scholarly journals A Review of Fouling Mechanisms, Control Strategies and Real-Time Fouling Monitoring Techniques in Forward Osmosis

Water ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 695 ◽  
Author(s):  
Ibrar Ibrar ◽  
Osamah Naji ◽  
Adel Sharif ◽  
Ali Malekizadeh ◽  
Alaa Alhawari ◽  
...  
Keyword(s):  
Real Time ◽  
Membrane Fouling ◽  
Control Strategies ◽  
Forward Osmosis ◽  
Future Research ◽  
Negative Consequences ◽  
Critical Flux ◽  
Monitoring Technologies ◽  
And Control ◽  
The Impact

Forward osmosis has gained tremendous attention in the field of desalination and wastewater treatment. However, membrane fouling is an inevitable issue. Membrane fouling leads to flux decline, can cause operational problems and can result in negative consequences that can damage the membrane. Hereby, we attempt to review the different types of fouling in forward osmosis, cleaning and control strategies for fouling mitigation, and the impact of membrane hydrophilicity, charge and morphology on fouling. The fundamentals of biofouling, organic, colloidal and inorganic fouling are discussed with a focus on recent studies. We also review some of the in-situ real-time online fouling monitoring technologies for real-time fouling monitoring that can be applicable to future research on forward osmosis fouling studies. A brief discussion on critical flux and the coupled effects of fouling and concentration polarization is also provided.

scholarly journals Power Quality in AC Islanded Microgrids: Technical Framework and State of the Art Review

2020 ◽  
Vol 40 (3) ◽  
pp. 29-37
Author(s):  
Vanessa Quintero-Molina ◽  
Ana María Blanco ◽  
Miguel Romero-L ◽  
Jan Meyer ◽  
Andrés Pavas
Keyword(s):  
Power Quality ◽  
Distribution Systems ◽  
Negative Impact ◽  
Control Strategies ◽  
Future Research ◽  
Local Networks ◽  
Islanded Mode ◽  
Power Quality Disturbances ◽  
And Control ◽  
The Impact

In recent years, operation and control strategies in distribution systems have changed due to the increase in the connection of distributed generation sources (DGs). Small local networks with electricity users and DGs are known as microgrids. These microgrids can operate independently (islanded) or in collaboration (interconnected) with the main network or other microgrids. Some advantages of interconnected microgrids include the reduction of losses, an increase in reliability, and decentralized operation under fault conditions. Nevertheless, when a microgrid operates in islanded mode, its electrical characteristics change and, consequently, the severity of power quality disturbances can increase, as well as their negative impact on electronic devices (loads and DG devices). This paper presents a comprehensive literature review of existing studies on power quality disturbances in islanded microgrids and identifies the most relevant needs for future research on this topic. Detailed information is analyzed to compare the differences between disturbance levels in both interconnected and islanded microgrids. In the case of harmonic disturbances, the impact of the different microgrid configurations is also analyzed.

scholarly journals Power Hardware-in-the-Loop-Based Performance Analysis of Different Converter Controllers for Fast Active Power Regulation in Low-Inertia Power Systems

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3274
Author(s):  
Jose Rueda Torres ◽  
Zameer Ahmad ◽  
Nidarshan Veera Kumar ◽  
Elyas Rakhshani ◽  
Ebrahim Adabi ◽  
...  
Keyword(s):  
Performance Evaluation ◽  
Power Systems ◽  
Real Time ◽  
Control Strategies ◽  
Active Power ◽  
Power Electronic ◽  
Hardware In The Loop ◽  
Digital Controllers ◽  
Power Regulation ◽  
The Impact

Future electrical power systems will be dominated by power electronic converters, which are deployed for the integration of renewable power plants, responsive demand, and different types of storage systems. The stability of such systems will strongly depend on the control strategies attached to the converters. In this context, laboratory-scale setups are becoming the key tools for prototyping and evaluating the performance and robustness of different converter technologies and control strategies. The performance evaluation of control strategies for dynamic frequency support using fast active power regulation (FAPR) requires the urgent development of a suitable power hardware-in-the-loop (PHIL) setup. In this paper, the most prominent emerging types of FAPR are selected and studied: droop-based FAPR, droop derivative-based FAPR, and virtual synchronous power (VSP)-based FAPR. A novel setup for PHIL-based performance evaluation of these strategies is proposed. The setup combines the advanced modeling and simulation functions of a real-time digital simulation platform (RTDS), an external programmable unit to implement the studied FAPR control strategies as digital controllers, and actual hardware. The hardware setup consists of a grid emulator to recreate the dynamic response as seen from the interface bus of the grid side converter of a power electronic-interfaced device (e.g., type-IV wind turbines), and a mockup voltage source converter (VSC, i.e., a device under test (DUT)). The DUT is virtually interfaced to one high-voltage bus of the electromagnetic transient (EMT) representation of a variant of the IEEE 9 bus test system, which has been modified to consider an operating condition with 52% of the total supply provided by wind power generation. The selected and programmed FAPR strategies are applied to the DUT, with the ultimate goal of ascertaining its feasibility and effectiveness with respect to the pure software-based EMT representation performed in real time. Particularly, the time-varying response of the active power injection by each FAPR control strategy and the impact on the instantaneous frequency excursions occurring in the frequency containment periods are analyzed. The performed tests show the degree of improvements on both the rate-of-change-of-frequency (RoCoF) and the maximum frequency excursion (e.g., nadir).

scholarly journals Phony peach disease: past and present impact on the peach industry in the southeastern U.S.A

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Kendall A. Johnson ◽  
Clive H. Bock ◽  
Phillip M. Brannen
Keyword(s):  
New Technologies ◽  
Current Knowledge ◽  
Future Research ◽  
Management Options ◽  
Disease Epidemiology ◽  
Pathogen Diversity ◽  
Foundational Research ◽  
Global Threat ◽  
And Control ◽  
The Impact

Abstract Background Phony peach disease (PPD) is caused by the plant pathogenic bacterium Xylella fastidiosa subsp. multiplex (Xfm). Historically, the disease has caused severe yield loss in Georgia and elsewhere in the southeastern United States, with millions of PPD trees being removed from peach orchards over the last century. The disease remains a production constraint, and management options are few. Limited research has been conducted on PPD since the 1980s, but the advent of new technologies offers the opportunity for new, foundational research to form a basis for informed management of PPD in the U.S. Furthermore, considering the global threat of Xylella to many plant species, preventing import of Xfm to other regions, particularly where peach is grown, should be considered an important phytosanitary endeavor. Main topics We review PPD, its history and impact on peach production, and the eradication efforts that were conducted for 42 years. Additionally, we review the current knowledge of the pathogen, Xfm, and how that knowledge relates to our understanding of the peach—Xylella pathosystem, including the epidemiology of the disease and consideration of the vectors. Methods used to detect the pathogen in peach are discussed, and ramifications of detection in relation to management and control of PPD are considered. Control options for PPD are limited. Our current knowledge of the pathogen diversity and disease epidemiology are described, and based on this, some potential areas for future research are also considered. Conclusion There is a lack of recent foundational research on PPD and the associated strain of Xfm. More research is needed to reduce the impact of this pathogen on peach production in the southeastern U.S., and, should it spread internationally, wherever peaches are grown.

The Effect of Concealed Handgun Carry Deregulation in Arizona on Crime in Tucson

2018 ◽  
Vol 30 (8) ◽  
pp. 1186-1203 ◽  
Author(s):  
Michael R. Smith ◽  
Matthew Petrocelli
Keyword(s):  
El Paso ◽  
Future Research ◽  
Multiple Time ◽  
Multiple Time Series ◽  
Training Requirements ◽  
State Adoption ◽  
Concealed Carry ◽  
And Control ◽  
The Impact ◽  
And Training

In 2010, the Arizona legislature effectively deregulated concealed handgun carry in the state by passing Senate Bill (SB) 1108, which eliminated licensing and training requirements for concealed carry. Although researchers have extensively examined the impact of state adoption of concealed carry laws, almost nothing is known about the effects of deregulating concealed carry altogether. This study contributes to the more guns, less crime debate by examining the impact of Arizona’s decision to deregulate concealed carry. Using a multiple time-series research design with an experimental (Tucson) and control city (El Paso), the present study examines the impact of deregulation on handgun-related violent crime and gun larcenies in Arizona’s second largest city—Tucson. We find that the passage of SB 1108 had no impact on handgun-related offenses that could be expected to change following deregulation. The implications of these findings for policy making and future research are discussed.

scholarly journals Towards smart biomanufacturing: a perspective on recent developments in industrial measurement and monitoring technologies for bio-based production processes

2020 ◽  
Vol 47 (11) ◽  
pp. 947-964 ◽  
Author(s):  
Carina L. Gargalo ◽  
Isuru Udugama ◽  
Katrin Pontius ◽  
Pau C. Lopez ◽  
Rasmus F. Nielsen ◽  
...  
Keyword(s):  
Industrial Revolution ◽  
Control Strategies ◽  
Smart Manufacturing ◽  
Monitoring And Control ◽  
Large Sets ◽  
Production Processes ◽  
Recent Developments ◽  
Monitoring Technologies ◽  
And Control ◽  
Industrial Measurement

AbstractThe biomanufacturing industry has now the opportunity to upgrade its production processes to be in harmony with the latest industrial revolution. Technology creates capabilities that enable smart manufacturing while still complying with unfolding regulations. However, many biomanufacturing companies, especially in the biopharma sector, still have a long way to go to fully benefit from smart manufacturing as they first need to transition their current operations to an information-driven future. One of the most significant obstacles towards the implementation of smart biomanufacturing is the collection of large sets of relevant data. Therefore, in this work, we both summarize the advances that have been made to date with regards to the monitoring and control of bioprocesses, and highlight some of the key technologies that have the potential to contribute to gathering big data. Empowering the current biomanufacturing industry to transition to Industry 4.0 operations allows for improved productivity through information-driven automation, not only by developing infrastructure, but also by introducing more advanced monitoring and control strategies.

Assessing the Impact of Temperature Change on the Effectiveness of Insecticide-Treated Nets

2011 ◽  
Vol 3 (3) ◽  
pp. 35-48 ◽  
Author(s):  
Gregory J. Davis
Keyword(s):  
Control Strategies ◽  
Global Climate ◽  
Financial Burden ◽  
Insecticide Treated Nets ◽  
Policy Makers ◽  
Agent Based ◽  
Mosquito Abundance ◽  
Vector Borne ◽  
And Control ◽  
The Impact

Malaria is a vector-borne illness affecting millions of lives annually and imposes a heavy financial burden felt worldwide. Moreover, there is growing concern that global climate change, in particular, rising temperature, will increase this burden. As such, policy makers are in need of tools capable of informing them about the potential strengths and weaknesses of intervention and control strategies. A previously developed agent-based model of the Anopheles gambiae mosquito is extended, one of the primary vectors of malaria, to investigate how changes in temperature influence the dynamics of malaria transmission and the effectiveness of a common malaria intervention: insecticide-treated nets (ITNs). Results from the simulations suggest two important findings. Consistent with previous studies, an increase in mosquito abundance as temperature increases is observed. However, the increase in mosquito abundance reduces the effectiveness of ITNs at a given coverage level. The implications and limitations of these findings are discussed.

scholarly journals Construction worker productivity in hot and humid weather conditions

2019 ◽  
Vol 27 (1) ◽  
pp. 83-108
Author(s):  
Ammar Saeed Mohammed Moohialdin ◽  
Fiona Lamari ◽  
Marc Miska ◽  
Bambang Trigunarsyah
Keyword(s):  
Real Time ◽  
Construction Industry ◽  
Productivity Loss ◽  
Weather Conditions ◽  
Research Field ◽  
Future Research ◽  
Time Data ◽  
Worker Productivity ◽  
Content Type ◽  
The Impact

Purpose The purpose of this paper shows the effect of hot and humid weather conditions (HHWCs) on workers that has resulted in considerable loss in the construction industry, especially during the hottest periods due to decline in worker productivity (WP). Until the last few decades, there is very limited research on construction WP in HHWCs. Nevertheless, these studies have sparked interests on seeking for the most appropriate methods to assess the impact of HHWCs on construction workers. Design/methodology/approach This paper begins by reviewing the current measuring methods on WP in HHWCs, follows by presenting the potential impact of HHWCs on WP. The paper highlights the methodological deficiencies, which consequently provides a platform for scholars and practitioners to direct future research to resolve the significant productivity loss due to global warming. This paper highlights the need to identify the limitations and advantages of the current methods to formulate a framework of new approaches to measure the WP in HHWCs. Findings Results show that the methods used in providing real-time response on the effects of HHWCs on WP in construction at project, task and crew levels are limited. An integration of nonintrusive real-time monitoring system and local weather measurement with real-time data synchronisation and analysis is required to produce suitable information to determine worker health- and safety-related decisions in HHWCs. Originality/value The comprehensive literature review makes an original contribution to WP measurements filed in HHWCs in the construction industry. Results of this review provide researchers and practitioners with an insight into challenges associated with the measurements methods and solving practical site measurements issues. The findings will also enable the researchers and practitioners to bridge the identified research gaps in this research field and enhance the ability to provide accurate measures in HHWCs. The proposed research framework may promote potential improvements in the productivity measurements methods, which support researchers and practitioners in developing new innovative methods in HHWCs with the integration of the most recent monitoring technologies.

scholarly journals Progress in Modeling and Control of Gas Turbine Power Generation Systems: A Survey

Energies ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2358 ◽  
Author(s):  
Omar Mohamed ◽  
Ashraf Khalil
Keyword(s):  
Power Generation ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Power Plants ◽  
Control Strategies ◽  
Research Area ◽  
Future Research ◽  
Modeling And Control ◽  
Comprehensive Survey ◽  
And Control

This paper reviews the modeling techniques and control strategies applied to gas turbine power generation plants. Recent modeling philosophies are discussed and the state-of-the-art feasible strategies for control are shown. Research conducted in the field of modeling, simulation, and control of gas turbine power plants has led to notable advancements in gas turbines’ operation and energy efficiency. Tracking recent achievements and trends that have been made is essential for further development and future research. A comprehensive survey is presented here that covers the outdated attempts toward the up-to-date techniques with emphasis on different issues and turbines’ characteristics. Critical review of the various published methodologies is very useful in showing the importance of this research area in practical and technical terms. The different modeling approaches are classified and each category is individually investigated by reviewing a considerable number of research articles. Then, the main features of each category or approach is reported. The modern multi-variable control strategies that have been published for gas turbines are also reviewed. Moreover, future trends are proposed as recommendations for planned research.

scholarly journals Rapid shifts in the age-specific burden of malaria following successful control interventions in four regions of Uganda

2020 ◽  
Author(s):  
Simon P. Kigozi ◽  
Ruth N. Kigozi ◽  
Adrienne Epstein ◽  
Arthur Mpimbaza ◽  
Asadu Sserwanga ◽  
...  
Keyword(s):  
Control Strategies ◽  
Age Distribution ◽  
Indoor Residual Spraying ◽  
Malaria Prevention ◽  
Older Individuals ◽  
Multinomial Regression ◽  
Transmission Reduction ◽  
Successful Control ◽  
And Control ◽  
The Impact

Abstract Background: Malaria control using long-lasting insecticidal nets (LLINs) and indoor residual spraying of insecticide (IRS) has been associated with reduced transmission throughout Africa. However, the impact of transmission reduction on the age distribution of malaria cases remains unclear. Methods: Over a 10-year period (January, 2009 to July, 2018), outpatient surveillance data from four health facilities in Uganda were used to estimate the impact of control interventions on temporal changes in the age distribution of malaria cases using multinomial regression. Interventions included mass distribution of LLINs at all sites and IRS at two sites. Results: Overall, 896,550 patient visits were included in the study; 211,632 aged <5 years, 171,166 aged 5-15 years, and 513,752 >15 years. Over time, the age distribution of patients not suspected of malaria and those malaria negative either declined or remained the same across all sites. In contrast, the age distribution of suspected and confirmed malaria cases increased across all four sites. In the two LLINs-only sites, the proportion of malaria cases in <5 years decreased from 31% to 16% and 35% to 25%, respectively. In the two sites receiving LLINs plus IRS, these proportions decreased from 58% to 30% and 64% to 47%, respectively. Similarly, in the LLINs-only sites, the proportion of malaria cases >15 years increased from 40% to 61% and 29% to 39%, respectively. In the sites receiving LLINs plus IRS, these proportions increased from 19% to 44% and 18% to 31%, respectively. Discussion: These findings demonstrate a shift in the burden of malaria from younger to older individuals following implementation of successful control interventions, which has important implications for malaria prevention, surveillance, case management and control strategies.

Sign in / Sign up

Export Citation Format

Share Document