中国香港

LED灯发光效率高,寿命长,因此具有巨大的应用前景,并有望取代白炽灯。LED灯是低压电流型器件,需要LED镇流器(驱动电路)将公共电网的高压交流电转换为适合LED的低压直流电。为了保证整个LED照明系统具有高效率和长寿命,LED镇流器必须具... 详细信息

LED灯发光效率高,寿命长,因此具有巨大的应用前景,并有望取代白炽灯。LED灯是低压电流型器件,需要LED镇流器(驱动电路)将公共电网的高压交流电转换为适合LED的低压直流电。为了保证整个LED照明系统具有高效率和长寿命,LED镇流器必须具有以上特性。相比于采用变压器降压,无变压器的降压变换器可以达到更高的效率,但此类变换器,如Buck变换器,在低占空比时要承受长时间的二极管续流,导通损耗大,效率低。因此,本文提出一种新颖的谐振式Buck镇流器,利用谐振可实现高电压转换比,转换效率高,工作时间长,且可以与已有的白炽灯调光器配合工作,可直接安装在白炽灯具上。实验结果证明了该镇流器的有效性,且成本低,适合于目前LED替代灯场合。

关键词： LED镇流器无变压器型变换器谐振式 LED替代灯

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基于LCLC恒流网络的LED自均流电路

中国电机工程学报 2016年第2期36卷 516-523页

作者：唐亚鹏曲小慧韩洪豆 siu-chung wong Chi Kong Tse 东南大学电气工程学院江苏省南京市210096 香港理工大学电子及资讯工程学系

多路半导体发光二极管(light-emitting-diode,LED)并联会造成导通电流不均衡,而电容均流方案由于其简单可靠得到广泛应用。为输出所需的LED电流,电容均流方案采用变频控制会引入无功环流,提高器件应力,而采用定频占空比控制时,变化的LE... 详细信息

多路半导体发光二极管(light-emitting-diode,LED)并联会造成导通电流不均衡,而电容均流方案由于其简单可靠得到广泛应用。为输出所需的LED电流,电容均流方案采用变频控制会引入无功环流,提高器件应力,而采用定频占空比控制时,变化的LED负载难以保证零电压开关(zerovoltage switching,ZVS)的实现。针对此问题,文中提出一种基于LCLC谐振网络的恒流源输出LED驱动电路,可有效解耦负载对输出电流的影响,定频控制,且同时实现输入阻抗为纯阻性,避免无功环流。该谐振网络亦结合电容均流方案,采用较少的器件实现多路均流。此外,该电路具有短路自保护功能,易于实现脉宽调制(pulse width modulation,PWM)调光。最后,以4条LED支路为例,搭建实验样机,实验结果证明该电路的有效性。

关键词： LED驱动电路均流谐振网络阻性输入阻抗

错位条件下基于“感应盲点”分析的非接触变压器建模及优化

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电力系统自动化 2017年第2期41卷 15-20,120页

作者：柯光洁陈乾宏徐立刚 siu-chung wong Chi K.TSE 南京航空航天大学江苏省南京市210016 香港理工大学电子及资讯工程系

感应式无线电能传输系统中,非接触变压器存在错位等多种工况,引起耦合系数等参数大范围变化,影响系统特性。为了建立错位条件下非接触变压器的耦合系数模型,文中基于场路结合的分析方法,分析磁通耦合特性,给出了非接触变压器的"感应盲点... 详细信息

感应式无线电能传输系统中,非接触变压器存在错位等多种工况,引起耦合系数等参数大范围变化,影响系统特性。为了建立错位条件下非接触变压器的耦合系数模型,文中基于场路结合的分析方法,分析磁通耦合特性,给出了非接触变压器的"感应盲点"求解方法;并结合其耦合系数的变化规律,建立非接触变压器错位条件下耦合系数的计算模型。基于磁场分布的特点,进一步提出副边多绕组的新型非接触变压器结构。采用优化后的变压器结构,设计制作了60 W输出的非接触变换器,耦合系数的计算结果和实际测试结果一致,证明了所提"感应盲点"分析方法与耦合系数计算模型的正确性,验证了优化后的新型非接触变压器具有良好的错位自适应能力。

关键词：无线电能传输感应盲点耦合系数模型非接触变压器

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S/SP非接触谐振变换器的时域特性分析

中国电机工程学报 2015年第8期35卷 1983-1992页

作者：侯佳陈乾宏任小永阮新波 siu-chung wong Chi K.Tse 江苏省新能源发电与电能变换重点实验室(南京航空航天大学自动化学院) 江苏省南京市210016 香港理工大学电子及资讯工程系

S/SP非接触谐振变换器因为对系统参数变化尤其是变压器的耦合系数变化不太敏感,具有良好的应用前景。但该变换器中主要波形谐波含量较大,导致基波分析方法误差较大,直接影响到变换器的参数设计以及控制的有效性。为此论文对变换器的时... 详细信息

S/SP非接触谐振变换器因为对系统参数变化尤其是变压器的耦合系数变化不太敏感,具有良好的应用前景。但该变换器中主要波形谐波含量较大,导致基波分析方法误差较大,直接影响到变换器的参数设计以及控制的有效性。为此论文对变换器的时域特性展开研究。论文考虑谐波影响,推导谐振网络的通用等效电路,揭示谐波产生的原因,建立谐振腔各波形的定量表达式。在时域波形分析的基础上,论文进一步研究变换器的输出增益特性,推导精确的电压增益并指出基波分析方法结果偏大的原因。最后,设计一台1.5 k W的S/SP非接触谐振变换器,特征波形、电压增益的实验与分析结果吻合良好,验证了论文所采用的时域特性分析方法的正确性。

关键词：非接触电能传输时域特性分析输出电压增益串/串并(S/SP)补偿谐振变换器

Crosstalk between degradation and bioenergetics: how autophagy and endolysosomal processes regulate energy production

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Neural Regeneration Research 2025年第3期20卷 671-681页

作者： Angelid Pabon Jagannatham Naidu Bhupana Ching-On wong Department of Biological Sciences Rutgers UniversityNewarkNJUSA

Cells undergo metabolic reprogramming to adapt to changes in nutrient availability, cellular activity, and transitions in cell states. The balance between glycolysis and mitochondrial respiration is crucial for energy production, and metabolic reprogramming stipulates a shift in such balance to optimize both bioenergetic efficiency and anabolic requirements. Failure in switching bioenergetic dependence can lead to maladaptation and pathogenesis. While cellular degradation is known to recycle precursor molecules for anabolism, its potential role in regulating energy production remains less explored. The bioenergetic switch between glycolysis and mitochondrial respiration involves transcription factors and organelle homeostasis, which are both regulated by the cellular degradation pathways. A growing body of studies has demonstrated that both stem cells and differentiated cells exhibit bioenergetic switch upon perturbations of autophagic activity or endolysosomal processes. Here, we highlighted the current understanding of the interplay between degradation processes, specifically autophagy and endolysosomes, transcription factors, endolysosomal signaling, and mitochondrial homeostasis in shaping cellular bioenergetics. This review aims to summarize the relationship between degradation processes and bioenergetics, providing a foundation for future research to unveil deeper mechanistic insights into bioenergetic regulation.

关键词： autophagy bioenergetics endolysosome energy production glycolysis metabolic reprogramming mitochondria

An overview on the chemistry, pharmacology and anticancer properties of tetrandrine and fangchinoline(alkaloids) from Stephania tetrandra roots

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Journal of Integrative Medicine 2021年第4期19卷 311-316页

作者： Eric Wei Chiang Chan siu Kuin wong Hung Tuck Chan Faculty of Applied Sciences UCSI UniversityKuala Lumpur 56000Malaysia School of Foundation Studies Xiamen University MalaysiaSelangor 43900Malaysia Secretariat of the International Society for Mangrove Ecosystems(ISME) Faculty of AgricultureUniversity of the RyukyusOkinawa 903-0129Japan

Tetrandrine(TET) and fangchinoline(FAN) are dominant bisbenzylisoquinoline(BBIQ) alkaloids from the roots of Stephania tetrandra of the family Menispermaceae. BBIQ alkaloids comprise two benzylisoquinoline units linked by oxygen bridges. The molecular structures of TET and FAN are exactly the same, except that TET has a methoxy(-OCH3) group, while FAN has a hydroxyl(-OH) group at C7. In this overview,the current knowledge on the chemistry, pharmacology and anticancer properties of TET and FAN have been updated. The focus is on colon and breast cancer cells, because they are most susceptible to TET and FAN, respectively. Against colon cancer cells, TET inhibits cell proliferation and tumor growth by inducing apoptosis and G1 cell cycle arrest, and suppresses adhesion, migration and invasion of *** breast cancer cells, FAN inhibits cell proliferation by inducing apoptosis, G1-phase cell cycle arrest and inhibits cell migration. The processes involve various molecular mechanisms and signaling pathways. Some insights on the ability of TET and FAN to reverse multi-drug resistance in cancer cells and suggestions for future research are provided.

关键词： Tetrandrine Fangchinoline Alkaloids Pharmacology Anticancer Multi-drug resistance

Prenatal diagnosis of choledochal cyst using magnetic resonance imaging: A case report

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World Journal of Gastroenterology 2005年第32期11卷 5082-5083页

作者： Alex Mun-Ching wong Yun-chung Cheung Yu-Hung Liu Koon-Kwan Ng siu-Cheung Chan Shu-Hang Ng Department of Diagnostic RadiologyChang Gung Memorial Hospital Kwei-ShanTao-YuanTaiwanChina Obstetrics and GynecologyChang Gung Memorial Hospital 222Mei Chin RoadKeelungTaiwanChina

Choledochal cysts are congenital anomalies of the biliary ducts, characterized by cystic dilatation of the *** diagnosis of this anomaly using ultrasonography (US) has been well documented. Magnetic resonance imaging (MRI) has recently become an important complement to US in prenatal diagnosis of fetal anomalies. We herein report a patient in whom at 24 wk' gestation US suggested a right upper quadrant abdominal cyst and in whom at 26 wk' gestation MRI more clearly delineated the cyst and its surrounding structures and suggested a choledochal cyst, which was confirmed at postnatal surgery and histopathology.

关键词： Choledochal cyst Prenatal diagnosis MRI

Computed tomography findings in fatal cases of enormous hepatic portal venous gas

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World Journal of Gastroenterology 2005年第19期11卷 2953-2955页

作者： siu-Cheung Chan Yung-Liang Wan Yun-chung Cheung Shu-Hang Ng Alex Mun-Ching wong Koon-Kwan Ng Department of Diagnostic Radiology Chang Gung Memorial Hospital Linko Medical Center and Keelung HospitalTaoyuanTaiwanChina

AIM: To assess the computed tomography (CT) findings in the patients with hepatic portal venous gas (HPVG) who presented with a short fatal clinical course in our hospital in order to demonstrate if there was any sign for ***: Between January 1997 and December 2000, CT scan of the abdomen was performed on 949 patients with acute abdominal pain in our emergency *** patients were found having HPVG. The CT images and clinical presentations of all these five patients were reviewed. RESULTS: In reviewing the CT findings of the cases, HPVG in bilateral hepatic lobes, abnormal gas in the superior mesenteric veins, small bowel intramural gas, and bowel distension were observed in all patients. Dry gas in multiple branches of the mesenteric vein was also revealed in all cases. All the patients expired due to irreversible septic shock within 48 h after their initial clinical presentation in emergency room. Two patients had acute pancreatitis with grade D and E Balthazar classification and they expired within 24 h due to progressing septic shock under aggressive medical treatment and life support. Two patients with underlying end stage renal disease expired within 48 h even though emergent surgical intervention was undertaken. The excited bowels revealed severe ischemic change. One patient expired only a few hours after the CT examination. CONCLUSION: HPVG is a diagnostic clue in patients with acute abdominal conditions, and CT is the most specific diagnostic tool for its evaluation. The dry mesenteric veins are the suggestive fatal sign, especially for the deteriorating patients, with the direct effect on gastrointestinal perfusion.

关键词： Hepatic portal vein Intestines Ischemia Computed tomography

Phytochemistry,pharmacology,and clinical trials of Morus alba

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Chinese Journal of Natural Medicines 2016年第1期14卷 17-30页

作者： Eric Wei-Chiang CHAN Phui-Yan LYE siu-Kuin wong Faculty of Applied Sciences UCSI University School of Science Monash University Sunway

The present review is aimed at providing a comprehensive summary on the botany,utility,phytochemistry,pharmacology,and clinical trials of Morus alba(mulberry or sang shu).The mulberry foliage has remained the primary food for silkworms for *** leaves have also been used as animal feed for livestock and its fruits have been made into a variety of food *** flavonoids as major constituents,mulberry leaves possess various biological activities,including antioxidant,antimicrobial,skin-whitening,cytotoxic,anti-diabetic,glucosidase inhibition,anti-hyperlipidemic,anti-atherosclerotic,anti-obesity,cardioprotective,and cognitive enhancement *** in anthocyanins and alkaloids,mulberry fruits have pharmacological properties,such as antioxidant,anti-diabetic,anti-atherosclerotic,anti-obesity,and hepatoprotective *** root bark of mulberry,containing flavonoids,alkaloids and stilbenoids,has antimicrobial,skin-whitening,cytotoxic,anti-inflammatory,and anti-hyperlipidemic *** pharmacological properties of *** include anti-platelet,anxiolytic,anti-asthmatic,anthelmintic,antidepressant,cardioprotective,and immunomodulatory *** trials on the efficiency of *** extracts in reducing blood glucose and cholesterol levels and enhancing cognitive ability have been *** phytochemistry and pharmacology of the different parts of the mulberry tree confer its traditional and current uses as fodder,food,cosmetics,and ***,*** is a multi-functional plant with promising medicinal properties.

关键词： Mulberry Multi-purpose Medicinal properties Morus alba