We present an electromagnetic linear vibration energy harvester with an array of rectangular permanent magnets as a springless proof mass. Instead of supporting the magnet assembly with spring element, ferrofluid has been used as a lubricating material. When external vibration is applied laterally to the harvester, magnet assembly slides back and forth on the channel with reduced friction and wear due to ferrofluid, which significantly improves the long-term reliability of the device. Electric power is generated across an array of copper windings formed at the bottom of the aluminum housing. A proof-of-concept harvester has been fabricated and tested with a vibration exciter at various input frequencies and accelerations. For the device where 5 μL of ferrofluid was used for lubrication, maximum output power of 493 μW has been generated, which was 4.37% higher than that without ferrofluid. Long-term reliability improvement due to ferrofluid lubrication has also been verified. For the device with ferrofluid, 1.02% decrease of output power has been observed, in contrast to 59.73% decrease of output power without ferrofluid after 93,600 cycles.
There are 60 species of blood-feeding land leeches, 50 species belonging to the family Haemadipsidae and 10 species belonging to the family Xerobdellidae. Despite recent papers on the land leeches, their taxonomic identification is not fully understood, especially at a species level. In Korea, there have been no historical records of the terrestrial leeches, but recently an unrecorded blood-feeding land leech was discovered at Gageo-do (Island), Korea. Molecular analysis was used to identify the species of 29 leeches collected from Mt. Dock-Sil in Gageo-do. Conventional PCR was conducted using nuclear 18S rRNA and mitochondrial cytochrome c oxidase subunit 1 (CO1) genetic marker. The 18S rRNA sequences revealed that the leeches share 99.9% identity with Haemadipsa rjukjuana (inhabiting Taiwan), and the CO1 sequences revealed that the leeches are very close to H. rjukjuana (inhabiting Taiwan). The CO1 sequences were separated into 2 categories, 1 with 94.6% and the other with 94.3% similarity to the H. rjukjuana L00115A (inhabiting Taiwan). This new finding of the land leech is the first record in Korea. In addition, the north range of the distribution of the blood-feeding leech (Hirudiniformes: Haemadipisidae) should be reconsidered including Korea.
Five species of the genus Protohyale belonging to the family Hyalidae were collected from shallow coastal waters of Korea. Prior to our study, only two species, P. (Boreohyale) pumila (Hiwatari & Kajihara, 1981) and P. (B.) triangulata (Hiwatari, 2003) had been reported from Korea. One of the collected species, Protohyale (B.) magnaocularis is identified as a new species. The morphology of the eyes, antenna 1, gnathopod 2, uropods and telson are the major characteristics which differentiate P. (B.) magnaocularis sp. nov. from its congeners. The remaining two species, P. (B.) kajiharai (Hiwatari, 2003) and P. (B.) latimana (Hiwatari, 2003) are recorded for the first time from Korea. Protohyale (B.) kajiharai, P. (B.) latimana and P. (B.) magnaocularis sp. nov. are fully described and illustrated. A key to the species of Protohyale (B.) from Korea is also provided.
Arisubathynella gen. nov. is established for a new species, A. cheongmiensis sp. nov. from South Korea. An illustrated description is given. The new genus stands out in the family Parabathynellidae by six-segmented antennules, three-segmented antenna without medial seta on inner margin of third segment, absence of mandibulartooth of the ventral edge, bare proximal segment of maxilla, two-segmented exopods of thoracopods II-VII, and male thoracopod VIII with elongated external lobe. Arisubathynella gen. nov. is the fourth genus known from South Korea and foreshadows the great diversity of bathynellaceans in the Far East.
We describe, diagnose and illustrate eight new species in the genus Anabarhynchus Macquart, 1848 as follows: Anabarhynchus cretatus sp. n., Anabarhynchus darembal sp. n., Anabarhynchus iancommoni sp. n., Anabarhynchus longiseta sp. n. Anabarhynchus lyncurium sp. n., Anabarhynchus moretonensis sp. n., Anabarhynchus neboensis sp. n. and Anabarhynchus wintertoni sp. n. These represent all new species in collections from south east Queensland. These new species bring the total number of described Australian species in the genus to 112.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.