• Title/Summary/Keyword: Predominant Period

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

  • Do, Yun-O;Jang, Min-Ho;Kim, Dong-Kyun;Joo, Gea-Jae
    • Korean Journal of Ecology and Environment
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    • v.40 no.2
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    • pp.346-351
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    • 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.

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

  • Yu, Han Chol;Kim, Han Sung
    • Journal of Haehwa Medicine
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    • v.9 no.1
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    • pp.243-258
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    • 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.

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

  • 박석기;이용욱;정지연;김성원
    • Journal of Food Hygiene and Safety
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    • v.12 no.1
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    • pp.20-25
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    • 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.

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

  • Shon, Sudeok;Ha, Junhong
    • Journal of Korean Association for Spatial Structures
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    • v.20 no.2
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    • pp.77-85
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    • 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.

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

  • 신응배;이상권;안규홍
    • Journal of Korean Society for Atmospheric Environment
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    • v.2 no.2
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    • pp.66-74
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    • 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.

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

  • 이인용;이한일;홍한기
    • The Korean Journal of Zoology
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    • v.36 no.3
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    • pp.408-415
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    • 1993
  • Studies on seasonal prevalence and geographical distribution of chigger mites were carried out during the period of August 1990-December 1991, and the results are summarized as follows. From total 325 field rodents collected during the study period, 15,679 chiggers were obtained and 12 species of 4 genera were identified. Leptotrombidium pallidum, a vector species of tsutsugamushi disease in Korea was the predominant species and distributed throughout the country except southern part of Korea, whereas L. scutellare, known also as a vector species was distributed mainly in southern part of Korea. The distribution of chigger mites was strongly localized by species, showing different predominant species at each locality during the same season. The predominant species were L. pallidum(92.3%) at Dorai-5ri, Wondang-ub, Neotrombicula kwangneungensis (44.7%) at Sanjung-ri, Pochun-gun, N. tamiyai (55.1%) at Changgok-ri, Paju-gun, L. orientale (55.2%) at Jangsin-ri, Iksan-gun, and L. scutellare (47.6%) at Sinyong-dong, Iri-si. Study on seasonal prevalence of L. pallidum chiggers resulted that they started appearing in September, showed the peak in November, almost disappeared during the period of December-March, reappeared in April-May showing a small peak, and again almost disappeared until September. L. scutellare showed the peak in October, sharply decreased thereafter, and disappeared during the period of January-September.

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

  • Chang, Sung-Yeol;Moon, Yong-Ho;Park, Won-Kyung
    • Journal of Coastal Disaster Prevention
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    • v.4 no.1
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    • pp.1-6
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    • 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.

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

  • Choo, Hyo-Sang;Yoon, Eun-Chan
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.23 no.5
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    • pp.497-512
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    • 2017
  • Temporal and spatial variations in surface water temperature were studied using data from temperature monitoring buoys deployed at 47 stations around Boryeong from 2011-2012 off the west coast of Korea. Temperature fluctuations are predominant at diurnal and semidiurnal periods for all seasons, and their amplitudes are large in spring and summer but small in autumn. The maximum annual change in air temperature takes place on August 2nd and August 22th for water temperature, which means the phase for air temperature precedes water temperature by 20 days. The diurnal period of water temperature fluctuation is predominant around Daecheon and Muchangpo Harbors, with the semidiurnal period around Wonsan Island, and the shallow water constituent period on the estuary around Daecheon River. On the whole, air and water temperatures fluctuate with wind. Spectral analyses of temperature records show significant peaks at the 0.5, 1 and 15 day marks with 7-10 day periods of predominant fluctuations. Cross-correlation analyses for the temperature fluctuation show that the waters around Boryeong can be classified into four areas: a mixed water zone around the southeast side of Wonsan Island, an off-shore area to the west, an off-shore area to the south and a coastal area along the shore from Song Island to Muchangpo Harbor.

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

  • 이한일;전성후
    • Parasites, Hosts and Diseases
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    • v.35 no.1
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    • pp.9-17
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    • 1997
  • During the period of 1933-1994, house dusts were collected from 65 homes at 10 different localities by operating electric vacuum cleaners. House dust mites were isolated from 10 g dust by applying the modified wet sieving method. Total 7,257 mites were collected and 23 species were identified. Among them, Demctophqgoines loyinaf (DF) was predominant (65. Soy) of the total) , followed by D. pteronvssinus (DP) (20.6%) and Tyrophagus nutrescentios (TP) (6.5%) . Rhizoglvphur robini, Sancqsscnin phvIlophogiann, Cheyletus trcussarti and Scheloribates latipes were the first findings from Korea. DF was predominant in Seoul (66.8%), Kwangju (63.6%), inland of Pusan (79.6%1, Inchon (96.5%), Taejon (83.9%), Chouju (87.15) and Chongiu (95.2%), whereas DP was predominant in Yongkwang-ub (72.5%) and Yongdo (island) of Pusan (64.9%), and TP in Chunchon (38.2%) The localities where DP and TP were predominant showed higher relative humidity in air (> 73% RH) . Among 62 study homes, DF, DP and TP were found in 24.6% of the homes, co-habitat of two species in 48.1% and one species in 27.3%. DF was predominant in 63.5% of the homes studied, DP in 29.6% and TP in 6.9%. In 10 g of the house dust, less than 99 mites were found in 49 homes (70.0%), 100-499 mites in 11 homes (15.7%), 500-999 mites in 3 homes (4.3%) and more than 1,000 mites in 2 homes (2.9%). No mite was found in 5 homes (7.1%). In order to evaluate environmental factors affecting the population density of house dust mites, house type, age of house construction, size of the house, number of the family and frequency of the cleaning were compared with the number of mites, and none of the above factors were statistically correlated with the mite density.

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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
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    • v.23 no.3
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    • pp.245-253
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    • 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.

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