An online cleaning system to reduce demister fouling in MSF Sidi Krir Desalination Plant, 2 × 5000 m3/day

Analysis of ABWR FW pump performance during power ascending and verification of an operational strategy to jump pump speed across the critical region with RELAP5-3D

As the country uses its reserves of natural gas, it will need to continually replenish them if production is to be maintained. The outlays associated with this continuing search, development and production of new reserves is defined as "replacement costs." Thus, the replacement cost of natural gas is the minimum selling price a firm must receive to recover its costs and to achieve a reasonable return on capital. This paper estimates the range of natural gas replacement costs to the year 2010 and measures the uncertainty associated with these estimates due to the size of the underlying resource base, new unconventional gas extraction technologies, and the rate of domestic gas production.

A new suction detection system for rotary blood pumps used in left ventricular assist devices is presented. The system can correctly classify pump flow patterns, based on a discriminant analysis (DA) model that combines several indices derived from the pump flow signal to make a decision about the pump status. The indices considered in this approach are frequency-, time-, and time-frequency-domain indices. The frequency-domain indices detect changes in the harmonic and subharmonic energy content of the pump flow signal when a suction event is occurring. The time-domain indices detect changes in pump flow pulsatility based on a beat-to-beat analysis of the pump flow and first derivative of pump flow. The time-frequency index can track variations in the standard deviation of the instantaneous frequency of the pump flow signal. These indices are combined in a DA decision system to generate a suction alarm. The proposed system has been tested in simulations and in-vivo experimental tests and produced satisfactory results.

Laser welding is becoming more and more important in automotive industry and quality of the weld is critical for a successful application. In many cases the increase in welding speed provided by laser welding has caused the welding system operator to be unable to keep up with the production rate while inspecting each part. Therefore, either additional inspectors are required, or some form of real time on-line inspection of the weld must be provided. This is especially necessary where the laser weld properties are critical to final product performance. This paper describes architecture of such a system. The proposed system is based on a dynamic model comprised of static and dynamic neural networks.Laser welding is becoming more and more important in automotive industry and quality of the weld is critical for a successful application. In many cases the increase in welding speed provided by laser welding has caused the welding system operator to be unable to keep up with the production rate while inspecting each part. Therefore, either additional inspectors are required, or some form of real time on-line inspection of the weld must be provided. This is especially necessary where the laser weld properties are critical to final product performance. This paper describes architecture of such a system. The proposed system is based on a dynamic model comprised of static and dynamic neural networks.

Increasing power demands and equally growing environmental problems have lead the people to think, develop, and implement new and clean sources of energy to address both the issues. This article presents an optimal system configuration for reliable power generation for unreliable grid‐tied photovoltaic power system for a household in Larkana, Pakistan. The study utilizes HOMER Pro© simulation software along with the required inputs to achieve the set objective. The impact of scheduled and unscheduled power outages, ambient temperature, and PV module tilt angle is considered on the economics of the proposed system. The residential, deferrable, and peak loads are taken as 13.2 kWh/day, 0.52 kWh/day, and 0.6 kW, respectively. Results indicate that the COE of standalone unreliable grid power system with battery storage is 48% more costly compared to unreliable grid/PV system. The proposed system is found to be economically and environmentally more feasible compared to stand alone unreliable grid with battery storage system. © 2018 American Institute of Chemical Engineers Environ Prog, 38:e13031, 2019

This study investigates a marketing and production problem that uses price, warranty length and production rate as simultaneous dynamic decision variables. Furthermore, this study was conducted under a policy of free replacement of defective items; and under conditions where demand was dynamic and dependent on price, warranty and cumulative sales. A continuous profit maximisation model was formulated, which first considers the expected warranty cost per item. Then, it considers the steps for dynamic optimisation, which eventually derive the optimal price, warranty length and production rate. Discretisation was then applied to the profit maximisation model and a digital computer was used to identify the optimal control paths, obtaining a finite solution that is a set of real numbers for practical application. A model-driven Decision Support System is finally established, which provides a graphical user interface for overcoming the complexity of the analytical process. Subsequently, the proposed system was tested and the analytical solution was verified using several demand functions for additive lifetime distributions, thereby demonstrating the system's effectiveness.

As the pump operates and wears out, the gap in the friction pairs increases and the volumetric efficiency decreases, the pump flow gets reduced, which leads to increasing duration of working and auxiliary operations, the operating cycle of the excavator, a decrease in its productivity and excessive fuel consumption. Infrequent pump replacement can lead to a significant increase in fuel consumption and reduced excavator performance. If the pump is replaced prematurely, its service life will not be used to the full extent. In order to develop a method for establishing optimal operating hours that allow minimizing fuel consumption and the cost of replacing a pump, taking into account operating conditions, a mathematical model of the pump operation is proposed, which makes it possible to obtain an expression for determining the differentiated optimal value of operating time between replacements. A calculation method and a software algorithm have been developed in the MatLab Simulink software suite to calculate the rate of decrease in the volumetric efficiency, as well as to establish the influence of volumetric efficiency on the fuel consumption and performance of a hydraulic excavator to be utilized in the model using the example of the HPV375 pump of the Komatsu PC2000-8 excavator, Based on the proposed mathematical model of the main pumps operation, a method has been developed for calculating the differentiated operating time between replacements of the main pumps of a mining hydraulic excavator, taking into account the rate of decrease in volumetric efficiency, replacement costs and damage due to changes in productivity and excessive fuel consumption. The dependence of the rate of changes in the volumetric efficiency of the pump is presented for the excavation, viscosity, contamination and temperature of the working fluid parameters. A coefficient of “reserve of partial engine power transferred to the pump” is proposed, determined by the ratio of the difference between the average maximum and initial partial power to the value of the initial partial power, which allows estimation of the operating time of the main pumps without affecting productivity of the excavator.

The use of pumps as turbines has been gaining more and more attention in recent years. The present work mainly investigates the influence of blade wrap angle on the internal flow and pressure fluctuation characteristics of centrifugal pumps as turbines. Five different wrap angles (35°,45°, 55°, 65°, and 75°) for a forward-curved impeller were numerically analyzed under multiple operating conditions. The accuracy of numerical simulation was validated by experimental results. The results show that maximum efficiency is achieved with a blade wrap angle of 35°, and the highest efficiency flow point gradually decreases as the blade wrap angle increases. It is found by conducting entropy production theory analysis that the high-entropy production rate regions in PATs are concentrated in the volute tongue and impeller blade inlet regions, and that the entropy production rate at the impeller inlet region increases and then decreases as the blade wrap angle decreases. In addition, pressure pulsation was affected not only by dynamic and static interference but also by an irregular vortex around the impeller; its magnitude under Qt is higher than 0.8Qt for blade wrap angles of 55° and 75°. The primary frequency of pressure pulsation within the impeller is the axial frequency fn and its multiples, and the frequency with the largest amplitude is 3fn. The periodicity of vortices is closely related to the periodicity of pressure pulsation. And it is suggested that a PAT with a 35° blade wrap angle is advantageous for improving the stability of a turbine.

Novel configuration of dual-temperature condensation and dual-temperature evaporation high-temperature heat pump system: Carbon footprint, energy consumption, and financial assessment

The influence of blade configuration on cavitation performance of a condensate pump

Optimal smart contract for autonomous greenhouse environment based on IoT blockchain network in agriculture

Investigation of a renewable energy based integrated system with carbon capturing for hydrogen, methane and other useful outputs

Techno-economic analysis of green hydrogen ferries with a floating photovoltaic based marine fueling station

The planning process for roadway construction involves a large amount of information on design, construction methods, quantities, unit costs, production rates, and site conditions. Therefore, it is very important to acquire, manage, and process the necessary information efficiently to produce a rigorous construction plan. The geographic information system (GIS) is a very effective tool for integrating and managing various types of information, including spatial and nonspatial data, required for roadway construction planning. This paper proposes a GIS-based system for improving roadway construction planning with its "interactive space scheduling" and "operation level planning" functions, which are supported by the integration of various data required for planning. The proposed system can assist construction planners in a unique way by integrating design and construction information and creating modularized design elements for space scheduling in real time using its interactive space scheduling function. In addition, operation level planning on earthwork can be conducted via the ability of the system to analyze haul routes in three dimensions and selecting the best equipment combination. It is expected that the proposed system could improve the efficiency of roadway construction planning.Key words: geographic information system (GIS), roadway construction planning, information integration, space scheduling.

Development of a waste tires-based integrated energy system for multiple useful outputs in sustainable communities