• 제목/요약/키워드: Spring and Autumn Period

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채송화(Portulaca grandiflora Hook)의 계절에 따른 동종이형현상과 돌나무과형 유기산대사에 관한 연구 (Characteristics of CAM and Seasonal Dimorphism in the Succulent $C_4$ Dicot, Portulaca grandiflora Hook.)

  • Chang, Nam Kee;Chang Duck Jin
    • 환경위생공학
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    • 제5권2호
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    • pp.89-99
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    • 1990
  • Morphology, anatomy and diurnal acid fluctuations were investigated monthly for the succulent C4 dicot Portulaca grandiflora Hook. growing under natural environmental conditions. Modified Kranz-Type sturcture and typical CAM-like cells were shown in leaves and stems, respectively. Values of indices of mesophyll succulence inleaves stems were 5.62 and 16.68, respectively. The number of stomata were 1476$\textrm{cm}^{-2}$ in leaves while the stomata in stems were not observed through growing seasons from spring to summer. However, on Sep. 16, 1981 in defoliate autumn season, stomata were begun to be produced for the first time in stems and the number were increased gradually to 216$\textrm{cm}^{-2}$ on Oct. 29. This feature can be interpreted as a seasonal plant dimorphism. P. grandiflora exhibited a diurnal fluctuation of titratable acidity in leaves and stems. Seasonal amplitudes of acid fluctuation in stems were as follows: 27 $\mu$eq./g.f.wt. on Sep. 21; 57$\mu$eq/g.f.wt. on Oct. 3; 80$\mu$eq./g.f.wt. on Oct. 21. Such the results in seasonal amplitude were able to consider due to decrease of light period and cool night air temperature according to change of season. Also, the naturally defoliated stems which had already stomata exhibited usual diurnal acid fluctuation, on the other hand the treated stems which possessed artificially closed stomata showed a few of acid fluctuation. Especially, stomata in stems are developed by seasonal dimorphism and activated stomata participate in CAM behavior of stems.

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방조제 건설 중인 2001-2002년 새만금 하구역 어류 종조성의 계절 변동 (Seasonal Variation in Species Composition of Fish in the Estuary of Saemangeum Waters during the Construction of a Dike in 2001-2002)

  • 이태원;문형태;김광천
    • 한국수산과학회지
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    • 제36권3호
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    • pp.298-305
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    • 2003
  • Seasonal variation in species composition of fish in the estuary of Saemangeum water in the western coast of Korea was determined using seasonal samples collected by an otter trawl from April 2001 to February 2002. Species compositions did not differ significantly among the 4 stations (p>0.05, Wilcoxon signed-rank test). The cumulative number of species and species diversity (H') approached asymptote after four 30-min trawl hauls. Therefore 30-min trawl samples from each of the four stations were pooled to represent each season. A total of 45 species 2758 individuals and 30,346.8 g of fish were collected during the study period. Of the fish collected Leiognathus nuchalis, Synechogobius hasta, Neosalanx jordani, Konosirus punctatus and Chaeturichthys stigmatias predominated in abundance accounting for $68\%$ of the total number of individuals. Seasonal variation of fish abundance showed a similar trend to those of the other western coastal waters of Korea. The resident species were collected only in spring and autumn. Number of species and biomass were highest in summer due to the catch of many migrating species. In winter catch amount was low, and only 7 species were collected.. Brackish water fishes were more abundant in the study area, and Johnius grypotus and Cynoglossus joyneri were not premominated compared to the other coastal waters. This difference in species compositions may be related to the lower salinity in this estuarine habitat than in the other western coastal waters of Korea.

여자만 새꼬막, Scapharca subcrenata (Bivalvia: Arcidae)의 생리적변화 및 계절별 에너지수지 (Variation in physiological energetics of blood cockle Scapharca subcrenata (Bivalvia: Arcidae) from Yeoja bay, South coast of Korea)

  • 신윤경;이원찬;김성연;전제천;김응오
    • 한국패류학회지
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    • 제27권3호
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    • pp.205-211
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    • 2011
  • This study presents physiological rates of oxygen consumption, ammonia excretion, feeding rates, O/N ratio and assimilation efficiency of the blood cockle, Scapharca subcrenata, determined from specimens collected in Yeoja bay on the south coast of Korea. Physiological parameters were measured monthly under static, laboratory controlled conditions with ambient conditions, and measurements were performed seasonally in order to estimate scope for growth and its probable sources of variation. Oxygen consumption and ammonia excretion rates have been increased as temperature increased with the highest value of August, 2008. Feeding rate was the highest during April whereas the lowest was during August which is a period of gametogenesis with minimum biomass of phytoplankton around sampling area. Assimilation efficiency was not significantly different seasonally and O/N ratio decreased during July to August. The scope for growth was negative during high temperature months(July to August), reflecting the high temperature and low feeding rate, and had its highest positive values during spring and autumn. Data on the physiological parameters and scope for growth of Scapharca subcrenata obtained in this study will be used to assess the carrying capacity for blood cockle cultivation.

주요 채소에서 발생하는 진딧물의 종류와 발생소장에 관한 연구 (Colonizing Aphid Species and Their Seasonal Fluctuations in Some Vegetable Crops)

  • 김석환;김인수;이문홍
    • 한국응용곤충학회지
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    • 제25권3호
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    • pp.129-132
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    • 1986
  • 무우, 배추, 고추, 오이에 기생하는 진딧물의 종류와 주요종의 발생소장을 $1982{\sim}1984$의 3개년간 살충제 무살포 조건에서 조사한 결과는 다음과 같다. 1. 무우와 배추의 기생진딧물은 복숭아혹진딧물, 무우테두리진딧물, 싸리수염진딧물, 목화진 디물의 4종으로 주요종은 복숭아혹진딧물과 무우테두리진딧물 2종이었다. 2. 고추의 기생진딧물은 복숭아혹진딧물, 목화진딧물, 싸리수염진딧물의 3종으로, 복숭아혹진 딧물과 목화진딧물 2종이 주요종이었고, 오이에서는목화진딧물, 싸리수염진딧물, 복숭아혹진딧물이 기생하나 목화진딧물 1종이 우점종이었다. 3. 순별강우량이 200mm 이상일 때, 진딧물의 밀도는 급격한 감소를 보였다. 4. 무우와 배추의 복숭아혹진딧물과 무우테두리진딧물, 고추의 복숭아혹진딧물과 목화진딧물은 두 종간의 상대밀도에 있어서 봄에 다발생한 종은 가을에 소발생하였다.

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군산 연안 해역 항행 위해 요소 분석 (1) (Analysis on the navigation risk factors in Gunsan coastal area (1))

  • 정초영;유상록
    • 수산해양기술연구
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    • 제53권3호
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    • pp.286-292
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    • 2017
  • The Coastal VTS will be continuously constructed to prevent marine traffic accidents in the coastal waters of the Republic of Korea. In order to provide the best traffic information service to the ship operator, it is important to understand the navigation risk factor. In this study, we analyzed the navigational hazards of Gunsan coastal area where the coastal VTS will be constructed until 2020. For this purpose, major traffic flows of merchant ships and density of vessels engaged in fishing were analyzed. This study was conducted by Automatic Identification System (AIS) and Vessel Pass (V-PASS) data. The grid intervals are 10 minute ${\times}$ 10 minute (latitude ${\times}$ longitude) based on the section of the sea. A total of 30 sections were analyzed by constructing a grid. As a result of the analysis, the major traffic flows of the merchant vessels in the coastal area of Gunsan were surveyed from north to south toward Incheon, Pyeongtaek, Daesan, Yeosu, Pusan and Ulsan, and from east to west in the port of Gunsan Port, 173-3, 173-6, 173-8, 183-2, 183-5, 183-8, 183-3, 184-1 and 184-2. As a result of the study, the fishing boats in Gunsan coastal area mainly operated in spring and autumn. On the other hand, the main traffic flow of merchant ships and the distribution of fishing vessels continue to overlap from March to June, so special attention should be paid to the control during this period.

권역별 주택금융부채 실태 (Home Financing and its Debt Load of Home-owning Households in korea)

  • 한지영;이현정
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2011년도 춘계학술발표대회 논문집
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    • pp.296-300
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    • 2011
  • It's well known that housing is one of the largest holdings in household wealth and at the same time the majority of households highly concentrate on it for their wealth accumulation. Coupled with a low interest rate and increasing housing price, the rationale is conspicuous and the propensity to debt-financed consumption becomes strengthened. This research was to examine the risk of home financing. In doing so, the study utilized several secondary data to identify the characteristics of households who finance loans for home buying in three regions of the nation - so-called Bubble 7, Seoul Metropolitan Area, and others. Based on the 2009 KB survey, the major findings were as follows: the majority of the studied households in Seoul Metropolitan Area who owned a house lived in rental housing, housing accounted for 89% of the household wealth, and home loans taken on were a ballon payment amortized for a short-term period (5 years) with an adjustable interest rate. In addition, the payment method most of the households depend on is income. The financing mechanism fueled debt load of the households, and further they are financially very vulnerable to such factors as increase in interest rate, unemployment and market downturn. In the absence of understanding the financial system, the consumption behavior leads to house-poor, so that financial accountability and ethics are addressed while the intervention of the government in home financing system should be more cautious but stimulate financial soundness in household wealth accumulation.

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도시가로 보행자공간의 활성화 측면에서 바라본 청계천 이용자의 만족도 조사연구 (The Survey Study on ChungGyeCheon users's Satisfaction in Terms of the Utilization Aspects of the Pedestrian Space of the City Street)

  • 곽승미;강부성
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2009년 춘계학술발표대회 논문집
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    • pp.327-331
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    • 2009
  • Covering structures and elevated road of Cheonggyecheon are the by-products of the developing era when functionality and efficiency were emphasized. Historic river restoration project around Cheonggyecheon which had been emerged as a threat to the safety of the citizens due to its corrosion and structural defects as time passes had been performed during the period from July, 2003 through October, 2005 under the slogan of future-oriented urban environment creation. By dint of this river restoration project, its value is being heightened as almost all the rivers of Seoul including Seongbukcheon, Chungreungcheon and Honghaecheon have been arranged by inter-active linkage. In addition, this river is becoming a place frequented by the numerous visitors at home and aborad by providing the citizens with an attractive space for utilizing leisure time. Currently in the diversified areas, an academic research on the Cheonggyecheon restoration is under progress. In this study, sampled questionnaire for the visitors was carried out by site visit with the necessity of users' satisfaction survey in terms of revitalization of pedestrian space of the city street. As a result of this, natural restoration and provision of leisure space were surveyed to be highly assessed in terms of satisfaction and insufficient provision of convenience facilities including toilet and parking space was pointed out as a matter to be improved. As Cheonggyecheon is invigorated from the obstacle of urban environment through its epochal restoration, its value provided to us will be evaluated and by supplementing the deduced problems, we intend to find its meaning in our hope that this would become a sustainable future assets providing a basic data.

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황해 영광 안마 군도 해역의 요각류 출현 양상에 영향을 미치는 계절적 환경 요인 (The Seasonal Environmental Factors Affecting Copepod Community in the Anma Islands of Yeonggwang, Yellow Sea)

  • 정영석;이석주;추서휘;윤양호;조현서;김대진;서호영
    • Ocean and Polar Research
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    • 제45권2호
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    • pp.43-55
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    • 2023
  • This study was conducted to understand the seasonal patterns and variation of the copepod community in the Anma Islands of Yeonggwang, Yellow Sea, with a focus on seasonal surveys to assess the factors affecting their occurrence. Throughout the survey period, Acartia hongi, Paracalanus parvus s. l., and Ditrichocorycaeus affinis were dominant species, while Acartia ohtsukai, Acartia pacifica, Bestiolina coreana, Centropages abdominalis, Labidocera rotunda, Paracalanus sp., Tortanus derjugini, Tortanus forcipatus occurred differently by season and station. As a results of cluster analysis, the copepod communities were distinguished into three distinct groups: spring-winter, summer, and autumn. The results of this study showed that the occurrence patterns of copepod species can vary depending on environmental conditions (topographic, distance from the inshore, etc.), and their spatial occurrence patterns between seasons were controlled by water temperature and prey conditions. One of the physical mechanisms that can affect the distribution of zooplankton in the Yellow Sea is the behavior of the Yellow Sea Bottom Cold Water (YSBCW), which shows remarkable seasonal fluctuations. More detailed further studies are needed for clear grounds for mainly why to many Calanus sinicus in the central region of the Yellow Sea are seasonally moving to the inshore, what strategies to seasonally maintain the population, and support the possibilities of complex factors.

소아(小兒) 감모(感冒)에 대(對)한 임상적(臨床的) 고찰(考察) (The Clinical Study of Common Cold)

  • 이훈;정재환;이진용;김덕곤
    • 대한한방소아과학회지
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    • 제13권2호
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    • pp.125-137
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    • 1999
  • The common cold is the most common pediatric infectious disease, and the incidence is higher in early childhood than in any other period of life. Treatment of the common cold is largely symptomatic. Thus treatment of oriental medicine for the common cold is very effective and safe. We studied 81 children suffering from common cold Oriental Medicine Hospital in Kyunghee University, and analyzed age, sex, season, clinical manifestation, complications, prescription. The results were as follows: 1. Age and sex distribution of children from 1 to 3 was 37.1%, 3 to 6 was 34.6%, over 6 was 24.7%, male to female ratio was 1.31 : 1 2. Frequency of affection per year, from 3 to 5 was 30.9%, 6 to 9 was 29.6%, over 10 was 27.2%, below 3 was 4.9% 3. Frequency of seasons giving rising to common cold, winter was 40.7%, spring and autumn were 16%, summer was 1.2%. 4. Frequency of complications, empyema and rhinitis were 38.3%, asthma was 21%, pneumonia was 16%, atopic dermatitis was 7.4%. 5. Frequency of Clinical manifestation, cough and sputum were 45.7%, high fever and sore throat were 27.2%, complex symptom was 25.9%. 6. Frequency of prescription, BoAh-Tang-gami(補兒湯加味)was 27.2% BangPungHaeDoc-Tang(防風解毒湯)was 11.1 %, GamiGinHae-Tang (加味鎭咳湯)was 11.1%.

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西海 京畿 植物플랑크톤에 對한 생態學的 硏究 II. 光度, 透明度, 浮游物質 (The ecological study of phytoplankton in Kyeonggi Bay, Yellow Sea Il. Light intensity, Transparency, Suspended substances)

  • 최중기;심재형
    • 한국해양학회지
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    • 제21권2호
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    • pp.101-109
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    • 1986
  • 경기만 식물플랑크톤 생태에 영향을 미치는 광조건을 알기 위하여 광도, 보상 깊이, 소광계수, 투명도, 부유물질등이 조사 연구되었다. 봄부터 가을까지는 식물플 랑크톤성장에 적절한 광도를 유지하였으나 가을에는 플랑크톤 성장을 제한할 정도 의 낮은 광도를 보였다. 투명도 및 보상깊이도 계절적인 변화를 보여 동계에는 표 층하 1-2m내에 국한되었다. 소광계수는 만 전체에 전반적으로 높은 양상을 보이고 뚜렷한 계절변화를 보였다. 이와같은 낮은 광도, 낮은 보상깊이, 투명도, 높은 소광 계수는 경기만 내 특징인 높은 탁도와 높은 부유물질 농도에 기인된다. 특히 겨울 철의 나쁜 광조건은 조류와 북서계절풍에 의한 심한 수괴의 혼합으로 미세 퇴적물 의 재 부유 현상에 기인된 것으로 보인다.

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