• 제목/요약/키워드: Co-presence

검색결과 1,741건 처리시간 0.035초

Magnetic CoFe2O4 Nanoparticles as an Efficient Catalyst for the Oxidation of Alcohols to Carbonyl Compounds in the Presence of Oxone as an Oxidant

  • Sadri, Fariba;Ramazani, Ali;Massoudi, Abdolhossain;Khoobi, Mehdi;Azizkhani, Vahid;Tarasi, Roghayeh;Dolatyari, Leila;Min, Bong-Ki
    • Bulletin of the Korean Chemical Society
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    • 제35권7호
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    • pp.2029-2032
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    • 2014
  • Magnetically nano-$CoFe_2O_4$ efficiently catalyzes oxidation of primary and secondary benzylic and aliphatic alcohols to give the corresponding carbonyl products in good yields. The reactions were carried out in an aqueous medium at room temperature in the presence of oxone (potassium hydrogen monopersulfate) as an oxidant. In addition, the catalysts could be reused up to 6 runs without significant loss of activities. Catalyst was characterized by SEM, XRD and IR.

First Report of Echinococcus equinus in a Donkey in Turkey

  • Simsek, Sami;Roinioti, Erifylli;Eroksuz, Hatice
    • Parasites, Hosts and Diseases
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    • 제53권6호
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    • pp.731-735
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    • 2015
  • A 2-year-old female donkey (Equus asinus) was euthanized in the Pathology Department of Firat University, Elazig, Turkey. Necropsy disclosed the presence of 7 hydatid cysts distributed throughout the lung parenchyma. One of those cysts represented the parasite material of the present study and was molecularly identified through sequencing of a fragment of cytochrome c oxidase subunit 1 (CO1) and nicotinamide adenine dinucleotide dehydrogenase subunit 1 (NADH1) gene, as Echinococcus equinus. The generated CO1 sequence supports the presence of the dominant haplotype as has been described in Europe and Africa. The NADH1 sequence was found similar to sequences reported in equids in Egypt and the United Kingdom. The molecular identification of E. equinus in a donkey is being reported for the first time in Turkey.

The Predation Impact by the Heterotrophic Dinoflagellate Protoperidinium cf. divergens on Copepod eggs in the Presence of Co-occurring Phytoplankton prey

  • Jeong, Hae-Jin
    • Journal of the korean society of oceanography
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    • 제31권3호
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    • pp.144-149
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    • 1996
  • I investigated the predation impact by the heterotrophic dinoflagellate Protoperidinium cf. divergens on copepod eggs in the presence of co-occurring phytoplankton prey (a preferred red-tide dinoflagellate Gonyaulax polyedra) and the selective feeding on mixtures of both prey. The ingestion rates of P. cf. divergens on Egg N (unidentified round copepod eggs with a smooth surface, about 80 in diameter) decreased by only 1.7-2 times when mean G. polyedra concentration increased by 57-115 times. In mixed prey experiments, P. cf. divergens preferred Egg N over G. polyedra even at 1.1 ${\mu}g$C $ml^{-1}$ or 470 cells $ml^{-1}$ of the latter. A strong preference of P. cf. divergens for Egg N over G. polyedra can be responsible for this relatively small effect. Protoperidinium may sometimes have a considerable predation impact on the populations of Egg N even during phytoplankton blooms or red-tide periods.

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Electrolyte Effect on the Particle Characteristics Prepared by Soap-Free Emulsion Polymerization

  • Han, Seung-Tak;Lee, Kang-Seok;Shim, Sang-Eun;Saikia, Prakash J.;Choe, Soon-Ja;Cheong, In-Woo
    • Macromolecular Research
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    • 제15권5호
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    • pp.403-411
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    • 2007
  • Monodisperse micron-sized polystyrene (PS) spheres were successfully obtained using a single stage soap-free emulsion method in aqueous media mixed with ethanol (co-solvent) containing NaCI as the electrolyte. The optimum conditions for preparing the monodisperse PS microspheres, using soap-free emulsion polymerization in a water/ethanol mixture with an electrolyte, were studied. The presence of the co-solvent and electrolyte controlled the particle dispersion stability during the polymerization. The microspheres formed using PS, with a weight-average diameter of $2.6{\mu}m$, coefficient of variation of 5.3% and zeta potential of -15.1 eV, were successfully obtained in the presence of 0.1 wt% NaCI, 10 wt% monomer, 0.1 wt% initiator and 95/5 (g/g) of a water/ethanol mixture reacted at $70^{\circ}C$ for 24 h.

유사홀로그램 가시화 기반 가상 휴먼의 제스쳐 상호작용 영향 분석 (Exploring the Effects of Gesture Interaction on Co-presence of a Virtual Human in a Hologram-like System)

  • Kim, Daewhan;Jo, Dongsik
    • 한국정보통신학회논문지
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    • 제24권10호
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    • pp.1390-1393
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    • 2020
  • Recently, a hologram-like system and a virtual human to provide a realistic experience has been serviced in various places such as musical performance and museum exhibition. Also, the realistically responded virtual human in the hologram-like system need to be expressed in a way that matches the users' interaction. In this paper, to improve the feeling of being in the same space with a virtual human in the hologram-like system, user's gesture based interactive contents were presented, and the effectiveness of interaction was evaluated. Our approach was found that the gesture based interaction was provided a higher sense of co-presence for immersion with the virtual human.

Coordinatively Polymerized Bilayer Membranes Prepared with an Amphiphilic Derivative of 2-Thiazolyazophenol in Water

  • 서정훈;신승훈;심현보
    • Bulletin of the Korean Chemical Society
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    • 제18권2호
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    • pp.190-193
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    • 1997
  • In search of new amphiphiles that form coordinatively polymerized bilayer membranes (CPBMs) in water, N-dodecyl-3-[2-hydroxy-3-(4-carboxymethyl-2-thiazolylazo)-5-methylphenyl]propanamide (5) was prepared. The bilayer membranes of 5 prepared in the presence of 2 equivalents of NaOH were further sonicated in the presence of transition metal ions such as Ni(Ⅱ), Cu(Ⅱ), Co(Ⅱ), or Co(Ⅲ) at > 80 ℃ to obtain CPBMs. The CPBMs of 5 were characterized by transmission electron microscopy, gel filtration, resistivity against disruption in aqueous ethanol, visible spectra, and release of entrapped 5(6)-carboxyfluorescein. Remarkable stabilization of the bilayer membranes through coordinative polymerization was evidenced by the resistivity of the Ni(Ⅱ)-CPBM of 5 against disruption in 40%(v/v) ethanol upon incubation for 20 hr.

A New Record of Porcellio scaber (Isopoda: Oniscidea: Porcellionidae) from South Korea, with Notes on Its Variation

  • Song, Ji-Hun
    • Animal Systematics, Evolution and Diversity
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    • 제36권4호
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    • pp.309-315
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    • 2020
  • The common rough woodlouse Porcellio scaber Latreille, 1804 is newly reported from South Korea with following diagnostic characteristics: the presence of distinct tubercles on body; the strongly developed lateral lobes of head; the presence of notch on tracheal field of pleopod 1 exopod; and distinctly short exopod of uropod. This species is reported to be cosmopolitan, but there were no taxonomic records of it in South Korea. All voucher specimens were collected from humid shaded areas adjacent to the eastern coast of South Korea. Organismal ecology and scanning electron microscope photographs are provided. In addition, the results of CO1 analysis of individuals representing the different color and morphological variations are provided.

원격지 공간 가상 휴먼 가이드 영향 분석 (Effects on the Virtual Human Guide of Remote Sites)

  • Chung, Jin-Ho;Jo, Dongsik
    • 한국정보통신학회논문지
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    • 제26권8호
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    • pp.1255-1258
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    • 2022
  • Recently, immersive VR/AR contents have actively increased, and various services related to VR/AR allow users to experience remote places. For example, if failure situations occur frequently in factory of the remote site, mixed reality (MR) with a synthetic virtual human expert in reconstructed remote location can help immediate maintenance task with interaction between the operator and the virtual expert. In this paper, we present a technique for synthesizing the virtual human after capturing a 360-degree panorama of a remote environment, and analyze the effects to apply a method of guiding virtual human by interaction types. According to this paper, it was shown that co-presence level significantly increased when verbal, facial expression, and non-verbal animation of the virtual human was all expressed.

원격협업 시스템에서 협력자 눈 시점 공유 (Sharing Eye Gaze in Mixed Reality Remote Collaboration System)

  • 정재준;김승원
    • 스마트미디어저널
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    • 제11권6호
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    • pp.30-36
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    • 2022
  • 본 논문은 원격협업 시스템에서 시각적 의사소통 도구인 눈 시점 포인터 공유의 장점을 알아보았다. 특히 원격 협력자의 손동작이 가상 손으로 공유될 때, 추가로 공유된 원격 협력자의 시점 포인터가 미치는 영향을 조사하였다. 24명의 피실험자가 참여한 사용자 실험에서, 추가된 원격 협력자의 눈 시점 포인터는 현지 협력자와 원격 협력자 모두의 작업 부하를 줄여주었으며 두 협력자 간 co-presence를 높여주었다.

중층심해에 분사된 액체 이산화탄소 하이드레이트 용해에 대한 연구 (Study on the Dissolution Behavior of Liquide $CO_2$ Hydrate Injected at the Intermediate Depth of the Ocean)

  • 김남진;박성식;서향민
    • 신재생에너지
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    • 제4권2호
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    • pp.12-20
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    • 2008
  • Calculations for the dissolution behavior of liquid CO2 droplets released in the East Sea and the Clipperton Clarion from a moving ship and a fixed pipeline have been carried out in order to estimate the CO2 dissolution characteristics in the ocean. The results show that the injection of liquid CO2 from a moving ship in a high temperature point is an effective method for dissolution. Also, it is noted that the ultimate plume generated from CO2 bubbles repeatsand shrinking due to the peeling from a fixed pipeline, and the presence of hydrate layer on a liquid CO2 droplet acts as a resistant layer in dissolving liquid CO2.

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