A Risk-Based Decision Support System for Failure Management in Water Distribution Networks

The operational management of Water Distribution Systems (WDS), particularly under failure conditions when the behaviour of a WDS is not well understood, is a challenging problem. The research presented in this thesis describes the development of a methodology for risk-based diagnostics of failures in WDS and its application in a near real-time Decision Support System (DSS) for WDS’ operation. In this thesis, the use of evidential reasoning to estimate the likely location of a burst pipe within a WDS by combining outputs of several models is investigated. A novel Dempster-Shafer model is developed, which fuses evidence provided by a pipe burst prediction model, a customer contact model and a hydraulic model to increase confidence in correctly locating a burst pipe. A new impact model, based on a pressure driven hydraulic solver coupled with a Geographic Information System (GIS) to capture the adverse effects of failures from an operational perspective, is created. A set of Key Performance Indicators used to quantify impact, are aggregated according to the preferences of a Decision Maker (DM) using the Multi-Attribute Value Theory. The potential of distributed computing to deliver a near real-time performance of computationally expensive impact assessment is explored. A novel methodology to prioritise alarms (i.e., detected abnormal flow events) in a WDS is proposed. The relative significance of an alarm is expressed using a measure of an overall risk represented by a set of all potential incidents (e.g., pipe bursts), which might have caused it. The DM’s attitude towards risk is taken into account during the aggregation process. The implementation of the main constituents of the proposed risk-based pipe burst diagnostics methodology, which forms a key component of the aforementioned DSS prototype, are tested on a number of real life and semi-real case studies. The methodology has the potential to enable more informed decisions to be made in the near real-time failure management in WDS

A DSS generator for multiobjective optimisation of spreadsheet-based models

Copyright © 2011 Elsevier. NOTICE: this is the author’s version of a work that was accepted for publication in Environmental Modelling & Software. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Environmental Modelling & Software Vol. 26 (2011), DOI: 10.1016/j.envsoft.2010.11.004Water management practice has benefited from the development of model-driven Decision Support Systems (DSS), and in particular those that combine simulation with single or multiple-objective optimisation tools. However, there are many performance, acceptance and adoption problems with these decision support tools caused mainly by misunderstandings between the communities of system developers and users. This paper presents a general-purpose decision-support system generator, GANetXL, for developing specific applications that require multiobjective optimisation of spreadsheet-based models. The system is developed as an Excel add-in that provides easy access to evolutionary multiobjective optimisation algorithms to non-specialists by incorporating an intuitive interactive graphical user interface that allows easy creation of specific decision-support applications. GANetXL’s utility is demonstrated on two examples from water engineering practice, a simple water supply reservoir operation model with two objectives and a large combinatorial optimisation problem of pump scheduling in water distribution systems. The two examples show how GANetXL goes a long way toward closing the gap between the achievements in optimisation technology and the successful use of DSS in practice.Engineering and Physical Sciences Research Council (EPSRC

Pipe burst diagnostics using evidence theory

Copyright © IWA Publishing 2011.The definitive peer-reviewed and edited version of this article is published in Journal of Hydroinformatics Volume 13 Issue 4, pp. 596–608 (2011), DOI: 10.2166/hydro.2010.201 and is available at www.iwapublishing.com.This paper presents a decision support methodology aimed at assisting Water Distribution System (WDS) operators in the timely location of pipe bursts. This will enable them to react more systematically and promptly. The information gathered from various data sources to help locate where a pipe burst might have occurred is frequently conflicting and imperfect. The methodology developed in this paper deals effectively with such information sources. The raw data collected in the field is first processed by means of several models, namely the pipe burst prediction model, the hydraulic model and the customer contacts model. The Dempster–Shafer Theory of Evidence is then used to combine the outputs of these models with the aim of increasing the certainty of determining the location of a pipe burst within a WDS. This new methodology has been applied to several semi-real case studies. The results obtained demonstrate that the method shows potential for locating the area of a pipe burst by capturing the varying credibility of the individual models based on their historical performance

Intelligent urban water infrastructure management

Copyright © 2013 Indian Institute of ScienceUrban population growth together with other pressures, such as climate change, create enormous challenges to provision of urban infrastructure services, including gas, electricity, transport, water, etc. Smartgrid technology is viewed as the way forward to ensure that infrastructure networks are fl exible, accessible, reliable and economical. “Intelligent water networks” take advantage of the latest information and communication technologies to gather and act on information to minimise waste and deliver more sustainable water services. The effective management of water distribution, urban drainage and sewerage infrastructure is likely to require increasingly sophisticated computational techniques to keep pace with the level of data that is collected from measurement instruments in the field. This paper describes two examples of intelligent systems developed to utilise this increasingly available real-time sensed information in the urban water environment. The first deals with the failure-management decision-support system for water distribution networks, NEPTUNE, that takes advantage of intelligent computational methods and tools applied to near real-time logger data providing pressures, flows and tank levels at selected points throughout the system. The second, called RAPIDS, deals with urban drainage systems and the utilisation of rainfall data to predict flooding of urban areas in near real-time. The two systems have the potential to provide early warning and scenario testing for decision makers within reasonable time, this being a key requirement of such systems. Computational methods that require hours or days to run will not be able to keep pace with fast-changing situations such as pipe bursts or manhole flooding and thus the systems developed are able to react in close to real time.Engineering and Physical Sciences Research CouncilUK Water Industry ResearchYorkshire Wate

Fat-pad impingement after total knee arthroplasty with the LCS A/P-Glide system

Early follow-up (15.8 months;1-48) of 230 knee replacements with an LCS A/P Glide component indicated an increased occurrence of anterior knee pain due to a fat-pad impingement, necessitating early revision surgery. Unsatisfactory results were observed in 28 knees (12.2%). Thirteen knees (5.7%) were revised on finding the fat-pad impingement, and four knees (1.7%) were scheduled for later revision surgery; the remaining 11 subjects (4.8%) had revision surgery for a different reason. Twenty-six subjects (11.3%) complained about milder but typical symptoms of a fat-pad impingement, and 22 subjects (9.6%) had unspecific mild symptoms. 151 knees (65.7%) were free of pain and demonstrated an excellent result. The total revision rate of 10.4% (24 knees) is higher than described for other implant systems. However, the revision needed to treat the fat-pad impingement (5.7%) consisted of minor surgery only, such as exchange of the mobile bearing or reduction of the fat pad by arthroscopy. The femoral and tibial components were able to be left untouched. Resection of the Hoffa's fat pad is recommended when such an implant system is used, and possible impingement should be investigated intraoperatively before closur

Hastaların perspektifinden: Periton diyalizinin yaşama ve ruhsal belirtilere etkisi

Amaç: Bu çalışmanın amacı; sürekli ayaktan periton diyalizi (SAPD) uygulayan hastaların kendi ifadeleri ile hastalığı nasıl tanımladıkları ve periton diyalizinin iş, aile, sosyal ve özel yaşamlarına etkisi ile ruhsal belirti sıklığı arasındaki ilişkileri incelemektir. Yöntem: Tanımlayıcı ve ilişki arayıcı olarak yapılan bu çalışma özel bir diyaliz merkezinde takip edilen 153 periton diyalizi hastasıyla yürütülmüştür. Çalışma verileri hasta tanıtım formu ve Kısa Semptom Envanteri (KSE) kullanılarak toplanmıştır. Bulgular: Hastaların yaş ortalaması 49.51±15.44 yıl olup, %53.6’sı erkektir. Hastaların %81.7’si evli ve %51.6’sı ilkokul mezunudur. Hastaların %18.3’ü “hastalığın doğal bir durum” olduğunu ve %46.6’sı “özel yaşamında hiçbir şeyin eskisi gibi olmadığını, daha karmaşık ve zor olduğunu” belirtmiştir. KSE puan ortalaması 49.01±13.21 olarak bulunmuştur. Periton diyalizinin iş yaşamlarını nasıl etkilediğine ilişkin ifadeleri açısından, KSE’nin somatik belirtiler, hostilite ve paranoid düşünceler alt boyutları arasında istatistiksel olarak anlamlı fark bulunmuştur (p<.01, p<.01 ve p<.05). Sonuç: Periton diyalizi hastaları yaş, cinsiyet, hastalıklarını algılayış biçimleri ve hastalığın yaşamlarını etkileme biçimlerine göre değişik sıklıkta ruhsal belirtiler yaşayabilmektedir

Outcome analysis in patients with metastatic gastroenteropancreatic neuroendocrine tumors receiving peptide receptor radionuclide therapy with Lu-177-DOTATATE

BACKGROUND Patients with neuroendocrine tumors (NET) of the gastroenteropancreatic tract (GEP-NET) were effectively treated with peptide receptor radionuclide therapy (PRRT) with Lu-177-DOTATATE in the NETTER-1 trial. The aim of this study was to assess the outcome of metastatic GEP-NET patients within a European Neuroendocrine Tumor Society (ENETS) certified center of excellence after this treatment. METHODS A total of 41 GEP-NET patients who received PRRT with Lu-177-DOTATATE between 2012 and 2017 at a single center were included in this analysis. Data on pre- and post-PRRT treatments [selective internal radiation therapy (SIRT), somatostatin analogue therapy (SSA), blood parameters, patient symptomatic burden and overall survival] was extracted from patient records. RESULTS Overall, PRRT was well tolerated and did not increase patient symptomatic burden. Blood parameters were not significantly affected by PRRT (means before and after therapy: hemoglobin: 125.4 vs. 122.3 mg/L, P=0.201; creatinine: 73.8 vs. 77.7 µmol/L, P=0.146), while leukocytes (6.6 vs. 5.6 G/L, P<0.01) and platelets (269.9 vs. 216.7 G/L, P<0.001) were significantly decreased yet without clinical significance in our study. Seven of 9 patients with SIRT treatment prior to PRRT were deceased (mortality odds ratio =4.083). The mortality odds ratio of patients with a pancreatic tumor and SIRT was 1.33 compared to patients with a different tumor origin. 6 of 15 patients (40%) with post-PRRT SSA were deceased (mortality odds ratio =0.429 without SSA after PRRT). CONCLUSIONS Patients with advanced GEP-NET might benefit from PRRT with Lu-177-DOTATATE as it can provide a valuable treatment modality in advanced disease stages. Safety profiles of PRRT were manageable without increasing the symptomatic burden. SIRT before PRRT or lack of SSA after PRRT seem to impair the response and reduce survival

A descriptive analysis of the characteristics, treatment response and prognosis of hepatic dominant solid tumors undergoing selective internal radiation therapy (SIRT)

BACKGROUND Selective internal radiotherapy is widely used for liver dominant diseases of solid tumors. However, data about sequential treatment and prognostic factors are lacking. METHODS We consecutively included all 209 patients who received a selective internal radiotherapy intervention between January 2015 and May 2019. A retrospective analysis of their electronic patient records was performed regarding diagnosis of cancer, previous therapies and applied radioactive activity. A multicenter follow-up at least 6 weeks after intervention to assess radiological response and irregular subsequent follow-ups to asses disease progression were conducted. In addition, subgroup analyses were carried out. RESULTS The most frequently treated indications were hepatocellular carcinoma (37%), colorectal cancers (14%), neuroendocrine tumors (9%), and breast cancer (8%). In hepatocellular carcinoma, selective internal radiotherapy was most performed without prior systemic therapy (40%), and for the remaining indications, most often after surgery with systemic therapy in sequence. Local radiological response, defined as either regression or stable disease, was assessed at least 6 weeks after intervention and showed 52% across all indications. Hepatocellular carcinoma (59%) and breast cancer (67%) showed an excellent, colorectal cancers (29%) a particularly poor response rate. Neuroendocrine tumors showed the third longest median post-selective internal radiation therapy (SIRT) survival with 12.4 months and the second longest median progression-free time with 5.2 months. Hepatocellular carcinoma showed even better results with a post-SIRT survival of 15.7 months and a median progression-free time of 5.3 months. Pancreatic neuroendocrine tumors showed significantly worse outcomes than other neuroendocrine tumors, regarding median post-SIRT survival and median progression-free time. No relevant SIRT related differences among sexes were detected. CONCLUSIONS Patients with neuroendocrine tumors, breast cancer in late therapy lines and early-stage hepatocellular carcinoma seem to show better responses to SIRT than other entities. Colorectal cancers were mainly treated with SIRT in a second or third therapy line but with considerably weaker results than other entities

Acute Motor Axonal Neuropathy in a Patient with Metastatic Pancreatic Neuroendocrine Tumor Receiving Chemotherapy with Capecitabine and Temozolomide: A Case Report

We report a case of a 37- year old female patient with metastatic pancreatic neuroendocrine tumor that developed acute motor axonal neuropathy after receiving chemotherapy with capecitabine and temozolomide. She had repeatedly progressed after several surgical resections of her liver metastases, other hepatic directed procedures, several sessions of peptide receptor radionuclide therapy and two systemic treatment lines. When we started a third line therapy with capecitabine (1500 mg absolute twice daily, day 1-14) and temozolomide (360 mg absolute in two divided doses on day 1-5) in a 28 days long cycle, she unexpectedly developed a progressive weakness of the upper and lower limbs and dysphagia. The diagnosis of acute motor axonal neuropathy was confirmed by nerve conduction studies. The patient`s condition improved rapidly after chemotherapy was stopped and plasma exchange (nine sessions) as well as a maintenance therapy with intravenous immunoglobulins was started. She was almost asymptomatic seven months after onset of symptoms. This case describes a previously unreported association between acute motor axonal neuropathy and chemotherapy with capecitabine and temozolomide

The long-term changes in the land use in the Bohemian Socialist Republic (1845-1970)

The changes occurred in the land use on the Liberec and Česka Lipa county areas in years 1845-1905-1948-1961-1970 are examined. The development of the eight major land categories is documented, such as: arables, orchards (fruit orchards, vineyards, hopfields), meadows, pastures, forests, built-up areas, other land, which is taking place on the area of the counties as compared with the rest of the Socialist Republic of Bohemia. The main reasons of these changes are investigated. A method for the calculation of an index of the changes intensity of land use is advanced. This index is employed for and illustrative presentation of the structure of and resources in individual years. The following data are tabaulted: 1. development of land resources in Bohemia in successive periods, 2. comparison of intensity of the changes for the town of Liberec, 3. Intensity of changes for some of the rural districts of the Liberec county (poviat). The cartogram illustrates the intensity of changes that occurred in years 1845-1970 in the part of the county under study: the rural districts considered are given in Table 3. In conclustion the author deals with the regularities discovered. The land use structure alters within larger units: the former homogeneity of the land resources of the fundamental units becomes lost, he concludes. The regularities found will be verified from analogous studies for other areas