• Title/Summary/Keyword: 80,000년

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Seed Inflow Characteristics of the Korean Red Pine according to Harvest Type in Natural Regeneration Forests (소나무 천연갱신지의 목재수확 유형별 종자 유입 특성)

  • Junmo Chung;Sang Tae Lee;Hyun Seop Kim;Sang Hoon Chung
    • Journal of Korean Society of Forest Science
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    • v.112 no.3
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    • pp.331-339
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    • 2023
  • This study was conducted to identify seed inflow characteristics according to harvest typeand to provide basic data for developing a regeneration technology for secondary growth forests in Korean red pine (Pinus densiflora) succession forest formation by natural regeneration. Experimental sites were established by applying seed tree (single and group) and clear-cutting methods (10- 20- 30-m strip and 20- 30- 40-m patch). The seed inflow characteristics of the natural regeneration site were analyzed for 6 years from 2014. Most seeds were flowed to the regeneration stand from October to November. In years with good seed fructification, more than 80% were flowed in October. The average annual seed inflow by harvest type was highest in the seed tree area (296,000 seeds/ha/yr), followed by the 20-m patch clear-cutting area (291,000 seeds/ha/yr) and 10-m strip clear-cutting area (281,000 seeds/ha/yr). The distribution uniformity of seed inflow according to treatment was analyzed in the order of the 20-m strip clear-cutting area (52.2), 20-m patch clear-cutting area (52.9), and 10-m strip clear-cutting area (56.1). As a result, the 10-m strip and 20-m patch clear-cutting areas with relatively small harvest areas showed high seed inflow and distribution uniformity.

Conservation of Removing Surface Contaminants on Silla monument at Jungsung-ri using Nd:YAG Laser Cleaning System (Nd/YAG레이저를 이용한 포항중성리신라비 표면오염물 제거와 보존처리)

  • Lee, Tae Jong;Kim, Sa Dug;Lee, Joo Wan;Oh, Jung Hyeon;Lee, Myeong Seong
    • Korean Journal of Heritage: History & Science
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    • v.44 no.4
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    • pp.142-153
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    • 2011
  • 'Silla Monument Stone in Jungseong-ri, Pohang' was discovered in Pohang City, Gyeongsangbuk Province of Korea in 2009. The monument stone with irregular shape has dimensions of maximum height of 105cm, width of 47.6~49.6cm, thickness of 13.8~14.7cm and weight of 115kg. The results of monument stone was found to be granitite. Conservation treatment procedure was carried out in the order of production of Weathering map, cleaning of surface pollutants, consolidation using ethyl silicate. Black pollutant(crust) that covered more than 60% of the surface was analyzed first in order to remove the pollutants on the surface of the monumental stone by cleaning of surface pollutants using laser. The purpose on analysis was not only to verify the pollutants on the stone but also to carry out preliminary cleaning by securing rocks with same pollutant as the monumental stone. As the results of analysis using p-XRF(PMI. INNOV-X, USA) on the site, high level of Mn and Fe were detected, and the analysis of small section that had been fallen off with SEM/EDX for the purpose of quantitative analysis also detected high level of Mn. The Similar contaminants on Stone secured in the manner described above were made into 10 samples ($5cm{\times}5cm$) and was subjected to preliminary cleaning by Nd-YAG Laser(Laser&Physics, Korea). The results of surface observation through portable microscope during cleaning revealed that the power of 460mJ, wavelength of 1064nm and irradiation frequency of 1,800~2,300 per $25cm^2$ were most effective. Evaluation on the preservative treatment was made through confirmation of the extent of removal through color-difference meter measurement and component analysis prior to and following removal of the pollutants. As the result of color-difference meter measurement increase in the brightness was evidenced by the increase in the brightness ($L^*$)value from 33 to 49, and it was possible to ascertain the reduction in the pollutants as the content of Mn was reduced by about 80% from $50,000{\pm}5,000ppm$ to $10,000{\pm}2,000pmm$ from the result of component analysis.

Environmental Assessment for Acid Mine Drainage by Past Coal Mining Activities in the Youngwol, Jungseon and Pyungchang areas, Korea (영월, 정선 및 평창지역 폐 석탄광 산성광산배수의 환경오염 평가)

  • 정명채
    • Economic and Environmental Geology
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    • v.36 no.2
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    • pp.111-121
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    • 2003
  • The objective of this study is to investigate the physical and chemical properties for environmental assessment of water system affected by acid mine drainage (AMD) from coal mining activities in the Youngwol, Jungseon and Pyungchang areas in Korea. During November 2000 to July 2002, 6 times of water samples were collected season-ally from acid mine drainage and nearby streams at 13 coal mines in the study area. The physical and chemical properties including pH, Eh, TDS, salinity, bicarbonates and DO were measured in the field. Eighteen cations includ-ing Al, Ca, Fe, Mg, Mn and Zn, and 6 anions including nitrates and sulfates were also analyzed by ICP-AES and If, respectively. Acid water from the Jungam coal mine has typical characteristics of AMD with very low pH(3∼4) and high TDS(1,000∼5,000 mg/1). Relatively high concentrations(mg/kg) of heavy meals, especially for Al(380), Fe(80), Mn(44) and Zn(8), were found in water samples from the Jungam coal mine area. Water samples from the Seojin, Sebang and Sungjin coal mines also contained over 50 mg/l of Al, >100 mg/1 of Fe and )10 mg/1 of Mn. In addition to anioins, over 1,000 mg/l of sulfate was found in several water samples. Seasonally, the concentrations of metals and sulfates varied; wet season samples were relatively higher in metals and sulfates than dry season samples. It is needed to establish the proper remediation and environmental monitoring of the AMD continuously.

Water Quality Variations due to Tidal Change in the Lower Part of the Nagdong River (조석에 따른 낙동강 하류수질의 변화)

  • KIM Yong-Gwan;CHANG Dong-Suck;MOON Hong-Young
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.18 no.2
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    • pp.109-118
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    • 1985
  • This experiment was carried out to evaluate the water quality in the lower part of the Nagdong river in Korea. Three hundred and sixty water samples were collected from the 15 stations from December 1981 to November 1982 by tide(see Fig.1). Water temperature, pH, chloride ion, salinity, total coliform, fecal coliform, viable cell count and the composition of coliform were observed to evaluate the water quality. The variations of water temperature was ranged from $2.0^{\circ}C\;to\;29.5^{\circ}C$ and as mean value from $15.8^{\circ}C\;to\;18.9^{\circ}C$. The range of pH was 6.00-8.88 and 7.20-7.96 as mean value. The concentration of chloride ion from St. 1 to 5 was higher as 17.51-771 mg/l in flood tide than 13.12-264.58 mg/l in ebb tide. Specially, water quality at St.1 (Samrangjin) which located about 46 km far from Hadan was also influenced by tide. Salinities of water in flood tide were a litte higher ($11.05{\sim}31.08\%0$) than those of in ebb tide ($7.80{\sim}29.28\%0$). Total coliform MPN's ranged from 3.6/100 m/l to 460,000/100ml. The geometric mean value of the upper area (included St. $1{\sim}3$) was $259{\sim}538/100ml$, that of the middle area (included St. $4{\sim}6$) was $1,097{\sim}39,544/100ml$ for it leveled heavy contamination. Specially, in the ebb tide St. 10 was influenced by St. 6 and 7. In the upper area, the geometric mean value of fecal coliform MPN's was $109{\sim}199/100ml$ but in the area in cluded St. 5, 6 and 7 were heavily contaminated by domestic sewage, waste water from the factories area and bird's excrement. Composition of coliform was $17\%$ Escherichia coli group, $33\%$ Citrobacter freundii group, $28\%$ Enterobacter aerogenes group and $21\%$ others. Plate count of samples was varied from <30 to $3.9{\times}10^4/ml$ during the study period.

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Spatial and Temporal Variation of Dissolved Inorganic Radiocarbon in the East Sea (동해 용존무기탄소 중 방사성탄소의 분지별 비교 및 시간에 따른 변화)

  • Sim, Bo-Ram;Kang, Dong-Jin;Park, Young Gyu;Kim, Kyung-Ryul
    • Ocean and Polar Research
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    • v.36 no.2
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    • pp.111-119
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    • 2014
  • This study examined the spatial and temporal variation of dissolved inorganic radiocarbon in the East Sea. Five vertical profiles of radiocarbon values were obtained from samples collected in 1999 in three basins (Japan Basin, Ulleung Basin, Yamato Basin) of the East Sea. Radiocarbon values decreased from 63- 85‰ at the surface to about -50‰ with increasing depth (up to 2,000 m) and were nearly constant in the layer deeper than 2,000 m in all basins. Radiocarbon values did not show significant basin-to-basin differences in the surface and the bottom layers. In the intermediate layer (200-2,000 m), however, they decreased in the order of Japan Basin > Ulleung Basin > Yamato Basin, which is consistent with the suggested circulation pattern in the intermediate layer of the East Sea. Radiocarbon was found to have decreased at ~2%/year in the surface water of the East Sea. In contrast, in the interior of the East Sea, radiocarbon values have increased with time in all three basins. In the Central Water, the annual increase rate was about 3.3‰, which is faster than the rates in the Deep and Bottom Waters. The radiocarbon in the Deep and Bottom Waters had increased until mid-1990s, after which time it has been almost constant.

Reirradiation in Rcurrent Cervical Cancer Following Definite Radiation Therapy (근치적 방사선치료 후 재발한 자궁경부암의 재 방사선치료)

  • Kim, Jin-Hee;Choi, Tae-Jin;Kim, Ok-Bae
    • Radiation Oncology Journal
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    • v.19 no.3
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    • pp.230-236
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    • 2001
  • Purpose : To evaluate treatment results in terms of local control, complications and survival after reirraidiation in recurrent cervical cancer following definite radiation therapy. Material and methods : From November 1987 through March 1998, eighteen patients with recurrent cervical cancer following definite radiation therapy were subsequently treated with reirradiation at Keimyung University Dongsan Medical Center. In regard to the initial FIGO stage, one patient was stage la, five were stage IIa, three were IIb, two were IIb and two were IVa. The age range was 37 to 79 years old with median age of 57. The time interval from initial definite radiation therapy to recurrence ranged from 6 to 122 months with a median of 58 months. The recurrent sites were the uterine cervix in seven patients, vagina in ten and pelvic lymph node in one. Reirradiation was peformed with external radiation and intracavitary radiation in twelve patients, external radiation and implantation in four and external radiation alone in two. The range of external radiation dose was $2,100\~5,400\;cGy$ and the range of the total radiation dose was $3,780\~8,550\;cGy$. The follow-up periods ranged from 8 to 20 months with median of 25 following reirradiation. Results : Fourteen of eighteen patients $(78\%)$ had local control just after reirradiation. The two year disease free survival (2YDFS) rate was $53.6\%$. There were statistically significant differences in the 2YDFS according to both recurrent site (2YDFS $28.5\%$ in uterine cervix, $71.4\%$ in vagina, (p=0.03)) and the total dose (2YDFS $71.8\%$ in >6,000 cGy , $25\%$ in $\leq6,000$ cGy, p=0.007). Seven of ten patients who were followed for more than 20 months remain alive and disease free (7/18, $39\%$). Patients treated with external radiation and intracavitary radiation had a higher rate of 2YDFS. Seven patients including 4 patients with no local control experienced local failure in the uterus or vagina and two patients died with distant metastasis. Complications included rectal bleeding in 3 patients, bowel obstruction treated with surgery in two, hematuria in one, radiation cystitis in two, soft tissue swelling in two and vaginal necrosis spontaneously healed in one. There was no statistical difference in complications according to the total dose or the time to recurrence from initial radiation. Conclusion : In patients with recurrence following definite radiation therapy in the uterine cervical cancer, reirradiation may be effective but requires an effort to reduce radiation induced severe complications.

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Comparison of the Agronomic Characteristics of Perilla (Perilla ocimoides L.) Collected from Korean and Chinese Jilim Province (한국과 중국 길림성 재래종 들깨의 작물학적 특성 비교)

  • Kim In-Jae;Kim Min-Ja;Lee Cheol-Hee;Yun Tae;Park Sung-Gue;Lee Woo-Young;Nam Sang-Young
    • Korean Journal of Plant Resources
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    • v.18 no.1
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    • pp.179-185
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    • 2005
  • This study was conducted to evaluate the major agronomic characteristics Korean of 85 and Chinese Jilim Province of 5 local varieties of perilla at Chungbuk Agricultural Research and Extension Services in 2001. Perilla accessions examined were classified into three maturity groups, i.e, early, medium, and late maturity group of $19\;(23\%),\;57\;(67\%)$, and $9\;(10\%)$ accessions, respectively. The early and late maturity groups mainly consisted of collections from middle-northern area and southern area, respectively, while the medium group consisted of accessions from all over the country. But chinese Jilim collection wad all mediumgroup. Average 1,000-seed weight(TSW) was 2.7 g. TSW of the collection from Hamyang was the greatest a 3.9g, while the TSW of Pyungchang collection was the smallest as 1.7g, and most of collections produced medium and small seeds. Perilla accessions with greate 1,000-seed weight seemed to be belonged to the late maturity group. Chinese collection was 2.2 to 3.19g and overage was 2.6g in average. Accodingly TSW hadn't more variegation than Korean. Seed coat colors of gorilla accessions were dark brown$(30\%)$, brown$(55\%)$ and gray brown$(6\%)$, respectively. Among seed coat colors, brown color consisted of $91\%$. Chinese was dark brown$(20\%)$, brown$(80\%)$ in color. Positively correlated that stem height, the number of nodes, branches and flower clusters with Korean and Chinese collection, capsules per flower cluster and the length of flower cluster with Korean collection and 1,000-seed weight and maturing period, flower clusters, stem height and the number of nodes with Chinese collection. And negatively correlated that the number of capsules per flower cluster and 1,000-seed weight with Korean collection and the length of flower cluster, stem height, branches, the number of nodes and flower clusters with Chinese collection.

Recent sharing study results of ITU-R Study Group 7

  • Chung, HyunSoo;Moon, Jun-Cheol;YU, Dai-Hyuk;Je, Do-Heung;Jo, Jung-Hyun;Roh, Duk-Gyoo;Oh, Se-Jin;Sohn, Bong-Won;Lee, SangSung;Kim, Hyo-Ryung
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.2
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    • pp.65.2-66
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    • 2016
  • 국제전기통신연합(ITU)는 지구상의 인류가 사용하는 전파의 공정한 사용과 국가별 분쟁조정을 위한 각종 회의를 주재하는 UN산하의 국제기관으로 현재 200 여 회원국이 참여하고 있다. 그리고 이를 위한 국제법 제정과 각종 연구결과와 기술문서 작성, 사전의견조율 등은 세계전파통신회의(WRC) 및 ITU산하의 관련 연구그룹(SG7)과 작업반(WP7D)에서 이루어진다. 따라서 기존에 제정된 ITU의 각종 기술문서(권고서, 보고서 등) 또는 의제 관련 연구결과를 WRC 의제 특성에 맞도록 결과를 도출하는 작업은 향후의 국제법 제정에 있어서 매우 중요한 변수로 작용한다. 이에 우리나라의 관련 주관청(미래부 전파정책국)에서는 매년 2회 개최되는 ITU-R 연구그룹회의에 정부 대표단을 파견하여, 과학업무(전파천문, 기상, 과학위성 등)와 관련된 기술문서 개정과 WRC의제 연구동향을 주시하면서 우리나라 이익과 관련된 사항에 대한 의견개진을 추진하고 있다. 특히 2019년 및 2023년에 개최되는 WRC-19, 23회의 의제를 위해, 태양활동의 감시, 원활한 기상위성운영, 80-1,000GHz 대역의 전파천문 보호 등에 대한 연구가 관련 연구그룹(SG7)에서 본격화되고 있으며, 이에 대한 지속적인 동향분석과 국내의 입장정리 또는 관련 ITU 기술문서에 대한 정부차원의 적절한 대응정책이 필요하다. 따라서 본 발표에서는 WRC-19 및 WRC-23의제와 관련하여 2016년 4월 5-8일에 스위스 제네바에서 진행되었던 ITU-R 제7연구반 산하작업반별 회의의 공유연구와 주요 결과를 소개하고, 향후 우리나라의 입장, 대응방안 등에 대해 알아보고자 한다.

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Management and role of Baekdudaegan National Arboretum Seed Vault in readiness for unification (통일대비 국립백두대간수목원 시드볼트의 운영과 역할)

  • Bae, Kee Hwa
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.04a
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    • pp.20-20
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    • 2019
  • 전 지구적으로 학명이 보고된 식물 종은 약 36만종이다. 그 중 종자를 생산하는 관속식물은 310,422종으로 전체 식물종의 85.7%에 달한다(IUCN, 2018). 그리고 2015년 Primely Forest Organization (PFO)에서는 야생식물의 80%가 산림 내에 서식한다고 밝혔다. 식물이 인류에게 주는 다양한 이로움은 인류의 생존과 복지증진에 막대한 영향을 미친다. 2016년 State Worlds Plants (SWP)에 따르면 인류가 현재까지 이용하는 식물종은 31,128종으로 알려져 있다. 이중 약용으로 17,810종, 식량으로 5,538종을 유용하게 이용하고 있다. 하지만 현재 전 지구적 생물멸종속도는 산업혁명 이전 보다 약 1,000배정도 빠르게 진행이 되고 있다(Science, 2017). 이에 전 지구적 생물다양성보전을 위해 생물다양성 협약, 지구식물보전전략 등이 지속적으로 발효 이행되고 있다. 시드볼트는 이러한 보전전략을 이행하기 위해 적합한 시설이다. 우리나라도 노르웨이와 전 세계적으로 2곳뿐이 없는 시드볼트를 가지게 되었다. 우리의 시드볼트는 전 지구적 재난과 재앙에 대비해 야생식물종자를 안전하게 영구 저장하는 시설이고, 우리나라는 봉화군에 위치한 국립백두대간수목원 내에 200만점 저장 규모로 조성이 되어 있다. 현재 국내 외 수집 수탁종자 48,327점이 안전하게 저장이 되어 있다. 국내 23개 종자관련 기관, 단체, 개인과 카자흐스탄 등 해외 3개국 6개 기관이 야생식물종자의 영구저장을 요청하였다. 앞으로 시드볼트는 통일시대에 대비하여 지구적 야생식물종자 저장의 컨트롤타워 역할과 종자연구의 중심기관으로 발돋움 할 것이다. 이에 따른 목표로 2050년까지 백두대간 글로벌시드볼트(BGSV)는 전세계 식물종의 13%, 40만점을 저장할 것이다. 특히 종자연구부분에서는 현재 종 맞춤형 활력검정시스템개발, 분류군별 장기저장 특성분석, 장기저장 종자수명예측 등을 고도화하여 한반도 야생식물 종자정보 플랫폼 구축, 고대 매장종자 보전 모델링 연구, 지구 종자연구 브릿지 구축 등으로 개발, 발전시킬 것이다.

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Authentication Test of Archaeological Materials using Single Grain Regenerative Dose Method (단일입자재현법(單一粒子再現法)을 활용한 고고유물의 진위판별 연구)

  • Kim, Myung-Jin;Youn, Min-Young;Hong, Duk-Geun
    • Journal of Conservation Science
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    • v.23
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    • pp.73-80
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    • 2008
  • This article aims to turn out the authentication of archaeological materials by using the paleodose measurement to fine sand-size quartz grains obtained by micro sampling technique. We firstly revealed the validity of micro sampling technique from the paleodoses of two bricks related to Muryong Royal Tomb of Baekje Kingdom. For the purpose of authentication test, four archaeological materials were selected, because they have been insisted that they were manufactured in Goguryeo Kingdom era. After obtaining very few quartz grains by micro sampling technique, each paleodose was evaluated by using SGR (single grain regenerative dose method). All values were very low below 0.2Gy and the reliability was found from those values by using SAR (single aliquot regenerative dose method). Considering the archaeological situation and the general paleodose, the burial time for 1,000 years generally corresponds to about 3.5Gy in Korea, it is concluded that these archaeological materials are all modern counterfeits.

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