• 제목/요약/키워드: Predominant Period

검색결과 288건 처리시간 0.02초

우포늪 범람에 의한 먼지벌레류(딱정벌레목, 딱정벌레과)의 다양성과 종조성 변화 (Change of Carabid Beetle (Coleoptera, Carabidae) Diversity and Species Composition after Flooding Events in Woopo Wetlands)

  • 도윤호;장민호;김동균;주기재
    • 생태와환경
    • /
    • 제40권2호
    • /
    • pp.346-351
    • /
    • 2007
  • Change of carabid beelte (Coleoptera, Carabidae) diversity and population structures in Woopo Wetlands (Changneung-Gun, Gyeungsangnam-Do, S. Korea) were investigated after flooding events. During the investigation period, 11 species belonging to five genera were identified. Dolichus halensis halensis(Schaller), Chlaenius (Ch.) pallipes Gebler, Ch. (Ilaenchus) naeviger Morawitz, and Pheropsophus (Stenaptinus) jessoensis Morawitz were the predominant species in Woopo Wetlands. Floods occurred twice, August and September in 2004. After the flooding events, species diversity decreased and species assemblage structures changed dramatically. Changes of the diversity and species assemblage structures were more evident in August then in September, because water level was much higher and inundation period was longer than September. A non-linear patterning algorithm of the Self-Organizing Map (SOM) was applied to discover the relationship between flooding events and carabid beetles community dynamics. Although abundance of the majority species decreased after the flooding events, that of the predominant species increased. Further detailed studies on species distribution and emigration patterns will likely bring a new insight in understanding of the adaptation mechanism of carabid beetles in wetlands.

구안괘사의 원인(原因)에 대(對)한 문헌적(文獻的) 고찰(考察) (Reference research for the cause of facial nerve paralysis)

  • 유한철;김한성
    • 혜화의학회지
    • /
    • 제9권1호
    • /
    • pp.243-258
    • /
    • 2000
  • From the reference research, the results obtained were as follows. 1. Until the "Song" dynasty, the predominant cause of facial nerve paralysis was the attack of Pathogenic Wind to "the Stomach Channel of Foot Yangming, (St.C.); and "the Small Intestine Channel of Hand Taiyang, (S.I.C.). They recognized the facial paralysis as an aspect of palsy. 2. In the period of Jin-Yuan(金元), the predominant cause was described as "Xuexu"(the deficiency of blood) and phlegm. They recognized that the facial palsy was a palsy. However, they also acceded to the possibility that there could be other explanations. 3. In the period of "Ming & Qing", there were numerous kinds of causes. For example, the following were identified as attacking the Meridian: the Pathogenic Cold; Pathogenic Heat; "Xinxu"(the deficiency in the heart); Fire and Heat combined as a pathogenic factor; "Pixu"(the deficiency in the spleen); and, "Xinxu"(the deficiency of blood). 4. In the past, Koreans have explained the facial paralysis according to the Chinese theories mentioned. However, recently there has been an emergence of another Chinese theory; whereby, facial paralysis is classified into causes and symptoms, and then medical treatment is applied accordingly. 5. From the occident medical perspective, the facial paralysis is categorized into two causes. The first is called central facial nerve paralysis and the second is called peripheral facial nerve paralysis. The latter is mainly caused by Bell's palsy, Herpez zoster oticus, and trauma.

  • PDF

시판 어패류의 정상세균군과 저장온도 및 저장기간이 정산세균군 변화에 미치는 영양 (Normal Flora and Effect of Storage Temperature and Period in the Commercial Fish and Shellfish)

  • 박석기;이용욱;정지연;김성원
    • 한국식품위생안전성학회지
    • /
    • 제12권1호
    • /
    • pp.20-25
    • /
    • 1997
  • In order to investigate bacterial sanitary condition of fish and shellfish, we examined the normal flora in the 25 species of commercial fish and shellfish, and also proportional change of normal flora by storage period and temperature. Isolated 334 wereisolated in the normal fish and shellfish and predominant genera were Pseudomonas (25.2%), Staphylococcus(10%), Acinetobacter (7.2%), Vibrio (6.9%), Micrococcus (5.4%), Aeromonas (5.2%), and Enterobacter (5.2%). In accordance with storage period and temperature, Pseudomonas grew on high ratio at 1$0^{\circ}C$ steadily, but Proteus had increased proportionally at 2$0^{\circ}C$ and 3$0^{\circ}C$. Additionally, Yeast, and Micrococcus had decreased by period.

  • PDF

비대칭 초기 조건을 갖는 얕은 아치의 동적 불안정과 순시 주파수 변화 (Dynamic Instability and Instantaneous Frequency of a Shallow Arch With Asymmetric Initial Conditions)

  • 손수덕;하준홍
    • 한국공간구조학회논문집
    • /
    • 제20권2호
    • /
    • pp.77-85
    • /
    • 2020
  • This paper examined the dynamic instability of a shallow arch according to the response characteristics when nearing critical loads. The frequency changing feathers of the time-domain increasing the loads are analyzed using Fast Fourier Transformation (FFT), while the response signal around the critical loads are analyzed using Hilbert-Huang Transformation (HHT). This study reveals that the models with an arch shape of h = 3 or higher exhibit buckling, which is very sensitive to the asymmetric initial conditions. Also, the critical buckling load increases as the shape increases, with its feather varying depending on the asymmetric initial conditions. Decomposition results show the decrease in predominant frequency before the threshold as the load increases, and the predominant period doubles at the critical level. In the vicinity of the critical level, sections rapidly manifest the displacement increase, with the changes in Instantaneous Frequency (IF) and Instant Energy (IE) becoming apparent.

서울시 산성비의 원인물질에 관한 연구 (Investigation on Source Strength to Acid Rain in the Seoul Area)

  • 신응배;이상권;안규홍
    • 한국대기환경학회지
    • /
    • 제2권2호
    • /
    • pp.66-74
    • /
    • 1986
  • Rain samples were collected at 10 sites in the Seoul area during the period of August through November, 1985. THe concentrations of the major cations $(H^+, Ca^{++}, MG^{++}, Na^+, K^+, NH_4^+)$ and the major anions $(SO_4^=, NO_3^-, Cl^-)$ were measured to characterize the main sources of chemical ions in rainwater. Correlating concentrations of ions to pH, calculated coefficients ranged from 0.1485 to 0/4296. Sulfate shows the largest coefficient indicating that sulfate is more closely associated with hydrogen ion than other ions. This may suggest that sulfuric acid contributes more to the acidity of rainwater in Seoul. It appears that the major chemicals measured in rainwater are from the anthropogenic sources of air pollution. Predominant chemicals are acidic at the Guro-, the Sinseol-, the Yangnam-, and the Ssangmun-dong with sulfate being the most predominant. IT also indicates that alkaline substances resulting from soil and dust have a significant effect on pH values of rainwater by neutralizing actions. According to Granat-model analysis, it is estimated that the relative contributions to the rainwater acidity in Seoul are 84% from sulfuric acid, 8% from nitric acid and 8% from hydrochloric acid.

  • PDF

국내 털진드기(Acarina: Trombiculidae)의 계절적 소장 및 지리적 분포 조사 (Seasonal Prevalence and Geographical Distribution of Trombiculid Mites(Acarina: Trombiculidae) in Korea)

  • 이인용;이한일;홍한기
    • 한국동물학회지
    • /
    • 제36권3호
    • /
    • pp.408-415
    • /
    • 1993
  • 털진드기 개체군에 대한 지리적 분포상과 계절적 소장에 관한 조사를 1990년 8월부터 1991년 12월까지 실시하여 다음과 같은 결과를 얻었다. Sherman trap을 사용하여 포획한 325마리의 들쥐들로부터 총 15,679개체의 털진드기를 채집하여 4속 12종을 동정하였는데, 쭈쭈가무시병의 매개종인 Leptotrombidium pallidum이 4,751개체로 전체의 30.3%를 차지하여 우점종이었고, 제2의 매개종으로 알려진 L. scutellare는 1,132개체로 전체의 7.2%을 차지하였다. 털진드기 개체군의 지리적 분포상이 종에 따라 심한 차이를 보이며 각 조사 지역마다 우점종이 다르게 나타났는데, 경기도 고양군 도래 5리에서는 L. pallidum, 포천군 산정리에서는 Neotrombicula kwangneungensis, 파주군 장곡리에서는 N. tamiyai, 전북 익산군 장신리에서는 L. orientale, 이리시 신용동에서는 L. scutellare 등이었다. 털진드기 개체군의 계절적 소장을 보면, L. pallidum은 2개의 정점을 보였는데 10-11월에 큰 정점을, 4-5월에 작은 정점을 보인 후 여름에는 거의 자취를 감추었고 L. scutellare는 10월에만 집중적으로 나타났다.

  • PDF

단주기 불규칙파에 의한 금진항 정온도 개선대책 연구 (Research on improvement measures of Harbor tranquility in Geumjin Fishing Port Excited by Incident Short Random Waves)

  • 장성열;문용호;박원경
    • 한국연안방재학회지
    • /
    • 제4권1호
    • /
    • pp.1-6
    • /
    • 2017
  • Most of the short period waves are blocked by the breakwaters when the short period irregular waves propagate into the ports. However, nonlinear irregular wave numerical experiments show that the long waves generated by the nonlinear interaction is predominant in the port. Seiches phenomenon in Geumjin Fishing Port is very similar to 60 and 300 second harbor oscillations. By arranging the inner breakwater of the proper length in the inside of the port, it is possible to effectively reduce seiches, as well as the short-period wave, and significantly improve the harbor tranquility. In the case of rectangular basin type such as the Geumjin Fishing Port, the multi-directional irregular wave numerical model should be used for the investigation and countermeasures for the harbor tranquility.

2011-2012년 서해 보령연안 수온의 시공간적 변동 (Temporal and Spatial Variations in Sea Surface Temperature Around Boryeong off the West Coast of Korea From 2011-2012)

  • 추효상;윤은찬
    • 해양환경안전학회지
    • /
    • 제23권5호
    • /
    • pp.497-512
    • /
    • 2017
  • 2011~2012년 보령연안 수온의 시공간적 변동특성을 장기 연속수온관측 자료를 이용하여 분석하였다. 수온은 반일 또는 일일의 단주기 변동이 전 계절에 탁월하고 그 진폭은 하계와 춘계에 크고 추계에 작다. 수온과 기온의 연변동 진폭은 기온 $12.9^{\circ}C$, 수온 $10.9^{\circ}C$로 기온이 더 크며, 연변동 최고위상은 기온 8월 2일, 수온 8월 22일로 기온이 20일 앞선다. 수온의 연변동 진폭은 원산도와 대천항 연안에서 가장 크다. 수온변동 중 일일주기는 대천항과 무창포항, 반일주기는 원산도 주변 협수로에서 탁월하며, 대천천 하구는 천해조 비율이 높다. 표층수온과 기온은 대체로 풍향 변동에 따라 변동한다. 하천수가 방출되면 수온은 상승 후 하강 또는 하강 후 상승한다. 수온 탁월주기는 0.5일, 1.0일, 15일 주기와 7~10일 전후이다. 수온변동특성에 따라 해역을 분류하면 (1)원산도 남동연안의 혼합수역 (2)삽시도~용도, 장고도~삽시도, 장고도~안면도 남쪽의 서쪽 외해수역 (3)용도~독산의 남쪽 외해수역 (4)송도~대천항~무창포항의 조간대 연안수역으로 구분된다.

한국내 집먼지진드기의 지역분포상 (Fauna and geographical distribution of house dust mites in Korea)

  • 이한일;전성후
    • Parasites, Hosts and Diseases
    • /
    • 제35권1호
    • /
    • pp.9-17
    • /
    • 1997
  • 1993-1994년에 걸쳐 전국 10개 지역내 주택에서 수거한 집먼지내의 진드기류를 조사하였다. 집 먼지는 평소 가정주부가 사용하는 전기진공청소기내 횔터에 모아진 집먼지 중 10 g을 채취하여 wet sieving metrod 일부 보완하여 진드기류를 분리하였다 채집된 총 7,257개체의 진드기를 동정한 결과 4아목 18과 23속 23종을 확인하였는데 그 중 Rhyzoglyphus robini, Sancossania phwllophcgianus, Cheyletus trouessarti 및 Scheloribotes lotipes의 4종은 국내 미기록 종이었다 전국적으로 가장 널리 분포되어 있고 서식밀도가 높은 종은 nemntophago릴os Jnrinae(DF)로 전체의 65.3%였고 D. Pteronvssinus(DP)가 20.6% Twrophnsus putrescentiqe(TP)가 6.5%를 차지하였는데, 이들 3종이 함께 서식하는 가정은 62개 조사대상 중 24.6%였고. 2개종이 공존하는 가정은 48 1%. 한종만 서식하는 가정은 27.3%였다. DF가 우점 종인 가정은 59개 조사 가정 중 63.5% DP가 우점종인 가정은 29.6%였고 TP가 우점종인 가정은 6.9%였다. 지역적으로는 서울. 광주 인천 전주 정주 등지에서는 DF가 우세하였으나 영광 춘천. 부산 영도 등 대기습도가 비교적 높은(> 73% RH) 지역에서는 DP가 우세한 것으로 나타났다. 집먼지진드기의 서식밀도를 보면 집먼지 10g 중 1.000개체 이상인 가정이 2.9%. 500-999 개체의 가정이 4.3%. 100-499개체의 가정이 15.7%였고 99개체 이하의 밀도를 보인 가정이 70.0%를 차지하였으며 전혀 채집되지 않은 가정은 7.1%였다. 아파트와 단독주택. 건물면적 청소횟수. 가족수. 건축년수 등과 집먼지진드기 서식밀도간에는 상관관계를 보이지 않았다.

  • PDF

Seasonal Variation of Phytoplankton and Zooplankton Communities in the Coastal Waters off Tongyeong in Korea

  • Lee, Jin-Hwan;Chae, Jin-Ho;Kim, Won-Rok;Jung, Seung-Won;Kim, Jong-Man
    • Ocean and Polar Research
    • /
    • 제23권3호
    • /
    • pp.245-253
    • /
    • 2001
  • To investigate the community structures and the their seasonal variation of phytoplankton and zooplankton, a study was conducted at 6 selected stations during the period from April 1999 to October 2000 in the marine ranching ground off Tongyeong. One hundred ninety species of phytoplankton were identified, including 146 diatoms, 38 dinoflagellates, 4 silicoflagellates and 2 euglenophytes. Phytoplankton standing crops varied extensively by months and stations, ranging from $3.0{\times}10^4\;cells/l\;to\;1.0{\times}10^6\;cells/l.$. The dominant species varied from the vertical distribution as well as seasonal changes. In April and July 1999, Skeletonema costatum and Ceratium fusus were predominant in both the surface and the bottom water columns. Leptocylindrus danicus was the dominant species in April and June 2000, and Thalassiosira spp. were also predominant in bottom waters in June 2000. Pseudonitzschia pungens and Chaetoceros spp. were the dominant species at both surface and near bottom waters in August and October 2000, respectively. Zooplankton abundance was comparatively high in April and July in 1999, and April, June, and October in 2000, but extremely low in November 1999. The density of dominant zooplankton was higher in 2000 than in 1999. Copepods were the most predominant group except for July 1999 when the bivalve larvae showed extremely high abundance. Acartia omorii and Oithona similis were the dominant or subdominant copepod species mainly in April 2000, and June/July, while O. davisae and O. plumifera had peaks in August and October 2000. Corycaeus affinis and Paracalanus sp. also showed higher peaks in April and June (or July), even though they occurred in all sampling time. Centropages abdominalis occurred abundantly only in April 1999. Oikopleura dioica, a gelatinous zooplankton, was another important zooplankton, showing high density in all samples except in July 1999.

  • PDF