Minimum transport-driven algorithm for water distribution network partitioning

Abstract This paper presents a novel algorithm driven by the minimization of the transport function for the partitioning of water distribution networks (WDNs) into district metered areas (DMAs). The algorithm is based on the linear programming (LP) embedded inside a multi-objective genetic algorithm, which enables engineering criteria, such as the minimization of the boundary pipes and the maximization of the uniformity of DMAs, to be considered in the partitioning. Furthermore, the application of the algorithm on the dual network topology based on segments and valves guarantees that configurations of DMAs that respect the real positions of isolation valves for WDN partitioning are obtained. After being described on a small WDN, it is successfully validated on a large size WDN, proving better performance than other algorithms in the scientific literature for the generation of engineeringly appealing DMA configurations, with almost identical hydraulic performance to the unpartitioned WDN

Improving the resilience of post-disaster water distribution systems using a dynamic optimization framework

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Improving the resilience of water distribution systems (WDSs) to handle natural disasters (e.g., earthquakes) is a critical step towards sustainable urban water management. This requires the water utility to be able to respond quickly to such disaster events and in an organized manner, to prioritize the use of available resources to restore service rapidly whilst minimizing the negative impacts. Many methods have been developed to evaluate the WDS resilience, but few efforts are made so far to improve resilience of a post-disaster WDS through identifying optimal sequencing of recovery actions. To address this gap, a new dynamic optimization framework is proposed here where the resilience of a post-disaster WDS is evaluated using six different metrics. A tailored Genetic Algorithm is developed to solve the complex optimization problem driven by these metrics. The proposed framework is demonstrated using a real-world WDS with 6,064 pipes. Results obtained show that the proposed framework successfully identifies near-optimal sequencing of recovery actions for this complex WDS. The gained insights, conditional on the specific attributes of the case study, include: (i) the near-optimal sequencing of recovery strategy heavily depends on the damage properties of the WDS, (ii) replacements of damaged elements tend to be scheduled at the intermediate-late stages of the recovery process due to their long operation time, and (iii) interventions to damaged pipe elements near critical facilities (e.g., hospitals) should not be necessarily the first priority to recover due to complex hydraulic interactions within the WDS

Prevalence of allergic rhinitis among adults in urban and rural areas of China : a population-based cross-sectional survey

Purpose: The aim of the present study was to compare the prevalence of self-reported and confirmable allergic rhinitis (AR) with positive skin prick test (SPT) results among adults living in urban and rural areas of China. Methods: Adults from a community in Beijing and a village in Baoding were selected as representative urban and rural dwellers, respectively. All eligible residents were enrolled from the population register and received a face-to-face interview using modified validated questionnaires. Equal sets of randomly selected self-reporting AR-positive and AR-negative participants who responded to the questionnaires were also investigated using skin prick tests. Results: A total of 803 participants in the rural area and a total of 1,499 participants in the urban area completed the questionnaires, with response rates being 75.9% and 81.5% respectively. The prevalence of self-reported AR of the rural area (19.1%) was significantly higher than that of the urban area (13.5%). The elementary school of educational level increased the risk of having AR (adjusted OR=2.198, 95% CI=1.072-2.236). The positive SET rates among subjects with self-reported AR in the rural and urban areas were 32.5% and 53.3%, respectively; the confirmable AR prevalence of 6.2% and 7.2% among the rural and urban adults, respectively. Conclusions: The prevalence of confirmable AR is similar between rural and urban areas in China, although there is a higher prevalence of self-reported AR in the former

Noncrossover Dither Creeping Mutation-Based Genetic Algorithm for Pipe Network Optimization

Ceylon [Sri Lanka]ColorVolume 9, Page 1

Comparison of bypass surgery and drug-eluting stenting in diabetic patients with left main and/or multivessel disease: A systematic review and meta-analysis of randomized and nonrandomized studies

Background: With advances in theinterventional field, the choice between coronary artery bypass grafting (CABG) and percutaneous coronary intervention with drug-eluting stents (PCI-DES) for the diabetic subset with left main (LM) and/or multivessel disease (MVD) remains consistently controversial. Methods and results: We conducted a systematic review of randomized controlled trials (RCTs) and observational controlled trials (OCTs) comparing the two strategies for the diabetic subset with LM and/or MVD. PubMed, EMBASE, CENTRAL databases, Google Scholar and SinoMed were systematically searched for eligible studies without language and publica­tion restrictions. We identified 19 trials (4 randomized and 15 nonrandomized), enrolling 5,805 patients in OCTs and 3,060 patients in RCTs, respectively. PCI-DES was associated with higher mortality compared with CABG (11.7% DES vs. 9.1% CABG, RR 1.23, 95% CI 1.00–1.53, p = 0.06). Patients after PCI-DES had higher prevalence of myocardial infarction (MI) when compared with CABG (8.5% DES vs. 4.6% CABG, RR 1.68, 95% CI 1.20–2.37, p = 0.003). PCI-DES patients were at substantially lower risk of stroke (2.0% DES vs. 3.9% CABG, RR 0.51, 95% CI 0.39–0.67, p < 0.00001), but at several-fold higher risk of repeat revascularization (19.0% DES vs. 6.3% CABG, RR 2.95, 95% CI 2.46–3.55, p < 0.00001). The OCT patients risked a lower mortality as compared to the RCT patients (9.6% OCTs vs. 11.9% RCTs, RR 0.81, 95% CI 0.71–0.92, p = 0.001). Conclusions: CABG for patients with diabetes mellitus and LM and/or MVD had advan­tages over PCI-DES in all-cause death, nonfatal MI, and repeat revascularization, but the substantial disadvantage in nonfatal stroke. The high-selected patients (RCTs) risked a higher mortality than the real-world patients (OCTs)

Preparation and imaging of intravascular high-frequency transducer

Intravascular ultrasound (IVUS) imaging is by far the most favorable imaging modality for coronary artery evaluation. IVUS transducer design and fabrication, a key technology for intravascular ultrasound imaging, has a significant impact on the performance of the imaging results. Herein, a 35-MHz side-looking IVUS transducer probe was developed. With a small aperture of 0.40 mm × 0.40 mm, the transducer exhibited a very wide -6 dB bandwidth of 85% and a very low insertion loss of -12 dB. Further, the in vitro IVUS imaging of a porcine coronary artery was performed to clearly display the vessel wall structure while the corresponding color-coded graph was constructed successfully to distinguish necrotic core and fibrous plaque via image processing. The results demonstrated that the imaging performance of the optimized design transducer performs favorably