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The purpose of this study is to achieve an optimal performance-based design of municipal wastewater collection networks. Sewer deterioration decreases system performance over time and investigations have shown that diameter, slope, structural condition, length, and burial depth are effective factors in hydraulic and structural deterioration. In this research, these factors were used first to develop performance indicators based on velocity, depth of flow, burial depth, pipe slope, and pipe length. Then, using the Non-dominated Sorting Genetic Algorithm II (NSGA-II) and pipe diameter as decision variable, the optimal design of a case study was performed under different combinations of performance indicators. Part of Kerman's wastewater collection network that includes 20 manholes and 20 pipes and one outlet is considered as a case study. The results showed that the pareto points in different combinations of factors in uencing the overall performance are very similar and in all scenarios, the designs tend to increase the slope of the pipe, decrease the diameter, and increase the depth of burial. It was observed that the performance of the network could be improved by about 2% in the case study and almost without imposing additional costs on the basic design. [ABSTRACT FROM AUTHOR]

Stockpiles are of great importance in open pit mine production scheduling and are widely used for different reasons while being placed in different locations. Near face stockpile (NFS) is a new mining concept which combines the IPCC (in-pit crushing and conveying) method with an in-pit near-face (and near crusher) stockpile. The stockpile decouples the whole mining flow into two weakly related subsystems, which are the mining subsystem and processing subsystem. There are many theoretical advantages in comparison to the traditional open-pit mining method, such as higher tolerance on uncertainties without compromising production, higher equipment utilisation, less operating cost, better blending results, etc. The introduction of NFS, however, requires reconsideration of production planning in open pit mines. In this paper, we developed a mixed integer linear programming model to solve long-term production scheduling problem in open pit mines. To quantitatively measure the performance of the NFS mining method, we implemented the model in a real mining case study and compared the results with the traditional open pit mining method with an out-of-pit crusher. The results reveal that implementing the NFS method can improve the net present value by 9.3% and decrease the plant MWT head grade deviation by 20%. [ABSTRACT FROM AUTHOR]

Aim: Optimal treatment of cardiovascular disease is essential to decrease mortality among people with diabetes, but information is limited on how actual treatment relates to guidelines. We analysed changes in therapeutic approaches to anti‐hypertensive and lipid‐lowering medications in people with Type 2 diabetes from 2006 and 2015. Methods: Summary data from clinical services in seven countries outside North America and Western Europe were collected for 39 684 people. Each site summarized individual‐level data from outpatient medical records for 2006 and 2015. Data included: demographic information, blood pressure (BP), total cholesterol levels and percentage of people taking statins, anti‐hypertensive medication (angiotensin‐converting enzyme inhibitors, calcium channel blockers, angiotensin II receptor blockers, thiazide diuretics) and antiplatelet drugs. Results: From 2006 to 2015, mean cholesterol levels decreased in six of eight sites (range: −0.5 to −0.2), whereas the proportion with BP levels > 140/90 mmHg increased in seven of eight sites. Decreases in cholesterol paralleled increases in statin use (range: 3.1 to 47.0 percentage points). Overall, utilization of anti‐hypertensive medication did not change. However, there was an increase in the use of angiotensin II receptor blockers and a decrease in angiotensin‐converting enzyme inhibitors. The percentage of individuals receiving calcium channel blockers and aspirin remained unchanged. Conclusions: Our findings indicate that control of cholesterol levels improved and coincided with increased use of statins. The percentage of people with BP > 140/90 mmHg was higher in 2015 than in 2006. Hypertension treatment shifted from using angiotensin‐converting enzyme inhibitors to angiotensin II receptor blockers. Despite the potentially greater tolerability of angiotensin II receptor blockers, there was no associated improvement in BP levels. What's new?: Mean total cholesterol levels in people with diabetes decreased with a simultaneous increase in statin use.The percentage of people with blood pressure (BP) > 140/90 mmHg increased, which may reflect the change in BP targets from ≤ 130/80 to ≤ 140/90 mmHg that occurred between 2006 and 2015.Anti‐hypertensive treatment approaches shifted towards using more angiotensin II receptor blockers with a simultaneous decline in the use of angiotensin‐converting enzyme inhibitors.Although improved control of high cholesterol in people with diabetes was encouraging, further efforts are required to improve hypertension management in people with diabetes. [ABSTRACT FROM AUTHOR]

This paper presents a new way of interpreting the results of the traditional demand-driven network analysis as an approximation to pressure-driven simulation so as to calculate the reliability of single-source networks. The approach is useful because most network modeling software packages use the demand-driven analysis approach and are incapable of simulating pressure-deficient conditions properly. The formulation draws from recent developments in pressure-driven simulation and can be used to calculate the reliability of an entire water distribution network or that of the individual demand nodes. The method herein is probabilistic in that the random nature of link failures is accounted for. Using a sample network, it is shown that the method has several advantages including simplicity and a very high computational efficiency.

Comments on a paper on the pressure-drive analysis of water distribution networks with reference to less than fully satisfactory performance are presented. The algorithm for network analysis with pressure-dependent nodal outflows seems to be an iterative two-phase formulation. This technique can be applied in appraising the performance of distribution networks whereby the nodal outflows and pressures are less than fully satisfactory.

This study was aimed to assess the eff ect of dietary energy density (kcal/g) on serum levels of adipocytokines of type 2 diabetic women. In this randomized parallel design clinical trial, a total of 60 diabetic women (aged 30-60 years; BMI > 25 kg/m 2 ) were assigned to consume either a low-energy dense (LED) (65 % of energy from carbohydrates and 25 % from fats), normalenergy dense (NED) (60 % from carbohydrates, 30 % from fats), or high-energy dense (HED) diet (55 % from carbohydrates and 35 % from fats) for 8 weeks. The low-energy dense diet was rich in fruits, vegetables, whole grains, and water, while the high-energy dense diet was rich in fats and oils and limited in fruits and vegetables as compared with the normal-dense diet. At baseline and at the end of intervention fasting blood samples were taken to assess metabolic profi le. Women in the LED group consumed signifi cantly more dietary fi ber (p < 0.001), fruits (p < 0.001) and vegetables (p < 0.001) than those in the NED and HED groups. We failed to fi nd a signifi cant eff ect of dietary energy density (kcal/g) on serum adiponectin and visfatin levels. Even the withingroup changes in serum adiponectin and visfatin levels were not signifi cant. Consumption of LED and NED diets resulted in a signifi cant increase in serum chemerin levels (p = 0.04). Comparison of mean changes of serum chemerin levels across 3 groups revealed a signifi cant diff erence (p = 0.04). Our study provides evidence indicating that consumption of HED diet for 8 weeks among diabetic patients prevented the increase in serum chemerin levels compared with LED and NED diets. Furthermore, we found no signifi - cant eff ect of dietary energy density (kcal/g) on serum adiponectin and visfatin concentrations in the current study. the current study. [ABSTRACT FROM AUTHOR]

Analytical solutions are derived for the isothermal pseudoelastic response of a shape memory alloy (SMA) thick-walled cylinder subjected to internal pressure. The Tresca transformation criterion and linear hardening are used. Equations are given for the radial and circumferential stresses, transformation strains and radial displacement at various steps of loading and unloading. A structural pressure–temperature phase diagram is provided for the cylinder, analogous to the stress–temperature phase diagram of SMA materials. Pressurization of an initially 100% austenitic cylinder causes the martensite to initially form at the inner radius. For a relatively thin-walled cylinder the transformation front reaches the outer radius before the transformation has completed at the inner radius, whereas for a thick-walled cylinder the transformation completes at the inner radius while there is still an outer ring of 100% austenite. For a given OD/ID ratio, a critical temperature is derived that stipulates which of these two cases occurs. An analytical result is provided for the pressure that will cause the transformation to complete at the inner radius. During unloading, the reverse transformation can start at either the inner or the outer surface of the cylinder and can propagate outward and then reverse its direction and propagate back to the inner surface. The effect of martensitic transformation on the structural yield strength due to plasticity is also investigated and it is shown that the pressure required to initiate yielding can be substantially decreased or increased depending on the temperature and the state of transformation achieved, even though the yield stress of the material is independent of temperature. Finally, the effectiveness of the Tresca transformation criterion to derive closed-form solutions for this problem is demonstrated by comparing with finite element solutions using the von Mises theory. [ABSTRACT FROM AUTHOR]

The article presents a study which aims to calculate the reliability of pumping stations for Water Distribution Networks (WDNs) with the use of Visual Basic's computer code linked to EPANET2.0. The study concludes that the increase in WDN's demand during a day, pumps' reliability decrease. Moreover, the study mentions that the use of variable speed pumps (VSP) reduce the energy cost of WDN with higher reliability of the pumping stations, in which VSP is recommended for WDNs.

One of the main obstacles in using exact optimisation methods for open pit production scheduling is the size of real mining problems, which forms an intractable optimisation problem. The objective of this paper is to develop, implement, verify and validate a clustering algorithm for block aggregation for the purpose of production scheduling. The algorithm aggregates blocks into selective mining units based on a similarity index which is defined based on rock types, ore grades and distances between blocks. A two-stage clustering approach based on agglomerative hierarchical algorithm and tabu search is developed and tested. The algorithm is validated by a case study on an iron ore life of mine production schedule. The results illustrate that the size and shape of the aggregated blocks have 10–15% effect on the project's net present value and also a significant impact on the practicality of long term production schedules genereated. [ABSTRACT FROM AUTHOR]

In this paper, an optimisation procedure is developed for calibration of the both types of hydraulic simulation models, demand driven and pressure dependent analyses, by using genetic algorithm. Variables of pipe roughness coefficient, nodal demand and pipe diameter are investigated for calibration of the hydraulic models. Four scenarios of minimum, normal, maximum and fire consumption are considered for calibration. In addition, the leakage term is incorporated into the hydraulic equations to be able to evaluate the hydraulic situation more realistically in both demand driven analysis (DDA) and pressure dependent analysis (PDA) based models. The suggested calibration procedure is applied on a test network with different consumption scenarios and variables. It is found that the best results are obtained with fire consumption case and both variables of pipe roughness and nodal demand. Leakage consideration reduces the weaknesses of the low flow scenario and also PDA produces lower error values in comparison with DDA. [ABSTRACT FROM AUTHOR]

This paper describes pressure-driven simulation and highlights the important role that it plays in the management of water distribution systems. Two cases are described for a real water distribution system of about 5,100 nodes serving a population of approximately 44,000. One case involves the simulation of the effects of the failure of a major system component. The other case is concerned with the capacity ofthe distribution system with reference to growing demands over a planning horizon spanning two decades. The examples considered demonstrate the primacy of pressures in water distribution systems and highlight some of the shortcomings of demand-driven methods for analysing water distribution systems. [ABSTRACT FROM AUTHOR]