An example of expert system on numerical modelling system in coastal processes

Author name used in this publication: K. W. Chau2001-2002 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

Intelligent manipulation and calibration of parameters for hydrological models

Author name used in this publication: K. W. Chau2006-2007 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

A fifth generation numerical modelling system in coastal zone

Author name used in this publication: K. W. Chau2001-2002 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

The maximum of randomly weighted sums with long tails in insurance and finance

In risk theory we often encounter stochastic models containing randomly weighted sums. In these sums, each primary real-valued random variable, interpreted as the net loss during a reference period, is associated with a nonnegative random weight, interpreted as the corresponding stochastic discount factor to the origin. Therefore, a weighted sum of m terms, denoted as S m (w), represents the stochastic present value of aggregate net losses during the first m periods. Suppose that the primary random variables are independent of each other with long-tailed distributions and are independent of the random weights. We show conditions on the random weights under which the tail probability of max 1≤m≤n S m (w)-the maximum of the first n weighted sums-is asymptotically equivalent to that of S n (w)-the last weighted sum. © 2011 Copyright Taylor and Francis Group, LLC.postprin

Optical properties of a novel yellow fluorescent dopant for use in organic LEDs

In this paper, the optical properties of a novel organic, 2,8-di(t-butyl)-5,11-di[4(t-butyl) phenyl]-6,12-diphenylnaphthacene (tetra(t-butyl)rubrene) have been investigated. Our results show that there are two peaks in the photoluminescence (PL) spectra of tetra(t-butyl)rubrene (TBRb) which are also confirmed in the electroluminescence (EL) spectra. Photo-quenching of the PL intensity is observed when the irradiation time increases. It is shown that oxidation is the dominant reason for photo-quenching. The absolute refractive index and absorption coefficient have also been determined and the results correlate well with the PL results. The results show that TBRb can be a good dopant to achieve the Förster energy transfer and to assist light emission. The optical properties of TBRb are similar to those of rubrene; however, the PL of TBRb is much stronger than that of rubrene. Finally, although crystalline organics have been commonly reported by heating the sample, we report crystallization of TBRb at low temperature <230 K when the TBRb film is in an amorphous form before cooling. © Springer-Verlag 2004.postprin

Optical Properties of a Novel Dye in Yellow Florescent Organic LEDs

In this paper, time-resolved PL, lifetime and crystallization of a novel organic, 2,8-di(t-butyl)-5,11-di[4(t-butyl)phenyl]-6,12-diphenylnaphthacene, which is considered to be potential candidate to substitute the conventionally used 5,6,11,12-tetraphenylnaphthacene for a higher efficient yellow-color organic LED, were investigated. The PL intensity will reduce when the irradiation time increases because of photo-quenching. It is shown that oxidation is the dominant reason for photo-quenching. In addition, TBRb has two lifetimes. The short one is /spl sim/5 ns and the long one is /spl sim/31 ns. They are considerably contributed by the short PL peak and long PL peak respectively. Furthermore, we first report, to the best knowledge, crystallization of TBRb at low temperature of 11 K and with irradiation.published_or_final_versio

Acceptors in undoped gallium antimonide

Undoped GaSb materials were studied by temperature dependent Hall (TDH) measurements and photoluminescence (PL). The TDH data reveals four acceptor levels (having ionization energies of 7meV, 32meV, 89meV and 123meV) in the as-grown undoped GaSb samples. The 32meV and the 89meV levels were attributed to the GaSb defect and the VGa-related defect. The Ga Sb defect was found to be the important acceptor responsible for the p-type nature of the present undoped GaSb samples because of its abundance and its low ionization energy. This defect was thermally stable after the 500°C annealing. Similar to the non-irradiated samples, the 777meV and the 800meV PL signals were also observed in the electron irradiated undoped GaSb samples. The decrease of the two peaks' intensities with respect to the electron irradiation dosage reveals the introduction of a non-radiative defect during the electron irradiation process, which competes with the transition responsible for the 777meV and the 800meV PL peaks.published_or_final_versio

Benefit sharing for BIM implementation: Tackling the moral hazard dilemma in inter-firm cooperation

Building information modeling (BIM) plays an important role in furthering value-creation of construction projects by advocating the inter-firm cooperation. When implementing BIM, however, individual firms inherently safeguard their self-interests regardless of the fact that inter-firm cooperation might reap joint BIM benefits for a project overall, which epitomizes a typical problem of moral hazards in project-based organizations. This paper develops an outcome-linked benefit sharing model that considers sharing joint BIM benefits among stakeholders including designers, contractors, and clients for tracking moral hazards therein. By modeling stakeholders' behaviors as evolutionary games within a principal–agent formalism, it has been deducted that (1) designers/contractors could be incentivized to cooperate had each stakeholder received a share higher than the quotient of BIM costs over value-creation in the design/construction phase; and (2) how joint BIM benefits can be more than noncooperation outcomes is key for clients to support BIM implementation

Differentiation of mouse induced pluripotent stem cells (iPSCs) into nucleus pulposus-like cells in vitro.

A large percentage of the population may be expected to experience painful symptoms or disability associated with intervertebral disc (IVD) degeneration - a condition characterized by diminished integrity of tissue components. Great interest exists in the use of autologous or allogeneic cells delivered to the degenerated IVD to promote matrix regeneration. Induced pluripotent stem cells (iPSCs), derived from a patient's own somatic cells, have demonstrated their capacity to differentiate into various cell types although their potential to differentiate into an IVD cell has not yet been demonstrated. The overall objective of this study was to assess the possibility of generating iPSC-derived nucleus pulposus (NP) cells in a mouse model, a cell population that is entirely derived from notochord. This study employed magnetic activated cell sorting (MACS) to isolate a CD24(+) iPSC subpopulation. Notochordal cell-related gene expression was analyzed in this CD24(+) cell fraction via real time RT-PCR. CD24(+) iPSCs were then cultured in a laminin-rich culture system for up to 28 days, and the mouse NP phenotype was assessed by immunostaining. This study also focused on producing a more conducive environment for NP differentiation of mouse iPSCs with addition of low oxygen tension and notochordal cell conditioned medium (NCCM) to the culture platform. iPSCs were evaluated for an ability to adopt an NP-like phenotype through a combination of immunostaining and biochemical assays. Results demonstrated that a CD24(+) fraction of mouse iPSCs could be retrieved and differentiated into a population that could synthesize matrix components similar to that in native NP. Likewise, the addition of a hypoxic environment and NCCM induced a similar phenotypic result. In conclusion, this study suggests that mouse iPSCs have the potential to differentiate into NP-like cells and suggests the possibility that they may be used as a novel cell source for cellular therapy in the IVD

12-year follow-up student of mortality due to suicide among first-episode psychosis cohort: Is the early intervention program more effective in reducing excess mortality due to suicide in psychosis

Oral Presentation: O10. Treatment and clinical service: no. O10.8published_or_final_versio