2647 research outputs found
Sort by
Optimal design and analysis of a grid-connected hybrid renewable energy system using HOMER Pro: A case study of Tumbatu Island, Zanzibar
Get PDFThis research article was published by Energy Science & Engineering, Volume 12, 2024This study addresses the pressing issue of quality electricity access in remote regions, with a specific focus on Tumbatu Island in Tanzania. Most studies on quality improvement concentrate on low-voltage distribution lines and leave high-voltage (HV) transmission lines behind. It is essential to address quality issues in HV lines due to their critical role in electricity transmission and distribution infrastructure. The objective of the study is to improve the voltage profile on the island's HV transmission line by identifying the optimal hybrid energy system comprising solar PV, wind turbine, and battery technologies. The study begins by presenting the total power demand and consumption on Tumbatu Island, which are important factors in designing an efficient energy system. The findings reveal a power demand of 7173 kW and a consumption of 28540 kWh/day, with an average scaled value of 1507.9 and 6000 kWh/day. To achieve the desired voltage profile improvement, the research incorporates HOMER Pro software for simulating and analyzing various hybrid system configurations. Essential input parameters, such as costs, resources, technology components, and load, are considered in the simulation process. The software generates a ranked list of options based on the system's net present cost (NPC). The simulation results demonstrate that the integration of solar PV, wind turbine, and HV lines provides a substantial improvement in the voltage profile, increasing it from 29.6 to 31.23 kV during peak demand periods. This solution proves to be the most economically viable, with the lowest NPC of $4,003,851 and a relatively short payback period of 3.79 years. In addition, a sensitivity analysis is performed to identify the most influential parameter in the system's performance. Wind speed is found to have the greatest impact, emphasizing its significance in the design and operation of the hybrid energy system. The implementation of this optimal hybrid renewable energy system on Tumbatu Island will not only improve the voltage profile and meet the island's energy needs but also shall contribute to global efforts in reducing pollution and the cost of electricity to the Tumbatu Island population. Moreover, it addresses the current and future demands for clean energy, underlining its importance in achieving sustainable and accessible electricity in sub-Saharan Africa and beyond
Barriers impeding research data sharing on chronic disease prevention among the older adults in low-and middle-income countries: a systematic review
Get PDFThis research article was published by Frontiers in Public Health Volume 12, 2024Introduction: Chronic diseases, including cardiovascular disease, diabetes,
cancer, and chronic respiratory diseases, are a growing public health concern
in low-and middle-income countries (LMICs) among the older population. The
current review aimed to identify the main barriers that impede researchers from
sharing research data on the prevention of chronic diseases in older adults
living in LMICs). The review included both older women and men from these
countries.
Methods: Studies were selected from 11 databases, including Web of Science,
Scopus, PubMed, Taylor and Francis, Biomedical Central, BioOne, CINAHL,
EBSCOHost, ScienceDirect, Wiley Online, and Google Scholar, were then
transferred to CADIMA, an online tool for screening purposes, and a total of
1,305,316 studies were identified through a robust search strategy. CADIMA also
ensured the quality of all studies in this review. The sampling techniques were
performed by selecting and screening studies per this review’s eligibility criteria.
Ultimately, 13 studies were found to meet these criteria. A PRISMA flow chart
was used to map out the number of studies that were identified, included, and
excluded.
Results: Five main barriers were consistently highlighted, including a lack of
necessary resources (9, 69%), dealing with complex and sensitive research
data (2,15%), lack of policies, procedures, guidelines (5,38%), medical big data
processing and integration (2,15%), and inadequate ethical considerations, legal
compliance, and privacy protection (6,46%). Discussion: By shedding light on
these obstacles, researchers can develop strategies to overcome the identified
barriers and address areas requiring further investigation. The registration
details of this review can be found under PROSPERO 2023 CRD42023437385,
underscoring the importance of this review in advancing our collective
understanding of chronic disease prevention among older adults worldwide.
Systematic review registration: PROSPERO, identifier CRD42023437385, available at
Macroeconomic Implications of Oil Price Fluctuations: A Simultaneous Equation Analysis of Russia's Economic Performance and Policy Responses
No full textThis research article was published by Global Academic Journal of Economics and Business 2024This study uses a simultaneous equation model (SEM) to examine the
relationship between oil price fluctuations and Russia's macroeconomic
performance. It uses a comprehensive set of variables, including GDP growth,
investment, export and consumption rates, exchange rates, and oil prices, to
estimate the interactions between these variables. The study reveals significant
findings on the macroeconomic impact of oil price fluctuations on Russia's
economies, including short-term and long-term effects on GDP growth, inflation,
and unemployment rates. It also examines the role of monetary policy in
mitigating the adverse effects of oil price shocks on the economy. The study
highlights Russia's vulnerability to oil price fluctuations, especially due to its
heavy reliance on oil exports. It also examines the effectiveness of policy
responses, such as fiscal measures and exchange rate interventions, in
mitigating the impact of oil price shocks on Russia's macroeconomic stability.
The findings provide valuable insights for policymakers and stakeholders,
aiming to enhance economic resilience and stability in the face of oil market
fluctuations
Natural and low-cost sorbents as part of the solution for biogas upgrading: A review
Get PDFThis research article was published by Adsorption, Volume 30,2024The availability of pollutants in biogas especially carbon dioxide hinders its application in the enginery parts by minimizing its calorific standards. The presence of CO2 contributes to global warming which is a worry globally. Thus, upgrading technologies is needed for safe utilization on small-scale and wide-range. The commercial technologies mostly discussed in the literature are pressure swing adsorption, membrane separation, physical scrubbing, and water scrubbing. These techniques are costly concerning investment, and operation costs, and are energy-intensive, especially on a small scale. Thus, difficult to apply especially in low-income economies, and necessitates the development of natural, low-cost sorbents for biogas upgrading like biomass, eggshell waste, and clay soil. The current review critically evaluates the potentiality of new approaches using low-cost sorbents for biogas upgrading. The review proposed that activating and additional of pore-forming materials in the adsorbents is necessary to significantly enhance their performance
Comparison of Methods to Assess Adherence to Infant and Young Child Feeding Practices and Provision of Low-Aflatoxin Porridge Flours in a Community-Based Intervention Trial
No full textThis research article was published by Nutrients, Volume 16, 2024Background: Levels of adherence to recommended protocols in an intervention trial can affect outcomes and confound the results. To broaden the evidence about the selection and utility of adherence measures in varying contexts, we describe the level of adherence to the Mycotoxin Mitigation Trial (MMT) randomized intervention using caregiver-reported survey questions and compare inferences of adherence between multi-module surveys and interactive 24 h dietary recalls based on our program theory. Methods: The MMT was a two-arm cluster-randomized trial conducted in 52 health facilities (clusters) in central Tanzania. Surveys were conducted with all trial participants at three time points and dietary recalls were conducted in a cohort at 12 mo. Results: The 12 mo survey was conducted with 2112 caregivers and the 18 mo survey was conducted with 2527 caregivers. A cohort of participants (n = 282, 20 clusters) was selected for dietary recalls, balanced by arm. Reported feeding of blended porridge flours, whether MMT-provided or own-sourced, was high at 12 and 18 mo, between 73 and 95%, with only slight differences between the surveys and recalls. Inferences were similar for continuation of breastfeeding, feeding frequency, and dietary diversity. Only the amount of porridge fed the previous day differed statistically by method, with higher amounts reported in the recalls compared to the survey. Conclusions: Detailed analysis of reported behaviors, based on the MMT program theory, supports high adherence to the recommended trial behaviors. Survey data and 24 h dietary recalls were convergent for almost all indicators, strengthening the trial’s conclusions and allowing for either method to be selected for similar research
Unlocking the potential of Tanzania's cashew processing industry: A comparative analysis with Côte d’Ivoire and Mozambique [version 1; peer review: awaiting peer review]
Get PDFThis research article was published by FIOOOResearch,2024Cashew processing is a vital contributor to economic growth in
Tanzania, renowned for its cashew nut production. However, despite
the country’s historical prominence in cashew production, only 5% of
raw cashews undergo local processing, resulting in substantial
economic losses. This paper explores the challenges and
opportunities within Tanzania’s cashew processing industry, focusing
on limited local processing capacity, inefficient tools, raw material
availability, market access, and government support. Comparative
insights from Côte d’Ivoire and Mozambique further enrich our
understanding of the cashew sector. It recommends increasing local
processing capacity, enhancing technical expertise through training,
ensuring a reliable supply of high-quality raw materials, improving
market access via information systems, and strengthening
government support with tailored policy frameworks. Notably, the
paper emphasizes regional collaboration among African cashew-
producing nations as a crucial strategy for collective growth and
knowledge exchange. By drawing upon their experiences, this study
aims to provide guidance for policymakers, industry stakeholders, and
investors to revitalize and sustain Tanzania’s cashew processing
sector
Effect of Natural Pozzolana on Physical and Mechanical Properties of Concrete
Get PDFthis article was published at Hindawi on 13 of February 2024 and Article ID is 3356641.Construction industries are rapidly growing, sacking high amounts of concrete which has a highly dense microstructure with
excellent mechanical properties, more durable, and highly eco-friendly materials. Hence, many of the researchers are interested
in solving this problem with replacing concrete by natural pozzolana (NP) which is a supplementary cementitious material mostly
from volcanic sources having much active silica content that can improve the durability and mechanical properties of concrete.
However, it is not well-known which common optimum replacement range can give the most desirable concrete properties. So, the
present study sought to review the effects of replacing NP from volcanic sources on the durability, physical, mechanical, and
microstructural properties of concrete, also, to identify the most common dose of a positive effect as a replacement in concrete. The
review shows that many of NP used by different literature from different places satisfy ASTM replacement standard in concrete,
especially, based on its chemical compositions. Also, the review observed that employing NP in concrete significantly improves
concrete workability, lengthens setting time, and reduces bulk density, porosity, water absorption, and chloride ion migration by
making denser concrete microstructure. In general, adding 5%–20% of NP in concrete significantly improves compressive strength,
split tensile strength, and flexural strength. Specifically, most of the studies found 15% replacement of NP having volcanic sources
can give optimum strength. Besides these, most of the studies indicated that the improvement of the strength was more visible at
the concrete age of 7–28 days
Industrial -Based GSM Water Leakage Detection, Monitoring and Controlling System in Promoting Sustainability: A Case of Kenyan Industries
Get PDFThis research article was published by Transdisciplinary Journal of Engineering & Science,2024The current system for detecting and monitoring water leaks is manual and costly.
Despite emerging new technological trends, many industries lack automated systems to detect,
monitor, and control water leakage due to the high cost of maintenance and instal
lation. This study
aimed
to develop an automatic, remote, and real
-time detection, monitoring, and control system
for water leaks. The system is made up of two nodes, one at the source and one at the destination
or tap. The two nodes are made up of an ESP microcontroller, which is u
sed to control all the
connected components. The use of the ESP 32 microcontroller was efficient due to its ability to
provide WI
-FI. Aside from the solenoid valve, which was used to turn the water flow on or off in
the event of leaks, the system also incl
udes the FY
-201 water flow sensor, which was used to gauge
the amount of water flowing through the pipe. Water leakage is detected when the volume of water
passing through the two sensors differs in terms of volume, indicating that a water leakage has
just occurred. Thing-
Board, an IoT
-based platform used to monitor and visualize data from
various devices connected, was used for real
-time monitoring, visualization, and control. The
developed system was tested with differ
ent water service providers, and the results showed that
the system responds positively to water leakage parameters with the
capability of monitoring water
leakages in real
-time
, and can contribute to water
sustainability
and
management
effo
rts
for
indutries
.
Cashew apple in Tanzania: status of utilization, challenges, and opportunities for sustainable development
No full textthis article is available in full text at this link https://doi.org/10.12688/f1000research.124596.2Cashew apples, although widely available and rich in nutrients are still underutilized after harvest in Tanzania. Approximately 2,327,000 metric tonnes of cashew apples are lost each year. Their counterpart, the cashew nut is highly appreciated and successfully contributes to the national economy. The huge underutilization of cashew apples is a challenge that requires urgent attention in order to achieve both national and global Sustainable Development Goals (SDGs) by 2030. Improvement of the cashew apple sector could have a positive impact on global SDGs 1, 2, and 3 targets of no poverty, zero hunger, and good health and well-being respectively. At national level, this sector could contribute to the goals of the Tanzania Development Vision (TDV) 2025, namely: high quality livelihood, particularly food self-sufficiency and food security; and a strong and competitive economy, particularly a diversified and semi-industrialized economy with a substantial industrial sector comparable to typical middle-income countries. In addition, the country’s Third Five Year Development Plan III (FYDP III) 2021/22 – 2025/26 has established key strategic interventions, notably those related to competitive industrialization, energy, and food and nutrition security to ultimately achieve the goals of the TDV 2025. To be effective, however, these strategic interventions require continued strong central and local government support and active involvement of stakeholders to ensure program effectiveness yielded towards efficient utilization of widely available natural resources such as cashew apples which has cross-cutting benefits in food, agriculture, health, energy, and economic perspectives. Therefore, the work provides evidence on the utilization status, challenges, and opportunities for sustainable development in Tanzania
Review of Sources of Uncertainty and Techniques Used in Uncertainty Quantification and Sensitivity Analysis to Estimate Greenhouse Gas Emissions from Ruminants
No full textThis research article was published by sustainability 2024Uncertainty quantification and sensitivity analysis are essential for improving the modeling
and estimation of greenhouse gas emissions in livestock farming to evaluate and reduce the impact
of uncertainty in input parameters to model output. The present study is a comprehensive review of
the sources of uncertainty and techniques used in uncertainty analysis, quantification, and sensitivity
analysis. The search process involved rigorous selection criteria and articles retrieved from the Science
Direct, Google Scholar, and Scopus databases and exported to RAYYAN for further screening. This
review found that identifying the sources of uncertainty, implementing quantifying uncertainty, and
analyzing sensitivity are of utmost importance in accurately estimating greenhouse gas emissions.
This study proposes the development of an EcoPrecision framework for enhanced precision livestock
farming, and estimation of emissions, to address the uncertainties in greenhouse gas emissions and
climate change mitigation