• Journal of Advanced Navigation Technology
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• v.7 no.2
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• pp.128-134
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• 2003

In this paper, we investigated the degree of compensation for WDM channel signal distortion due to chromatic dispersion, self phase modulation (SPM) and cross phase modulation (XPM) as a function of transmission length using mid-span spectral inversion (MSSI) compensation method. The considered system is $3{\times}40$ Gbps intensity modulation direct detection (IM/DD) WDM transmission system. This system has highly nonlinear dispersion shifted fiber (HNL-DSF) as a nonlinear medium in optical phase conjugator (OPC). We confirmed that the transmission length is more increased by applying MSSI to distorted signal due to chromatic dispersion, SPM and XPM as dispersion coefficient of fiber becomes higher. And the compensation degree of distorted WDM channels due to chromatic dispersion, SPM and XPM becomes better stable as dispersion coefficient of fiber becomes higher.

• Journal of Advanced Navigation Technology
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• v.7 no.1
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• pp.14-21
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• 2003

We investigated the optimum pump light power compensating distorted WDM signal due to both chromatic dispersion and self phase modulation (SPM). The considered system is $3{\times}40$ Gbps intensity modulation direct detection (IM/DD) WDM transmission system with path-averaged intensity approximation (PAIA) mid-span spectral inversion (MSSI) as compensation method. This system have highly nonlinear dispersion shifted fiber (HNL-DSF) as nonlinear medium of optical phase conjugator (OPC) in the mid-way of total transmission line. We confirmed that HNL-DSF is an useful nonlinear medium in OPC for wideband WDM transmission, and the excellent compensation is obtained when the pump light power of HNL-DSF OPC was selected to equalize the conjugated light power into the second half fiber section with the input WDM signal light power depending on total transmission length. By this approach, it is verified the possibility to realize a long-haul high capacities WDM system by using PAIA MSSI compensation method, which have HNL-DSF OPC with optimal pump light power depending on transmission length.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.74-74
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• 2019

한라산은 남한에서 가장 높은 산으로 해발고도는 1,950m이고 그 면적은 약 9,100ha로 대한민국 최대의 섬제주의 중심에 자리하고 있다. 한라산은 특산식물이 36종이나 발견되어 국내 외적으로 생물적인 가치와 보전적인 가치를 인정받아온 곳이다. 본 연구에서는 한라산 성판악에서 백록담으로 이어지는 동사면의 해발고도 1,500m 부근의 진달래밭대피소 인근에 위치한 5ha 장기생태 연구 지역 식생조사를 통해서 조사된 자생 식물종을 정리하였다. 관속식물은 31과 44속 56종 등 총 56분류군으로 조사되었으며, 조사지역에서 확인된 산림청지정 희귀식물은 구상나무(LC), 주목(VU), 섬매발톱나무(DD), 개족도리풀(LC), 시로미(VU), 게박쥐나물(LC), 사철란(LC) 등 7분류군이 확인되었고, 특산식물로는 구상나무, 족도리풀, 제주조릿대, 산제비란 등 4분류군이 확인되었다. 식물구계학적 특정식물은 I등급은 일엽초, 윤노리나무, 야광나무, 큰천남성 등 6분류군, II등급으로는 두루미꽃, 홍괴불나무, 마가목, 산개벚지나무, 다람쥐꼬리 등 10분류군, III등급은 만년석송, 구상나무, 애기괭이밥, 호자덩굴 등 8분류군, IV등급은 시로미 그리고 V등급은 설앵초가 각각 1분류군으로 조사되었다. 한라산 아고산대의 대표 우점종인 구상나무는 특산식물이자, 식물구계학적 특정식물 III등급이며, 산림청지정 희귀식물 약관심종으로 추가 연구를 통하여 보전관리방안이 수립되어야 하는 것으로 판단된다.

• Korean Journal of Environment and Ecology
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• v.32 no.5
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• pp.445-468
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• 2018

The purpose of this study was to investigate the distribution of vascular plants growing at the Mt. Daedun provincial park area in the boundary between Nonsan-si, Geumsan-gun, Chungcheongnam-do and Wanju-gun, Jeollabuk-do, Korea. We collected the vascular plants 9 times from May 2016 to July 2017. The flora of Mt. Daedun was classified as a total of 434 taxa comprising of 95 families, 278 genera, 388 species, 3 subspecies, 38 varieties and 5 forma. Among them, the endemic plants in Korea that the investigation found were 11 taxa including Broussonetia kazinoki Siebold, Clematis trichotoma Nakai, Thalictrum actaefolium var. brevistylum Nakai, etc. It also found rare plant species, as designated by the Korea Forest Service were 6 taxa including 5 grade LC taxa such as Eranthis stellata Maxim., Viola albida Palib., and Scopolia japonica Maxim. and 1 grade DD taxa, Scrophularia koraiensis Nakai. The special floristic plants were a total of 35 taxa such as 9 taxa in degree III (Eranthis stellata Maxim., Stewartia pseudocamellia Maxim., Acer palmatum Thunb., etc.), 7 taxa in degree II (Equisetum hyemale L., Potentilla dickinsii Franch.&Sav., Viola orientalis (Maxim.) W. Becker, etc.) and 19 taxa in degree I (Dryopteris crassirhizoma Nakai, Cephalotaxus koreana Nakai, Ulmus parvifolia Jacq., etc.) to provide basic data. No taxa in grade V or IV were found. The naturalized plants were 34 taxa including Rumex acetosella L., Phytolacca americana L. and Chenopodium album L., and the percentage of urbanization index was 10.6% while the naturalized plant index was 7.7%.

• Journal of Life Science
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• v.18 no.8
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• pp.1090-1095
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• 2008

Marbling (intramuscular fat) is an important factor in determining meat quality in Korean beef market. A grain based finishing system for improving marbling leads to inefficient meat production due to an excessive fat production. Identification of intramuscular fat-specific gene might be achieved more targeted meat production through alternative genetic improvement program such as marker assisted selection (MAS). We carried out ddRT-PCR in 12 and 27 month old Hanwoo steers and detected 300 bp PCR product of the inducible cAMP early repressor (ICER) gene, showing highly gene expression in 27 months old. A 1.5 kb sequence was re-sequenced using primer designed base on the Hanwoo EST sequence. We then predicted the open reading frame (ORF) of ICER gene in ORF finder web program. Tissue distribution of ICER gene expression was analysed in eight Hanwoo tissue using realtime PCR analysis. The highest ICER gene expression showed in Small intestine followed by Longissimus dorsi. Interestingly, the ICER gene expressed 2.5 time higher in longissimus dorsi than in same muscle type, Rump. For gene expression analysis in high- and low marbled individuals, we selected 4 and 3 animal based on the muscle crude fat contents (high is 17-32%, low is 6-7% of crude fat contents). The ICER gene expression was analysed using ANOVA model. Marbling (muscle crude fat contents) was affected by ICER gene (P=0.012). Particularly, the ICER gene expression was 4 times higher in high group (n=4) than low group (n=3). Therefore, ICER gene might be a functional candidate gene related to marbling in Hanwoo.

• BMB Reports
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• v.40 no.5
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• pp.757-764
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• 2007

Marbling of cattle meat is dependent on the coordinated expression of multiple genes. Cattle dramatically increase their intramuscular fat content in the longissimus dorsi muscle between 12 and 27 months of age. We used the annealing control primer (ACP)-differential display RT-PCR method to identify differentially expressed genes (DEGs) that may participate in the development of intramuscular fat between early (12 months old) and late fattening stages (27 months old). Using 20 arbitrary ACP primers, we identified and sequenced 14 DEGs. BLAST searches revealed that expression of the MDH, PI4-K, ferritin, ICER, NID-2, WDNMI, telethonin, filamin, and desmin (DES) genes increased while that of GAPD, COP VII, ACTA1, CamK II, and nebulin decreased during the late fattening stage. The results of functional categorization using the Gene Ontology database for 14 known genes indicated that MDH, GAPD, and COP VII are involved in metabolic pathways such as glycolysis and the TCA cycle, whereas telethonin, filamin, nebulin, desmin, and ACTA1 contribute to the muscle contractile apparatus, and PI4-K, CamK II, and ICER have roles in signal transduction pathways regulated by growth factor or hormones. The final three genes, NID-2, WDNMI, and ferritin, are involved in iron transport and extracellular protein inhibition. The expression patterns were confirmed for seven genes (MDH, PI4-K, ferritin, ICER, nebulin, WDNMI, and telethonin) using real-time PCR. We found that the novel transcription repressor ICER gene was highly expressed in the late fattening stage and during bovine preadipocyte differentiation. This information may be helpful in selecting candidate genes that participate in intramuscular fat development in cattle.