Rehabilitation of a water distribution system using sequential multiobjective optimization models

Identification of the optimal rehabilitation plan for a large water distribution system (WDS) with a substantial number of decision variables is a challenging task, especially when no supercomputer facilities are available. This paper presents an initiative methodology for the rehabilitation of WDS based on three sequential stages of multiobjective optimization models for gradually identifying the best-known Pareto front (PF). A two-objective optimization model is used in the first two stages where the objectives are to minimize rehabilitated infrastructure costs and operational costs. The optimization model in the first stage applies to a skeletonized WDS. The PFs obtained in Stage 1 are further improved in Stage 2 using the same two-objective optimization problem but for the full network. The third stage employs a three-objective optimization model by minimizing the cost of additional pressure reducing valves (PRVs) as the third objective. The suggested methodology was demonstrated through use of a real and large WDS from the literature. Results show the efficiency of the suggested methodology to achieve the optimal solutions for a large WDS in a reasonable computational time. Results also suggest the minimum total costs that will be obtained once maximum leakage reduction is achieved due to maximum possible pipeline rehabilitation without increasing the existing tanks

Sequential multi-objective evolutionary algorithm for a real-world water distribution system design

This paper presents a methodology based on a three-stage multi-objective optimization model for solving the problem of Battle of Background Leakage Assessment for Water Networks (BBLAWN) at WDSA2014 conference. At the first stage, the optimal design of pipeline rehabilitation, pump scheduling and tank sizing is formulated and solved on the skeletonized network by a optimizing (1) the costs of pipes, pumps and tank upgrading and (2) the cost of water losses and energy. Three optimal solutions are used for a second optimisation step on the full network (i.e. not skeletonised). The third optimisation step is then performed starting from second stage optimal solutions considering the three objectives of the original proble

Lessons learnt from the use of relationship-based procurement methods in Australia: clients’ perspectives

This paper aims to review the use of various construction procurement systems and present the development of Relationship-Based Procurement (RBP) Methods currently in use within the Australian construction industry. Therefore, this paper provides the historical development of procurement briefly and then focuses on the adoption of Relationship-Based Procurement (RBP) approaches in the Australian construction industry to investigate the future direction of the collaborative project procurement arrangements. Semi-structured interviews with high-level managers in the Australian state government organizations have been conducted to answer the research question. A discussion has been presented about the potential future tendency of the industry in adopting a RBP. The findings suggest that even though relationship based procurement systems offer significant benefits; they are not popular among the public sector decision makers because of inability to demonstrate Value for Money (VfM) propositions for public projects. Other reasons which may cause a move away from using RBPs in the future include the need for managers to fully engage throughout the project, and the lack of collaborative environment within the construction industry in general.

Optimal Rehabilitation Strategy In Water Distribution Systems Considering Reduction In Greenhouse Gas Emissions

Most of water distribution systems (WDS) need rehabilitation due to aging infrastructure leading to decreasing capacity, increasing leakage and consequently low performance of the WDS. However an appropriate strategy including location and time of pipeline rehabilitation in a WDS with respect to a limited budget is the main challenge which has been addressed frequently by researchers and practitioners. On the other hand, selection of appropriate rehabilitation technique and material types is another main issue which has yet to address properly. The latter can affect the environmental impacts of a rehabilitation strategy meeting the challenges of global warming mitigation and consequent climate change. This paper presents a multi-objective optimization model for rehabilitation strategy in WDS addressing the abovementioned criteria mainly focused on greenhouse gas (GHG) emissions either directly from fossil fuel and electricity or indirectly from embodied energy of materials. Thus, the objective functions are to minimise: (1) the total cost of rehabilitation including capital and operational costs; (2) the leakage amount; (3) GHG emissions. The Pareto optimal front containing optimal solutions is determined using Non-dominated Sorting Genetic Algorithm NSGA-II. Decision variables in this optimisation problem are classified into a number of groups as: (1) percentage proportion of each rehabilitation technique each year; (2) material types of new pipeline for rehabilitation each year. Rehabilitation techniques used here includes replacement, rehabilitation and lining, cleaning, pipe duplication. The developed model is demonstrated through its application to a Mahalat WDS located in central part of Iran. The rehabilitation strategy is analysed for a 40 year planning horizon. A number of conventional techniques for selecting pipes for rehabilitation are analysed in this study. The results show that the optimal rehabilitation strategy considering GHG emissions is able to successfully save the total expenses, efficiently decrease the leakage amount from the WDS whilst meeting environmental criteria

Optimal operation of water distribution systems using a graph theory–based configuration of district metered areas

Optimal operation of large water distribution systems (WDS) has always been a tedious task especially when combined with determination of district metered areas (DMAs). This paper presents a novel framework based on graph theory and optimisation models to design DMA configuration and identify optimal operation of large WDS for both dry and rainy seasons. The methodology comprise three main phases of preliminary analysis, DMA configuration and optimal operation. The preliminary analysis assists in identifying key features and potential bottlenecks in the WDS and hence narrow down the large number of decision variables. The second phase employs a graph theory approach to specify DMAs and adjust their configuration based on similarity of total water demands and pressure uniformity in DMAs. Third phase uses several consecutive single-objective and multi-objective optimisation models. The decision variables are pipe rehabilitation, tank upgrade, location of valves and pipes closure, and valve settings for each DMA. The objective functions are to minimise total annual cost of rehabilitation, water age and pressure uniformity. The proposed methodology is demonstrated through its application to large real-world WDS of E-Town. The results show that the proposed methodology can determine a desirable DMA configuration mainly supplied directly by trunk mains

Cause of Death in Emergency Department; a Brief Report

مقدمه: این مطالعه با هدف شناخت اپیدمیولوژیک علل مرگ ومیر در بخش اورژانس بیمارستان امام خمینی شهرستان ارومیه طراحی شده است. روش کار: این مطالعه مقطعی بر روی پرونده کلیه بیماران فوت شده در بخش اورژانس بیمارستان امام خمینی شهرستان ارومیه طی بازه زمانی فروردين تا اسفند سال 1392 انجام شد. اطلاعات دموگرافیک و علل فوت استخراج و در نهایت توسط نرم افزار SPSS 21 مورد تجزیه و تحلیل آماری قرار گرفت. يافته ها: در طی یک سال مطالعه، 396 مورد فوت شده در بخش اورژانس ثبت شد، که در کل پرونده 207 بیمار مورد بررسی قرار گرفت (68 درصد مرد). میانگین سنی افراد فوت شده، 2/5 ±1/63 سال بود (حداقل 3 و حداکثر 94). 159 بیمار در 24 ساعت اول و 48 بیمار در 24 ساعت بعد از مراجعه فوت نموده بودند. شایعترین علت مرگ به ترتیب بیماریهای تنفسی (5/27 درصد)، قلبی (3/21 درصد) و تروما (14 درصد ) براورد گردیدند. نتيجه گيری: بر اساس نتایج مطالعه حاضر به نظر میرسد که بیماری های تنفسی، قلبی-عروقی و تروما شایعترین علت مرگ ومیر در اورژانس باشند، فلذا برنامه ریزی مناسب،آموزش پرسنل و تجهیز کردن مناسب بخش های اورژانس میتواند در کاهش موارد مرگ و میر تاثیر گذار باشد.Introduction: This epidemiologic study was aimed to identify the causes of death in the emergency department of Imam Khomeini hospital in Urmia, Iran. Methods: This cross sectional study was carried out on the profiles of all of the dead patients in the emergency department of Imam Khomeini Hospital in Urmia, Iran who were admitted from April 2013 to March 2014. Demographic data and causes of death were extracted and were then statistically analyzed using SPSS 21. Results: During the studied year, 396 patients were dead in the emergency department, 207 of which were studied (68% male). Mean age for the dead patients was 63.1±5.2 years (minimum 3 and maximum 94). 159 patients were dead in the first 24 hours after admission and 48 in the next 24 hours. The most common causes of death were figured to be respiratory illnesses (27.5%), heart diseases (21.3%) and trauma (14%). Conclusion: Based on the results of this study, it seems that respiratory illnesses, heart diseases and trauma are the most common causes of death in the emergency department. Therefore, proper planning, educating the staff and equipping the department appropriately can be effective in reducing the death rate

Spatial factors related to traffic crashes on pedestrians in all districts of Tehran

Background: A great proportion of deaths due to traffic crashes occur for pedestrians, both in developing and developed countries. Objectives: The aim of the present study was to determine the spatial factors related to the frequency of traffic crashes on pedestrians in districts of Tehran city. Methods: This was a cross-sectional study. All traffic crashes on pedestrians during 2013-2015 were included in this study. The data were extracted from different sources such as traffic police main office, Tehran municipal office, and Iran statistics center. Poisson and negative binomial regression models were used to analyze the role of environment and district on frequency of traffic crashes. Moreover, the likelihood-ratio test has been used for comparison between models, while assessment of goodness-of-fit has been reported using R2, Akaike information criteria, and Bayesian information criteria. Results: Of 12,090 crashes, 11,895 (98.4) had led to injuries, while 195 (1.6) had led to deaths. The frequency of crashes varied substantially in different districts of Tehran. The incidence of injuries did not show any particular pattern, whereas the pattern of incidence of deaths was lower in central districts in comparison to higher incidence in marginal districts (e.g., north, south, west, and east of Tehran). The results of the final model showed a statistically significant association among various variables such as demographics, web of roads, rate of traveling, and land use with the outcome as number of crashes in geographic units. Conclusions: Frequency distribution of traffic crashes leading to injury and/or death is completely different in various districts of Tehran. Demographic as well as spatial characteristics also play an important role in determining this distribution. Regional planning, appropriate traffic management, control measures on spatial risk factors, and educational programs could substantially improve the safety of pedestrians in Tehran

Global burden of chronic respiratory diseases and risk factors, 1990–2019: an update from the Global Burden of Disease Study 2019

Background: Updated data on chronic respiratory diseases (CRDs) are vital in their prevention, control, and treatment in the path to achieving the third UN Sustainable Development Goals (SDGs), a one-third reduction in premature mortality from non-communicable diseases by 2030. We provided global, regional, and national estimates of the burden of CRDs and their attributable risks from 1990 to 2019. Methods: Using data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, we estimated mortality, years lived with disability, years of life lost, disability-adjusted life years (DALYs), prevalence, and incidence of CRDs, i.e. chronic obstructive pulmonary disease (COPD), asthma, pneumoconiosis, interstitial lung disease and pulmonary sarcoidosis, and other CRDs, from 1990 to 2019 by sex, age, region, and Socio-demographic Index (SDI) in 204 countries and territories. Deaths and DALYs from CRDs attributable to each risk factor were estimated according to relative risks, risk exposure, and the theoretical minimum risk exposure level input. Findings: In 2019, CRDs were the third leading cause of death responsible for 4.0 million deaths (95% uncertainty interval 3.6–4.3) with a prevalence of 454.6 million cases (417.4–499.1) globally. While the total deaths and prevalence of CRDs have increased by 28.5% and 39.8%, the age-standardised rates have dropped by 41.7% and 16.9% from 1990 to 2019, respectively. COPD, with 212.3 million (200.4–225.1) prevalent cases, was the primary cause of deaths from CRDs, accounting for 3.3 million (2.9–3.6) deaths. With 262.4 million (224.1–309.5) prevalent cases, asthma had the highest prevalence among CRDs. The age-standardised rates of all burden measures of COPD, asthma, and pneumoconiosis have reduced globally from 1990 to 2019. Nevertheless, the age-standardised rates of incidence and prevalence of interstitial lung disease and pulmonary sarcoidosis have increased throughout this period. Low- and low-middle SDI countries had the highest age-standardised death and DALYs rates while the high SDI quintile had the highest prevalence rate of CRDs. The highest deaths and DALYs from CRDs were attributed to smoking globally, followed by air pollution and occupational risks. Non-optimal temperature and high body-mass index were additional risk factors for COPD and asthma, respectively. Interpretation: Albeit the age-standardised prevalence, death, and DALYs rates of CRDs have decreased, they still cause a substantial burden and deaths worldwide. The high death and DALYs rates in low and low-middle SDI countries highlights the urgent need for improved preventive, diagnostic, and therapeutic measures. Global strategies for tobacco control, enhancing air quality, reducing occupational hazards, and fostering clean cooking fuels are crucial steps in reducing the burden of CRDs, especially in low- and lower-middle income countries

The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe