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Chinese Journal of Polymer Science 1995年第4期13卷 289-314页

作者： kam W.Leong 毛海泉卓仁禧 Department of Biomedical Engineering School of Medicine The Johns Hopkins University Baltimore MD 21205 USA Department of Chemistry Wuhan University Wuhan 430072

This review provides a glimpse of the potential of the biodegradable phos-phoryl-containing polymers in medical applications. Undoubtedly these polymerspossess unique properties that are yet to be fully understood. Many areas warrantfurther investigation and much optimization remains to be done. The fascinatingchemistry of phosphorus poses interesting hurdles but at the same time leavesample room for polymer scientists to exercise their creativity in designinginteresting biomaterials. As the mutual understanding between basic and clinicalscientists on the need of medical devices and the capabilities of these newbiomaterials expands, imaginative application of new biomaterials to other medi-cal applications can be expected.

关键词： biodegradable polymers phosphoryl-containing backbone controlled drug delivery

Exact joint laws associated with spectrally negative Levy processes and applications to insurance risk theory

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Frontiers of Mathematics in China 2014年第6期9卷 1453-1471页

作者： Chuancun YIN kam C. YUEN School of Mathematical Sciences Qufu Normal University Qufu 273165 China Department of Statistics and Actuarial Science The University of Hong Kong Hong KongChina

We consider the spectrally negative L@vy processes and determine the joint laws for the quantities such as the first and last passage times over a fixed level, the overshoots and undershoots at first passage, the minimum, the maximum, and the duration of negative values. We apply our results to insurance risk theory to find an explicit expression for the generalized expected discounted penalty function in terms of scale functions. Furthermore, a new expression for the generalized Dickson＇s formula is provided.

关键词： Fluctuation identity spectrally negative L6vy processes supremaand infima generalized Dickson's formula scale function occupation time

Pharmacological Investigation on the Qi-Invigorating Action of Schisandrin B: Effects on Mitochondrial ATP Generation in Multiple Tissues and Innate/Adaptive Immunity in Mice

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Perspectives on the linkage between typhoon activity and global warming from recent research advances in paleotempestology

Chinese Medicine（中医） 2024年第2期 15页

作者： Hoi Yan Leung Suen Chit Sze kam Ming Ko

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Chinese Science Bulletin 2008年第19期53卷 2907-2922页

作者： FAN DaiDu LIU kam-biu State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China Department of Oceanography and Coastal Sciences Louisiana State University Baton Rouge LA 70803 USA State Key Laboratory of Coast and Estuarine Science East China Normal University Shanghai 200062 China

The recent increase in typhoon (tropical cyclone) activity has attracted great interest and induced heated debates over whether it is linked to global warming or only a return to an active phase of the well-known multi-decadal variability. Due to the short instrumental record, our knowledge is quite scarce on the complex processes and mechanism of typhoon generation, development, and evolution, especially for the rare but highly destructive super-typhoons. It is therefore very important to extend the time span of typhoon activity records. Paleotempestology, a young science that emerged in the early 1990s, studies past typhoon activity spanning several centuries to millennia before the instrumental era through the use of geological proxies and historical documentary records. This paper presents a brief review and synthesis on the major research advances and findings of paleotempestology with an emphasis on proxy technique development and applications. The methodology has been evolving from single geologic proxy to multi-proxy techniques by integrating microfossils, sedimentary organic elemental ratios, and stable isotopes, together with typical sedimentary textures and structures, for the diagnosis of storm deposits. A newly-developed proxy technique is employing oxygen isotopes preserved in growing laminae of tree rings, cave stalagmites, and reef corals to diagnose typhoon rainwater impacts. Historical documentary records have been systematically compiled and analyzed to reconstruct the history of typhoon activity in some regions. The extracted typhoon-proxy data show that there does not exist a simple linear relationship between typhoon frequency and Holocene climate (temperature) change. Typhoon activity should have a secular and constant linkage with ENSO fluc- tuations, in that more typhoons and hurricanes make landfalls in China, Central and North America during La Ni?a years than El Ni?o years. This finding is consistent with that derived from recent in- stru

关键词：台风暴风雨灾害天气全球升温问题

Valuation of CDS counterparty risk under a reduced-form model with regime-switching shot noise default intensities

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Frontiers of Mathematics in China 2017年第5期12卷 1085-1112页

作者： Yinghui DONG kam Chuen YUEN Guojing WANG Department of Mathematics and Physics Suzhou University of Science and TechnologySuzhou 215009 China Department of Statistics and Actuarial Science University of Hong Kong Hong KongChina Department of Mathematics and Center for Financial Engineering Soochow UniversitySuzhou 215006 China

We study the counterparty risk for a credit default swap （CDS） in a regime-switching market driven by an underlying continuous-time Markov chain. We model the default dependence via some correlated Cox processes with regime-switching shot noise intensities containing common shock. Under the proposed model, the general bilateral counterparty risk pricing formula for CDS contracts with the possibility of joint defaults is presented. Based on some expressions for the conditional Laplace transform of the integrated intensity processes, semi-analytical solution for the bilateral credit valuation adjustment （CVA） is derived. When the model parameters satisfy some conditions, explicit formula for the bilateral CVA at time 0 is also given.

关键词： Credit default swap (CDS) bilateral credit valuation adjustment,Markov chain common shock regime-switching shot noise process

Meeting the communicative demands in academic and professional training curricula: An overview of ELT in tertiary institutions in Singapore

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外语教学与研究 2001年第4期33卷 258-267页

作者： Ho Wah kam TheSingaporeTeachers'Union

This paper focuses on the upper end of the formal Singapore educational spectrum,providing an overview of ELT in polytechnics and universities. It is in four *** order to show continuity between ELT in schools and tertiary institutions,Part 1 explains briefly the nation’s language policy in *** Part 2,an attempt is made to delineate the main trends in ELT in universities and polytechnics and the approaches to ELT generally adopted for mature learners. Part 3 draws attention to the changing emphases in tertiary education in Singapore and to how students are being prepared in innovative ways in ELT for a globalised world and a knowledge based economy. Part 4 provides a summary of the paper.

关键词：英语教学高等院校教学方法语言交际能力

Uniform Asymptotics for Finite-time Ruin Probability in a Dependent Risk Model with General Stochastic Investment Return Process

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Acta Mathematicae Applicatae Sinica 2021年第4期37卷 847-857页

作者： Yang YANG kam Chuen YUEN Jun-feng LIU School of Statistics and Data Science Nanjing Audit UniversityNanjing211815China Department of Statistics and Actuarial Science The University of Hong KongPokfulam RoadHong KongChina

In this paper,we consider a non-standard renewal risk model with dependent claim sizes,where an insurance company is allowed to invest his/her wealth in financial assets,leading to some stochastic investment log-returns described as a general adapted càdlàg *** the assumptions that the claim sizes are heavy-tailed and the stochastic log-return process on investments is bounded from below almost surely,we derive some asymptotic formulas for the finite-time ruin probability holding uniformly in any finite time horizon.

关键词： finite-time ruin probability stochastic log-return process on investments upper tail asymptotic independence dominated variation uniformity

Joint timing and frequency synchronization in coherent optical OFDM systems

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Frontiers of Optoelectronics 2019年第1期12卷 4-14页

作者： Xinwei DU Pooi-Yuen kam Changyuan YU Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore National University of Singapore(Suzhou)Research Institute Suzhou 21512China Department of Electrical and Information Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

In this paper,we review our joint timing and frequency synchronization algorithms in coherent optical orthogonal frequency division multiplexing(CO-OFDM)*** first present a timing estimation method by designing the pattern of the training symbol,whose timing metric has a sharp and clear peak,to ensure accurate timing offset(TO)estimation *** we provide both data-aided(DA)and blind(BL)approaches to estimate the carrier frequency offset(CFO).For the DA algorithm,we utilize the same training symbol structure as the timing estimation does,while for the BL algorithm,we utilize the zero-subcarrier power(ZSP)to achieve full-range CFO *** that our joint timing and frequency synchronization approaches require only one OFDM symbol,which ensure not only the data transmission efficiency,but also the TO and CFO estimation performance.A modified BL ZSP algorithm is proposed to further improve the CFO estimation performance by taking the power average over a series of OFDM *** effectiveness of the TO estimation algorithm,and both the DA and BL CFO estimation algorithms are verified and demonstrated in both simulations and experiments.

关键词： timing offset (TO) carrier frequency offset (CFO) coherent optical orthogonal frequency division multiplexing (CO-OFDM) zero-subcarrier power (ZSP)

Enriched reproducing kernel particle method for fractional advection–diffusion equation

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Acta Mechanica Sinica 2018年第3期34卷 515-527页

作者： Yuping Ying Yanping Lian Shaoqiang Tang Wing kam Liu Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics College of Engineering Peking University Department of Mechanical Engineering Northwestern University HEDPS CAPT and LTCS Peking University

The reproducing kernel particle method （RKPM） has been efficiently applied to problems with large deformations, high gradients and high modal density. In this paper, it is extended to solve a nonlocal problem modeled by a fractional advectiondiffusion equation （FADE）, which exhibits a boundary layer with low regularity. We formulate this method on a moving least-square approach. Via the enrichment of fractional-order power functions to the traditional integer-order basis for RKPM, leading terms of the solution to the FADE can be exactly reproduced, which guarantees a good approximation to the boundary layer. Numerical tests are performed to verify the proposed approach.

关键词： Meshfree method Fractional calulus Enriched reproducing kernel Advection-diffusion equation Fractional-order basis

TRANSFECTION AND CELL FUSION BY FEMTOSECOND LASERS

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Journal of Innovative Optical Health Sciences 2011年第2期4卷 113-125页

作者： HAO HE SIU KAI KONG kam TAI CHAN Department of Electronic Engineering The Chinese University of Hong Kong ShatinN.T.Hong Kong Department of Biochemistry The Chinese University of Hong Kong ShatinN.T.Hong Kong

Biophotonics is an exciting and fast-expanding frontier which involves the fusion of advanced photonics and *** has not only created many novel methodologies for biomedical research,but also achieved many significant results as an *** to femtosecond(fs)laser technologies,important progresses have been made regarding the manipulation,imaging,and engineering of biological samples ranging from single molecules to tissues in the last 20 *** ultrashort pulses at near-infrared band provide many advantages:high nonlinear efficiency,low absorption by biological samples,high spatial and temporal resolution and confinement,and low *** are noninvasive and easy to *** the mechanism of how fs laser pulses interact with cells remains unclear,experimental results have shown that they could open up the cell membrane and hence made optical transfection and optical cell fusion *** this review,some of the seminal works on transfection and cell fusion by fs lasers are *** ideas behind and the experimental details will be described together with a highlight on their ***,the thermal effect is analyzed based on multiphoton excitation and plasma formation in an aqueous environment to explain the nontoxic characteristic of fs laser ***,some applications of fs laser induced transfection and cellcell fusion with potential major impact in biomedical sciences are proposed.

关键词： Biophotonics transfection cell fusion femtosecond laser