An optimization framework for modeling and simulation of dynamic systems based on AIS

Modeling and simulation can be used in many contexts for gaining insights into the functioning, performance, and operation, of complex systems. However, this method alone often produces feasible solutions under certain operating conditions of a system in which such solutions may not be optimal. This is inevitably inadequate in circumstances where optimality is required. In this respect, an approach to effectively evaluate and optimize system performance is to couple the simulation model with operations research techniques. In this paper, an optimization framework consisting of a simulation model and an immunity-inspired algorithm is proposed for optimizing the key parameters in the domain of automatic material handling.postprintThe 18th IFAC World Congress (IFAC 2011), Milano, Italy, 28 August-2 September 2011. In Conference Proceedings, 2011, p. 11608-1161

Lay personality knowledge and dispositionist thinking: A knowledge-activation framework

We explicate a knowledge-activation framework depicting the link between lay personality knowledge and dispositional judgments, building on work by Dweck, Chiu, and Hong (1995a, 1995b). According to this framework, most people possess knowledge consistent with an entity theory (personality is fixed) and incremental theory (personality is malleable), which operates according to knowledge-activation principles. Consistent with this claim, we find that people render more confident dispositional judgments when their entity knowledge is made relatively more accessible through priming manipulations that activate aspects of their existing knowledge. Findings also illustrate the usefulness of incorporating both specific and general knowledge in our analysis. The present framework enhances and complements the individual-differences approach to the study of person theories prevalent in the literature. © 2005 Elsevier Inc. All rights reserved.postprin

The Prevalence and Risk Factors of Paternal Depression from the Antenatal to the Postpartum period and the Relationships between Antenatal and Postpartum Depression among Fathers in Hong Kong

Introduction. Despite the fact that maternal perinatal mental health problems have been extensively studied and addressed to be a significant health problem, the literature on paternal perinatal mental health problems is relatively scarce. The present study aims at determining the prevalence of paternal perinatal depression and identifying the risk factors and the relationship between antenatal and postpartum depression. Methodology. 622 expectant fathers were recruited from regional maternal clinics. The expectant fathers were assessed using standardized and validated psychological instruments on 3 time points including early pregnancy, late pregnancy, and six weeks postpartum. Results. Results showed that a significant proportion of expectant fathers manifested depressive symptoms during the perinatal period. Paternal antenatal depression could significantly predict higher level of paternal postpartum depression. Psychosocial risk factors were consistently associated with paternal depression in different time points. Conclusions. The present study points to the need for greater research and clinical attention to paternal depression given that it is a highly prevalent problem and could be detrimental to their spouse and children development. The present findings contribute to theoretical basis of the prevalence and risk factors of paternal perinatal depression and have implications of the design of effective identification, prevention, and interventions of these clinical problems.published_or_final_versio

Game theoretical multi-agent modelling of coalition formation for multilateral trades

In recent years, electric utility industries worldwide have been undergoing deregulation to introduce competitiveness in the generation, transmission and distribution of electric power. The once centralised system planning and operation management must be remodelled to adapt to the new market structure. In particular, the trading mechanism needs to be totally revised as any party may now get involved in this free-market, subject to the unavoidable constraints such as generation volumes, physical transmission means and days-ahead scheduling. This paper presents a multi-agent model in conjunction with game theory to resolve the coalition formation for multilateral trades. The authors have implemented the model using the Java language and the JATLite/JAT0.3 agent development tools developed by Stanford University.published_or_final_versio

A New Optimization Cost Model for VLSI Standard Cell Placement

In this paper, we propose a new optimization cost model for VLSI placement. It distinguishes itself from the traditional wire-length cost model by having direct impact on the quality of the detailed routing phase. We also extend the well-known simulated annealing standard cell placement algorithm by applying our new cost model. Experimental results show that we got 13% layout area reduction compared to traditional wire length model, 11% reduction to commercial tool.published_or_final_versio

Ultraviolet f→f emission and crystal field analysis for Er3+ in Cs2NaErCl6

Luminescence is reported from the 2I11/2 level of Er3+, in the cubic elpasolite lattices Cs2NaErCl6 and Cs2NaYCl6. Altogether, with the use of ultraviolet laser excitation, 11 transitions from 2I11/2 Γ7 (at 40 668 cm-1) to lower term multiplets have been observed and assigned. Transitions are also reported from the 2K13/2 Γ6 level at 32 613 cm-1. The absence of emission from 2P3/2 (at 31 367 cm-1) under the experimental conditions is rationalized. Up-conversion to 2H(2)9/2, which is not due to two-photon absorption, is reported for Cs2NaErCl6 under blue pulsed laser excitation. Trap emission from 2G9/2 defect sites has been observed under ultraviolet excitation. A preliminary investigation has been made of the electronic absorption spectra of Cs2NaErCl6 and 58 Kramers quartet and doublet levels have been assigned, with a further 18 levels uncertain. The energy-level fit to 58 levels with total degeneracy 180 has been performed with a mean deviation of 20.4 cm-1, which is improved to 16.8 cm-1 if an empirical correction to the diagonal reduced matrix element of U4 for the 2H(2) term is included. The average error is similar for the 18 uncertain levels (total degeneracy 52). A comparison is included with the energy-level parametrizations of other Er3+ systems.published_or_final_versio

A double-track greedy channel routing algorithm

published_or_final_versio

Characterization of Two-Pore Channel 2 by Nuclear Membrane Electrophysiology

Lysosomal calcium (Ca2+) release mediated by NAADP triggers signalling cascades that regulate many cellular processes. The identification of two-pore channel 2 (TPC2) as the NAADP receptor advances our understanding of lysosomal Ca2+ signalling, yet the lysosome is not amenable to traditional patch-clamp electrophysiology. Previous attempts to record TPC2 single-channel activity put TPC2 outside its native environment, which not reflect TPC2’s true physiological properties. To test the feasibility of using nuclear membrane electrophysiology for TPC2 channel characterization, we constructed a stable human TPC2-expressing DT40TKO cell line that lacks endogenous InsP3R and RyR (DT40TKO-hTPC2). Immunostaining revealed hTPC2 expression on the ER and nuclear envelope. Intracellular dialysis of NAADP into Fura-2-loaded DT40TKO-hTPC2 cells elicited cytosolic Ca2+ transients, suggesting that hTPC2 was functionally active. Using nuclear membrane electrophysiology, we detected a ~220 pS single-channel current activated by NAADP with K+ as the permeant ion. The detected single-channel recordings displayed a linear current-voltage relationship, were sensitive to Ned-19 inhibition, were biphasically regulated by NAADP concentration, and regulated by PKA phosphorylation. In summary, we developed a cell model for the characterization of the TPC2 channel and the nuclear membrane patch-clamp technique provided an alternative approach to rigorously investigate the electrophysiological properties of TPC2 with minimal manipulation.published_or_final_versio

A multi-agent approach to the deregulation and restructuring of power industry

In recent years, the electric utility industry throughout the world has been facing pressure to deregulate or restructure in order to increase its efficiency, to reduce operational costs or to give consumers more alternatives. The once centralized system planning and operation management must be remodelled to adapt to the new market environment. Subject to unavoidable constraints such as the capacity of generation stations, physical limitations of the transmission lines, and demand on days-ahead scheduling, the current trading mechanism needs to be revised so that any party can be involved in this free-market environment. The paper presents a multi-agent approach to resolve the multilateral trading problem. The authors have implemented a prototype based on bilateral Shapley value and Internet technologies. The prototype has been tested with a classical six-bus system.published_or_final_versio

Contributors to Surgical In-patient Satisfaction—Development and Reliability of a Targeted Instrument

ObjectivePatient satisfaction is an important indicator of healthcare system performance. High patient satisfaction is associated with greater trust in caregivers, improved compliance with treatment recommendations and a better quality of life (QOL). There are few validated instruments to measure surgical patients' satisfaction. The aim of this study was to develop a culturally-specific patient satisfaction instrument, for use as an outcome measure in evaluating surgical services.DesignPatient focus groups were convened to explore dimensions of the peri-operative hospital experience. Forums uncovered pertinent domains of interest and identified terminology understood by patients. A preliminary set of items reflecting patient satisfaction was developed. Test-retest reliability of a new surgical patient satisfaction instrument was assessed in 42 subjects at hospital discharge.ResultsDomains that emerged included; admission processes and hospital environment, information provision, nursing care, doctor and nurse interaction, and ancillary staff services. Staff attitudes and human qualities were highly valued, as was prompt attention to requests for assistance. Clarity or quality of medical information did not appear to influence in-patient satisfaction. A new measure of surgical patient satisfaction, Hong Kong Index of Inpatient Happiness (HK2Happ), was developed from focus group consultation. Test-retest generated an Intra Class Correlation of 0.868–0.935, indicating a highly stable tool.ConclusionsThe initial version of HK2Happ was reliable in assessing surgical patient satisfaction. The measure is now undergoing validity testing across different surgical patient populations for generalisation and generation of a short form of discriminant items