THE THABINA IRRIGATION SCHEME IN A CONTEXT OF REHABILITATION AND MANAGEMENT TRANSFER: PROSPECTIVE ANALYSIS AND LOCAL EMPOWERMENT

Resource /Energy Economics and Policy,

Development of solar powered water purification systems

Abstract: In this paper, we highlight the effects of contaminated water on humans as well as the crisis of water supply and distribution of potable water in many areas of developing countries. Water is the most important substance on earth. While water is a primary human need, contaminated water can cause and spread diseases. It is, therefore, necessary to ensure that water is purified and decontaminated for daily use at a low-cost. Therefore, the design of solar-powered water purification systems is considered to produce clean water. Solar energy poses no polluting effect; thus, has become a dependable energy source for usage. The design of a solar-powered water purification system is based totally on the thermal method by using the thermal heating system principle. This principle converts sunlight rays into heat. The most vital aspect is the absorption of heat to induce evaporation of water. Research shows that flat plate collectors produce heat at relatively low temperatures (27°C to 60°C) and are commonly used to heat liquids. A solar-powered water purification system consists of a solar collector that absorbs sunlight to ensure vaporisation which is the first stage of purifying and a filter that removes contaminants. Four different concepts have been developed. A detailed description of the components and the operation of the systems constitute the main contribution of this paper

Revival of the magnetar PSR J1622-4950: observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR

New radio (MeerKAT and Parkes) and X-ray (XMM-Newton, Swift, Chandra, and NuSTAR) observations of PSR J1622-4950 indicate that the magnetar, in a quiescent state since at least early 2015, reactivated between 2017 March 19 and April 5. The radio flux density, while variable, is approximately 100x larger than during its dormant state. The X-ray flux one month after reactivation was at least 800x larger than during quiescence, and has been decaying exponentially on a 111+/-19 day timescale. This high-flux state, together with a radio-derived rotational ephemeris, enabled for the first time the detection of X-ray pulsations for this magnetar. At 5%, the 0.3-6 keV pulsed fraction is comparable to the smallest observed for magnetars. The overall pulsar geometry inferred from polarized radio emission appears to be broadly consistent with that determined 6-8 years earlier. However, rotating vector model fits suggest that we are now seeing radio emission from a different location in the magnetosphere than previously. This indicates a novel way in which radio emission from magnetars can differ from that of ordinary pulsars. The torque on the neutron star is varying rapidly and unsteadily, as is common for magnetars following outburst, having changed by a factor of 7 within six months of reactivation.Comment: Published in ApJ (2018 April 5); 13 pages, 4 figure

The 1.28 GHz MeerKAT DEEP2 Image

We present the confusion-limited 1.28 GHz MeerKAT DEEP2 image covering one qb » ¢ 68 FWHM primarybeam area with θ = 7 6 FWHM resolution and s = m - n 0.55 0.01 Jy beam 1 rms noise. Its J2000 center position α = 04h 13m 26 4, δ = −80° 00′ 00″ was selected to minimize artifacts caused by bright sources. We introduce the new 64-element MeerKAT array and describe commissioning observations to measure the primary-beam attenuation pattern, estimate telescope pointing errors, and pinpoint (u, v) coordinate errors caused by offsets in frequency or time. We constructed a 1.4 GHz differential source count by combining a power-law count fit to the DEEP2 confusion P(D) distribution from 0.25 to 10 μJy with counts of individual DEEP2 sources between 10 μJy and 2.5 mJy. Most sources fainter than S ∼ 100 μJy are distant star-forming galaxies (SFGs) obeying the far-IR/ radio correlation, and sources stronger than 0.25 μJy account for ∼93% of the radio background produced by SFGs. For the first time, the DEEP2 source count has reached the depth needed to reveal the majority of the star formation history of the universe. A pure luminosity evolution of the 1.4 GHz local luminosity function consistent with the Madau & Dickinson model for the evolution of SFGs based on UV and infrared data underpredicts our 1.4 GHz source count in the range -5 log Jy 4 [ ( )] S

The MeerKAT Galaxy Cluster Legacy Survey: I. Survey overview and highlights

Please abstract in the article.The South African Radio Astronomy Observatory (SARAO), the National Research Foundation (NRF), the National Radio Astronomy Observatory, US National Science Foundation, the South African Research Chairs Initiative of the DSI/NRF, the SARAO HCD programme, the South African Research Chairs Initiative of the Department of Science and Innovation.http://www.aanda.orghj2022Physic

Revival of the Magnetar PSR J1622-4950: Observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR

New radio (MeerKAT and Parkes) and X-ray (XMM-Newton, Swift, Chandra, and NuSTAR) observations of PSR J1622-4950 indicate that the magnetar, in a quiescent state since at least early 2015, reactivated between 2017 March 19 and April 5. The radio flux density, while variable, is approximately 100 larger than during its dormant state. The X-ray flux one month after reactivation was at least 800 larger than during quiescence, and has been decaying exponentially on a 111 19 day timescale. This high-flux state, together with a radio-derived rotational ephemeris, enabled for the first time the detection of X-ray pulsations for this magnetar. At 5%, the 0.3-6 keV pulsed fraction is comparable to the smallest observed for magnetars. The overall pulsar geometry inferred from polarized radio emission appears to be broadly consistent with that determined 6-8 years earlier. However, rotating vector model fits suggest that we are now seeing radio emission from a different location in the magnetosphere than previously. This indicates a novel way in which radio emission from magnetars can differ from that of ordinary pulsars. The torque on the neutron star is varying rapidly and unsteadily, as is common for magnetars following outburst, having changed by a factor of 7 within six months of reactivation

Development of an automated coconut scraping machine

Abstract: Coconuts are very popular fruits worldwide. They have a variety of uses, health, and nutritional benefits. The uses of coconuts range from cooking and nutrition, skin health, cancer prevention, beauty products, charcoal with a coconut shell. The coconut scraping machines that are commercialized aren’t fully automated and require human hands. Scraping coconut is a laborious and time-consuming process. The manual process requires the operator to both rotate and apply human effort to scrape the meat portion of the coconut. The semi-automated process, on the other hand, requires the operator to hold the coconut half-shell against a rotary blade that rotates usually using an electric motor. Both ways, the operator is presented with dangerous forms of hazards. In this paper, an automated coconut scraping machine has been developed to solve a well know challenge regarding grating coconuts. The design proposed in this study will eliminate virtually all hazards related to coconut scrapers. It is a fully automated machine that takes both risks and effort from the operator. The system incorporates an adjustable blade that allows the movements according to two axes. A clamping mechanism that moves in the third direction allows a three-dimensional movement. The mounting of the coconut half shell in the clamp is set to take no more than fifteen seconds. Upon mounting, at a push of a start button, the scraping of the coconut is to be completely autonomous. Details of the designing and the development of the working model constitute the main contributions of this paper

Framework for Total Productive Maintenance for an SME

Total Productive Maintenance (TPM) is a worldwide maintenance program for plant equipment and machinery. It is a proactive maintenance that optimizes Overall Equipment Effectiveness (OEE) to get rid of the six (6) big losses. The research was inspired by observations made over a six (6) months period at Company X, a Small and Medium Enterprise (SME). Observations made were that the SME produced a lot of defective items, some requiring reworks, the SME had poor maintenance plans, poor relationship between departments, resulting in low morale of workers, frequent breakdowns of machines, as well as low production rate. The main objective of the research was to design a framework that would identify and address the aforementioned problems, resulting in an optimized OEE rate. The research data was obtained through various methodologies, including observation, questionnaire as well as interviews among the company employees - technicians, operators, and maintenance engineers. The data was analysed using Microsoft excel performance dashboards as well as TPM templates. Based on the findings, a framework was designed and developed that sought to address the aforementioned problems at the company. The study improved the OEE of machines and processes through the implementation of TPM approach at Company X

Development and Acceptability of a Tablet-Based App to Support Men to Link to HIV Care: Mixed Methods Approach

BACKGROUND: The poor engagement of men with HIV care is attributed to a number of factors: fear of stigma, masculine representations, concerns related to confidentiality, and the time commitment needed to visit public health clinics. Digital technologies are emerging as an approach to support the engagement of men with care. OBJECTIVE: This study aims to deliver a usable and engaging tablet-based app, called EPIC-HIV 2 (Empowering People through Informed Choices for HIV 2), to support men in making informed decisions about engaging with HIV care in rural KwaZulu Natal, South Africa. METHODS: We employed a mixed methods, iterative, and three-phased design that was guided by self-determination theory (SDT), a person-based approach, and human-computer interaction techniques. We reviewed related literature and conducted secondary analyses of existing data to identify barriers and facilitators to linkage to care and inform content development and design principles and used focus group discussions with members of the community advisory board and general community to evaluate a PowerPoint prototype of the app; used observations and guided questions with a convenience sample of potential users from the intervention community to iteratively test and refine a functioning interactive app; and conducted qualitative interviews and satisfaction surveys with actual users to evaluate acceptability. RESULTS: Phase 1 identified supply- and demand-side barriers to linkage to care. Specifically, clinics were feminized spaces unattractive to men with high social costs of attendance. Men did not feel vulnerable to HIV, preferred traditional medicine, and were afraid of the consequences of being HIV positive. Thus, the app needed to allow men to identify the long-term health benefits to themselves and their families of starting antiretroviral therapy early and remaining on it, and these benefits typically outweigh the social costs of attending and being seen at a clinic. SDT led to content design that emphasized long-term benefits but at the same time supported the need for autonomy, competence, and relatedness and informed decision making. Phase 2 indicated that we needed to use simpler text and more images to help users understand and navigate the app. Phase 3 indicated that the app was acceptable and likely to encourage men to link to care. CONCLUSIONS: We found that iteratively developing the app with potential users using local narratives ensured that EPIC-HIV 2 is usable, engaging, and acceptable. Although the app encouraged men to link to HIV care, it was insufficient as a stand-alone intervention for men in our sample to exercise their full autonomy to link to HIV care without other factors such as it being convenient to initiate treatment, individual experiences of HIV, and support. Combining tailored digital interventions with other interventions to address a range of barriers to HIV care, especially supply-side barriers, should be considered in the future to close the present linkage gap in the HIV treatment cascade