scholarly journals Lead-lag series and staged parallel operational strategies improve the performance and cost-effectiveness of bonechar for control of fluoride in groundwater

2018 ◽  
Vol 8 (4) ◽  
pp. 777-784 ◽  
Author(s):  
J. Kearns ◽  
A. Krupp ◽  
E. Diek ◽  
S. Mitchell ◽  
S. Dossi ◽  
...  
Keyword(s):  
Low Cost ◽  
Operational Strategies ◽  
Decentralized Treatment ◽  
Column Testing ◽  
Long Run ◽  
Resource Poor ◽  
Potential Benefits ◽  
Treatment Technologies ◽  
Operational Modes ◽  
Local Materials

Abstract Affordable, locally managed, decentralized treatment technologies are needed to protect health in resource-poor regions where communities consume groundwater containing elevated levels of fluoride (F). Bonechar is a promising low-cost sorbent for F that can be produced using local materials and simple pyrolysis technology. However, the sorption capacity of bonechar is low relative to the quantities of F that must be removed to meet health criteria (typically several mg/L), especially at pH typical of groundwaters containing high levels of geogenic F. This necessitates large bonechar contactors and/or frequent sorbent replacement, which could be prohibitively costly in materials and labor. One strategy for improving the feasibility of bonechar water treatment is to utilize lead-lag series or staged parallel configurations of two or more contactors. This study used column testing to quantify potential benefits to bonechar use rate, replacement frequency, and long-run average F concentration in treated water of lead-lag series and staged parallel operational modes compared with single contactor mode. Lead-lag series operation exhibited the largest reduction in bonechar use rate (46% reduction over single contactor mode compared with 29% reduction for staged parallel) and lowest long-run average F levels when treating central Mexican groundwater at pH 8.2 containing 8.5 mg/L F.

Low-Cost Technology for Water Pollution Control in Developing Countries

1982 ◽  
Vol 14 (9-11) ◽  
pp. 1337-1352 ◽  
Author(s):  
G G Cillié
Keyword(s):  
Water Pollution ◽  
Developing Countries ◽  
United Nations ◽  
Pollution Control ◽  
Low Cost ◽  
Water Pollution Control ◽  
Local Labour ◽  
International Water ◽  
Design And Methods ◽  
Local Materials

An estimated 80 % of all illnesses in developing countries is in one way or another related to water. In order to alleviate this most serious condition, the united Nations has initiated the “International Water Decade”, for which the estimated costs are $600 000 million, a sum which is far beyond any available means. By application of “low-cost technology” this sum could be reduced to $100 000 million which brings the objective within the reach of possibility. Details are given of the design and methods of construction of units which are best suited to the specific requirements and which would be simple, reliable and economical to operate. These can be constructed largely from local materials and by local labour. The need for appropriate training of both operators and the user population is stressed.

ARSENIC OCCURRENCE IN AFRICAN WATER SYSTEMS AND LOW-COST TREATMENT TECHNOLOGIES

2020 ◽  
Author(s):  
Regina Filemon Irunde ◽  
◽  
Julian Ijumulana ◽  
Julian Ijumulana ◽  
Julian Ijumulana ◽  
...  
Keyword(s):  
Low Cost ◽  
Water Systems ◽  
Cost Treatment ◽  
Treatment Technologies

scholarly journals Removal of Toxic Elements and Microbial Contaminants from Groundwater Using Low-Cost Treatment Options

2021 ◽  
Author(s):  
Dana A. Da’ana ◽  
Nabil Zouari ◽  
Mohammad Y. Ashfaq ◽  
Mohammed Abu-Dieyeh ◽  
Majeda Khraisheh ◽  
...  
Keyword(s):  
Cost Analysis ◽  
Toxic Elements ◽  
Low Cost ◽  
Treatment Technique ◽  
Groundwater Treatment ◽  
Efficient Treatment ◽  
Treatment Techniques ◽  
Cost Treatment ◽  
Treatment Technologies ◽  
Microbial Contaminants

Abstract Purpose of Review This paper reviews various low-cost treatment techniques such as adsorption, permeable reactive barrier, and biological techniques for the simultaneous removal of chemical and microbial contaminants from groundwater and discusses treatment mechanisms of different treatment techniques. This paper also discusses the challenges of groundwater treatment, how to choose the appropriate treatment technique, and cost analysis of groundwater treatment. Recent Findings Various treatment technologies have been used for the treatment of groundwater: physical, chemical, and biological technologies with different success rates. In the literature, various adsorbents have been successfully synthesized from low-cost and environmentally friendly materials. Adsorption is considered an efficient treatment technique for the removal of both toxic elements and pathogens by utilizing different adsorbents. For example, the nanostructures of MgO with a BET surface area of up to 171 m2/g obtained a very high adsorption capacity of 29,131 mg/g for fluoride ions in water, while the incorporation of iron in activated carbon has improved its adsorption capacity to 51.3 mg/g for arsenic. Moreover, certain adsorbents have shown the capability to remove 99% of the rotavirus and adenovirus from groundwater. Summary Groundwater resources are contaminated with toxic metals and pathogens. Therefore, water treatment technologies should be evaluated for their efficiency to remove such contaminants. Determination of the most cost-effective and efficient treatment technique is not an easy task and requires the understanding of various aspects such as the contaminants present in water, the reuse options considered, and cost analysis of the treatment technique.

scholarly journals Soft Spherical Tensegrity Robot Design Using Rod-Centered Actuation and Control

2016 ◽  
Author(s):  
Lee-Huang Chen ◽  
Kyunam Kim ◽  
Ellande Tang ◽  
Kevin Li ◽  
Richard House ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Low Cost ◽  
Space Exploration ◽  
Robot Design ◽  
The Novel ◽  
Flexible Design ◽  
Spherical Robot ◽  
Potential Benefits ◽  
And Performance ◽  
And Control

This paper presents the design, analysis and testing of a fully actuated modular spherical tensegrity robot for co-robotic and space exploration applications. Robots built from tensegrity structures (composed of pure tensile and compression elements) have many potential benefits including high robustness through redundancy, many degrees of freedom in movement and flexible design. However to fully take advantage of these properties a significant fraction of the tensile elements should be active, leading to a potential increase in complexity, messy cable and power routing systems and increased design difficulty. Here we describe an elegant solution to a fully actuated tensegrity robot: The TT-3 (version 3) tensegrity robot, developed at UC Berkeley, in collaboration with NASA Ames, is a lightweight, low cost, modular, and rapidly prototyped spherical tensegrity robot. This robot is based on a ball-shaped six-bar tensegrity structure and features a unique modular rod-centered distributed actuation and control architecture. This paper presents the novel mechanism design, architecture and simulations of TT-3, the first untethered, fully actuated cable-driven six-bar tensegrity spherical robot ever built and tested for mobility. Furthermore, this paper discusses the controls and preliminary testing performed to observe the system’s behavior and performance.

scholarly journals Solid electrolyte interphases for high-energy aqueous aluminum electrochemical cells

2018 ◽  
Vol 4 (11) ◽  
pp. eaau8131 ◽  
Author(s):  
Qing Zhao ◽  
Michael J. Zachman ◽  
Wajdi I. Al Sadat ◽  
Jingxu Zheng ◽  
Lena F. Kourkoutis ◽  
...  
Keyword(s):  
Solid Electrolyte ◽  
Low Cost ◽  
High Energy ◽  
Electrochemical Cells ◽  
Interfacial Chemistry ◽  
Earth Abundant ◽  
Potential Benefits ◽  
High Specific Energy ◽  
Aqueous Aluminum ◽  
Safety Features

Electrochemical cells based on aluminum (Al) are of long-standing interest because Al is earth abundant, low cost, and chemically inert. The trivalent Al3+ ions also offer among the highest volume-specific charge storage capacities (8040 mAh cm−3), approximately four times larger than achievable for Li metal anodes. Rapid and irreversible formation of a high-electrical bandgap passivating Al2O3 oxide film on Al have, to date, frustrated all efforts to create aqueous Al-based electrochemical cells with high reversibility. Here, we investigate the interphases formed on metallic Al in contact with ionic liquid (IL)–eutectic electrolytes and find that artificial solid electrolyte interphases (ASEIs) formed spontaneously on the metal permanently transform its interfacial chemistry. The resultant IL-ASEIs are further shown to enable aqueous Al electrochemical cells with unprecedented reversibility. As an illustration of the potential benefits of these interphases, we create simple Al||MnO2 aqueous cells and report that they provide high specific energy (approximately 500 Wh/kg, based on MnO2 mass in the cathode) and intrinsic safety features required for applications.

scholarly journals Short- and long-term results of low cost trauma training in a low-income resource-poor country

MedEdPublish ◽  
2018 ◽  
Vol 7 (3) ◽  
Author(s):  
Ninos Oussi ◽  
Mitra Sadeghi ◽  
Javeria S. Qureshi ◽  
Charles Mabedi ◽  
Peter Elbe ◽  
...  
Keyword(s):  
Low Income ◽  
Poor Country ◽  
Low Cost ◽  
Long Term Results ◽  
Trauma Training ◽  
Resource Poor Country ◽  
Resource Poor ◽  
Short And Long Term

scholarly journals Low-cost Large Scale Vermicompost Unit

2021 ◽  
Vol 2115 (1) ◽  
pp. 012026
Author(s):  
Sonam Solanki ◽  
Gunendra Mahore
Keyword(s):  
Large Scale ◽  
Low Cost ◽  
Small Scale ◽  
Scale Production ◽  
Key Innovation ◽  
Main Challenge ◽  
Long Run ◽  
Large Scale Production ◽  
Term Maintenance

Abstract In the current process of producing vermicompost on a large-scale, the main challenge is to keep the worms alive. This is achieved by maintaining temperature and moisture in their living medium. It is a difficult task to maintain these parameters throughout the process. Currently, this is achieved by building infrastructure but this method requires a large initial investment and long-run maintenance. Also, these methods are limited to small-scale production. For large-scale production, a unit is developed which utilises natural airflow with water and automation. The main aim of this unit is to provide favourable conditions to worms in large-scale production with very low investment and minimum maintenance in long term. The key innovation of this research is that the technology used in the unit should be practical and easy to adopt by small farmers. For long-term maintenance of the technology lesser number of parts are used.

scholarly journals A Partial Optimization Approach for Privacy Preserving Frequent Itemset Mining

2010 ◽  
Vol 1 (1) ◽  
pp. 19-33
Author(s):  
Shibnath Mukherjee ◽  
Aryya Gangopadhyay ◽  
Zhiyuan Chen
Keyword(s):  
Low Cost ◽  
Synthetic Data ◽  
Frequent Itemset ◽  
Optimization Approach ◽  
Data Generator ◽  
Hidden Cost ◽  
Potential Benefits ◽  
The Difference ◽  
The Given ◽  
Optimal Set

While data mining has been widely acclaimed as a technology that can bring potential benefits to organizations, such efforts may be negatively impacted by the possibility of discovering sensitive patterns, particularly in patient data. In this article the authors present an approach to identify the optimal set of transactions that, if sanitized, would result in hiding sensitive patterns while reducing the accidental hiding of legitimate patterns and the damage done to the database as much as possible. Their methodology allows the user to adjust their preference on the weights assigned to benefits in terms of the number of restrictive patterns hidden, cost in terms of the number of legitimate patterns hidden, and damage to the database in terms of the difference between marginal frequencies of items for the original and sanitized databases. Most approaches in solving the given problem found in literature are all-heuristic based without formal treatment for optimality. While in a few work, ILP has been used previously as a formal optimization approach, the novelty of this method is the extremely low cost-complexity model in contrast to the others. They implement our methodology in C and C++ and ran several experiments with synthetic data generated with the IBM synthetic data generator. The experiments show excellent results when compared to those in the literature.

scholarly journals Air Asia: From Regional to Global

2021 ◽  
Vol 9 (1) ◽  
pp. 1-5
Author(s):  
Dr. Khaliq Ahmad Mohammad
Keyword(s):  
Low Cost ◽  
The Philippines ◽  
Operating Costs ◽  
Economic Downturn ◽  
Long Run ◽  
Low Cost Carrier ◽  
Strategic Options ◽  
Tourism And Hospitality Industry ◽  
Tourism And Hospitality

In February 2009, Tony Fernandez, the founder of AirAsia was not bothered by the company’s mass order of 175 new aircraft for its AirAsia-X long-haul services. He could not resist the concern over the aircraft deferment to Thailand and Indonesia in 2011 because of the relocation of the low-cost carrier terminal in Sepang before AirAsia was forced to move to KLIA2. Such a situation would surely increase its operating costs exponentially. He also knew he was facing an economic downturn and the high competition, particularly for his AirAsia-X business. Major rivals of AirAsia-X in the region were Singapore Tiger Airways, Cebu Pacific Air of the Philippines and a global competitor was EasyJet in Europe had just launched aggressive campaigns and promotions which would affect its long-haul business. He was certain that the company would achieve his dream to spread its wings all over the world. However, he realized that the company’s operating costs and competition with other airliners that joined the club of no-frills airlines based on a national and international level presently had escalated. He knew he had to act now. If you were Tony Fernandez, what would you do in this scenario was a question that needs an answer? This is an issue of strategic choice of divesting or integration as the strategic options are limited in the short as well as long run. The AirAsia case study has the main objective of sharing impact of the covid-19 pandemic devastating impact on the airliners. It is a significant study in terms of impact on economy, tourism and hospitality industry in general and Malaysia in particular.

scholarly journals Thin Vaulted Tile Structure as a Sustainable Slab

2020 ◽  
Vol 9 (9) ◽  
pp. 132-134
Keyword(s):  
Low Cost ◽  
Literature Survey ◽  
Rural Settlements ◽  
The Core ◽  
Roof Structure ◽  
The Earth ◽  
Local Labour ◽  
Concrete Materials ◽  
The Impact ◽  
Local Materials

The concept of sustainability for roof structure becomes most effective because slab consumes the highest amount of cement and steel in the building. This increases carbon footprint, which is a measure of the impact caused by the utilization of natural resources, eventually affecting the earth, and it becomes a subject of higher cost also. The objective of the paper is to find a safe, economical and sustainable roofing structure suitable for suburban and rural settlements. The literature survey carried out deeply and the potential is observed in tile vaulted structures. The core reasons behind adopting a vaulted structure are, it avoids using steel and concrete materials in construction, utilizes local labour, and low-cost local materials for construction. This predominantly becomes the primary factor in deciding the construction of an economical roofing structure for multiple dwelling units in rural and suburban settlements to provide a safe, sustainable and maintenance-free roofing system using tile vaulted structure.

Sign in / Sign up

Export Citation Format

Share Document