• Journal of Species Research
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• v.5 no.3
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• pp.483-497
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• 2016

Nine new species of genus Ircinia (Demospongiae: Dictyoceratida: Irciniidae) from Jejudo Island, Korea are described. All of the new species are distinguished from the others reported species of Ircinia by the skeletal structure, especially massive fasciculate primary fibres. The characters of genus Ircinia have primary fibres cored with foreign debris and no cored secondary fibres. Primary fibres are not easy to distinguish from secondary fibres if they are not cored. Secondary web has perforated plate or meshed net. All new species have loosely arranged skeletal fibres network.

• Fibers and Polymers
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• v.4 no.1
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• pp.8-14
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• 2003

This paper considers the potential impact of biological approaches such as bio-copying (biomimetics) and biomanipulating (e.g. genetic engineering) on future developments in the field of textiles and, in particular, fibres. If analytical tools for studying biological systems combined with those of materials science are further developed, and higher efficiency and reproducibility of genetic engineering technology can be achieved, the potential for the copying and manipulation of nature for textile innovations will be immense. The present state for both fields is described with examples such as touch and close fastener, structurally coloured fibres, the Lotus of lect (for bio-copying), as well as herbicide tolerant cotton, insecticide resistant cotton (Bt cotton), cotton polyester bicomponent fibres, genetically engineered silkworm and silk protein, and spider fibres. (for genetic engineering).

• Computers and Concrete
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• v.20 no.1
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• pp.23-29
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• 2017

In this study engineered steel fibres used as reinforcement for concrete were characterized by number of key mechanical and spatial parameters, which are easy to measure and quantify. Such commonly used parameters as length, diameter, fibre intrinsic efficiency ratio (FIER), hook geometry, tensile strength and ductility were considered. Effective classification of various fibres was demonstrated using simple multivariate computations involving principal component analysis (PCA). Contrary to univariate data mining approach, the proposed analysis can be efficiently adapted for fast, robust and direct classification of engineered steel fibres. The results have revealed that in case of particular spatial/geometrical conditions of steel fibres investigated the FIER parameter can be efficiently replaced by a simple aspect ratio. There is also a need of finding new parameters describing properties of steel fibre more precisely.

• Advances in concrete construction
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• v.3 no.4
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• pp.283-293
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• 2015

This paper presents the effects of elevated temperatures of $400^{\circ}C$ and $800^{\circ}C$ on the residual compressive strength and failure behaviour of fibre reinforced concretes and comparison is made with that of unreinforced control concrete. Two types of short fibres are used in this study e.g., steel and basalt fibres. The results show that the residual compressive strength capacity of steel fibre reinforced concrete is higher than unreinforced concrete at both elevated temperatures. The basalt fibre reinforced concrete, on the other hand, showed lower strength retention capacity than the control unreinforced concrete. However, the use of hybrid steel-basalt fibre reinforcement recovered the deficiency of basalt fibre reinforced concrete, but still slightly lower than the control and steel fibres reinforced concretes. The use of fibres reduces the spalling and explosive failure of steel, basalt and hybrid steel-basalt fibres reinforced concretes oppose to spalling in deeper regions of ordinary control concrete after exposure to above elevated temperatures. Microscopic observation of steel and basalt fibres surfaces after exposure to above elevated temperatures shows peeling of thin layer from steel surface at $800^{\circ}C$, whereas in the case of basalt fibre formation of Plagioclase mineral crystals on the surface are observed at elevated temperatures.

• Animal Systematics, Evolution and Diversity
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• v.36 no.2
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• pp.143-153
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• 2020

Six new species of two genera Dysidea and Pleraplysilla (Demospongiae: Dictyoceratida: Dysideidae) are described from Jejudo Island, Dokdo Island and Guryongpo, Korea. Among them, five new species of the genus Dysidea are compared with other reported species in fibres structure, cored detritus and fibres arrangement. Dysidea niveus n. sp. is characterized by thin collagenous plate-like fibres. Dysidea dokdoensis n. sp. is similar to D. geomunensis Kim et al., 2020 in skeletal structure, but differs in length of surface conules. Dysidea hydra n. sp. is similar to D. mureungensis Kim et al., 2020 at the surface, but differs in fibres cored with spicules. Dysidea sabulum n. sp. is similar to D. glavea Kim et al., 2020 in cored large sands in fibres, but differs in having numerous large sands cored in fibres throughout the sponge. Dysidea hirsuta n. sp. is unique, only surface fibres cored with large sands but not in choanosome. A new species of genus Pleraplysilla, P. flabellum n. sp. is compared with seven other reported species. This new species is not encrusting but has a thick flabellate shape.

• Animal Systematics, Evolution and Diversity
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• v.30 no.1
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• pp.16-21
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• 2014

Four new species of the genus Hyattella (Dictyoceratida: Spongiidae); H. sinchangensis n. sp., H. mara n. sp., H. chuja n. sp. and H. lendenfeldi n. sp., were collected from Jeollanam-do and Jeju-do, Korea. Hyattella sinchangensis n. sp., H. mara n. sp., H. chuja n. sp. and H. grobosa Lendenfeld, 1889 are very similar to each other in some characters. However, Hyattella sinchangensis n. sp. characterized by no special dermal lamella and no tertiary fibres, and more thin secondary fibres than H. globosa. Hyattella mara n. sp. is differs in having well developed dermal lamella, slightly fasciculated primary fibres, and thick tertiary fibres. Hyattella chuja n. sp. differs in surface characters with a slightly elevated part, skeleton with abundant spongine, and very complex meshes. Hyattella lendenfeldi n. sp. is similar to H. tenella (Lendenfeld, 1889) in skeletal structure, thickness of primary and secondary fibres, but differs in growth form.

• Advances in concrete construction
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• v.5 no.2
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• pp.173-182
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• 2017

This paper is aimed at determining the shear and impact strength of waste plastic fibre reinforced concrete. M30 grade of concrete is prepared with waste plastic door fibres cut into 5 mm width and aspect ratios of 30, 50, 70, 90 and 110. Fibres are used in a volume fraction of 0 to 1.5% with an increment of 0.25%. L shaped specimens are cast for shear strength tests and flat plates of size $250{\times}250{\times}30mm$ are used for impact tests. "Drop ball method" is used for checking the impact strength. Shear strength is checked with L shaped specimens under UTM with a special attachment. It was found that up to 1.25% of waste plastic fibres can be effectively used for better strength of concrete both in shear and impact. Shear and impact strength were found to be increasing up to a volume fraction of fibres of 1.25%.

• Advances in concrete construction
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• v.1 no.4
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• pp.305-318
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• 2013

Engineering properties such as compressive strength, splitting tensile strength, modulus of rupture, modulus of elasticity and Poisson's ratio of geopolymer concrete (GPC) and steel fibre reinforced geopolymer concrete (SFRGPC) have been obtained from standard tests and compared. A total of 15 specimens were tested for determining each property. The grade of concrete used was M 40. The percentages of steel fibres considered include 0.25%, 0.5%, 0.75% and 1%. In general, the addition of fibres improved the mechanical properties of both GPC and SFRGPC. However the increase was found to be nominal in the case of compressive strength (8.51%), significant in the case of splitting tensile strength (61.63%), modulus of rupture (24%), modulus of elasticity (64.92%) and Poisson's ratio (50%) at 1% volume fraction of fibres. An attempt was made to obtain the relation between the various engineering properties with the percentage of fibres added.

• Advances in concrete construction
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• v.9 no.5
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• pp.479-489
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• 2020

Studies have proved that the mechanical properties of concrete, suddenly is dropped off with employing waste materials as replacements. The effectiveness of fibre addition on the structural stability of concrete has been indicated in recent investigations. There are different waste aggregates and fibres as plastic, rubber tire, coconut, and other natural wastes, which have been evaluated throughout the last decades. The fibres incorporation has a substantial effect on the properties of concrete mix subjected to different loading scenarios. This paper has reviewed different types of wastes and the effect of typical fibres including Poly Ethylene Terephthalate (PET), rubber tire, and waste glass. Furthermore, waste plastic and waste rubber has been especially studied in this review. Although concretes containing PET fibre revealed a reduction in compressive strength at low fibre fractions, using PET is resulted to micro-cracking decrement and increasing flexibility and flexural strength. Finally, according to the reviews, the conventional waste fibres are well-suited to mitigated time-induced damages of concrete and waste fibres and aggregates could be a reliable replacement for concrete.

• Animal Systematics, Evolution and Diversity
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• v.30 no.3
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• pp.196-205
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• 2014

This paper describes six new species of sponges in the genus Agelas from Kosrae Island, The Federated States of Micronesia. Most Agelasid sponges are known from only tropical regions. All the new Agelas species; A. fragum n. sp., A. kosrae n. sp., A. purpurea n. sp., A. bakusi n. sp., A. vansoesti n. sp. and A. incrustans n. sp. are compared with other valid species that were studied. Six new species differ from the other species by morphology, growth form, skeletal fibres, habitats and spicule size. Agelas fragum n. sp. is characterized by its tuberculate surface and primary fibres with brush-like spicules. Agelas kosrae n. sp. is differs in skeletal structure and have tertiary fibres. Agelas purpurea n. sp. is characterized by primary, secondary and tertiary fibres are all cored with spicules. Agelas bakusi n. sp. is similar to Agelas clathrodes in shape, but differs in the primary fibres. Agelas vansoesti n. sp. is characterized by having acanthostrongyles. Agelas incrustans n. sp. is distinguished by its encrusting and not cavernous interior.