Application of wavelet transform to steady-state approximation of power electronics waveforms

Author name used in this publication: Chi K. TseRefereed conference paper2002-2003 > Academic research: refereed > Refereed conference paperVersion of RecordPublishe

Synthesis and Bactericidal Ability of TiO2 and Ag-TiO2 Prepared by Coprecipitation Method

Preparation of photocatalysts of TiO2 and Ag-TiO2 was carried out by coprecipitation method. The prepared photocatalysts were characterized by X-ray diffraction (XRD), SEM, EDX, and XRF analysis. The disinfection of E. coli, a model indicator organism for the safe water supply, was investigated by using TiO2 and Ag-TiO2 under different light sources. The treatment efficacy for the inactivation of E. coli would be UV/Ag-TiO2; visible/Ag-TiO2; dark/Ag-TiO2; UV (all 100%) \u3e UV/TiO2 (99%) \u3e visible/TiO2 (96%) \u3e dark/TiO2 (87%) \u3e visible (23%) \u3e dark (19%). The order of disinfection efficiency by their corresponding kinetic initial apparent rate constants, , (min−1) would be UV/Ag-TiO2; visible/Ag-TiO2 (both 6.67) \u3e UV (6.6) \u3e dark/Ag-TiO2 (6.56) \u3e UV/TiO2 (1.62) \u3e visible/TiO2 (1.08) \u3e dark/TiO2 (0.7) \u3e visible (0.28) \u3e dark (0.03). The application of TiO2 doped with silver strongly improved the ability of disinfection treatment. The study of mineralization of E. coli by measurement of TOC (total organic carbon) removal percentage showed that the visible light may effectively be applied for the disinfection unit of water and wastewater treatment system by using photocatalysts of Ag-TiO2

Synthesis and Bactericidal Ability of TiO2 and Ag-TiO2 Prepared by Coprecipitation Method

Preparation of photocatalysts of TiO2 and Ag-TiO2 was carried out by coprecipitation method. The prepared photocatalysts were characterized by X-ray diffraction (XRD), SEM, EDX, and XRF analysis. The disinfection of E. coli, a model indicator organism for the safe water supply, was investigated by using TiO2 and Ag-TiO2 under different light sources. The treatment efficacy for the inactivation of E. coli would be UV/Ag-TiO2; visible/Ag-TiO2; dark/Ag-TiO2; UV (all 100%) \u3e UV/TiO2 (99%) \u3e visible/TiO2 (96%) \u3e dark/TiO2 (87%) \u3e visible (23%) \u3e dark (19%). The order of disinfection efficiency by their corresponding kinetic initial apparent rate constants, , (min−1) would be UV/Ag-TiO2; visible/Ag-TiO2 (both 6.67) \u3e UV (6.6) \u3e dark/Ag-TiO2 (6.56) \u3e UV/TiO2 (1.62) \u3e visible/TiO2 (1.08) \u3e dark/TiO2 (0.7) \u3e visible (0.28) \u3e dark (0.03). The application of TiO2 doped with silver strongly improved the ability of disinfection treatment. The study of mineralization of E. coli by measurement of TOC (total organic carbon) removal percentage showed that the visible light may effectively be applied for the disinfection unit of water and wastewater treatment system by using photocatalysts of Ag-TiO2

Hemodynamic changes in progressive cerebral infarction:An observational study based on blood pressure monitoring

Progressive cerebral infarction (PCI) is a common complication in patients with ischemic stroke that leads to poor prognosis. Blood pressure (BP) can indicate post‐stroke hemodynamic changes which play a key role in the development of PCI. The authors aim to investigate the association between BP‐derived hemodynamic parameters and PCI. Clinical data and BP recordings were collected from 80 patients with cerebral infarction, including 40 patients with PCI and 40 patients with non‐progressive cerebral infarction (NPCI). Hemodynamic parameters were calculated from the BP recordings of the first 7 days after admission, including systolic and diastolic BP, mean arterial pressure, and pulse pressure (PP), with the mean values of each group calculated and compared between daytime and nighttime, and between different days. Hemodynamic parameters and circadian BP rhythm patterns were compared between PCI and NPCI groups using t‐test or non‐parametric equivalent for continuous variables, Chi‐squared test or Fisher's exact test for categorical variables, Cox proportional hazards regression analysis and binary logistic regression analysis for potential risk factors. In PCI and NPCI groups, significant decrease of daytime systolic BP appeared on the second and sixth days, respectively. Systolic BP and fibrinogen at admission, daytime systolic BP of the first day, nighttime systolic BP of the third day, PP, and the ratio of abnormal BP circadian rhythms were all higher in the PCI group. PCI and NPCI groups were significantly different in BP circadian rhythm pattern. PCI is associated with higher systolic BP, PP and more abnormal circadian rhythms of BP

Ultrahigh birefringence index-guiding photonic crystal fiber and its application for pressure and temperature discrimination

2012-2013 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Organic Bulk Heterojunction Infrared Photodiodes for Imaging Out to 1300 nm

This work studies organic bulk heterojunction photodiodes with a wide spectral range capable of imaging out to 1.3 μm in the shortwave infrared. Adjustment of the donor-to-acceptor (polymer:fullerene) ratio shows how blend composition affects the density of states (DOS) which connects materials composition and optoelectronic properties and provides insight into features relevant to understanding dispersive transport and recombination in the narrow bandgap devices. Capacitance spectroscopy and transient photocurrent measurements indicate the main recombination mechanisms arise from deep traps and poor extraction from accumulated space charges. The amount of space charge is reduced with a decreasing acceptor concentration; however, this reduction is offset by an increasing trap DOS. A device with 1:3 donor-to-acceptor ratio shows the lowest density of deep traps and the highest external quantum efficiency among the different blend compositions. The organic photodiodes are used to demonstrate a single-pixel imaging system that leverages compressive sensing algorithms to enable image reconstruction

Untangling operational performance implication of ambidextrous blockchain initiatives: An empirical investigation of Chinese manufacturers

Purpose Blockchain has been considered as a disruptive technology and every industry stands to benefit from it. According to Deloitte, increasing number of managers claim that their firms will suffer loss in competitive advantage if they do not adopt blockchain. Despite this motivation, insufficient knowledge on how can blockchain add value inhibits the commitment to its adoption. To better understand the possible influence of blockchain, two dimensions (exploitation and exploration) of blockchain initiatives are distinguished. This research aims to examine the impact of ambidextrous blockchain initiatives on firms' operational efficiency, as well as the moderating role of unabsorbed slack and environmental munificence. Design/methodology/approach In this paper, secondary panel data were collected from multiple sources to test the proposed hypotheses. Content analysis was adopted to operationalise ambidextrous blockchain initiatives from firms' official announcements. Findings The authors find that firms' ambidexterity in blockchain initiatives have significantly positive impact on operational efficiency. Furthermore, when firms have lower unabsorbed slack or in more munificent environments, they may benefit from managing a balance between exploration and exploitation. Originality/value This research offers some insightful theoretical and managerial implications of ambidextrous blockchain initiatives. The findings of this study contribute to blockchain literature by providing theory-driven empirical research

Glycemic and lipid variability for predicting complications and mortality in diabetes mellitus using machine learning

Introduction Recent studies have reported that HbA1c and lipid variability is useful for risk stratification in diabetes mellitus. The present study evaluated the predictive value of the baseline, subsequent mean of at least three measurements and variability of HbA1c and lipids for adverse outcomes. Methods This retrospective cohort study consists of type 1 and type 2 diabetic patients who were prescribed insulin at outpatient clinics of Hong Kong public hospitals, from 1st January to 31st December 2009. Standard deviation (SD) and coefficient of variation were used to measure the variability of HbA1c, total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglyceride. The primary outcome is all-cause mortality. Secondary outcomes were diabetes-related complications. Result The study consists of 25,186 patients (mean age = 63.0, interquartile range [IQR] of age = 15.1 years, male = 50%). HbA1c and lipid value and variability were significant predictors of all-cause mortality. Higher HbA1c and lipid variability measures were associated with increased risks of neurological, ophthalmological and renal complications, as well as incident dementia, osteoporosis, peripheral vascular disease, ischemic heart disease, atrial fibrillation and heart failure (p <  0.05). Significant association was found between hypoglycemic frequency (p <  0.0001), HbA1c (p <  0.0001) and lipid variability against baseline neutrophil-lymphocyte ratio (NLR). Conclusion Raised variability in HbA1c and lipid parameters are associated with an elevated risk in both diabetic complications and all-cause mortality. The association between hypoglycemic frequency, baseline NLR, and both HbA1c and lipid variability implicate a role for inflammation in mediating adverse outcomes in diabetes, but this should be explored further in future studies