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Characteristics of the Differences between Significant Wave Height at Ieodo Ocean Research Station and Satellite Altimeter-measured Data over a Decade (2004~2016) (이어도 해양과학기지 관측 파고와 인공위성 관측 유의파고 차이의 특성 연구 (2004~2016))

  • WOO, HYE-JIN;PARK, KYUNG-AE;BYUN, DO-SEONG;LEE, JOOYOUNG;LEE, EUNIL
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.23 no.1
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    • pp.1-19
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    • 2018
  • In order to compare significant wave height (SWH) data from multi-satellites (GFO, Jason-1, Envisat, Jason-2, Cryosat-2, SARAL) and SWH measurements from Ieodo Ocean Research Station (IORS), we constructed a 12 year matchup database between satellite and IORS measurements from December 2004 to May 2016. The satellite SWH showed a root mean square error (RMSE) of about 0.34 m and a positive bias of 0.17 m with respect to the IORS wave height. The satellite data and IORS wave height data did not show any specific seasonal variations or interannual variability, which confirmed the consistency of satellite data. The effect of the wind field on the difference of the SWH data between satellite and IORS was investigated. As a result, a similar result was observed in which a positive biases of about 0.17 m occurred on all satellites. In order to understand the effects of topography and the influence of the construction structures of IORS on the SWH differences, we investigated the directional dependency of differences of wave height, however, no statistically significant characteristics of the differences were revealed. As a result of analyzing the characteristics of the error as a function of the distance between the satellite and the IORS, the biases are almost constant about 0.14 m regardless of the distance. By contrast, the amplitude of the SWH differences, the maximum value minus the minimum value at a given distance range, was found to increase linearly as the distance was increased. On the other hand, as a result of the accuracy evaluation of the satellite SWH from the Donghae marine meteorological buoy of Korea Meteorological Administration, the satellite SWH presented a relatively small RMSE of about 0.27 m and no specific characteristics of bias such as the validation results at IORS. In this paper, we propose a conversion formula to correct the significant wave data of IORS with the satellite SWH data. In addition, this study emphasizes that the reliability of data should be prioritized to be extensively utilized and presents specific methods and strategies in order to upgrade the IORS as an international world-wide marine observation site.

Relationship between Limnological Characteristics and Algal Bloom in Lake-type and River-Type Reservoirs, Korea (호소형 및 하천형 댐 호의 육수학적 특성과 조류발생과의 상관관계)

  • Kim, Jong-Min;Heo, Seong-Nam;Noh, Hye-Ran;Yang, Hee-Jeong;Han, Myung-Soo
    • Korean Journal of Ecology and Environment
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    • v.36 no.2 s.103
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    • pp.124-138
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    • 2003
  • This paper aimed to analyze the relationship between alga3 bloom patterns and hydrological, limnological data which were collected from major reservoirs in Korea for 8 years (1990${\sim}$1997). Water temperature of river-type reservoirs showed wider seasonal fluctuations than that of lake-type. pH of lake-type reservoirs was low in winter season but high in summer season. In contrast, river-type reservoirs showed high pH in spring and autumn seasons as well, and very low in summer season. COD of lake-type reservoirs and Paldang reservoir was lower (2${\sim}$3 mg/L) than that of Geumgang and Nagdonggang reservoirs (6${\sim}$9 mg/L). Dissolved oxygen (DO) of river-type reservoirs was higher than that of lake-type reservoirs. Seasonal fluctuation pattern of DO saturation in river-type reservoirs was high (80 ${\sim}$100%) and remained relatively constant whereas lake-type reservoirs showed the highest level (93%) in late spring or early summer, which gradually decreased entering winter season(46${\sim}$06%). And monthly variation of DO saturation showed inverse proportion to water volume in lake-type reservoirs. Nutrients concentration in river-type lake is higher than lake-type. Seasonal fluctuation of nutrients (T-N, T-P) in lake-type reservoirs was relatively small than that of river-type reservoirs. Annual mean N/P mass ratio of lake-type reservoirs was higher than that of river-type. Transparency tended to related with the suspended solid concentration in river-type reservoirs. Algal bloom of lake-type and river-type reservoirs occurred at any time except rainfall and winter periods. And it dominated in summer and early autumn, respectively. Algal bloom of river-type reservoirs was higher than that of lake-type. Relationship between rainfall and chlorophyll- a in lake-type reservoirs was relatively high, however river-type reservoirs showed insignificant.

Fish Community Structure Analysis and Ecological Health Assessments in the Headwater Watershed of Nakdong River (낙동강 상류 수계의 어류 군집 구조 분석 및 생태건강도 평가)

  • Lee, Jae-Hoon;Hong, Young-Pyo;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.40 no.3
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    • pp.403-411
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    • 2007
  • The purpose of the study was to evaluate fish community, based on conventional at Shannon-Weaver diversity index (H'), and ecological health, based on the Index of Biological Integrity (IBI) using fish assemblage in the eight sites of Nakdong River during June${\sim}$August 1999. Total number of species sampled was 19 species, and two sensitive species of Zacco temminckii (51%) and Rhynchocypris oxycephalus (28%) dominated the fish community. Also, trophic guild analyses showed that insectivore was 87% of the total and omnivore was rare, indicating that the ecological health is well maintained in the system. The pattern of spatial variation in the diversity index(H') was very similar to patterns of the species number and individual number, whereas the pattern of H' was not matched with the tolerance and trophic guild data. The diversity index (H') showed highest (1.56) in Site 6 where the proportion of sensitive species and tolerant species was minimum and maximum, respectively, and where the insectivore and omnivore were minimum and maximum. In other words, the diversity index was not matched at all with the trophic and tolerant guilds, indicating that the conventional index did not reflect the ecological characteristics of fish community in the system. In the mean time, the ecological health (IBI) averaged 33.5 (n=8), indicating "good${\sim}$fair condition" and the IBI values matched with trophic and tolerance guilds. Maximum IBI occurred in Site 2 where the sensitive and msectivore species were nearly maximum, and the tolerant and omnivore species were almost minima, indicating that IBI values were closely associated with the ecological functions and health conditions. Overall data suggest that the conventional diversity index may not effective for a evaluation of fish community, and that in contrast the IBI approach may be a useful tool for diagnosis of stream community.

Evaluation of Ecological quality and establishment of ecological restoration guideline in landscape level of Mt. Moodeung National Park (무등산국립공원의 생태적 질 평가 및 복원 가이드라인 수립)

  • Lim, Chi Hong;Park, Yong Su;An, Ji Hong;Jung, Song Hie;Nam, Kyeong Bae;Lee, Chang Seok
    • Korean Journal of Ecology and Environment
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    • v.49 no.4
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    • pp.296-307
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    • 2016
  • Ecological restoration is an eco-technology, which heals the nature damaged by human activity by imitating organization and function of the integrate nature and thereby provide an inhabitable space for diverse organisms. Such an ecological restoration has to be carried out by applying restoration plan prepared based on the results of diagnostic evaluation discussed in the diversified respects. This study aims to prepare an ecological restoration plan of the damaged forest ecosystem in Mt. Moodeung National Park. To arrive at the goal, first of all, we diagnosed quality of forest landscape established in Mt. Moodeung National Park based on natural (topography, climate, and distribution of vegetation) and artificial (land use, linear landscape element) factors. In addition, we evaluated the integrity of each zone divided by linear landscape element quantitatively based on geometric property and land use intensity. As the result of analysis, topography of Mt. Moodeung National Park tended to be depended on weathering property of parent rock and vegetation zones were divided to three vegetation zones. Based on land use pattern, deciduous broad-leaved forest, evergreen needle-leaved forest, and mixed forest occupied about 90% of Mt. Moodeung National Park. Mean score of forest landscape quality was shown in $69.86{\pm}11.41$. As a result, forest landscape elements in Mt. Moodeung National Park were influenced greatly by human activity and the degree was depended on topographic condition. This study suggested the synthetic restoration plan to improve ecological quality of Mt. Moodeung National Park based on the results of diagnostic evaluation.

Evaluation on Heating Effects of Geothermal Heat Pump System in Farrowing House (지열 난방시스템을 이용한 분만돈사의 난방효과 분석)

  • Choi, H.C.;Park, Jae-Hong;Song, J.I.;Na, J.C.;Kim, M.J.;Bang, H.T.;Kang, H.G.;Park, S.B.;Chae, H.S.;Suh, O.S.;Yoo, Y.S.;Kim, T.W.
    • Journal of Animal Environmental Science
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    • v.16 no.3
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    • pp.205-215
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    • 2010
  • Geothermal heat pump system (GHPS) is an energy-efficient technology that use the relatively constant and renewable energy stored in the earth to provide heating and cooling. With the aim of using GHPS as a heating source, it's possibilities of application in farrowing house were examined by measuring environmental assessment and sow's performance. A total of 96 sows were assigned to 2 pig housings (GHPS and conventional housing) with 48 for four weeks in winter season. During the experimental period, indoor maximum temperature in GHPS-housing was measured up to $26.7^{\circ}C$, average temperature could maintain $21.2^{\circ}C$. The mean value of dust levels and $CO_2$, $NH_3$ and $H_2S$ gas emissions were decreased in GHPS-housing compare with those of conventional housing. Litter size, birth weight, parity and weaning weight did not differ between housings. However, feed intake of sow in GHPS-housing was lower than that of conventional housing. In energy consumption for heating, electric power consumption increased in GHPS-housing than the conventional housing, a 2,250 kwh increase, whereas there is no fuel usage for heater in GHPS-housing. Amount of ground water circulated for heating in cold weather for earth heat exchanger was 8.4-12.9 ton per day. In conclusion, GHPS may have environmental benefits and effectiveness of heating in farrowing housing and affect the performance in sows.

Comparative Analysis of GNSS Precipitable Water Vapor and Meteorological Factors (GNSS 가강수량과 기상인자의 상호 연관성 분석)

  • Jae Sup, Kim;Tae-Suk, Bae
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.4
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    • pp.317-324
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    • 2015
  • GNSS was firstly proposed for application in weather forecasting in the mid-1980s. It has continued to demonstrate the practical uses in GNSS meteorology, and other relevant researches are currently being conducted. Precipitable Water Vapor (PWV), calculated based on the GNSS signal delays due to the troposphere of the Earth, represents the amount of the water vapor in the atmosphere, and it is therefore widely used in the analysis of various weather phenomena such as monitoring of weather conditions and climate change detection. In this study we calculated the PWV through the meteorological information from an Automatic Weather Station (AWS) as well as GNSS data processing of a Continuously Operating Reference Station (CORS) in order to analyze the heavy snowfall of the Ulsan area in early 2014. Song’s model was adopted for the weighted mean temperature model (Tm), which is the most important parameter in the calculation of PWV. The study period is a total of 56 days (February 2013 and 2014). The average PWV of February 2014 was determined to be 11.29 mm, which is 11.34% lower than that of the heavy snowfall period. The average PWV of February 2013 was determined to be 10.34 mm, which is 8.41% lower than that of not the heavy snowfall period. In addition, certain meteorological factors obtained from AWS were compared as well, resulting in a very low correlation of 0.29 with the saturated vapor pressure calculated using the empirical formula of Magnus. The behavioral pattern of PWV has a tendency to change depending on the precipitation type, specifically, snow or rain. It was identified that the PWV showed a sudden increase and a subsequent rapid drop about 6.5 hours before precipitation. It can be concluded that the pattern analysis of GNSS PWV is an effective method to analyze the precursor phenomenon of precipitation.

A New Early-Heading, High-Yielding Triticale Cultivar for Forage, 'Shinseong' (숙기가 빠르고 종실 수량이 많은 트리티케일 신품종 '신성')

  • Han, Ouk-Kyu;Park, Hyung-Ho;Park, Tae-Il;Oh, Young-Jin;Song, Tae-Hwa;Kim, Dea-Wook;Chae, Hyun-Seok;Hong, Ki-Heung;Bae, Jeong-Suk;Kim, Ki-Soo;Yun, Geon-Sig;Lee, Seong-Tae;Ku, Ja-Hwan;Kweon, Soon-Jong;Ahn, Jong-Woong;Kim, Byung-Joo
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.36 no.2
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    • pp.142-149
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    • 2016
  • 'Shinseong', a winter forage triticale cultivar (X Triticosecale Wittmack), was developed at the Department of Rice and Winter Cereal Crop, NICS, RDA in 2015. The cultivar 'Shinseong' was selected from the cross RONDO/2$^*$ERIZO_11//KISSA_4/3/ASNO/ARDI_3//ERIZO_7 by CIMMYT (Mexico) in 1998. Subsequent generations were handled in pedigree selection programs at Mexico from 1999 to 2004, and a line 'CTSS98Y00019S-0MXI-B-3-3-5' was selected for earliness and good agronomic characteristics. After preliminary and advance yield testing in Korea for 3 years, the line was designated 'Iksan47'. The line was subsequently evaluated for earliness and forage yield in seven locations, Jeju, Iksan, Cheongwon, Yesan, Gangjin, Daegu, and Jinju from 2013 to 2015 and was finally named 'Shinseong'. Cultivar 'Shinseong' has the characteristics of light green leaves, yellow culm and spike, and a medium grain of brown color. The heading date of cultivar 'Shinseong' was April 24 which was 3 days earlier than that of check cultivar 'Shinyoung'. The tolerance or resistance to lodging, wet injury, powdery mildew, and leaf rust of 'Shinseong' were similar to those of the check cultivar. The average forage dry matter yield of cultivar 'Shinseong' at milk-ripe stages was $15MT\;ha^{-1}$, which was 3% lower than that ($15.5MT\;ha^{-1}$) of the check cultivar 'Shinyoung'. The silage quality of 'Shinseong' (6.7%) was higher than that of the check cultivar 'Shinyoung' (5.9%) in crude protein content, while was similar to the check cultivar 'Shinyoung' in acid detergent fiber (34.6%), neutral detergent fiber (58.6%), and total digestible nutrients (61.6%). It showed grain yield of $7.2MT\;ha^{-1}$ which was 25% higher than that of the check cultivar 'Shinyoung' ($5.8MT\;ha^{-1}$). This cultivar is recommended for fall sowing forage crops in areas in which average daily minimum mean temperatures in January are higher than $-10^{\circ}C$.

A New High-yielding Winter Oat Cultivar for Whole Crop Forage, 'Dahan' (내한 다수성 추파 조사료용 총체 귀리 신품종 '다한')

  • Han, Ouk-Kyu;Park, Tae-Il;Park, Hyung-Ho;Song, Tae-Hwa;Kim, Kee-Jong;Park, Nam-Geon;Ju, Jung-Il;Jang, Young-Jik;Hwang, Jong-Jin;Kwon, Young-Up
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.34 no.1
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    • pp.26-32
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    • 2014
  • 'Dahan' (Avena sativa L.), a winter oat cultivar for forage use, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute Crop Science (NICS), Rural Development Administration (RDA) in 2011. It was derived from an original cross between $F_1$[Sprinter/73625] and 'Gwiri26'. Subsequent generations followed by the cross were handled in bulk and pedigree selection programs at Suwon. A line, 'SO99027-GB-B-113-4-4-3', was selected for cold tolerance and good agronomic characteristics and as a line name of 'Gwiri75'. The line 'Gwiri75' was subsequently evaluated for cold tolerance and forage yield during 3 years in four region such as Yesan, Iksan, Kimjae, and Jeju, from 2009 to 2011 and finally named as 'Dahan'. Though similar in heading date to the check cultivar Samhan, 'Dahan' had tall plant length and lodging resistance. It's average forage dry matter yield harvested at milk-ripe stage was 15.6 ton $ha^{-1}$, compared with 14.1 ton $ha^{-1}$ of check cultivar. Cultivar 'Dahan' was lower to the check cultivar 'Samhan' in protein content (8.4% and 9.9%, respectively), while it was superior to the check cultivar in total digestible nutrients (TDN) (60.8% and 59.3%, respectively), and in TDN yield $ha^{-1}$ (9.5 ton and 8.4 ton, respectively). Fall sowing of 'Dahan' is recommended only in the areas where daily minimum mean temperatures are averaged higher than $-7^{\circ}C$ in January, and excluded in mountain area where frost damage is presumable.

A New Forage Oat Cultivar 'Taehan' for Early-heading and High-yielding of Double Cropping Cultivation in Paddy Field (이모작 재배에 적합한 조숙성 추파용 귀리 신품종 '태한')

  • Han, Ouk-Kyu;Park, Tae-Il;Park, Hyung-Ho;Song, Tae-Hwa;Oh, Young-Jin;Hwang, Jong-Jin;Kwon, Young-Up
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.33 no.4
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    • pp.227-233
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    • 2013
  • 'Taehan' (Avena sativa L.), a winter oat for forage use, was developed by the breeding team at the Department of Rice and Winter Cereal Crops, NICS, RDA in 2012. It was derived from a cross between 'Malgwiri' and 'CI8015'. Subsequent generations were handled in bulk and pedigree selection programs at Suwon and Yeoncheon, respectively. After 2 years of preliminary and advanced yield tests, 'SO00020B-YB-15-5-9-4-3', designated as 'Gwiri78', were subsequently evaluated for earliness and forage yield during 3 years in four regions such as Yesan, Iksan-1 (Paddy), Iksan-2 (upland), and Jeju from 2010 to 2012, and finally named 'Taehan'. Over 3 years, the heading date of 'Taehan' was about 6 days earlier than that of the check cultivar 'Samhan' (May 8 and May 14, respectively), and their average forage dry matter yield harvested at the milk-ripe stage was 14.5 tone $ha^{-1}$, compared with 14.1 tone $ha^{-1}$ for the check cultivar. The cultivar 'Taehan' was lower than that of the check cultivar 'Samhan' in terms of protein content (6.3% and 7.7%, respectively) and total digestible nutrients (60.7%, and 62.1%, respectively). The TDN yield was more than that of the check cultivar (9.1 tone $ha^{-1}$ and 8.0 tone $ha^{-1}$, respectively). Fall cropping of 'Taehan' is recommended only in areas where average daily minimum mean temperatures in January are > $-6^{\circ}C$, and it should not be cultivated in mountainous areas, where frost damage is likely to occur.

Improvement of an Simultaneous Determination for Clenbuterol and Ractopamine in Livestock Products using LC-MS/MS (LC-MS/MS를 이용한 축산물 중 clenbuterol과 ractopamine의 동시 분석법 개선)

  • Cho, Yoon-Jae;Chae, Young-Sik;Kim, Jae-Young;Kim, Hyung-Soo;Kang, Ilhyun;Do, Jung-Ah;Oh, Jae-Ho;Kwon, Kisung;Chang, Moon-Ik
    • Korean Journal of Food Science and Technology
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    • v.45 no.1
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    • pp.25-33
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    • 2013
  • Clenbuterol and ractopamine, which are ${\beta}$-agonists, have been misused as a growth promoting agent in meat producing animals. Clenbuterol was banned for veterinary drug in Korea because of its problems regarding safety. Due to their adverse effects, such as cardiovascular and central nervous diseases on human health proper control and monitoring should be conducted. The existing analytical method of clenbuterol and ractopamine in the Food code was improved through our present study. The bovine muscle samples were subjected to enzymatic hydrolysis, extracted with ethyl acetate and defatted by hexane-methanol partitioning. A molecular imprinted polymer (MIP) solid phase extraction cartridge was used for clean-up and LC-MS/MS was operated in positive multiple reaction monitoring (MRM). Clenbuterol-$d_9$ and ractopamine-$d_3$ were used as an internal standard. The renewed method was validated according to the CODEX guideline. The limits of quantitation for clenbuterol and ractopamine were 0.2 and 0.5 ${\mu}g/kg$, respectively. The mean recoveries ranged in 104.2-113.5% for clenbuterol and in 107.6-118.1% for ractopamine. The improved method was able to save both time and expenses.