• 제목/요약/키워드: Kangwon-do

검색결과 1,397건 처리시간 0.037초

Rearing Temperature and Density Effects on the Number of Bacterial and Fungal Colonies in Metamorphosed Dybowski's Frogs (Rana dybowskii)

  • Kim, Jong-Sun;Choi, Woo-Jin;Park, Il-Kook;Koo, Kyo-Soung;Kang, Hui-Beom;Kwon, Oh-Sung;Lee, Seung-Hyeon;Choi, Hye-Ji;Lee, Jung-Hyun;Lee, Jin-Gu;Park, Dae-Sik
    • Journal of Forest and Environmental Science
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    • 제34권1호
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    • pp.61-65
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    • 2018
  • To know if small changes in rearing water temperature and density affect the number of bacterial and fungal colonies in metamorphosed frogs, Dybowski's frog tadpoles were reared from Gosner 25-26 stages at either low ($1^{\circ}C$ low to ambient water temperature), ambient, or high ($1^{\circ}C$ high) water temperature (each 15 tadpoles in 20 L water) condition and at either low (10 tadpoles/20 L water), medium (20 tadpoles), or high (30 tadpoles) density condition. Immediately after metamorphosis, we sampled bacteria and fungi from skin, liver, and heart of six metamorphosed frogs, randomly selected for each treatment group. After separate incubation of bacteria and fungi on 3M Petrifilm plates, we counted the number of bacterial and fungal colonies appeared on the plates and compared the numbers among the temperature and density treatment groups. For temperature treatment, high-temperature group had fewer bacterial colonies, while low-temperature group had more fungal colonies than the other two groups. For density treatment, low-density group had fewer bacterial colonies than the other two groups, but the number of fungal colonies were not different among the groups. Our results suggest that small increased rearing water temperature and lowered rearing density could potentially reduce pathogens in farming frogs.

An epidemiological survey on Cryptosporidium parvum infection of inhabitants in Chorwon-gun, Kangwon-do

  • Seo, Min;Huh, Sun;Chai, Jong-Yil;Yu, Jae-Ran
    • Parasites, Hosts and Diseases
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    • 제39권2호
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    • pp.201-203
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    • 2001
  • The present study was undertaken to know the infection status of Cryptosporidium parvum among the residents of Chorwon-gun, Kangwon-do in 1993. Total 461 fecal samples were collected from the inhabitants residing in Chorwon-gun during the period of August 12 to September 14, 1993. Fecal smears were prepared by formalin-ether sedimentation, and examined after modified acid fast staining. Of the 461 fecal samples,9 (1.9%) were positive for C. parvum oocysts. The positive cases were limited to thirties (4) patients, forties (3), and sixties (2) , and no oocyst was detected in other age groups. The oocyst positive rate for male was 1.4% and that of female was 2.6%.

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강원도 농업소유역의 지하수 및 지표수 수질의 계절적 변화에 관한 연구 (Groundwater and Small Stream Water Quality Changes of Rural Watersheds in Kangwon-do)

  • 최중대;이찬만;김도환
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 1998년도 학술발표회 발표논문집
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    • pp.558-564
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    • 1998
  • Flow rate, watertable and selected water quality of 2 small rural streams and 6 observation well located in Kangwon-do, Korea, were monitored land use of the watersheds was investigated to describe the trend of stream water quality for 2 years and groundwater quality for 1 year. Water qualities were analyzed with respect to BOD, SS, T-N, Nitrate, T-P and E-coli. Stream water quality and gorundwater quality directly concerned with the amount of rainfall and paddy fields. but water quality of watersheds is existed with other factor. Therefore, We have to continued monitoring and developing the best management practice.

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강원도산주요활엽수재(江原道産主要闊葉樹材)의 내후성(耐朽性)에 관(關)한 연구(硏究) (Studies on durability of major deciduous tree species grown in Kangwon-do)

  • 정대교;이원용
    • 한국산림과학회지
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    • 제4권1호
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    • pp.39-41
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    • 1965
  • (1) The durability of fifteen species of hard woods grown in Kangwon-do in relation to Polystictus Versecolor L. Fr. and Irpex consors Berk was studied. (2) The least affected hard wood species by Polystutus Versecolor L. Fr. were Q. serrata, C. crenata, M. amurensis, F. rhynchophylla and J. mandschrica; the moderatly affected species were Q. Variabilis, U. Davidiana var japonica, B. latiforia, C. controversa, P. padus and A. mono; and the most highly affected species were P. serrulata var. spondanea, S. obassia, T. amurensis and B. schmidtii. The least affected hard wood species by Irpex consors Berk, were U. Davidiana var japonica, C. crenata, M. amurensis, F. rhynchophylla, and J. mandshurica; the moderatly affected species were Q. Valiabilis, Q. serrata, P. serrulata var. spondanea, C. controversa, and A. mono; and the most highly affected species were B. latiforia, P. padus, S. obassia, T. amurensis, and J-mandshurica. (3) No difference was obscured on the durabilities on effected by kind of fungus. (4) Correlationship between specific gravity and durability of the woods was not significant.

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제비꽃속(제비꽃과)의 신종: 가지제비꽃(Viola ramiflora K. O. Yoo) (A new species of Viola (Violaceae): Viola ramiflora K. O. Yoo)

  • 김경아;이호;천경식;유기억
    • 식물분류학회지
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    • 제49권2호
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    • pp.140-144
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    • 2019
  • 제주도에서 제비꽃속의 신종인 가지제비꽃(Viola ramiflora K. O. Yoo)을 새로이 발견하여 기재 및 도해하였다. 가지제비꽃은 꽃이 연한 자색이고 잎이 삼각상 난형, 난형 또는 장타원형으로 엽병에 얕은 날개가 발달한다는 점에서 제비꽃계열의 털제비꽃, 서울제비꽃, 흰털제비꽃, 그리고 왜제비꽃과 비슷하나 폐쇄화와 개방화의 화경이 뚜렷하게 분지하며, 폐쇄화의 포엽이 장란형으로 신장하는 특징을 가져 신종으로 명명하였다.

고출력 MH 램프의 등가 모델링 (Equivalence Modeling of High Power MH Lamp)

  • 박종연;김기남;태도영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1621_1622
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    • 2009
  • 본 논문에서는 램프의 저주파 구동 시 램프를 해석하여, 수식적 등가 모델링하였다. 안정기 설계 시 대부분 램프를 순수 저항으로 등가 하여 설계하는 오류를 범하고 있다. 그로 인해 이론과 실험결과의 오차가 발생하여 안정기 설계 시 많은 어려움을 겪고 있다. 이 문제점을 해결하고자 램프의 정상상태를 세 가지 가정을 통해 이론적으로 쉽게 접근 하였으며, 실험을 통해 그 성능을 입증 하였다.

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철손을 고려한 SPMSM의 MTPA 제어 (A MTPA Control of SPMSMs Considering Core Losses)

  • 김도현;김상훈
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2018년도 전력전자학술대회
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    • pp.426-427
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    • 2018
  • 본 논문에서는 철손을 고려한 SPMSM(Surface mounted Permanent Magnet Synchronous Motor)의 모델로부터 출력 토크를 향상시킬 수 있도록 하는 개선된 MTPA(Maximum Torque Per Ampere) 제어 기법을 제안하였다. d축 전류를 0으로 사용하는 SPMSM의 기존 MTPA 제어 방식보다 철손을 고려한 MTPA 전류로 운전하는 제안된 방식이 더 큰 출력 토크를 얻을 수 있음을 800W PMSM에 대한 시뮬레이션을 통해 확인하였다.

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옵셋 전압을 이용한 일정 스위칭 주파수의 Random PWM 기법 (A novel Random PWM technique with a constant switching frequency utilizing an offset voltage)

  • 김도겸;김상훈
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2016년도 추계학술대회 논문집
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    • pp.212-213
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    • 2016
  • 본 논문에서는 옵셋 전압을 이용한 Random PWM 기법을 제안한다. 제안된 Random PWM은 일정 스위칭 주파수 하에서 유효벡터를 랜덤하게 위치시켜 고조파 스펙트럼(Spectrum)을 확산한다. 제안된 기법과 일반적인 PWM 기법의 고조파 스펙트럼 분포, Harmonic Spread Factor(HSF), Total Harmonic Distortion(THD)를 통해 제안된 Random PWM의 유효성을 확인하였다. 3.7kW 유도 전동기에 대한 실험을 통해 제안된 기법의 타당성을 검증하였다.

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