530 research outputs found
Solar distillation meets the real world: a review of solar stills purifying real wastewater and seawater
No full textSolar energy-driven evaporation-based freshwater production is one of the sustainable ways to purify contaminated/salty water. Recent advances in solar absorbers’ assemblies, design modifications, and integrations with heating sources improved the rate of freshwater productivity. However, the type of feed water affects the evaporation rate in a solar desalination system (SDS). Many studies used tap water with added contaminants to test the performance of a SDS and studied the water quality improvement. As a typical result, pH, total dissolved solids (TDS), and electrical conductivity (µS/cm) are reduced after solar evaporation. The performance of SDSs for real wastewaters are also important to understand, e.g., the reduction of high organic pollutants after solar evaporation. In this aspect, the main objective of the present work is to review solar distillation of real wastewaters and seawater by using SDSs. Further, the mechanism of a solar distiller with heat transfer principles, parameters affecting evaporation process, real wastewaters and seawaters purified in a solar distillation system, improvement of various parameters before and after solar evaporation, pathways of handling wastewaters, challenges, and future perspectives are discussed. Conclusively, SDSs are found to remove pollutants effectively after solar evaporation. The evaporation rate is relatively slower due to high concentration of pollutants that reduce vapor pressure. The COD removal of various real wastewaters, including sludge, kitchen, textile, palm oil, petroleum, water plant, and municipal wastewaters, was 98.13%, 97.85%, 96.84%, 96.71%, 87.99%, 86.99%, and 85.67%, respectively. The reduction rate of salt concentration in real seawater after evaporation in the solar distiller was 99.99%.11Nsciescopu
A review on efficiently integrated passive distillation systems for active solar steam evaporation
No full textSolar energy-driven desalination is one of sustainable means to produce reusable water. Recently, solar distiller formally known as a solar still (SS) has been commonly employed to get freshwater through evaporation and consequent condensation process. However, such passive systems are typically slow on the distillation process, because bulk heating requirement and other energy losses. To increase the fresh water productivity of the passive distillation systems, researchers have usually adopted concentrators, reflecting mirrors, evacuated tube collectors (ETC), energy absorbing-engineered nanoparticles and energy storage (sensible and latent heat) materials. In this manner, water in a distiller can obtain additional heat and speedy evaporation take place immediately. Thus, efficient integration of passive distillation is highly useful to achieve appreciable production rate of fresh water for human daily needs. In this aspect, many researchers continuously tried to develop new innovative technologies for effective solar desalination. The main objective of this assessment is to review the current integration strategies and consequences for improving the productivity of solar distillers. Here, the term integration comprises additional heat sources, including heat confinement to broadband nanoparticles (micro-integration), concentrators, reflecting-mirrors (macro-integration), latent heat storage (LHS), sensible heat storage (SHS), and wicking cloth-based absorbers. This review exclusively focused on the newest results in the year of 2020–2021. In addition, the challenges, limitations, and requirements for future prospects are discussed.11Nsciescopu
T a b l e 2 in Barilius Kamjongensis, A New Bariliine Fish Species (Danionidae, Danioninae) From The Chindwin Basin Of Manipur, India
No full textT a b l e 2. Morphometric data of Barilius kamjongensis sp. n. (No. of specimens = 6)Published as part of <i>Arunkumar, L., Thoibi, M. & Jajo, E., 2023, Barilius Kamjongensis, A New Bariliine Fish Species (Danionidae, Danioninae) From The Chindwin Basin Of Manipur, India, pp. 65-74 in Zoodiversity 57 (1)</i> on page 68, DOI: 10.15407/zoo2023.01.065, <a href="http://zenodo.org/record/7841293">http://zenodo.org/record/7841293</a>
sj-doc-2-pib-10.1177_09544054221112144 – Supplemental material for The experimental investigation of springback and roughness parameters in the three-point forming process using terpolymer punch
No full textSupplemental material, sj-doc-2-pib-10.1177_09544054221112144 for The experimental investigation of springback and roughness parameters in the three-point forming process using terpolymer punch by T Arunkumar, M Ravichandran, M Varatharajulu and T Maridurai in Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture</p
sj-doc-1-pib-10.1177_09544054221112144 – Supplemental material for The experimental investigation of springback and roughness parameters in the three-point forming process using terpolymer punch
No full textSupplemental material, sj-doc-1-pib-10.1177_09544054221112144 for The experimental investigation of springback and roughness parameters in the three-point forming process using terpolymer punch by T Arunkumar, M Ravichandran, M Varatharajulu and T Maridurai in Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture</p
A review on carbonized natural green flora for solar desalination
No full textSolar desalination is one of the green energy processes to treat saline water and wastewater. Solar evaporation systems, formally solar stills, have been widely used to evaporate water to purify it. However, the evaporation rate in solar stills is typically low due to incoming energy used to heat the entire bulk water. In order to minimize the bulk heating, researchers have developed capillary flow-based, self-floatable, broadband photothermal absorbers (250–2500 nm wavelength) for fast solar evaporation. Recently, interfacial solar steam generation (ISSG) has attracted attention due to significant advantages in desalination and water treatment. In general, ISSG materials are classified into plasmonic metals, semiconductors, black carbon and polymer-based materials. The basic requirements for these photothermal materials include being self-floatable and having high solar absorption, fast water transport (capillary action) and low thermal conductivity to confine the heat locally. Some natural plant species satisfy these prerequisites and have been used as photothermal materials in solar steam generation (SSG). The present review exclusively focuses on the carbonized botanical species, including bamboo, corncob, corn-stalk, coconut-husk, carrot, fruit residues (cherry, grape, orange and apple), green algae, loofah fruit, magnolia fruit, mushroom, lotus leaf and seedpods, sugarcane, sunflower head, tofu, wheat flour and wood pieces for improving the evaporation rate and efficiency. Carbonization technique improves the solar absorption by increasing the carbon concentration. In addition, these floatable solar absorbers evaporate the water with the aid of natural microchannels. These materials not only improve the efficiency, but also have economic and environmental benefits.11Nsciescopu
Barilius kamjongensis Arunkumar & Thoibi & Jajo 2023, sp. n.
No full textBarilius kamjongensis sp. n. (fig. 1) urn:lsid:zoobank.org:act: 61794FCD-7D88-4B2E-B541-1B9CC4326D14 Material. Type. Holotype: 125/NH/ MUM, 27.II.2021, 24°86´N & 94°50´E, 101.1 mm SL, 111.7 mm TL, Taret-lok at Lunbung, Kamjong District, Manipur, India, Coll. Ersilia Jajo & her party. Paratypes: 125/NH/ MUM, 5 exs, 75.5–97.2 mm SL, 96.5–121.6 mm TL, data as for holotype. Diagnosis. Barilius kamjongensis sp. n. differs from its congeners based on the following combination of characters: presence of 2 pairs of barbels, 16–19 predorsal scales, 12–15 lateral body bars, inter-bars wider than bars, 40–43 perforated lateral line scales, 7.5/2.5 lateral line transverse scales, dorsal-fin without a distinct transverse blue-black band, origin of dorsal-fin closed to base of caudal-fin, not equidistant from the middle of eye and base of caudal-fin and far behind the vertical through the origin of pelvic-fin, pectoral-fin shorter than head length, pelvic-fin origin far in front of dorsal-fin origin, caudal-fin unequal lobes, body depth at dorsal-fin origin 22.8–26.6 % SL, caudal peduncle depth depth 8.5–10.3 % SL, predorsal length 55.8–57.7 % SL, head length 23.4–25.4 % SL, head length at occiput 12.5–18.4 % SL and 75.7–77.8 % HL, narrow head 10.4–12.7 % SL, eye diameter 6.4–7.9 % SL and 26.0–33.6 % HL respectively. See detailed comparison in the Discussion below. Description. Morphometric data are shown in table 1 and table 2. Body shape is shown in fig. 1. Body laterally compressed, ventral profile slightly rounded Post dorsal region in a slanted straight line. Head length usually longer and larger than head depth. Snout tip nearby blunt. Mouth gape below anterior margin of eye and mouth upturned, upper and lower jaws more or less same in length. Dentary tubercles of row developed and shown in fig. 2. Snout slightly longer than eye diameter. Inter-orbital region slightly convex. Nares located closed to eyes than tip of snout. Dorsal margin of eye never reaches to the dorsal profile of head and its lower margin never reaches to the level of angle of mouth. Origin of dorsal-fin closed to the base of caudal-fin, not equidistant from the middle of eye and base of caudal-fin but equal to the post-orbit and base of caudal-fin. Tip end of dorsal-fin straight, with posterior tip surpassing vertical through posterior base of anal-fin. Dorsalfin with ii, 7 rays. Pectoral-fin shorter than head length and often reaching base of pelvicfin. Pectoral-fin with i, 11 rays. Pelvic-fin origin far in front of dorsal-fin origin, its tip not reaching origin of anal-fin. Pelvic-fin with I, 7–8 rays Pectoral and pelvic-fins with lobate axial scales. Anal-fin originated far behind vertical through the last posterior origin of dorsal-fin ray with ii, 10 rays. Caudal-fin unequal, lower lobe longer than upper lobe and ii, 8+8. Ii rays. Circumpeduncular scales 14. Colouration. In fresh specimen, dorsal and dorso-lateral surfaces of head and body faintly greyish green, ventral portion anterior to pelvic-fin origin silver coloured. Belly creamy to light golden yellowish. Lateral body with 12–15 dark blue bars and not touched lateral line scales. Pectoral, pelvic and anal-fins are light orange in colour. Caudal-fin edge yellowish with blackish upper and lower lobe margins. Local Name. ‘Ngapaila’ in Tangkhul language and ‘Ngawa’ in Manipuri language. D i s t r i b u t i o n a n d h a b i t a t. Barilius kamjongensis sp. n. is presently known only the Taret-lok River, Kamjong District of Manipur (fig. 3–4). Taret-Lok River is originated from Nungshit-Haibi, then it joins the Nungjaopokpi River, southern part of Sita village, Tengnoupal District and flows through Tuyungbi at Yongkhun village which mainly dominated by Maring tribe and then joined to the Maklang River at Nambasi. There are three main hill streams of Nambasi viz., Lungbung, Kartangtak and Lungkuna which are the main hill stream fishing centres of the Taret-lok River of Kamjong District of Manipur. B. kamjongensis sp. n. is associated with the following fish species viz., Garna moyonkhulleni, Neolissochilus hexagonolepis, Poropuntius burtoni, Schistura reticulata, Glyptothorax chivomensis and Amblyceps sp. E t y m o l o g y. The species is named after the Kamjong District of Manipur from where it was collected.Published as part of Arunkumar, L., Thoibi, M. & Jajo, E., 2023, Barilius Kamjongensis, A New Bariliine Fish Species (Danionidae, Danioninae) From The Chindwin Basin Of Manipur, India, pp. 65-74 in Zoodiversity 57 (1) on pages 66-70, DOI: 10.15407/zoo2023.01.065, http://zenodo.org/record/784129
Experimental Enhancement of Heat Transfer Analysis on Heat Pipe using SiO2 and TiO2 Nano Fluid
No full textThis paper describes the enhancement of thermal performance of heat pipe using SiO2 and TiO2 nano fliuds. The experimentation explains about the effects of heat pipe inclination and heat input on the thermal efficiency and thermal resistance. Heat pipe is an advance type of heat exchanger which transfers huge amount of heat due to the effect of capillary action and phase change heat transfer principle. Recent developments in the heat pipe with high thermal conductivity through nano fluids. This paper reviews, influence of various factors such as heat pipe tilt angle, charged amount of working fluid, nanoparticles type, size, mass volume fraction and its effect on the improvement of thermal efficiency, heat transfer capacity and reduction in thermal resistance. The nano fluid preparation and the analysis of its thermal characteristics also have been reviewed. Arunkumar. G | Dr. P. Navaneetha Krishnan | Dr. T. Senthil Kumar "Experimental Enhancement of Heat Transfer Analysis on Heat Pipe using SiO2 and TiO2 Nano Fluid" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-4 , June 2018, URL: https://www.ijtsrd.com/papers/ijtsrd13094.pd
Preserving Privacy in Mobile Environments
No full textTechnology is improving day-by-day and so is the usage of mobile devices. Every activity that would involve manual and paper transactions can now be completed in seconds using your ngertips. On one hand, life has become fairly convenient with the help of mobile devices, whereas on the other hand privacy of the data and the transactions occurring in the process have been under continuous threat. Mobile devices connect to a number of service providers for various reasons. These could include downloading data, online purchasing or could be just used to browse information which may be irrelevant at a later point. Access to critical and sensitive information may be available at a number of places. In case of a mobile device, the information may be available with the service provider. Service Provider could be in the form of any web portal. In all such scenarios, passing the information or data from the service provider into the mobile device is a major challenge, as the data/information cannot be sent in plain text format. The con dentiality and integrity of the data needs to be protected and hence, the service provider must convert the data into an encrypted format before passing it onto the mobile device, to prevent risks from sniffing and unauthorized disclosure of data. Preserving the location of the individual user of any mobile device has also been the concern for a number of researchers.
Mobile devices have become an important tool in modern communication. Mobile and other handheld devices such as ipads and tablets have over taken laptops and desktops and hence there has been an increasing research interest in this area in recent years. This includes improving the quality of communication and the overall end-to-end data security in day-to-day transactions. Mobile devices continuously connect to di erent service providers for day-to-day needs such as online purchases, online banking and endless sur ng for information. In addition to this devices could be connecting to the service providers to receive or send sensitive information. At the Service Provider end, the data would be stored with the provider and Service Provider would only hand over the data if it con rms that the person requested it is authorized to receive the information. The exchange of data from one end of the network to the other is a major challenge due to malicious intruder mishandling of the data. Hence the con dentiality and integrity of the data needs to be protected either by transforming the sensitive information into a non-readable format or by converting into a cipher text.
Privacy has been an open problem for research as more and more information is getting leaked on a day-to-day basis. Through this thesis, I have tried to address a number of areas within the privacy realm where information and data access and sharing is a key concern along side the key aspect of location privacy. I have also tried to address the problems in the space of access control wherein I have proposed policy based languages and extensions for ensuring appropriate access control methodologies. The main goal and focus in this work has been to enforce the importance of location privacy in mobile environments and to propose solutions that resolve the problems of where and when to enforce location security. Another key goal of this work has been to create new access control and trust based solutions to ensure the right level of access to the right receiver of information. Through my research, I have explored the various privacy related attacks and suggested appropriate countermeasures for the same. In addition to proposing and showcasing solutions using policy languages for access control, I have also introduced geospatial access control solutions to ensure that the right user is accessing or requesting for the right information from the right location. This helps the appropriate and the right use of the information by the right resource. Through my thesis I have also given equal importance to the trust aspects of sharing information. I have created new trust assessment models to show how fused information can be handled and how can trust be imposed on the information provider and the information itself.
The main contribution of this thesis is to address the problems around protecting the data and individual's privacy and to propose solutions to mitigate these issues using new and novel techniques. They can be detailed as the following:
In privacy, there is always a privacy versus utility tradeo and in order to make use of utility, trust in the location is essential. Through this research I have developed i) novel attestation models and access control methodologies including Privacy Preferences Platform (P3P) extensions, ii) Extensible Access Control Markup Language (XACML) extensions and iii) Geospatial access control through GeoXACML. iv)I have created new methodologies to enforce location privacy and shown where best to enforce privacy. v)I have also shown that global attestation is very crucial for privacy and needs accurate methods in place to attest user's location information for access. vi) Fusing of location information is very crucial as there could be a number of similar or con icting information produced about a common source and it is very important to assess and evaluate the trust level in the information. I have proposed, developed and implemented a new trust assessment framework. This framework looks at the incoming information and passes it on to the rule engine in the framework to make some inferences and then the trust assessment module computes the trust score based on forward chaining or background chaining scheme. The framework is used to evaluate the trust on the fused information in a streaming setup. vii) I have created new solutions to look at the similarity pro les and create identity enforcement through pro ling. I have shown methods of anonymisation for location privacy and identity privacy
Experimental Investigation on Mineral Content of Fly Bottom Ash and Strength Characteristics of Fly Bottom Ash Bricks - A Review
No full textThis investigation is to study the mineral contents of fly bottom ash. After many years of research in sustainable construction materials, the quality of producing construction materials has significantly improved. And the replacement of ordinary cement with fly bottom ash has showed several improvements such as strength and other characteristics. During the production of ordinary cement, CO2 emissions are very high and energy consumption is also very high. Due to limited resources of nature, it has to be reconsidered to use the ordinary cement. The advancement of technologies has led to significantly promote the use of fly bottom ash in ordinary cement in order to improve the quality of construction materials. The fly ash is been used for zeolite synthesis, synthetization of organic geo polymer and in manufacturing of construction materials. Arunkumar. G | Jai Kumaresh. B | Arokia Jerome. D | Parameswaran. P | Rajkumar. T "Experimental Investigation on Mineral Content of Fly Bottom Ash and Strength Characteristics of Fly Bottom Ash Bricks - A Review" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-1 , December 2018, URL: https://www.ijtsrd.com/papers/ijtsrd19064.pd
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