Artificial Pools Research Articles

Heat Attainment and Retention in Surfers with and without a Land-Based Warm-Up and Accompanying Passive Heat Retention.

Surfing is a growing, high-participation recreational and competitive activity. It is relatively unique, being performed on, in, and through water with a range of temperatures. In other sports, warm-up and heat retention have proved useful at augmenting performance and ameliorating injury risk. Little work has been carried out examining this in surfing. The purpose of this work was to measure thermal profiles in surfers with and without warm-up and passive heat retention, and secondarily to assess any potential influence on free surfing. A repeated measures pre- and post- design was adopted whereby participants surfed in an artificial wave pool following an active warm-up combined with passive heat retention (experimental condition) and after no warm-up (control). Core body temperature was measured both occasions. Our results showed increases in core body temperature were greater for the experimental condition versus control (p = 0.006), and a time effect exists (p < 0.001)-in particular, a warm-up effect in the water itself was shown in both groups, possibly due to further activity (e.g., paddling) and wetsuit properties. Finally, performance trended to being superior following warm-up. We conclude that body warmth in surfers may be facilitated by an active warm-up and passive heat retention. In free surfing, this is associated with a trend towards better performance; it may also reduce injury risk.

Characterization of cyanobacterial mats from an artificial hot spring in Uniejów (Poland) and the potential use of their biomass

Artificial geothermal water systems are an efficient and low-cost alternative to natural ecosystems for phototrophic microorganism biomass production on an industrial scale. Our study focused on the investigation of mat-forming cyanobacteria produced in an artificial pool with a geothermal water source from a hot spring in Uniejów, Poland. The microorganisms inhabiting this ecosystem tolerate the high salinity (approximately 50 ‰) and temperature (45-55.2 °C) of the water. The structure, composition, and growth rates of the cyanobacterial mats were investigated under natural and laboratory conditions. We tested whether cyanobacteria harvested from this habitat represent a safe source of vital biomolecules for industrial applications. We found that the layered mats consisted of simple filamentous cyanobacteria, mainly of the genera Leptolyngbya, Thermoleptolyngbya, and Anagnostidinema. In the isolated cyanobacteria, we did not detect commonly studied cyanotoxins (i.e., ATX-a, BMAA, CYN, MC, and SXT) that could pose a direct risk to human health and lead to indirect risks through the contamination of bioproducts. The extracts and filtrates of the strains did not reduce the survival of Daphnia. In addition, we found that temperatures of 40-50 °C and pH values of 7.2-7.7 were optimal for mat formation and the growth of the dominant cyanobacteria. In the case of the Desertifilum dzianense strain, the highest biomass yield was noted at 26 °C. In summary, our study indicates that mat-forming cyanobacteria inhabiting ecosystems powered by geothermal waters from the Uniejów hot spring have strong potential as bioresources for different industrial applications.

Underwater multi-sensor fusion localization with visual-inertial-depth using hybrid residuals and efficient loop closing

Unmanned underwater vehicles (UUVs) need robust localization systems to complete their missions safely. To address the degradation of the localization accuracy of UUVs using visual-based simultaneous localization and mapping (SLAM) in underwater environments. A full SLAM system that fuses visual-inertial-depth measurements using hybrid residuals and efficient loop closing is proposed. Specifically, a novel visual hybrid residual is presented with an adaptive dynamic weighting factor. Reprojection and photometric double constraints are constructed simultaneously using the selected robust features. These constraints are then optimized jointly with the IMU measurements and the relative depth measurements to obtain a more accurate pose. Furthermore, a new three-step image-to-sequence strategy and a convolutional auto-encoder (CAE)-based global image representation are adopted to select candidate frames in order to improve the recall of underwater visual loop closure detection. Quantitative and qualitative analyses of real-world artificial pool and ocean experiments demonstrate the accuracy and effectiveness of the proposed system.

Microbial Eukaryotes in Natural and Artificial Salt Marsh Pools

Microscopic eukaryotes are important components of coastal wetland ecosystems. The goal of this study was to investigate the diversity of microeukaryotes in the tidal pools of a New Jersey salt marsh and to compare the assemblages of natural and artificial pools excavated for controlling mosquito populations. We evaluated microeukaryotic assemblages using the amplicon sequencing of 18S and rbcL DNA markers and the microscopic identification of diatoms in water and sediment samples. 18S unique amplicon sequence variants (ASV) representing ciliates, dinoflagellates, diatoms, and cercozoans were the most diverse, while the reads of dinoflagellates, diatoms, ciliates, and nematodes were the most abundant. The dominant ASVs were attributed to organisms that are characteristic of coastal plankton and sediments or those known for their resistance to salinity, desiccation, hypoxia, and UV stress. The sediment assemblages were more diverse compared to those from the water column and contained a larger portion of ASVs that were not assigned to any low-rank taxa, reflecting the current gaps in understanding the diversity of microeukaryotes. Most taxonomic groups were significantly different in their abundance and composition between natural and artificial pools. Dinoflagellates, haptophytes, chrysophytes, pelagophytes, and raphidophytes—the groups that include a large proportion of mixotrophic taxa and species known for forming harmful algal blooms—were more abundant in the artificial than in the natural pools. Fungi, labyrinthulomycetes, and peronosporomycetes were also more abundant in artificial pools, which may be related to organic matter enrichment. Diatoms and foraminifera showed an opposite trend of higher abundance in natural pools.

The effects of a land-based warm-up and accompanying passive heat retention on core body temperature, hormones, and subsequent performance in elite surfers.

Surfing is a high participation sport, yet little sport science research exists regarding competitive performance in surfing. Given surfing's inclusion as an Olympic sport from the 2020 Tokyo Olympics onwards, an examination of performance would seem useful. In numerous land-based sports, and in swimming, the importance of a warm-up and muscle heat is well documented. However, surfing is a unique sport in that it is undertaken both above and below water. Therefore, the aim of this study was to explore the effectiveness of a warm-up in terms of readiness to perform in surfing. We discuss this in the context of thermal regulation, hormone profile change, and the subsequent expression of "power" on waves-a key criteria that surfers are scored for. Nineteen advanced level surfers (i.e., competitive at just below national level in Australia; n = 15 males and n = 4 females) with mean (±SD) age, height, and weight of 24.5 ± 11.6 years, 174.7 ± 9.1 cm, and 67.7 ± 10.2 kg, respectively, were recruited. We adopted a repeated measures pre- and post-design whereby participants engaged in several simulated surfing competitions in an artificial wave pool; once after an active warm-up combined with a passive heat retention strategy (i.e., wrapping themselves in survival blankets-treatment), and once after no warm-up (control). Saliva samples were collected pre- and post-active warm-up, or at equivalent times under control conditions, for the measurement of testosterone and cortisol. Increases in these hormones have previously been associated with an enhanced readiness to compete. Our results demonstrate a clear thermoregulatory benefit from the treatment, with the participants' core body temperatures typically higher from the end of the warm-up to the end of the surf session following treatment (p ≤ 0.03), and a magnitude of increase in core body temperature once in the water that is greater following treatment (p = 0.01). A small magnitude upward change in testosterone (p = 0.01) and cortisol (p ≤ 0.001) following warm-up was also observed. Finally, warm-up was associated with an improved wave performance compared with the control, with a 20% increase in the performance score typically observed (p ≤ 0.01). We argue that the improved thermal profile may have influenced power and, as such, surfing performance was enhanced.

Spatio-temporal usage of water sources by Black-cheeked Lovebirds Agapornis nigrigenis: implications for conservation planning

Summary The Black-cheeked Lovebird Agapornis nigrigenis has a highly restricted range in dry south-western Zambia, where its distribution is clumped and localised in association with mopane Colophospermum mopane woodland and permanent water pools. Fieldwork and monitoring over 30 months between December 2018 and October 2021 established that the lovebirds’ usage of pools for drinking was higher towards the centre of the bird’s distribution and influenced by the pools’ proximity to mopane woodlands, surrounding tree cover, and level of human activity. Of the four pool types available for use by lovebirds (i.e. mopane, grassland, river, and artificial), mopane and grassland pools were disproportionally susceptible to drying out in the dry season, hence showed greater variation in numbers of visiting birds compared with the other two types. Lovebirds showed a preference for pools with a perimeter of &lt;50 m and tended to avoid those with a perimeter &gt;100 m, consistent with a positive association between pool size and human activity. Convergence between humans and lovebirds in dependence on water resources and mopane woodland points to the need to find ways to overcome potential conflicts. Such ways include creating small, shallow-sided, undisturbed pools in or near mopane woodland, extending water retention in existing mopane pools, and enhancing the capacity of artificial pools to meet the needs of the lovebirds.

From shady ditches to artificial pools – Does mire restoration benefit aquatic invertebrates?

To combat the loss of wetlands and the services they provide, many are now being restored. Rewetting, usually by ditch blocking, is a common approach to restore drained wetlands, where it can create a supply of permanent artificial pools. We studied how aquatic macroinvertebrate abundance, species richness and communities respond to ditch blocking, and how the new lentic waterbodies contribute to the habitat value of these ‘restored’ ecosystems. The study system was a large before-after-control-impact (BACI) experiment along forested mixotrophic bog edges, where we sampled macroinvertebrates prior to and after the restoration that had created a total of 308 individual pools along former ditch channels. The mean abundance and taxon richness increased similarly in drain-blocked and control ditches between 2015 and 2021 but blocked and control ditches started to host distinct communities. Most pronounced changes were the decrease in the numbers of bivalves and plecopterans and the appearance of vagile species, such as odonatans, hemipterans and certain beetles and flies to blocked ditches, including several characteristic species. Overall, the restoration provided new habitats for aquatic macroinvertebrates, but the convergence of these communities toward natural transitional mire communities remains to be studied.

Rainwater Quality Analysis for Its Potential Recovery: A Case Study on Its Usage for Swimming Pools in Poland

This paper describes the possibility of using rainwater for filling artificial swimming pools in Poland. The overall purpose of this study is to understand whether the quality of rainwater collected from roofs would be suitable for use in the swimming pools without any additional treatment. The rainwater samples were collected from five areas in the Silesian region and analysed for a number of physico-chemical parameters. The results show that the content of nitrates met Polish standards, whereas the standards set for pH and turbidity would only be met after the water had undergone the treatment process which takes place in every swimming pool installation. The paper further compares rainwater data from this study with the corresponding data for drinking water and groundwater. It shows that the content of ammonia, some metals (Ni, Cr and Mn) and a semimetal are in line with the parameters used for drinking water and are a lot lower compared to those set for groundwater. However, the results indicated some possible consequences which might be harmful for swimming pool users. These include the adverse effects of zinc and other organic micropollutants which are classified as contaminants of emerging concern (CECs). These may form dangerous byproducts in the presence of the chlorine, the use of which is required by the standards to be applied for swimming pool disinfection purposes.

Providing water sources to insectivorous bats for conservation biological control in arid date plantations

Balance between the high demand for agricultural production and the negative environmental impact of intensive agriculture requires the development of sustainable agricultural approaches. One such approach is conservation biological control (CBC), which aims at enhancing pest suppression by using natural enemies, such as predators and parasites. Insectivorous bats are considered as potential natural enemies for CBC of insect agricultural pests. Bats drink from open water sources and forage above them, hence we hypothesized that supplementation of artificial water pools adjacent to desert date plantations might promote the activity and species richness of insectivorous bats in this habitat, thereby contributing to pest suppression. We predicted that bats will be more attracted to the pools during summer, when other water sources are scarce, than during spring. In addition, we explored the effect of water supplements on the desert bat community structure. Eight pools were installed in a date plantation in the hyper-arid Arava valley, Israel. Bats were acoustically monitored during three experimental stages: 1) before filling the pools with water; 2) while the pools held water and 3) after emptying them. The lesser date moth (Batrachedra amydraula), a major date pest, was monitored using pheromone traps in parallel with the experimental stages. We found that the pools increased bat activity in summer, but not in spring, while species richness was not affected in either season. The local bat community structure was significantly altered while the pools held water, but not due to increased activity of synanthropic Mediterranean species at the expense of local desert species. The number of individuals of the lesser date moth near the pools decreased with the increase in bat activity. Our results support the idea that seasonal water supplementation enhances bat activity in arid farmlands with potential contribution to pest control and the actual contribution to pest suppression should be further quantified. We suggest that the integration of small artificial pools to promote agricultural pest predation by bats may help reduce crop loss and potentially contribute to the conservation of desert bat communities by adding water sources.

Improved Prediction of Aquatic Beetle Diversity in a Stagnant Pool by a One-Dimensional Convolutional Neural Network Using Variational Autoencoder Generative Adversarial Network-Generated Data

Building a reasonable model for predicting biodiversity using limited data is challenging. Expanding limited experimental data using a variational autoencoder generative adversarial network (VAEGAN) to improve biodiversity predictions for a region is a new strategy. Aquatic beetle diversity in a large &gt;30-year-old artificial pool that had not had human interference in Nanshe Village (Dapeng Peninsula, Shenzhen City, Guangdong Province, China) was investigated. Eight ecological factors were considered. These were water temperature, salinity, pH, water depth, proportional area of aquatic plants, proportional area of submerged plants, water area, and water level. Field sampling was performed for 1 or 2 days in the middle or late part of each month for a year. A type D net was swept 10 times in the same direction in each ~1 m × ~1 m sample square, generating 132 datasets (experimental data). In total, 39 aquatic beetle species were collected, 19 of which were assigned to Hydrophilidae, 16 to Dytiscidae, 3 to Noteridae, and 1 to Gyrinidae. A one-dimensional convolutional neural network (1-D CNN) was used to assess and predict the grade of the number of individuals and the number of aquatic beetle species. The Bayesian-optimized 1-D CNN established using 112 experimental datasets as the training set and the other 20 datasets as validation and testing sets gave a 74.0% prediction accuracy for the grade of the number of individuals and a 70.0% prediction accuracy for the number of species. The impact of insufficient sample data on the model was assessed using a VAEGAN to expand the training set from 112 to 512 samples, and then the Bayesian-optimized 1-D CNN-based VAEGAN prediction model was re-established. This improved prediction accuracy for the grade of the number of individuals to 86.0% and for the number of species to 85.0%. The grade of the number of individuals’ prediction accuracy was 88.0% and the number of species’ prediction accuracy was 85.0% when the random effects of only obtaining a single individual of a species were excluded. The results indicated that the accuracy of the 1-D CNN in predicting the aquatic beetle species number and abundance from relevant environmental factors can be improved using a VAEGAN to expand the experimental data.

Comparison of Velocity and Reynolds Stress Distributions in a Straight Rectangular Channel with Submerged and Emergent Vegetation

Vegetation in rivers and streams plays an important role in preventing erosion and improving bank stability. Comparison between emergent vegetation (bank vegetation) and submerged vegetation, in terms of velocity and Reynolds stress distributions, for the same aspect ratio and flow discharge, has received limited attention in the literature. This study investigates the velocity and Reynolds stress, as well as the log law for submerged and emergent vegetation in a laboratory flume and compares the results for a different set up with different sediment size and aspect ratio but the same discharge. The results indicate that the influence of submerged vegetation on the secondary currents generation is less than emergent vegetation. In addition, the log law application is valid for both submerged and emergent vegetation cases, however, it is valid up to y/h = 0.75 for emergent vegetation (in which the vegetation cover in banks is partly out of the water) but up to y/h = 0.25 for vegetation bank. For both submerged and emergent vegetation, Reynolds stress distribution presents a convex form but with a different turning point. Comparison of the results with those in an artificial pool over submerged vegetation and low aspect ratio (&lt;5) keeps almost the same form for velocity and Reynolds stress distributions but decreases the turning point in Reynolds stress distribution. For the submerged vegetation cover, the location of zero shear stress superposes that of maximum velocity, but for the emergent vegetation approaching the bank vegetation and shifting the maximum velocity towards the bed, the location of zero shear stress approaches the bed.

Turbulence Kinetic Energy and High-Order Moments of Velocity Fluctuations of Flows in the Presence of Submerged Vegetation in Pools

The flow in arid and semi-arid regions changes significantly during seasons, letting many vegetation patches develop in different parts of rivers. In the presence of aquatic plants in streams, different flow structures have resulted. When the water level increases in these rivers, the presence of vegetation patches influences the turbulent flow structures, which may considerably change the estimation of key hydraulic parameters. The results of earlier investigations indicated that a wide range of submerged and non-submerged vegetation influences the hydrodynamic features of flows in rivers and streams. In the present investigation, two pools with various slopes of entry and exit sections were used to conduct eight independent experiment runs. In addition, a vegetation patch over the entire pool section has been set up to investigate the effects of the vegetation patch on flow structures in pools. The effect of two slopes of 5 and 10 degrees for both entrance and exit of the pools on flow structure has been investigated. Considering two aspect ratios of 2.0 and 2.7, the distributions of flow velocity, Reynolds normal and shear stresses, turbulence intensities, turbulent kinetic energy (TKE), quadrant analysis, and spectral analysis have been studied at the trailing edge of the vegetation patch along an artificial pool. Results show that, for large entrance and exit slopes (10 degrees), the TKE distribution profiles have no specific form. However, the TKE values have a convex-shaped distribution pattern with the maximum TKE value near the bed when the slopes of the entrance and exit sections of the pool are small (5 degrees). Results showed that both ejections and sweeps govern the turbulence structures and coherent motions at the trailing edge of the vegetation patch along the pool. The geometry, entrance, and exit slopes of the pool have no effect on the validation of power spectral function compared to the presence of a vegetation patch in a flatbed.

Research on Biomass Waste Utilization Based on Pollution Reduction and Carbon Sequestration

Biomass waste in agricultural and forestry production has low value, large volume, disordered texture, high water content, and high recycling costs, disturbing its biomass waste treatment. In terms of mainstream treatment methods, incineration directly releases carbon dioxide, dust, and other pollutants, while landfills produce carbon dioxide and methane with stronger greenhouse effects. In response to this problem—taking pollution reduction, carbon sequestration, and the resource utilization of biomass waste as the purpose—a mode of in-situ, harmlessness, homogenization, reduction, automation, inorganic transformation, resource utilization, and carbon sequestration is proposed, which reduces recycling costs and improves economic efficiency and operability with carbonization as the key technique. The carbonization mechanism of biomass waste was first investigated using TGA analysis to obtain the key technical parameters of in-situ carbonization, and then biomass carbonization was divided into two stages: in-situ carbonization and factory carbonization. Thus, a process is constructed for in-situ crushing, carbonization, screening, and recycling, which promotes the recovery efficiency of biomass waste, including domestic waste. Moreover, on the basis of massive experiments, a carbon-based material was invented where, through wide applications in architecture, huge carbon can be stored in building materials; thus, a novel method of biomass waste resource utilization, carbon sequestration, and artificial carbon pool construction was established. Among them, with the convenient collection of biomass waste as the premise, the economic and reasonable carbonization process is a pivotal step to guarantee the wide application of carbon-based materials, and pollution reduction and carbon sequestration are the final purposes. This novel mode is conducive to saving resources and realizing carbon peaking and carbon neutrality goals with significant economic, ecological, and social benefits. The novelty lies in five aspects. Firstly, differing from current research on pollution reduction, carbon reduction, and carbon balance, further research on carbon sequestration was proposed. Secondly, the feasibility of reducing re-emission through carbon transfer was demonstrated. Thirdly, in-situ carbonization to recycle biomass waste was constructed. Fourthly, through carbonization, the inorganic transformation of biomass waste avoided carbon re-emission, especially methane emissions. Last but not the least, carbonization products achieved carbon sequestration and constructed an artificial carbon pool.

Characteristics of Shallow Flows in a Vegetated Pool—An Experimental Study

Pools are often observed in gravel-bed rivers, together with the presence of vegetation patches. In the present study, a conceptual model of a gradual varied flow with both convective deceleration and acceleration flow sections has been constructed in a flume to study turbulent flow structures. Vegetation patches with extended canopies were planted in the pool sections in order to increase the thickness of the boundary layer inside the inner zone. The effects of different flows (namely decelerating, uniform and accelerating flows) along an artificial pool on flow velocity, shear stress and bursting events have been investigated. In addition, due to the occurrence of secondary currents in shallow streams, the characteristics of turbulent shallow flow have been investigated along two axes that are parallel to the sidewall of the flume. The results showed that the application of the log law should be used with care to estimate shear velocity along a pool with a vegetated bed. The presence of a vegetation patch causes an increase in Reynolds shear stress, especially along the entrance section of the pool where the flow decelerates. The results of the quadrant analysis reveal that the sweep and ejection events have the most dominant influence over the vegetation patch in the pool; however, the contributions of outward and inward events increase near the bed, especially in the entrance section of the pool where the flow is decelerating. The distribution of stream-wise RMS of turbulence intensity along the pool generally presents a convex shape.

ENERGY PERFORMANCE ANALYSIS OF R32 AND R134A REFRIGERANT FOR SPRING POOL WATER HEATER

For a country with a tropical climate, such as Indonesia, heat pump technologies are usually necessary in high-altitude regions, where the temperatures tend to be cooler, such as a pool heater for an artificial hot spring swimming pool. A vapor compression heat pump’s optimal performance relies on its working fluid’s characteristics. This paper aimed to assess the performance and compare the time required to heat a hot spring pool using heat pumps with two different refrigerants: R32 and R134a. A thermodynamic modeling approach was employed to determine the better refrigerant choice between R32 and R134a for the heat pump, aside from other important factors that are considered when selecting the refrigerant, such as safety and environmental impacts. Comparing the results of R134a and R32 refrigerants, R134a has a higher GWP value than R32, indicating that R32 is more environmentally friendly. Regarding safety, R134a has low toxicity and flammability, while R32 exhibits low toxicity and mild flammability. Thus, R134a is considered safer than R32. Furthermore, the COP value of R134a was found to be higher than that of R32, indicating that R134a offers greater efficiency for the heat pump compared to R32.

SiRNAs pools generated in Escherichia coli exhibit strong RNA-interference activity against influenza virus genomic sequences

Due to the recurrent pandemic outbreaks that occurred during the last century, Influenza A viruses are considered a serious potential danger to human health.Among the innate immune pathways in eukaryotes, RNA interference plays a significant role in the interaction between viruses and host cells. RNA interference is addressed by small dsRNA molecules produced by the host itself (miRNAs, i.e. “micro-RNAs”) but can be triggered also by the administration of exogenous short RNAs (siRNAs, “short interfering RNAs”).In this work, artificial siRNA pools targeting NP and PB genomic regions of the Influenza virus were produced in engineered Escherichia coli, adapting a published protocol. In a MDCK cell in vitro model, these preparations were challenged against reporter vectors bearing viral genomic sequences. A strong and specific RNA interference activity was observed, and the details of this action were indagated.

Identification and domestication of native ornamental fishes of Begnas Lake, Pokhara, Nepal

Native fishes have great value as an ornamental fish in Nepal as well as in the global fair. Most of the ornamental fish species of Nepal are imported from India and Thailand. The main goal of this experiment is to identify and domesticate indigenous ornamental fishes for commercial production. Begnas area, Pokhara was selected as the study site as it has different small indigenous fish species which might have great potential as ornamental fish. The study was carried out for eight months period from February to September. Native fishes were collected from outlets and irrigation canal of Begnas Lake by using a cast net. Five fish species Puntius conchonius, Puntius sophore, Barilius barna, Danio devario and Danio rerio were identified and found suitable for ornamental purpose. These fish species were domesticated with different feed with maintaining the water quality parameters in an aquarium during the experiment period. Survivability of these fish species was low during the winter season; and at the same time, they could adapt to any kind of food. Danio devario was selected for the breeding purpose; and among all, 33 individuals were selected and placed in different conditions (-in the aquarium with heater and aerator, in the outer tank exposed to direct sunlight, the tank having continuous water flow without sunlight and in the open artificial pool) with 40% CP and bloodworms and maintaining the proper water quality. Out of all the different conditions, the environment that was artificially made pool with enough sunlight was found to be suitable for breeding. Their breeding was also influenced by the environmental condition since they bred one month later than their regular breeding periods in captive conditions.

Vocal complexity in Antillean manatees (Trichechus manatus manatus)

Abstract Vocal complexity can be expressed through variations in repertoire size, structure, and individual manatee repertoires. Here we aimed to assess the complexity of the vocal behaviour of Antillean manatees living in captivity (i.e., artificial pools) and in reintroduction enclosures (i.e., natural enclosures placed in an estuarine area). Specifically, we evaluated: (i) the structure of vocalisations to assess whether they had variants; (ii) the variation in call production (rate and pattern) between groups with different configurations; (iii) whether individuality occurred in vocalisation structure. We found four categories of vocalisations, of which two had different variants. Not all study groups produced all call categories and variants. Older and younger males in the reintroduction enclosures had the highest call rates compared to captive females and captive males. The vocal and behavioural patterns differed between groups. Squeak call structure differed between individuals. Such vocal complexity may aid manatees in adapting to their dynamic social and structural environment, facilitating communication.

Simple Floating Ocean Wave Energy Converter: Developing Teaching Media to Communicating Alternative Energy

Research aims to develop teaching media in communicating alternative energy to students who are in high school. The teaching media developed as a prototype converter of ocean wave energy into electrical energy. This Converter is focused on helping students understand concepts and technologies in utilizing ocean wave energy as an alternative energy source. The development stage adopted the ADDIE model, which is limited to the analysis, design, and development stages. The data obtained are in the form of design validation data, trial data, and product assessment data. The data were analyzed using descriptive statistics. Based on the results of data analysis, it is found that (1) the converter design is feasible to be developed with a few additions to the transmission section to produce higher RPM; (2) the resulting converter functions correctly with the output voltage of 5 to 9 volts in the artificial wave pool test and reaches 8 to 12 volts; (3) for product assessment, it was found that the Converter produced was suitable to be used as a teaching medium to communicate concepts and technology in utilizing ocean wave energy as an alternative energy source. So, teaching media in the form of a wave energy converter could be used as an alternative to communicating the concept of using ocean waves as an alternative energy source. The implication of this research is that it can be used as a model or initial example in developing learning media related to alternative energy and can even be used as a model in developing converters on a larger scale so that the wider community can use them.

A comprehensive review on solar pond research in India: Past, present and future

Solar pond is generally a shallow artificial pool of water in which considerable temperature can be established within its lower layers by suppression of convective transport. Generally, for prevention of convection, some suitable salt solution is used. In this paper, various aspects of solar pond, in terms of both simulation and experimental research advances, practical applications, economic features, challenges faced and future prospects, particularly with respect to Indian context have been reviewed. In general, the importance and the position of India at global level in terms of solar energy harvesting potential have been discussed. Apart from conventional uses of solar ponds in process heating and salt production, their applications in water distillation and thermoelectric power generation are also highlighted. Besides, stability aspect and its importance are revisited from simulations and experimental observations. Important identified areas requiring future research and development to recognize more technically feasible solar pond-based systems include organic Rankine cycle for electrical power production, crop drying, building cooling and air-conditioning based on absorption systems, thermoelectric cooling, and integration of solar ponds with other renewable energy resources. The present literature is proposed to offer guidelines in policy making aimed at addressing various societal requirements in a sustainable and affordable manner by utilizing available natural resources.