• Title/Summary/Keyword: observatory

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Comparison of Sea Level Data from TOPEX/POSEIDON Altimeter and in-situ Tide Gauges in the East Asian Marginal Seas (동아시아 주변해역에서의 TOPEX/POSEIDON 고도 자료와 현장 해수면 자료의 비교)

  • Youn, Yong-Hoon;Kim, Ki-Hyun;Park, Young-Hyang;Oh, Im-Sang
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.5 no.4
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    • pp.267-275
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    • 2000
  • In an effort to assess the reliability of satellite altimeter system, we conducted a comparative analysis of sea level data that were collected using the TOPEX/POSEIDON (T/P) altimeter and the 10 tide gauge (TG) stations in the satellite passing track. The analysis was made using data sets collected from marginal sea regions surrounding the Korean Peninsula at T/P cycles of 2 to 230, which correspond to October 1992 to December 1998. Because of strong tidal activity in the study area, treatment of tidal errors is a very critical step in data processing. Hence in the computation of dynamic heights from the Tn data, we adapted the procedures of Park and Gamberoni (1995) to reduce errors associated with it. When these T/P data were treated, the alias periods of M$_2$, S$_2$, and K$_1$ constitutions were found at 62.1, 58.7, and 173 days. The compatibility of the T/P and TG data sets were examined at various filtering periods. The results indicate that the low-frequency signal of Tn data can be interpreted more safely with longer filtering periods (such as up to the maximum selected values of 200 days). When RMS errors for 200-day low-pass filter period was compared among the whole 10 tidal stations, the values spanned in the range of 2.8 to 6.7 cm. The results of correlation analysis at this filtering period also showed a strong agreement between the Tn and TG data sets over the whole stations investigated (e.g., P values consistently less than 0.0001). According to our analysis, we conclude that the analysis of surface sea level using satellite altimeter data can be made safely and reasonably long filtering periods such as 200 days.

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A Study on Cold Water Damage to Marine Culturing Farms at Guryongpo in the Southwestern Part of the East Sea (경북 구룡포 해역에서의 냉수 발생과 어장 피해)

  • Lee, Yong-Hwa;Shim, JeongHee;Choi, Yang-ho;Kim, Sang-Woo;Shim, Jeong-Min
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.22 no.6
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    • pp.731-737
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    • 2016
  • To understand the characteristics and strength of the cold water that has caused damage to marine-culturing farms around Guryongpo, in the southwestern part of Korea, surface and water column temperatures were collected from temperature loggers deployed at a sea squirt farm during August-November 2007 and from a Real-time Information System for Aquaculture environment operated by NIFS (National Institute of Fisheries Science) during July-August 2015 and 2016. During the study period, surface temperature at Guryongpo decreased sharply when south/southwestern winds prevailed (the 18-26th of August and 20-22nd of September 2007 and the 13-15th of July 2015) as a result of upwelling. However, the deep-water (20-30m) temperature increased during periods of strong north/northeasterly winds (the 5-7th and 16-18th of September 2007) as a result of downwelling. Among the cold water events that occurred at Guryongpo, the mass death of cultured fish followed strong cold water events (surface temperatures below $10^{\circ}C$) that were caused by more than two days of successive south/southeastern winds with maximum speeds higher than 5 m/s. A Cold Water Index (CWI) was defined and calculated using maximum wind speed and direction as measured daily at Pohang Meteorological Observatory. When the average CWI over two days ($CWI_{2d}$) was higher than 100, mass fish mortality occurred. The four-day average CWI ($CWI_{4d}$) showed a high negative correlation with surface temperature from July-August in the Guryongpo area ($R^2=0.5$), suggesting that CWI is a good index for predicting strong cold water events and massive mortality. In October 2007, the sea temperature at a depth of 30 m showed a high fluctuation that ranged from $7-23^{\circ}C$, with frequency and spectrum coinciding with tidal levels at Ulsan, affected by the North Korean Cold Current. If temperature variations at the depth of fish cages also regularly fluctuate within this range, damage may be caused to the Guryongpo fish industry. More studies are needed to focus on this phenomenon.

Snow Influence on the Chemical Characteristics of Winter Precipitation (강설이 겨울철 강수의 화학적 특성에 미치는 영향)

  • Kang, Gong-Unn;Kim, Nam-Song;Oh, Gyung-Jae;Shin, Dae-Yewn;Yu, Du-Cheol;Kim, Sang-Baek
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.1
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    • pp.113-125
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    • 2007
  • To know the differences in ionic compositions in rain and snow as well as snow influence on the chemical characteristics of winter precipitation, precipitation samples were collected by the wet-only automatic precipitation sample, in winter(November-February) in the Iksan located in the northwest of Chonbuk from 1995 to 2000. The samples were analyzed for concentrations of water-soluble ion species, in addition to pH and electrical conductivity. The mean pH of winter precipitation was 4.72. According to the type of winter precipitation, the mean pH of rain was 4.67 and lower than 5.05 in snow. The frequencies of pH below 5.0 in rain were about 73%, while those in snow were about 30%. Snow contained 3 times higher concentrations of sea salt ion components originated from seawater than did rain in winter, mainly $Cl^-,\;Na^+$, and $Mg^{2+}$. Neglecting sea salt ion components, $nss-SO_4^{2-}$ and $NO_3^-$ were important anions and $NH_4^+$ and $nss-Ca^{2+}$ were important cations in both of rain and snow. Concentrations of $nss-SO_4^{2-}$ was 1.3 times higher in rain than in snow, while those of $nss-Ca^{2+}$ and $NO_3^-$ were 1.5 and 1.3 times higher in snow, respectively. The mean equivalent concentration ratio of $nss-SO_4^{2-}/NO_3^-$ in winter precipitation were 2.4, which implied that the relative contribution of sulfuric and nitric acids to the precipitation acidity was 71% and 29%, respectively. The ratio in rain was 2.7 and higher than 1.5 in snow. These results suggest that the difference of $NO_3^-$ in rain and snow could be due to the more effective scavenging of $HNO_3$ vapor than particulate sulfate or nitrate by snow. The lower ratio in snow than rain is consistent with the measurement results of foreign other investigators and with scavenging theory of atmospheric aerosols. Although substantial $nss-SO_4^{2-}$ and $NO_3^-$ were observed in both of rain and snow, the corresponding presence of $NH_4^+,\;nss-Ca^{2+},\;nss-K^+$ suggested the significant neutralization of rain and snow. Differences in chemical composition of non-sea salt ions and neutralizing rapacity of $NH_4^+,\;nss-Ca^{2+}$, and $nss-K^+$ between rain and snow could explain the acidity difference of rain and snow. Snow affected that winter precipitation could be less acidic due to its higher neutralizing rapacity.

Analysis on the Sexual Expression in related to Children's Social Development (<만화로 보는 그리스 로마 신화> 속 아동의 사회학습과 연관된 만화의 윤리적 표현 분석)

  • Park, Keong-Cheol;Jung, Sun-Jin;Jeong, Sun-Mee
    • Cartoon and Animation Studies
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    • s.30
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    • pp.113-137
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    • 2013
  • The accessibility and effect of cartoon on children are very significant. Since cartoon is a medium of conveying information through text and pictures, it has a characteristic of being easily approached by children than any other medium. Its accessibility to children is inevitably more exceptional than any other medium in the sense that it is a method of not only telling or reading stories but also showing stories. The main audience of is children. It has a characteristic of being easily accepted by children since it's mythology seen in cartoon than read in text. However, gods conducts are full of unethical expressions. Sexual expressions of intermarriages between mother and son, between brother and sister and between uncle and niece, as well as extramarital intercourse are very unethical that could have negative effects on children. This study analyzed the unethical expressions of gods that could have negative effects on children at current point in time. Zeus was often unfaithful to his wife with many stories about the children of Zeus that were created from extramarital intercourse. Standard of value on rational decision has been established for adult readers, but children can readily accept things since they lack their own rational decision on what's right and wrong. As an alternative to children's uncritical observatory study, there is a need for author's intervention to help children form desirable values. The purpose of this study is to analyze the sexual expressions of Zeus and gods in that could affect children's social study.

Empirical Forecast of Corotating Interacting Regions and Geomagnetic Storms Based on Coronal Hole Information (코로나 홀을 이용한 CIR과 지자기 폭풍의 경험적 예보 연구)

  • Lee, Ji-Hye;Moon, Yong-Jae;Choi, Yun-Hee;Yoo, Kye-Hwa
    • Journal of Astronomy and Space Sciences
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    • v.26 no.3
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    • pp.305-316
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    • 2009
  • In this study, we suggest an empirical forecast of CIR (Corotating Interaction Regions) and geomagnetic storm based on the information of coronal holes (CH). For this we used CH data obtained from He I $10830{\AA}$ maps at National Solar Observatory-Kitt Peak from January 1996 to November 2003 and the CIR and storm data that Choi et al. (2009) identified. Considering the relationship among coronal holes, CIRs, and geomagnetic storms (Choi et al. 2009), we propose the criteria for geoeffective coronal holes; the center of CH is located between $N40^{\circ}$ and $S40^{\circ}$ and between $E40^{\circ}$ and $W20^{\circ}$, and its area in percentage of solar hemispheric area is larger than the following areas: (1) case 1: 0.36%, (2) case 2: 0.66%, (3) case 3: 0.36% for 1996-2000, and 0.66% for 2001-2003. Then we present contingency tables between prediction and observation for three cases and their dependence on solar cycle phase. From the contingency tables, we determined several statistical parameters for forecast evaluation such as PODy (the probability of detection yes), FAR (the false alarm ratio), Bias (the ratio of "yes" predictions to "yes" observations) and CSI (critical success index). Considering the importance of PODy and CSI, we found that the best criterion is case 3; CH-CIR: PODy=0.77, FAR=0.66, Bias=2.28, CSI=0.30. CH-storm: PODy=0.81, FAR=0.84, Bias=5.00, CSI=0.16. It is also found that the parameters after the solar maximum are much better than those before the solar maximum. Our results show that the forecasting of CIR based on coronal hole information is meaningful but the forecast of goemagnetic storm is challenging.

Studies on the Construction Characteristics of Rear Garden Farmland at Joseon Palace (조선시대 궁궐 후원 농경지(農耕地) 조영의 특성)

  • Jung, Woo-Jin;Sim, Woo-Kyung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.4
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    • pp.62-77
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    • 2012
  • This study aimed to investigate the Confucian-oriented agriculture phase of the Joseon Dynasty, which was reflected at the palaces, by analyzing constructional aspects and spatial characteristics of farmlands at the palace rear gardens. The objective sites were the rear gardens of Gyeongbok Palace, Changkyung Palace, and the outside of Sinmoomoon(神武門) This study was based on literature reviews. The farmlands at the palace rear garden were constructed to self-estimate the year's harvest condition within the palaces. It was a part of the agriculture encouragement policy on governing the group of Joseon like publishing the Nongsajiksul(農事直說) and establishing the Chingyeongnye(親耕禮: king's own cultivation ceremony) and Kikokje(祈穀祭: the rite of praying for grain). In addition, farmlands of the rear garden were operated from the beginning of the state almost until the Japanese colonial era. The results were summarized as follows: First, Gyeongbok Palace rear garden's farmland which begin at the reign of Sejong(世宗) existed at the present Hyangwonji(香遠池) area. It was constructed in order to check the advanced agricultural technologies. The rear garden's farmland in Changkyung Palace, which was executed during the reign of Seongjong(成宗), was constructed right after the initial Chingyeongnye of the Joseon Dynasty. Therefore, it might be understood as the context of the king's own cultivation of the Jeokjeonchinkyung(籍田親耕). Injo(仁祖) dug for farmland in the ground of the Gyemgdeok Palace(慶德宮) though there was some stay palace, when his stay dragged out for too long. This bespeaks that those farmlands at the palace rear gardens were of great importance in the Joseon political history. The farmland near Gyeongnongjae(耕農齋), which was made during the reign of Gojong(高宗), inherited predecessor's walks of the promoting agriculture and exhibited spatial compositions such as the rear garden's farmland at Changkyung Palace. Secondly, irrigation, its water systems, the name of observatory to study farming[觀耕臺] and location requirements for farmland had something in common. It was assumed as universal forms of physiocracy-space in the Joseon Dynasty. In this study, by considering aspects of operating about vegetable garden managed by eunuchs and of the orchard in palace to cultivate fruits for national ceremonies, it could be assumed that landscape architecture of royal palace in the Joseon Dynasty did not only focus on solemnity, orderliness and fanciness but also on the practical and productive which was helpful in life. In addition, the diverse activities of productive landscape architecture led by the royal family in palaces, and the initiatively tested advanced agricultural technologies by the king were considered as an aspect of the Korean traditional specific royal palace landscape architecture. That is considered sole landscape not only to love of the people but also the 'agriculture-first' principle which were absent from other nations.

UBVI CCD Photometry of NGC 7790 (NGC 7790의 UBVI CCD 측광)

  • Choi, Dong Yeol;Kim, Hee Soo;Lim, Beomdu;Sung, Hwankyung
    • Journal of the Korean earth science society
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    • v.36 no.7
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    • pp.661-673
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    • 2015
  • UBVI CCD photometry of the intermediate age open cluster NGC 7790 has been obtained using AZT-22 1.5 m telescope (f/7.74) at the Maidanak Astronomical Observatory in Uzbekistan. NGC 7790 contains three ${\delta}$ Cep variable stars including CEa Cas, CEb Cas, and CF Cas. PSF photometry was carried out using IRAF/DAOPHOT for all observations. The total number of stars observed both in V and I filter was 1008 and the limiting magnitude was $V{\approx}22$. To determine atmospheric extinction coefficients and photometric zero points, many blue and red standard stars as well as the standard stars in the celestial equator under various airmass were observed. Photometric data were transformed into the standard Johnson-Cousins' UBVI standard system. From the analysis of UBVI color-magnitude diagram and color-color diagram, the color excess in V and I filter [$E(B-V)=0.58{\pm}0.02$], the selective extinction ratio in V and I filter [$R_V{\equiv}A_V/E(B-V)=3.02{\pm}0.09$] and distance modulus ($V_0-M_V=12.65{\pm}0.10$) of the cluster were determined. The age of the cluster was estimated to be log $age=8.05{\pm}0.05$ [yr] based on the position of these three Cepheid variables in the color-magnitude diagram, the isochrone of the Geneva group ($Ekstr{\ddot{o}}m$ et al., 2012-Z=0.019), and the isochrone of the Padova group (Bressan et al., 2012-Z=0.014) were used to compare each other. Of them, the Geneva models that considered stellar rotation well described the position of ${\delta}$ Cepheid variables in the blue loop. Although they were well consistent with standard period-luminosity relation of ${\delta}$ Cepheid variables, three Cepheid variables in NGC 7790 were, on average, brighter by about 0.5 mag than the absolute magnitude estimated from the mean period-luminosity relation at a given period.

Growth Environment Characteristics and Decline in Mt. Seunghak's Miscanthus sinensis Community (승학산 참억새군락의 생육환경 특성 및 쇠퇴에 관한 연구)

  • Park, Seul-Gi;Choi, Song-Hyun;Hong, Suk-Hwan;Lee, Sang-Cheol;Yu, Chan-Yeol
    • Journal of the Korean Institute of Landscape Architecture
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    • v.45 no.5
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    • pp.14-28
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    • 2017
  • Mt. Seunghak's Miscanthus sinensis community is not only a landscape resource in terms of cultural services within the Ecosystem Services but also a site that is visited by many mountaineers in autumn. As the current Miscanthus sinensis community has been experiencing a rapid decline due to Korean forest succession characteristics, ongoing artificial management is thought to be needed for landscape resource use. The purpose of this study was to determine growth environment characteristics and the cause of the rapid decline of the Miscanthus sinensis community in Mt. Seunghak, which is located inside a large city with a large scale and outstanding accessibility. As the Miscanthus sinensis community is the representative early vegetation that appears temporarily in dry, barren soil, the Miscanthus sinensis community in Korean forest succession tends to be unsustainable. As the current soil on Mt. Seunghak is inappropriately fertile for the Miscanthus sinensis community, other wetland woody plant communities are anticipated to succeed it. If Miscanthus sinensis community maintenance is needed for Miscanthus sinensis landscape scenery, various alternatives apart from overall Miscanthus sinensis community maintenance should be determined for cost-effective management. For example, while many byways toward the inside of the Miscanthus sinensis community have affected the Miscanthus sinensis community growth environment, the installation of wooden fences and ropes has been a control in approach. As a result of this positive effect, many byways toward the inside of Miscanthus sinensis community have been restored naturally. Through viewable range analysis, as good scenery sites on the observatory have a good viewable range on the main trail as well, if these scenery sites are intensively managed, effective Miscanthus sinensis ccommunity management will be done despite maintenance budget cutbacks. This study is expected to be used as a basic material regarding the alternatives for a sustained Miscanthus sinensis community and the possibility of cultivating other growth in poor soils of fallow fields and unused land.

Characteristics and Screening of Antioxidative Activity for the Fruit by Rubus coreanus Miq. Clones (복분자딸기 클론별 과실특성과 항산화 활성 탐색)

  • Kim, Sea Hyun;Chung, Hun Gwan;Jang, Yong Seok;Park, Young Ki;Park, Hyung Soon;Kim, Sun Chang
    • Journal of Korean Society of Forest Science
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    • v.94 no.1 s.158
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    • pp.11-15
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    • 2005
  • Fruit characteristics, saccharinity, and antioxidative activity of selected clones of Rubus coreanus, grown in Korea, well-known as edible and medical resources, frequently used and which has an excellent pharmacological activity are examined and analyzed. The results obtained from this study can be summarized as follows; Result of surveying characteristics for the fruit and saccharinity variation by collection time, there are some meaningful differences between examined clones and the collection time, exception of the fruit width. From the clones, SG 3 is the biggest in size, the highest in the saccharinity out of five clones, on the other hand, CJ 18 and SH 3 are the opposite. Meanwhile, comparing examined saccharinity factor with maximum temperature and precipitation out of daily climates at Suwon Meteorological Observatory at the same period, on the day the highest temperature is $29.5^{\circ}C$, saccharinity distinctively ascends, but on the day the precipitation is recorded 121.5 mm and next day, the saccharinity descends. Also, five-day saccharinity until the precipitation lower than 0.1 mm per day shows from 10.4 to 11.5 Brix higher than the average saccharinity of 9.7 Brix. Fifteen clones including CA 6 about fruit characteristics in terms of collection layer and saccharinity variation were examined, there is significantly difference among examined clones, but about the collection layer, only saccharinity factor has meaningful significance. For clones, MJ 11 is the biggest and excellent character of 15 clones but the saccharinity, 10.3 Brix lows a bit, MC 9 and HAE 5 are the worst fruit in character but saccharinity is 13.4 Brix and 10.6 Brix which is higher than the average saccharinity of 9.8 Brix. About saccharinity for the collection layer, the fruit average saccharinity, collected from the upper layer which is good at lightness and temperature condition, is 10.2 Brix which shows higher than the one of the fruit, 9.7 Bix and 9.5 Brix collected from the middle or the lower layer. The saccharinity of fruit collected from the middle or the lower layer is lower than the average saccharinity of 9.8 Brix out of 15 surveyed clones. Surveying antioxidative activity resulted from free radical scavenging activity about 30 clones of fruit in total, there is difference between surveyed clones. Especially, Immatured fruit extracts exhibited higher free radical scavenging activity of 94.5 to 97.5% which indicates the similarity to Ascorbic acid, unlike other clones, on the concentration of 250 to 1,000 ppm.

NEAR REAL-TIME ESTIMATION OF GEOMAGNETIC LOCAL K INDEX FROM GYEONGZU MAGNETOMETER (경주 지자기관측소 자료를 이용한 준실시간 K 지수 산출에 관한 연구)

  • Choi, K.C.;Cho, K.S.;Moon, Y.J.;Kim, K.H.;Lee, D.Y.;Park, Y.D.;Lim, M.T.;Park, Y.S.;Lim, H.R.
    • Journal of Astronomy and Space Sciences
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    • v.22 no.4
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    • pp.431-440
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    • 2005
  • Local K-index is an indicator representing local geomagnetic activity in every 3 hour. For estimation of the local K-index, a reasonable determination of solar quiet curve (undisturbed daily variation of geomagnetic field) is quiet essential. To derive the solar quiet curve, the FMI method, which is one of representative algorithms, uses horizontal components (H and D) of 3 days magnetometer data from the previous day to the next day for a specific day. However, this method is not applicable to real time forecast since it always requires the next day data. In this study, we have devised a new method to estimate local K-index in near real-time by modifying the FMI method. The new method selects a recent quiet day whose $K_p$ indices, reported by NOAA/SEC are all lower than 3, and replace the previous day and the next day data by the recent quiet day data. We estimated 2,672 local K indices from Gyeongzu magnetometer in 2003, and then compared the indices with those from the conventional FMI method. We also compared the K indices with those from Kakioka observatory. As a result, we found that (1) K indices from the new method are nearly consistent with those of the conventional FMI method with a very high correlation (R=0.96); (2) onr local K indices also have a relatively high correlation (R=0.81) with those from Kakioka station. Our results show that the new method can be used for near real-time estimation of local K indices from Gyeongzu magnetometer.