• Journal of Environmental Impact Assessment
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• v.22 no.6
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• pp.745-751
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• 2013

Environmental Specimen Banks (ESBs) have been established widely in the world since 1979 for monitoring long-term bio-accumulation of environmental pollutants. The ESBs perform the retrospective analysis of representative biological samples collected regularly and store them in cryogenic condition. In Korea, National Environmental Specimen Bank (NESB) was established in 2009. Since then, NESB had prepared the standard operating procedures (SOPs) for the seven kinds of specimens (Red Pine (Pinus densiflora), Common Carp (Cyprinus carpio), and etc.) for monitoring the effect of environmental pollution on the terrestrial ecosystem and river ecosystem. In 2012, NESB added Black-tailed Gull (Larus crassirostris)'s eggs to the list of the environmental specimen for monitoring marine environmental pollution. In this study, we sampled the eggs of the Black-tailed Gull on two islands (Baekryeongdo of the West Sea and Hongdo of the South Sea). Especially, we selected eggs which remained in the early stages of embryo development for certifying the consistent and stable monitoring for environmental pollutants in egg contents. However, it was not considered to classify an order of eggs per clutch in this study. It is known that the concentration variations of pollutants exist among eggs in one clutch. Therefore, it is needed to consider the positions of eggs in the laying sequences to meet the objective of bioaccumulation monitoring. We collected 30 eggs in each site but the amount may be insufficient to achieve storage target (over 2,000 g). Therefore, we need to consider an optimal sampling size.

• Research in Plant Disease
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• v.19 no.2
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• pp.102-107
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• 2013

The percent of diseased fruit by Diaporthe citri was the most 16.8% in 2010 and the least 3.8% in 2005, and the average was 8.8% from 2003 to 2012. The degrees of disease incidence were relatively high, 17.0, 22.6, 19.2 and 18.9%, in 2003, 2004, 2007 and 2010, respectively. The percent of diseased fruit by Elsinoe fawcettii was the most 0.72% in 2004, and then gradually decreased to 0.08% in 2008, and the average was from 0.28% from 2004 to 2011. In case of canker by Xanthomonas citri subsp. citri, the percent of diseased fruit was the most 2.19% in 2004, and gradually decreased to 0.08 and 0.10% in 2009 and 2010, respectively. The average was 0.81% from 2004 to 2012. The melanose by D. citri was most in south-east area of Jeju Island, and east and west in case of canker. The melanose symptoms were initially appeared from mid June, mainly peaked late of July to late August. The canker symptoms were initially produced on leaves of natsudaidai and grapefruit cultivated in open field middle of June in 2010 and 2011 and late of May in 2012. The scab disease was firstly appeared approx. early or mid May and then rapidly increased late of May to middle of June. The inoculum was mainly produced from dead twigs late June to early of August.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.3
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• pp.170-174
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• 1998

The water quality of offshore waters around the Korean coast was evaluated by bioassay using gametes, embryoss and early development systems of a sea urchin species Hemicentrotus pulcherrimus. The results show that despite the inflows of several river systems, the west coast maintain the grade II water. This is thought to be due to the decrease in pollutant input resulting from the purification of inflow rivers (e.g., the control of waste water discharge and the construction of sewage treatment facilities), and the dilution of pollutants by a strong tidal mixing with a large difference between the ebb and flood tides. However, Asan, Hampyong and Chonsu bays, where circulations of water are relatively poor, and the Kunsan and Mokpo harbors which are influenced by pollutants from neighboring cities have shown the grade III water. The south coast has maintain the grade II or III because developments of sea urchins were moderately or strongly inhibited. Also, Kangjin, Duekryang, Kwangyang, Masan, and Jinhae bays where water circulations are relatively poor, show the grade III water, with strong inhibitions of the early development of sea urchins. The east coast has maintained the grade I and II due to monotonous coastlines and smooth circulation of sea water. However, Chongcho Lake shows the worst water quality due to the breakwater which is constructed to maintain port functions.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.2
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• pp.104-109
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• 2013

The spawning characteristics of Hexagrammos agrammus and Hexagrammos otakii was directly observed in coastal regions of the Yellow Sea and South Sea during the spawning seasons using scuba diving. The territorial male H. agrammus showed different body size, nuptial coloration and nest location compared to those of H. otakii, even though both species caring egg masses were found at the almost same depths. In the West sea, a relatively small guardian H. agrammus male protects 1-2 egg masses laid on a clump of red algae within his territory. The territorial males in red nuptial coloration and their egg masses were well camouflaged in their surroundings. Contrary to H. agammus, a guardian H. otakii male in yellowish nuptial coloration protects 4-8 egg masses in a nest. In addition, their nests were located on the relatively open environments such as discarded fishing nets, rock crevices and a clump of algae. The results of present study shows that even though both of two species belonged to Hexagrammidae, they have different strategies for spawning and protecting their egg masses.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.1
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• pp.9-16
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• 2004

Parapenaeopsis tenella occurs widely on the south and west coasts of Korea. Sex ratio showed seasonal variations, with a mean value of 48.6% for the females. The species produces one cohort a year, with the ovaries ripening from July to August. Insemination took place from July to August, as more than half of the females sampled in the study over 14 mm CL were inseminated. Gonadosomatic index (GSI) reached the maximum between July and August. The smallest mature female was 11 mm CL. Size at 50% sexual maturity ($CL_{50}$), determined from both mature females and inseminated females, was 12.53 mm and 12.28 mm CL, respectively. The life span of females appeared to be 14-15 months according to size frequency distributions, while that of the male was 13-14 months. Population growth was estimated by the modified von Bertalanffy growth function incorporating seasonal variation in growth. Based on the growth parameters (K = 1.22 $yr^{-1}$ and $L_{\infty}$ = 21.99 mm CL for females, and K = 2.00 $yr^{-1}$ and $L_{\infty}$ = 15.00 mm CL for males) growth curves showed that females grew faster and reached a larger size at age than males.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.32.1-32.1
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• 2017

To dynamically and chemically understand how filaments, dense cores, and stars form under different environments, we are conducting a systematic mapping survey of nearby molecular clouds using the TRAO 14 m telescope with high ($N_2H^+$ 1-0, $HCO^+$ 1-0, SO 32-21, and $NH_2D$ v=1-0) and low ($^{13}CO$ 1-0, $C^{18}O$ 1-0) density tracers. The goals of this survey are to obtain the velocity distribution of low dense filaments and their dense cores for the study of their origin of the formation, to understand whether the dense cores form from any radial accretion or inward motions toward dense cores from their surrounding filaments, and to study the chemical differentiation of the filaments and the dense cores. Until Feb. 2017, the real OTF observation time is 460 hours. We have almost completed mapping observation with four molecular lines ($^{13}CO$ 1-0, $C^{18}O$ 1-0, $N_2H^+$ 1-0, and $HCO^+$ 1-0) on the five regions of molecular clouds (L1251 of Cepheus, Perseus west, Polaris south, BISTRO region of Serpense, California, and Orion B). The maps of a total area of $7.38deg^2$ for both $^{13}CO$ and $C^{18}O$ lines and $2.19deg^2$ for both $N_2H^+$ and $HCO^+$ lines were obtained. All OTF data were regridded to a cell size of 22 by 22 arcseconds. The $^{13}CO$ and $C^{18}O$ data show the RMS noise level of about 0.22 K and $N_2H^+$ and $HCO^+$ data show about 0.14 K at the velocity resolution of 0.06 km/s. Additional observations will be made on some regions that have not reached the noise level for analysis. We are refining the process for a massive amount of data and the data reduction and analysis are underway. This presentation introduces the overall progress from observations to data processing and the initial analysis results to date.

• Journal of Environmental Science International
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• v.19 no.3
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• pp.295-304
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• 2010

Actual evapotranspiration (AET) in the Suyeong-gu was estimated and correlations between AET and meteorological factors were analyzed. The study area was Suyeong-gu lay at the east longitude $129^{\circ}$ 05' 40" ~ 129$^{\circ}$ 08' 08" and north latitude $35^{\circ}$ 07' 59" ~ $35^{\circ}$ 11' 01". The Kumryun mountain, the Bae mountain, the Suyeong river and the Suyeong bay are located on west, north, northeaster and south side in the study area, respectively. AET was estimated using precipitation (P), potential evapotranspiration (PET) and plant-available water coefficient. Meteorological factors to estimate PET were air temperature, dewpoint temperature, atmospheric pressure, duration of sunshine and mean wind speed (MWS). PET and AET were estimated by a method of Allen et al. (1998) and Zhang et al. (2001), respectively. PET was the highest value (564.45 mm/yr) in 2002 year, while it was the lowest value (449.95 mm/yr) in 2003 year. AET was estimated highest value (554.14 mm/yr) in 2002 year and lowest value (427.91 mm/yr) in 2003 year. Variations of PET and AET were similar. The linear regression function of AET as PET using monthly data was AET=0.87$\times$PET+3.52 and coefficient of determination was high, 0.75. In order to analyze relationship between the evapotranspiration and meteorological factors, correlation analysis using monthly data were accomplished. Correlation coefficient of AET-PET was 0.96 high, but they of AET-P and PET-P were very low. Correlation coefficients of AET-MWS and PET-MWS were 0.67 and 0.73, respectively. Thus, correlation between evapotranspiration and MWS was the highest among meteorological factors in Suyong-gu. This means that meteorological factor to powerfully effect for the variation of evapotranspiration was MWS. The linear regression function of AET as MWS was AET=84.73$\times$MWS+223.05 and coefficient of determination was 0.54. The linear regression function of PET as MWS was PET=83.83$\times$MWS+203.62 and coefficient of determination was 0.45.

• Journal of the Korean earth science society
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• v.30 no.3
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• pp.344-353
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• 2009

By measuring the brightness of night sky, we have investigated light pollution around the observatory in the College of Education, Seoul National University. As a result of measuring the extinction coefficient and photometric constants by standardization, in January 28, 2009, the extinction coefficient found to be $k_B$=0.359 and photometric constant was $C_B$=4.397. In March 27, 2009, extinction coefficients were $k_B$=0.896 and $k_V$=0.725, and photometric constants were $C_B$=6.235 and $C_V$=6.027. Brightness of the night sky was measured from east, west, south, and north each by altitude of $20^{\circ}$, $40^{\circ}$, $60^{\circ}$, $75^{\circ}$ and $90^{\circ}$. Data reduction and analysis was based on IRAF. Seeings for the each day of observation were 5.1 and 5.7 arcseconds in January 28 and March 27, respectively. Night sky spanned the magnitude range of $16{\leq}m_V$, $m_B{\leq}18$ We found that the brightness of night sky located at downtown was twice to four times brighter. On these observational conditions, limiting magnitude within 40cm-telescope becomes 11-13 magnitudes. Compared with Jan 28 and Mar 27, night sky brightness of January is 1 magnitude fainter than that of March in B filter.

• Journal of the Korean Geographical Society
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• v.49 no.6
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• pp.812-832
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• 2014

We analyzed physical and chemical properties of sediments from 20 subtidal points and 9 beach points to define sedimentary environment between summer and winter of Shindu Marine Protected Area. Means of particle size in summer were generally finer than winter's. There was distinctively spatial pattern that particle sizes became increasingly fine as west direction and apart from beach in summer, but this pattern was not shown in winter. Coarse sediments were prevailed in winter. To explain these patterns, we propose possible two causes which are spatially different water depth condition related with seasonal wave climate or fine sediment input from an estuary located in south of this area during summer rainy season. Contents of exchangeable cations of sediment in summer were shown $Na^+$>$Ca^{2+}$>$Mg^{2+}$>$K^+$ in order, but those of winter were shown $Na^+$>$Mg^{2+}{\fallingdotseq}Ca^{2+}$>$K^+$. Contents of $Na^+$, $Mg^{2+}$, and $K^+$ were related with contents of fine sediment and showed high correlation in each other. These relations were not shown between $Ca^{2+}$ and others. Our results show that there are spatio-temporal unique sedimentary environments between subtidal zone, beach, and dune near Shindu Marine Protected Area. Therefore, we should consider these spatio-temporal patterns for environmentally sound management of Shindu coastal system.

• Convergence Security Journal
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• v.14 no.3_2
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• pp.83-91
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• 2014

International society got a severe shock from terrorism of hostage, abduction and murder that was committed on a target of Israel athlete delegation in Munich Olympics, West Germany by Black September, a Palestine terrorism organization. Korea with 1986 Asian Games and 1988 Olympics ahead was directly and indirectly exposed to threats of North Korea's nation-support terrorism, a military provocation and a local war limited warfare. This study explores the roles of the police at the time of the National Police Headquarters with regard to counter-terrorism, and analyzed academic research trends of Studies of Counter-terrorism published by the same office between 1983 and 1990. Looking into them shows a fact firstly, that the most frequently appearing key words in common were "terrorism," "hostages," "measures," and "international," etc. Secondly, before and after 1988 Olympics, the key word "Olympics" was frequently addressed. Thirdly, looking at the difference by the year, the key word, "policies of defense and borderlands" was frequently addressed between 1983 and 1984, "terrorism against South Korea," and "civil aircraft" frequently addressed in 1985, and "corporate" in 1986. In 1987, the key word "terrorism trends" was addressed, and in 1990, "international terrorism," and "separatism" were used.