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This paper aims to evaluate the effect of optimal use of rooftop photovoltaic (PV) systems on improving the loss of life (LOL) of distribution transformers, reducing power losses as well as the unbalance rate of the 69-bus distribution network.

The problem is studied in three scenarios, considering different objective functions as multi-objective optimization in balanced and unbalanced operations. Meta-heuristic golden ratio optimization method (GROM) is used to determine the optimal size of the rooftop PV in the network.

The simulation results show that in all scenarios, the GROM by optimally installing the rooftop PV is significantly capable to reduce the transformer distribution loss of loss, unbalance rate and power loss as well as reduce the temperature of the oil and transformer winding. Also, the lowest %LOL, power loss and unbalance rate occurred in the second scenario for the balanced network and first scenario, respectively. In addition, the results showed that the unbalance of the network results in increased power losses and LOL of the distribution transformer.

The better capability of GROM is proved compared with the grey wolf optimization algorithm with better objective function and by achieving better values of LOL, unbalance rate and power loss. The results also showed that the %LOL, unbalance and power losses are weakened compared to without considering the PV cost but the achieved results are realistic and cost-effective.

In Nigeria, roselle juice is quite popular among the populace presumably owing to its attractive colour, pleasant flavour and nutritional attributes. In the citrus industry, processing and packing material selection have significant effect on quality of juice product during storage. The effects of packaging materials, and storage temperature on colour and vitamin C retention of sobo juice extracted from local roselle plant were investigated.

Juice was extracted at three different temperatures: 20, 60 and 100°C for varying processing times of 5, 10, 15, 20 and 25 min respectively. Freshly extracted roselle juice was divided into three batches and independently hot‐filled into 500 mL pre‐sterilised glass, film packages and polyethylene terephthalate (PET) bottles allowing for minimum head space, capped, cooled and subsequently stored at 5 ± 1 and 28 ± 1°C respectively for eight weeks.

Optimum pigment extraction was obtained in 20 min with boiling water, while colour stabilisation of the extracted juice was affected with the use of food acidulants. Colour degradation on storage was pronounced in sweetened juice with greater colour loss in product held at ambient temperature. Colour and vitamin C retention with glass and plastic bottles provide higher retention of these quality attributes under cold and ambient storage condition than with the flexible polyethylene film.

Retention of colour and vitamin C was considerably higher in glass and PET bottles than in flexible film package. However, addition of table sugar or increasing storage temperature from 5 to 27°C affected colour stability.

The São Lourenço River (SLR) is used to supply potable waters for the cities of São Lourenço da Serra and Juquitiba, but receives the residues from the water treatment plants (WTPs) and sewage treatment plants (STPs), respectively. The purpose of this paper is to evaluate the impacts of the discharges of Juquitiba’s WTP and STP on the quality of the SLR, by using an integrated approach based on different lines of evidence.

Six sampling sites were established along the river and comprised areas situated upstream and downstream of the discharges. Five sampling surveys were performed between 2004 and 2006 for collecting water and sediment samples for ecotoxicological assays. In two of these campaigns, benthic community structure and geochemistry (metals, nutrients and sediment texture) were also assessed.

Concentrations of P, Fe and Al in waters exceeded the national standards, but sediments were not considered to be contaminated by metals or nutrients. Water and sediments tended to exhibit marginal toxicities, excluding the sediments from JQT007 and JQT008 that were frequently toxic. Combination of geochemistry, toxicity and ecological indices indicated that some sites are not degraded, but in some stations the benthic alteration may be due to non-measured contaminants, especially in JQT007 and JQT008.

As the use of waters from SLR for public supply has increased, these results show that action should be taken in order to reverse the environmental degradation of SRL.

This research combined sediment and water quality assessments in order to provide a more suitable and reliable diagnostic of the environmental quality of the SLR.

The paper seeks to ease the implementation of predictive maintenance policy in industry using the root cause analysis technique, and to compare the reliability and cost effectiveness of root cause based maintenance (RCBM) relative to conventional corrective maintenance (CM).

The system is modularized into its components and maintenance schedules are developed based on each component's individual degradation trends. The effectiveness of RCBM over CM is studied by analyzing system reliability patterns and total maintenance cost functions obtained through empirical cost models, accounting for yield and production loss, maintenance, replacement and catastrophic failure costs. Cost variations for various possible failure distribution parameter values (β, η) under the CM and RCBM policies are also obtained. The proposed methodology is tested in a real aircraft failures case study.

RCBM is generally more effective over CM in achieving timely maintenance at optimal cost (savings up to 65 percent) while keeping high system reliability, for a wide range of (β, η) values. However, CM could still be beneficial for a restricted range of large (β, η).

Industry should consider shifting from CM to adopt the proposed RCBM policy, which is proved to be more efficient in most cases. The implementation is not necessarily complex.

The effectiveness of RCBM over CM in terms of reliability and cost considerations is clearly illustrated. This paper justifies the need to shift from CM to RCBM, which brings us closer to a practical implementation of predictive maintenance. This work also serves as a simple and valuable guide to implementation for maintenance and operational managers in production industries.

The ELHILL 3 system of the National Library of Medicine is one of the world's largest online information retrieval systems, providing access to many different files via MEDLINE, TOXLINE, CATLINE, SDILINE, CHEMLINE, AVLINE, etc. In order to determine whether cost reductions are possible for systems of online bibliographic retrieval, stochastic models were developed that are capable of projecting the operational and cost performance of different configurations handling the same known workload as ELHILL 3. The existing configuration (multiprocessor system consisting of two tightly‐coupled IBM 370/158s) was first modeled, establishing a baseline for performance comparison. A systems approach was followed in building the model. This involved decomposition of the ELHILL 3 system into quantifiable components, analysis of the components, integration of the components into a network model, and performance measurement via discrete event procedures. The model is a network of processing activities, decision points, queues, and services, and the passage of individual user transactions through the retrieval system is simulated. Alternative configurations are modeled (e.g. distributed processing systems) for ELHILL 3, and tested for cost and performance projections.

This paper aims to characterize the pumpkin (Cucurbita sp) seed oil from the varieties Nova Caravela, Mini Paulista, Menina Brasileira (Cucurbita moschata) and Moranga de Mesa (Cucurbita maxima) as to their physicochemical properties, vitamins and fatty acid and triacylglycerols profiles.

The oils were extracted from oilseeds by the Bligh and Dyer (1959) method, and chemical characterization was performed by using standard methods for oils and fats. The vitamin A and E content, fatty acid profile and triacylglycerols profile also were determined.

About the chemical properties, the oils showed values within the range for edible vegetable oils. The oil from variety Nova Caravela stood out for presenting better quality, as it showed lower values of free fatty acids, acidity and peroxides. However, it was found that the Moranga de Mesa oil was the most unsaturated, due to the high refractive and iodine index, and was also reported to have lower oxidative stability. Among the unsaturated fatty acids, ranging from 70 to 78 per cent of the total obtained, linoleic and oleic acids stood out, while among the saturated ones, palmitic and stearic did.

These seeds are rich in high-quality lipids; therefore, their use could help to reduce the amount of waste produced in the industries, and consequently reduce environmental contamination. This study showed that the seeds could be used as a raw material for oil extraction, and also could be used for developing functional foods instead of being discarded.

This study provides valuable information about the quality and fatty acid contents of pumpkin seed oils consumed in Brazil.

Summary Chlorinated rubber primers formulated with active pigments, which are claimed to be non‐toxic and non‐polluting, are investigated; they are designed for the protection of ships (above the waterline), port installation, industrial plants, bridges, etc.

This study investigates the existence of the environmental Kuznets curve (EKC) for deforestation for Ghana over the 1962–2018 the time period.

The study employs a time-varying approach, the bootstrap rolling window Granger causality test to achieve its set objectives.

The results from our study reveals an inverted “N” shape EKC for deforestation, implying that deforestation will initially decrease with increases in economic growth up to a certain income threshold and increases with further increases in economic growth beyond this income threshold up to a higher income threshold and then decrease with further increases in economic beyond the higher income threshold.

The results from the study project show that over time economic growth can serve as a natural panacea to cure and mitigate the ills of deforestation that have plagued Ghana's forests over the years.

The results further highlight the important role of strong institutions in fighting the deforestation menace.

The originality of this study lies in its methodology which allows for feedback from deforestation to the economy. This is in contrast to earlier studies on the EKC for deforestation which allowed causality only from deforestation to the economy.

This paper describes and evaluates the application of a gaming simulation exercise used in a summer school seminar on interdisciplinary research methods. The seminar was held on the Greek island of Skopelos sponsored by the intergovernmental program Man and the Biosphere (MAB) project No. 7 “Ecology and rational use of insular ecosystems” under the auspices of UNESCO's Division of Human Settlements and Socio‐Cultural Environment. The focus of this exercise is the study of tourism's impacts in minor Mediterranean islands and coastal areas. The purpose of the research is to provide decision makers with the basis for sound management of the islands' physical and social resources that would lead to the improvement of the inhabitants’ quality of life. Tourism was identified as one of the most significant sectors in the islands studied.