• Korean Journal of Ichthyology
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• v.33 no.2
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• pp.84-94
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• 2021

This study was conducted to elucidate the impact of invasive species, Micropterus salmoides and Lepomis macrochirus in Geumgyeji, Samgaji and Naejangji reservoirs of National Parks, Korea in 2020. In the Geumgyeji, 1,221 individuals of 11 species in 7 families were collected including M. salmoides (relative abundance, 96.3%) and L. macrochirus (0.3%), M. salmoides fed mainly on Rhinogobius brunneus (IRI, 37.2%), Odonata (25.6%), Megaloptera (11.6%), and M. salmoides (7.0%). In the results of Samgaji showed that 854 individuals of 10 species in 5 families were collected including M. salmoides (60.8%), and M. salmoides fed mainly on Decapoda (shrimp, 33.6%), Odonata (34.4%), R. brunneus (21.2%), and Zacco platypus (6.1%). In the Naejangji showed that 1,075 individuals of 13 species belonging to 7 families were collected including L. macrochirus (38.1%) and M. salmoides (9.5%), and L. macrochirus fed mainly on Branchiopoda (77.5%), Diptera (9.8%), Decapoda (4.0%) and M. salmoides fed mainly on R. brunneus (73.3%), Decapoda (21.2%). M. salmoides of Geumgyeji and Samgaji were apparently introduced more than a 10 years ago. The fish population declined rapidly since the introduction of M. salmoides. L. macrochirus of Naejangji was introduced more than 20 years ago, which increased its relative abundance to 40%. M. salmoides was introduced five to six years ago, and the fish species and population declined rapidly since the introduction of M. salmoides. Finally, we discussed the inhabitat status and management of M. salmoides and L. macrochirus in the National Park.

• 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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.spc
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• pp.78-83
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• 2008

Soybean [Glycine max (L.)] is a major source of protein for human and animal feed. Inter- and intra-genotype variation of soybean protein has been investigated by soybean researchers. However, limited sample amount of soybean single seed there is no report that investigated intra-plant variation of soybean protein within soybean plant. Recently a non-destructive NIR (near-infrared reflectance) spectroscopy using single seed grain to analyze seed protein was developed. The objectives of this study were to understand variation of seed protein content within plant and to determine the amount of minimum sample size which can represent protein content for a soybean plant. Frequency distribution of protein content within plant showed normal distribution. There was an intra-cultivar variation for protein content in soybean cultivar Seonnogkong. Difference of protein content among single plants of Seonnokong was recognized at 5% level. Seeds in lower position on plant stem tended to accumulate more protein than in higher position. There was significant difference for protein content between sample size 5 seeds and sample size of more than 5 seeds (10, 20, 30, 40, and 50 seeds) at a soybean plant with 57 seeds however no difference was recognized among sample size (5, 10, 20, and 30 seeds) at a soybean plant with 33 seeds. Around 20% seeds of soybean from single plant needed to determine the protein content to represent protein content of single soybean plant. This study is the first one to report evidence of intra-plant variation for proteincontent which detected by non-destructive NIR spectroscopy using single seed grain in soybean.

• Current Research on Agriculture and Life Sciences
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• v.6
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• pp.75-85
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• 1988

The concentration of 50 mM Nacl inhibited the shoot growth of P. nigra ${\times}$ maximowiczii in viro culture. The punctured leaves have produced so many individuals on MS basal medium with cytokinin. Especially MS basal medium with BAP 0.8mg/l showed the best shoot performance in which the average number of shoots were 127.6. For selection of NaCl tolerance shoot of poplar, punctured leaves were inoculated on MS basal medium with BAP 0.8mg/l and various concentrations of NaCl(from 10 mM to 100 mM graded by 10 mM). On the medium with over 50mM of NaCl, 13.7 to 15.7 shoots were obtained. Especially on the medium with go mM and 100mM. 10.7 and 8.3 shoots, respectively. The shoots derived from control medium (non-NaCl) were depressed growth, while the selected shoots from MS with NaCl showed good growth performance on MS basal medium with 50 mM of NaCl. From this results, we suggested that the possibility of in vitro selection to tolerance for inorganic salts in forest tree species.

• Korean Journal of Ichthyology
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• v.33 no.4
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• pp.287-296
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• 2021

This study was conducted to investigate the species composition collected by fyke net and characteristics of the Erythroculter erythropterus population in the Asan Lake and Chungju Lake from June to September, 2021. The collected fish in Asan lake were identified as 4,977 individuals of 13 species from a total of six families and in Chungju lake were identified as 2,436 individuals of 18 species from a total of eight families. The dominant species in Asan lake, both the individuals and biomass were E. erythropterus with 4,470 (89.8%) and 498,424g (84.5%). The dominant species in Chungju lake, both the individuals and biomass were E. erythropterus with 1,327 (54.5%) and 301,818 g (77.5%). The results of the community analysis showed that a dominant index value of Asan lake was 0.93, higher than 0.71 of Chungju lake, and a diversity, evenness, and richness index value of Chungju lake were higher than of Asan lake. The frequency distribution of the total length analysis of the E. erythropterus population showed the appearance rate of 1~2 year olds was high in Asan lake, and the appearance rate of more than 2 years old were high in Chungju lake. The length-weight analysis of E. erythropterus in Asan Lake and Chungju Lake showed a regression coefficient b of 3.06 and 3.04, a condition factor (K) of 0.000128 and 0.000051 with a positive slope. This study could be served as baseline data for assessing habitat characteristics based on the species composition of fishes, and identifying health conditions of E. erythropterus in Asan Lake and Chungju Lake, artificial lakes.

• Journal of Animal Science and Technology
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• v.53 no.1
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• pp.29-34
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• 2011

Using the materials collected from nine farms in a three-way cross system to produce commercial pigs produced from F1 sows (Landrace $\times$ Large White) $\times$ Duroc, the power of individual discrimination and parentage of the 13 microsatellite (MS) marker set that has been suggested for individual/brand identification (traceability) was empirically tested. Initially, genotypes of the parental population ($F_1$ sows and Duroc), and commercial pigs were determined and the genotype frequency and polymorphic index were estimated using the Cervus 2.0 program. The probability of identity among genotypes of random individuals, that random half sibs and that of full sib individuals, based on the genotypes from 91 $F_1$ sows and Duroc were expected to be $4.94{\times}10^{-34}$, $8.16{\times}10^{-23}$ and $2.01{\times}10^{-08}$, respectively, using the API-CALC version 1.0 program. When commercial pigs were included, the estimates increased to $3.74{\times}10^{-35}$, $5.48{\times}10^{-25}$ and $2.96{\times}10^{-11}$, respectively. For the empirical verification of the estimated powers of individual discrimination and parentage, the parentage test was performed for 452 commercial pigs using PAPA version 2.0, and individuals with the same genotype were investigated using the Cervus version 2.0 program. Parents for all commercial pigs were successfully estimated and no identical individual was identified in the pedigree. Although the individual discriminating power was not fully verified because of the lack of individuals corresponding with the theoretical power, the 100% efficiency of parentage test was clearly confirmed. Therefore, we believe that the 13 MS marker set in conjunction with management record/information for the pig production kept in a farm/brand should be useful in the pork traceability in a brand unit.

• Korean Journal of Environment and Ecology
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• v.35 no.4
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• pp.408-423
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• 2021

We established and monitored survey sites in seven regions of Mt. Jiri to investigate population decline and change of the Korean fir (Abies koreana) over a ten-year period from 2009 to 2018. With the exception of one site (Seseok), the six remaining ones all showed a four-layer stratification structure. The importance value of Korean firs in all of the survey areas decreased significantly by 28.5%, from 55.7% in 2009 to 39.8% in 2018. The average population of objects with a diameter at breast height (DBH) of 5cm or more in all survey sites was 711 objects/ha in 2018, and the cumulative death rate from 2009 to 2018 was 10.8%. Among the death types, DS (dead standing) was the most dominant, comprising 82.4% of the total survey area. However, in Banyabong 1, which had a high gradient of 35°, the death types other than DS accounted for 44.2%. We estimate that A. koreana can maintain a stable population as its distribution type for each diameter class in the Saeseokpyeongjeon site showed a reverse-J shape. The average annual ring growth in all survey sites was 1.09 mm/year, with the most abundant growth observed in the Seseokpyeongjeon site, which was formed mainly by a subtree layer. The growth ring survey showed the estimated average age of A. koreana population in the Byeoksoryeong and Banyabong 1 sites to be 102 and 91 years, respectively, a general downward trend of vitality since 2013.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06b
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• pp.363-365
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• 2012

데이터의 규모 및 활용도, 그리고 사용자 접근성 측면에서 실세계 데이터에서 가장 중요한 이슈가 되는 것은 비디오 데이터이다. 장르나 등장인물, 배경 등이 매우 상이한 대량의 비디오 데이터들이 등장하고 있기 때문에, 통일된 사전지식을 이용한 비디오 데이터 분석이 매우 비현실적이 되어가고 있으며 사전지식을 활용하지 않는 비디오 분석기법의 중요성이 커지고 있다. 본 논문에서는 진화 파티를 필터링과 우점 이미지를 이용하여 비디오 데이터를 분절(Segmentation)하는 기법을 소개한다. 이미지 분절화 과정에서 해결해야 할 난점은 시점 변화 및 움직임 등에 의해 발생하는 사소한 변화가 컴퓨터 관점에서는 무시하기 어려운 큰 변화로 해석될 수 있다는 점이다. 동일장면에서의 시점 변화와 같은 사소한 변화로 인하여 동일 세그먼트를 추정하지 못하는 어려움을 해결하기 위하여 우리는 이미지 일부를 표현하는 파티클의 개체군을 생성하여 협력적인 방식으로 개별 이미지 세그먼트를 표현하는 방법을 개발하였다. 또한 동일 인물의 움직임과 같은 변화에 대응할 수 있도록 진화 파티를 필터링 방법을 컬러 히스토그램 방법과 결합하여 추론 성능을 한층 개선하였다. 실제 TV 드라마에 대하여 수행된 인간 평가자의 분절 평가 결과와 비교하여 제안 방법의 성능을 확인하였다.

• The Journal of the Acoustical Society of Korea
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• v.3 no.2
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• pp.59-68
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• 1984

어군의 밀도를 음파로 추정할 때 어군의 총후방 산란 단면적이 어류개체의 후방 산란 단면적을 random phase로 합한 것과 같다는 가정에 대하여 실험적 검증을 시도하였다. 어체의 길이 대 음파의 파장비가 23일 때 두 마리와 세 마리의 숭어에 대하여 실시한 실험에서 전 산란각에 대한 편균이 random phase로 합할 때 보다 -1.7dB와 +1dB씩 편차를 보였다. 그러나 전체적으로는 in phase와 out phase sum 사이에서 변화함을 보였고, 최대오차는 in phase로 합해질 때로서 실제의 어군밀도 n에 비 해 최고 n\sup 2\에 이르기까지 추정 가능함을 실험결과는 보여주고 있다. 더욱이 이러한 결과는 어체간 의 간격변화에는 거의 무관하였으므로 소나무 빔폭이나 어군의 분포에 상관없이 빔폭 사이에 있는 어군 의 마리수에만 퐁후방 산란 단면적이 관계된다는 결론을 얻을 수 있었다.