205 research outputs found
Flood Damage Assessment in Taipei City Taiwan
In this study, we reviewed the literature on flood damage assessment and collected information for related research in Taiwan to analyze the relationships between direct flood damage, flood frequency, flood depth, and land-use. The procedure for flood damage assessment was then developed that includes the following steps: (a) Scenario simulation of inundation potential. (b) Establishment of the relationship between inundation depth and damage loss for varied land-use. (c) Risk analysis of inundation damage.
Taipei City in north Taiwan was adopted as the case study to demonstrate the proposed algorithm. Flood events with return periods of 5, 10, 25, 50, 100 and 200 years were used for flood hazard analysis to cover possible flooding scenarios. The inundation hazard maps were first generated via hydraulic modelling. The regional flood damage was then estimated using a relationship between inundation depth and damage. The flood damage exceedance probability (EP) curve for Taipei City was constructed following the association of the loss with its probability of occurrence. The flood damage EP curve was further used to integrate the damage assessments for individual flood events for a full probability range presentation of the flood risk. The expected annual damage was calculated by integrating the area under the EP curve
Flood Vulnerability and Risk Maps in Taipei City, Taiwan
This paper presents the process of constructing a flood risk map in Taipei City. The study calculates the social vulnerability index (SVI) for flooding at a district level, based on five factors including (1) female population (2) alone living elderly (3) low-income households (4) household income and (5) house-hold possessions. The index is determined according to the factor ratios in a district comparing to the statistical average across Taipei City. By combining the SVI with spatial varied flood potential information simulated by a hydraulic model, the flood risk index is obtained for district level that has an area of about 0.2 km2. Results show that the flood risk in Taipei City changed from 2002 to 2010 due to changes in the demographic structure. During the period from 2002 to 2004, the most obvious change of flood risk occurred in the Wanhua district due to the increase in the ratio of household possessions, which escalated the vulnerability to flooding. Between 2005 and 2007, the ratio of household possessions dropped in the Nankang district such that the flood risk reduced mostly in the region
Novel Catalysts and Processing Technologies for Production of Aerospace Fuels from Non-Petroleum Raw Materials
Transportation fuels production (including aerospace propellants) from non-traditional sources (gases, waste materials, and biomass) has been an active area of research and development for decades. Reducing terrestrial waste streams simultaneous with energy conversion, plentiful biomass, new low-cost methane sources, and/or extra-terrestrial resource harvesting and utilization present significant technological and business opportunities being realized by a new generation of visionary entrepreneurs. We examine several new approaches to catalyst fabrication and new processing technologies to enable utilization of these nontraditional raw materials. Two basic processing architectures are considered: a single-stage pyrolysis approach that seeks to basically re-cycle hydrocarbons with minimal net chemistry or a two-step paradigm that involves production of supply or synthesis gas (mainly carbon oxides and H2) followed by production of fuel(s) via Sabatier or methanation reactions and/or Fischer-Trpsch synthesis. Optimizing the fraction of product stream relevant to targeted aerospace (and other transportation) fuels via modeling, catalyst fabrication and novel reactor design are described. Energy utilization is a concern for production of fuels for either terrestrial or space operations; renewable sources based on solar energy and/or energy efficient processes may be mission enabling. Another important issue is minimizing impurities in the product stream(s), especially those potentially posing risks to personnel or operations through (catalyst) poisoning or (equipment) damage. Technologies being developed to remove (and/or recycle) heteroatom impurities are briefly discussed as well as the development of chemically robust catalysts whose activities are not diminished during operation. The potential impacts on future missions by such new approaches as well as balance of system issues are addressed
Effect of positive end-expiratory pressure and tidal volume on lung injury induced by alveolar instability
Probing flavor changing interactions in hadron collisions
The subprocess in the two-Higgs-doublet model with
flavor-changing scalar couplings is examined at the one loop level. With
perturbative QCD factorization theorem, the corresponding cross sections for
hadron-hadron collisions are computed numerically. The results are applicable
to the whole mass range of the weakly coupled Higgs bosons. In case we could
efficiently exclude the severe backgrounds of the
production signal, probing the flavor-changing top-charm-scalar vertex at
hadron colliders would be very promising and accessible experimentally.Comment: LaTex file, 14 pages, 8 EPS figure
Atrial Fibrillation and the Prognostic Performance of Biomarkers in Heart Failure
BACKGROUND: Consideration of circulating biomarkers for risk stratification in heart failure (HF) is recommended, but the influence of atrial fibrillation (AF) on prognostic performance of many markers is unclear. We investigated the influence of AF on the prognostic performance of circulating biomarkers in HF. METHODS: N-terminal pro-B-type natriuretic peptide (NT-proBNP), mid-regional-pro-atrial natriuretic peptide, C-type natriuretic peptide (CNP), NT-proCNP, high-sensitivity troponin-T, high-sensitivity troponin-I, mid-regional-propeptide adrenomedullin, co-peptin, growth differentiation factor-15, soluble Suppressor of Tumorigenicitiy (sST2), galectin-3, and procalcitonin plasma concentrations were measured in a prospective, multicenter study of adults with HF. AF was defined as a previous history of AF, and/or presence of AF/flutter on baseline 12-lead electrocardiogram. The primary outcome was the composite of HF-hospitalization or all-cause mortality at 2 years. RESULTS: Among 1099 patients (age 62 +/- 12years, 28% female), 261(24%) patients had AF. Above-median concentrations of all biomarkers were independently associated with increased risk of the primary outcome. Significant interactions with AF were detected for galectin-3 and sST2. In considering NT-proBNP for additive risk stratification, sST2 (adjusted hazard ratio [AHR]1.85, 95%confidence interval [C.I.] 1.17-2.91) and galectin-3 (AHR1.85, 95%C.I. 1.09-2.45) were independently associated with increased primary outcome only in the presence of AF. The prognostic performance of sST2 was also stronger in AF for all-cause mortality (AF: AHR2.82, 95%C.I. 1.26-6.21; non-AF: AHR1.78, 95% C.I. 1.14-2.76 without AF), while galectin-3 predicted HF-hospitalization only in AF (AHR1.64, 95%C.I. 1.03-2.62). CONCLUSIONS: AF modified the prognostic utility of selected guideline-endorsed HF-biomarkers. Application of markers for prognostic purposes in HF requires consideration of the presence or absence of AF
Multi-Scale Stellar Associations across the Star Formation Hierarchy in PHANGS-HST Nearby Galaxies: Methodology and Properties
We develop a method to identify and determine the physical properties of
stellar associations using Hubble Space Telescope (HST) NUV-U-B-V-I imaging of
nearby galaxies from the PHANGS-HST survey. We apply a watershed algorithm to
density maps constructed from point source catalogues Gaussian smoothed to
multiple physical scales from 8 to 64 pc. We develop our method on two galaxies
that span the distance range in the PHANGS-HST sample: NGC 3351 (10 Mpc), NGC
1566 (18 Mpc). We test our algorithm with different parameters such as the
choice of detection band for the point source catalogue (NUV or V), source
density image filtering methods, and absolute magnitude limits. We characterise
the properties of the resulting multi-scale associations, including sizes,
number of tracer stars, number of associations, photometry, as well as ages,
masses, and reddening from Spectral Energy Distribution fitting. Our method
successfully identifies structures that occupy loci in the UBVI colour-colour
diagram consistent with previously published catalogues of clusters and
associations. The median ages of the associations increases from log(age/yr) =
6.6 to log(age/yr) = 6.9 as the spatial scale increases from 8 pc to 64 pc for
both galaxies. We find that the youngest stellar associations, with ages < 3
Myr, indeed closely trace H ii regions in H imaging, and that older
associations are increasingly anti-correlated with the H emission.
Owing to our new method, the PHANGS-HST multi-scale associations provide a far
more complete census of recent star formation activity than found with previous
cluster and compact association catalogues. The method presented here will be
applied to the full sample of 38 PHANGS-HST galaxies.Comment: Submitted to MNRAS. Referee report received with minor comments, and
"request to clarify if the smaller associations are always included in the
larger ones and how this may affect the photometric fitting of the larger
association if the groups have different ages." Revision in progres
Automated interpretation of systolic and diastolic function on the echocardiogram:a multicohort study
Background: Echocardiography is the diagnostic modality for assessing cardiac systolic and diastolic function to diagnose and manage heart failure. However, manual interpretation of echocardiograms can be time consuming and subject to human error. Therefore, we developed a fully automated deep learning workflow to classify, segment, and annotate two-dimensional (2D) videos and Doppler modalities in echocardiograms. Methods: We developed the workflow using a training dataset of 1145 echocardiograms and an internal test set of 406 echocardiograms from the prospective heart failure research platform (Asian Network for Translational Research and Cardiovascular Trials; ATTRaCT) in Asia, with previous manual tracings by expert sonographers. We validated the workflow against manual measurements in a curated dataset from Canada (Alberta Heart Failure Etiology and Analysis Research Team; HEART; n=1029 echocardiograms), a real-world dataset from Taiwan (n=31 241), the US-based EchoNet-Dynamic dataset (n=10 030), and in an independent prospective assessment of the Asian (ATTRaCT) and Canadian (Alberta HEART) datasets (n=142) with repeated independent measurements by two expert sonographers. Findings: In the ATTRaCT test set, the automated workflow classified 2D videos and Doppler modalities with accuracies (number of correct predictions divided by the total number of predictions) ranging from 0·91 to 0·99. Segmentations of the left ventricle and left atrium were accurate, with a mean Dice similarity coefficient greater than 93% for all. In the external datasets (n=1029 to 10 030 echocardiograms used as input), automated measurements showed good agreement with locally measured values, with a mean absolute error range of 9–25 mL for left ventricular volumes, 6–10% for left ventricular ejection fraction (LVEF), and 1·8–2·2 for the ratio of the mitral inflow E wave to the tissue Doppler e' wave (E/e' ratio); and reliably classified systolic dysfunction (LVEF <40%, area under the receiver operating characteristic curve [AUC] range 0·90–0·92) and diastolic dysfunction (E/e' ratio ≥13, AUC range 0·91–0·91), with narrow 95% CIs for AUC values. Independent prospective evaluation confirmed less variance of automated compared with human expert measurements, with all individual equivalence coefficients being less than 0 for all measurements. Interpretation: Deep learning algorithms can automatically annotate 2D videos and Doppler modalities with similar accuracy to manual measurements by expert sonographers. Use of an automated workflow might accelerate access, improve quality, and reduce costs in diagnosing and managing heart failure globally. Funding: A*STAR Biomedical Research Council and A*STAR Exploit Technologies
- …