• Title/Summary/Keyword: 유사성 탐색

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The Comparative Imaging Study on Mn-phthalocyanine and Mangafodipir trisodium in Experimental VX2 Animal Model (실험적으로 유발시킨 VX2 동물모델에서의 Mn-phthalocyanine과 Mangafodipir trisodium의 비교영상)

  • Park Hyun-Jeong;Ko Sung-Min;Kim Yong-Sun;Chang Yongmin
    • Investigative Magnetic Resonance Imaging
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    • v.8 no.1
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    • pp.32-41
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    • 2004
  • Purpose : To measure the NMR relaxation properties of MnPC, to observe the characteristics of liver enhancement patterns on MR images in experimentally implanted rabbit VX2 tumor model, and to estimate the possibility of tissue specific contrast agent for MnPC in comparison with the hepatobiliary agent. Materials and Methods : Phthalocyanine (PC) was chelated with paramagnetic ions, manganese (Mn). 2.01 g (5.2 mmol) of phthalocyanine was mixed with 0.37 g (1.4 nlmol) of Mn chloride at $310^{\circ}C$ for 36 hours and then purified by chromatography ($CHCl_3:\;CH_3OH=98:2$, volume ratio) to obtain 1.04 g $(46\%)$ of MnPC (molecular weight = 2000 daltons). The T1/T2 relaxivity (R1/R2) for MnPC were determined at a 1.5 T (64 MHz) MR spectrometer. VX2 tumor model was experimentally implanted in the liver parenchyma of rabbits. All MR studies were performed on 1.5 T. The human extremity radio frequency coil of a bird cage type was employed. MR images were acquired at 17 to 24 days after VX2 carcinoma implantation.4 mmol/kg MnPC and 0.01 mmol/kg Mn-DPDP were injected via the ear vein of rabbits. T1-weighted images were obtained with spin-echo (TR/TE=516/14 msec) and fast multiplanar spoiled gradient recalled (TR/TE : 80/4 msec, $60^{\circ}$ flip angle) pulse sequence. Fast spin-echo (TR/TE=1200/85 msec) was used to obtain the T2-weighted images. Results : The value of T1/T2 relaxivity (R1/R2) of MnPC was $7.28\;mM^{-1}S^{-1}$ and $55.56\;mM^{-1}S^{-1}$ respectively at 1.5 T (64 MHz). Because the T2 relaxivity of MnPC that bonded strongly, covalently manganese with phthalocyanine was very high, the signal intensity of liver parenchyma was decreased on postcontrast T2-weighted images and we could easily distinguish the VX2 carcinoma within the liver parenchyma. When MnPC was administrated intravenously, the tumor margin delineation was more remarkable than Mn-DPDP-enhanced images. The enhancement of liver parenchyma with MnPC persisted at relatively high levels over at least one hour after injection of the contrast agents. Conclusion : The hepatic uptake and biliary excretion of MnPC, which are similar to Mn-DPDP, suggest that this agent is a new liver-specific agent. Also, MnPC seems to be used as a dual contrast agent (T1 and T2) with high T2 relaxivity. However, it is warranted that MnPC needs further investigation as a potential contrast agent for MR imaging of the liver. That is, further characterizations of MnPC are needed in vivo and in vitro before clinical trials. The diagnostic potential of MnPC will also have to be examined more in the animal models of additional types.

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Antibacterial Effect of Fermented Rice Water against Food-borne Bacteria in Kitchen Towel (행주 내 식품위해미생물에 대한 쌀뜨물 발효액의 살균 효과)

  • Ha, Ji-Hyoung;Lee, Yu-Si;Lee, Seok-Joo;Hwang, Sun-Soon;Ha, Sang-Do
    • Journal of Food Hygiene and Safety
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    • v.22 no.4
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    • pp.365-369
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    • 2007
  • This study was conducted to seek optimum concentration and treatment time of fermented rice water (Rizen) to disinfect food-borne bacteria in kitchen towel. $2.65\;log_{10}cfu/g$ of E. coli was reduced when double or triple diluted fermented rice water was treated during 2 hours. In case of concentrated fermented rice water, crude and double diluted solutions showed complete sterilization after 2 and 5 hours, respectively. On the other hand, triple, quadruple, quintuple diluted solutions needed 24 hours for complete sterilization. The effect of fermented rice water as a disinfectant was compared with water, detergent and chlorine treatment against E. coli and S. Typhimurium contaminated in kitchen towel. The initial number of E. coli in untreated kitchen towel were $5.0\;log_{10}cfu/g$ and were decreased to 4.32, 3.70 and 3.02 by treatments of water, detergent and chlorine, respectively. The double and triple diluted fermented rice water and double diluted concentrated fermented rice water also reduced the E. coli in kitchen towel to 2.43, 2.30 and $1.88\;log_{10}cfu/g$, respectively. The initial number of S. Typhimurium in untreated kitchen towel were $4.80\;log_{10}cfu/g$ and were decreased to 4.12, 3.58 and 2.81 by treatments of water, detergent and chlorine, respectively. The double and triple diluted fermented rice water and double diluted concentrated fermented rice water also reduced the E. coli in kitchen towel to 2.14, 2.03 and $1.59\;log_{10}cfu/g$, respectively. Consequently, the fermented rice water is thought to be a good disinfectant to reduce food-borne bacteria like E. coli and Salmonella contaminated in kitchen towel.

A Study for the Certified Security Certification in Private Security Industry in Korea (민간경비 자격제도에 관한 연구)

  • Ahn, Hwang-Kwon
    • Korean Security Journal
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    • no.11
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    • pp.159-181
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    • 2006
  • This study is concerned on Why The Certified Security certification is needed and How to control the security quality to get better service to the clients. Theses days are required The Certified Certificate in all the industry. And in this point of view, the certified certificate is a kind of confirmation by an authority to the person who has how much special knowledge and practice in a certain field. Moreover, in the functionalism society the certified certificate system would be very positive effect to the related industry and society as official measurement by an authority. The security is freedom from fear and anxiety. Which means the security can not be operated in isolation from citizen's safe-living expectation, and which is also dealing with valuable human being's life. For getting the better purpose the security industry employees should have more organized special training and education. As my understanding the certified certificate exam system is the confirmation by an authority, the certified certificate is only neutral evidence to get the confidence and credit from the clients. In this point of view the core point is How to control The Certified Certificate by a credied authority.

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Anti-Diabetic, Alcohol-Metabolizing, and Hepatoprotective Activities of Moringa (Moringa oleifera Lam.) Leaf Extracts (모링가 잎 추출물의 항당뇨, 알코올 대사 및 간 보호 활성)

  • Choi, Young Ju;Jung, Kyung Im
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.6
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    • pp.819-827
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    • 2016
  • This study was carried out to investigate anti-inflammatory, anti-diabetic, alcohol metabolizing, and hepatoprotective effects of hot water (MOW) and 80% ethanol (MOE) extracts from moringa (Moringa oleifera Lam.) leaf. The total phenol content of MOW and MOE were 45.49 and 63.06 mg tannic acid equivalents/g, respectively. 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activities of MOW and MOE were remarkably elevated in a dose-dependent manner, and about 60.8% and 71.3% at 1 mg/mL, respectively (P<0.01). Superoxide dismutase-like activities of MOW and MOE were 2.8% and 7.4% at 5 mg/mL, respectively (P<0.05). ${\alpha}-Glucosidase$ inhibitory activity also increased in a dose-dependent manner in both extracts, and MOE was higher about two times than MOW at 5 mg/mL (P<0.001). The effects of MOW and MOE on alcohol metabolizing activity were determined by measuring generation of reduced nicotinamide adenine dinucleotide (NADH) by alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH). ADH and ALDH activities significantly increased upon addition of MOW and MOE (P<0.05). Anti-inflammatory activity was examined in lipopolysaccharide-stimulated RAW 264.7 cells. Nitric oxide production was reduced to 32.1% and 81.2% by addition of MOW and MOE at 1 mg/mL, respectively (P<0.05). MOW and MOE showed significant protective effects against tacrine-induced cytotoxicity in Hep3B cells at $100{\mu}g/mL$. These results suggest that moringa leaf extracts have great potential as natural health products.

Expression profile of defense-related genes in response to gamma radiation stress (방사선 스트레스 반응 방어 유전자의 탐색 및 발현 분석)

  • Park, Nuri;Ha, Hye-Jeong;Subburaj, Saminathan;Choi, Seo-Hee;Jeon, Yongsam;Jin, Yong-Tae;Tu, Luhua;Kumari, Shipra;Lee, Geung-Joo
    • Journal of Plant Biotechnology
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    • v.43 no.3
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    • pp.359-366
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    • 2016
  • Tradescantia is a perennial plant in the family of Commelinaceae. It is known to be sensitive to radiation. In this study, Tradescantia BNL 4430 was irradiated with gamma radiation at doses of 50 to 1,000 mGy in a phytotron equipped with a $^{60}Co$ radiation source at Korea Atomic Energy Research Institute, Korea. At 13 days after irradiation, we extracted RNA from irradiated floral tissues for RNA-seq. Transcriptome assembly produced a total of 77, 326 unique transcripts. In plantlets exposed to 50, 250, 500, and 1000 mGy, the numbers of up-regulated genes with more than 2-fold of expression compared that in the control were 116, 222, 246, and 308, respectively. Most of the up-regulated genes induced by 50 mGy were heat shock proteins (HSPs) such as HSP 70, indicating that protein misfolding, aggregation, and translocation might have occurred during radiation stress. Similarly, highly up-regulated transcripts of the IQ-domain 6 were induced by 250 mGy, KAR-UP oxidoreductase 1 was induced by 500 mGy, and zinc transporter 1 precursor was induced by 1000 mGy. Reverse transcriptase (RT) PCR and quantitative real time PCR (qRT-PCR) further validated the increased mRNA expression levels of selected genes, consistent with DEG analysis results. However, 2.3 to 97- fold higher expression activities were induced by different doses of radiation based on qRT-PCR results. Results on the transcriptome of Tradescantia in response to radiation might provide unique identifiers to develop in situ monitoring kit for measuring radiation exposure around radiation facilities.

Screening of Lignan Compounds and Antioxidant Activity of Chungkukjang Fermented with Defatted Sesame Flour (참깨 탈지박을 첨가하여 제조한 청국장의 생리활성 및 리그난 성분 탐색)

  • Kim, Tae-Su;Choi, Mi-Kyeong;Kim, Jin-Sook;Han, Jae-Woong;Kang, Myung-Hwa
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.11
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    • pp.1580-1586
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    • 2009
  • This study is on the effect of oil seed by-products added to Chungkukjang. For this, we designed three cases: Chungkukjang was added in with defatted sesame flour before fermented (DSFBF), added with defatted sesame flour after fermented (DSFAF) and with no adding (control). In each case, the common ingredients and the active antioxidant ingredients were examined and compared and the effects were analyzed. According to microanalysis result, carbohydrate content Chungkukjang the DSFAF 24.97%, control 23.86%, DSFBF Chungkukjang 20.21% as compared to control and Chungkukjang DSFAF relatively low carbohydrate content. The moisture contents in DSFBF (55.98%) or DSFAF (52.83%) were higher than that in control (48.89%). Chungkukjang crude ashes in DSFBF (1.48%) or DSFAF (2.41%) were much lower than in control (6.45%). The proportions of crude lipid in DSFBF (3.30%) or DSFAF (3.93%) were higher than in control (1.77%) by about 2%. As for crude protein, the percentage in DSFAF (15.86%) was lower than that of DSFBF (19.03%) or of control (19.03%). There was no meaningful difference in biological activity measurement as total phenolic contents were 1.26 mg/mL in DSFBF, 1.14 mg/mL in DSFAF and 1.26 mg/mL in control. But electron donating ability was meaningfully more active in DSFBF (21.30%) than in control (20.24%). The superoxide dismutase (SOD)-like activity in DSFBF (68.48%) was twice higher than in control (34.01%), which may imply that DSFBF contain some ingredients that can scavenge superoxide anion radically. In hydroxyl radical scavenging activity, DSFAF scores 96.87%, which is the highest with 96.40% in DSFBF and 95.73% in control. Relative antioxidative effects in DSFBF was 47.92%, which is comparable to 47.06% in control. As a result of extraction and quantitative HPLC analysis of sesamin and sesamolin extracted from the samples, DSFBF contained 3.04$\pm$0.21 mg/g of sesamin, which is meaningfully higher than 2.41$\pm$0.14 mg/g in DSFAF. Content of sesamolin was higher in DSFBF (1.36$\pm$0.09 mg/g) than DSFAF (1.12$\pm$0.07 mg/g) or in control. We can conclude that biologically active and effective ingredients could be found more in DSFBF than in DSFAF or in control. This study conveys not only the meaning that oil seed by-products can be used as an ingredient for making Chungkukjang functional food, but also the possibility that oil seed by-products themselves could become excellent functional food.

A Study on the Formation Process and the Settling Period of the Gwandong-Palkyung by the Thematic Exploration of Joseon Landscape Poetry and Paintings (옛 시문과 그림으로 살핀 관동팔경(關東八景)의 형상화 및 정착시기)

  • Rho, Jae-Hyun;Son, Hee-Kyung
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.1
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    • pp.10-24
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    • 2017
  • The research takes note of the formation process and settling period of Gwandong-Palkyung(關東八景, Eight Sites of Eastern Korea), the representative palgyeong(prominent eight sites) and jipgyeong(集景, landscape collection of scenic beauty), and investigates the time of formation regarding the palkyung and jipgeyong of Gwandong's scenic beauty through the analysis and interpretation of bibliographic data, and reference data. The result of the study is as follows. As the first document that records the terminology of "Gwandong-Palkyung" is "Daphongeunggil(答洪應吉)" of Yi, Hwang(李滉), Gwandong-Palkyung is inferred to be settled within the recognition of the people even before the 16th century. The geographic analysis result including "Sinjeung Donggukyeojiseungram(新增東國輿地勝覽)", Gwandong-Palkyung expanded as Gwandong-Sipkyung in early to middle of the 16th century. The first confirmed landscape collection regarding Gwandong-Palkyung in this study is confirmed in Shin Zup(申楫)'s "Yeonggwandong-Palkyung(詠關東八景)", thus, the terminology of Gwandong-Palkyung existed before 16th century at the latest. The settlement time of current "Palkyung" collection is estimated to be early 17th century at the latest. Poetries regarding Gwandong-Palkyung, and the frequency on the appearance of Gwandong scenic beauties are analyzed as making clear of the concentrated phenomenon on the sceneries of Gwandong-Palkyung. On the other hand, the collection of Gwandong-Palkyung in the domain of arts is confirmed initially in the ${\ll}$Gwandongpalkyungdobyeong(關東八景圖屛)${\gg}$ of Heo, Pil(許泌). Gwandong-Palkyung, expressed as the actual scene landscape painting shows similar tendencies of the conditions in the jipgyeong from the poetry, but the appearance rate of the painting subject was more prominent in visual solidarity and cohesion due to the reflection of the importance on icon(圖像) of the art works produced with particular meaning in the case of fixed ideal system. From late Joseon to modern times, ${\ll}$palpokbyeongpung(八幅屛風)${\gg}$ of various forms of folk painting is a corroborative evidence notifying that the cultural phenomenon of Gwandong-Palkyung has entered the universal period of embrace. Also, the 13 scenic beauties of Gangwon-Do appearing in the games of Namseungdo and Myeongseungyuramdo include Gwandong-Palkyung, which confirms the settlement of Gwandog-Palkyung even within the culture of games in late Joseon. Such results demonstrate the existence of awareness regarding Gwandong-Palkyung from the first half of the 15th century, which is presumed to have completely settled in the 17th century through the continuous development of formative process in the 16th century. Ultimately, Gwandong-Palkyung is the concrete formation of regional scenic beauties that individually gained its reputations as scenery from the Koryo Dynasty to late 17th century. Gwandong-Palkyung of the scenic beauty of Gwandong is a unique cultural scenery of the region that have germinated and formed through the process of cutting and polishing of long time to collect the best eight of scenic beauty from the many participation of sightseeing culture.

Development of Customer Sentiment Pattern Map for Webtoon Content Recommendation (웹툰 콘텐츠 추천을 위한 소비자 감성 패턴 맵 개발)

  • Lee, Junsik;Park, Do-Hyung
    • Journal of Intelligence and Information Systems
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    • v.25 no.4
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    • pp.67-88
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    • 2019
  • Webtoon is a Korean-style digital comics platform that distributes comics content produced using the characteristic elements of the Internet in a form that can be consumed online. With the recent rapid growth of the webtoon industry and the exponential increase in the supply of webtoon content, the need for effective webtoon content recommendation measures is growing. Webtoons are digital content products that combine pictorial, literary and digital elements. Therefore, webtoons stimulate consumer sentiment by making readers have fun and engaging and empathizing with the situations in which webtoons are produced. In this context, it can be expected that the sentiment that webtoons evoke to consumers will serve as an important criterion for consumers' choice of webtoons. However, there is a lack of research to improve webtoons' recommendation performance by utilizing consumer sentiment. This study is aimed at developing consumer sentiment pattern maps that can support effective recommendations of webtoon content, focusing on consumer sentiments that have not been fully discussed previously. Metadata and consumer sentiments data were collected for 200 works serviced on the Korean webtoon platform 'Naver Webtoon' to conduct this study. 488 sentiment terms were collected for 127 works, excluding those that did not meet the purpose of the analysis. Next, similar or duplicate terms were combined or abstracted in accordance with the bottom-up approach. As a result, we have built webtoons specialized sentiment-index, which are reduced to a total of 63 emotive adjectives. By performing exploratory factor analysis on the constructed sentiment-index, we have derived three important dimensions for classifying webtoon types. The exploratory factor analysis was performed through the Principal Component Analysis (PCA) using varimax factor rotation. The three dimensions were named 'Immersion', 'Touch' and 'Irritant' respectively. Based on this, K-Means clustering was performed and the entire webtoons were classified into four types. Each type was named 'Snack', 'Drama', 'Irritant', and 'Romance'. For each type of webtoon, we wrote webtoon-sentiment 2-Mode network graphs and looked at the characteristics of the sentiment pattern appearing for each type. In addition, through profiling analysis, we were able to derive meaningful strategic implications for each type of webtoon. First, The 'Snack' cluster is a collection of webtoons that are fast-paced and highly entertaining. Many consumers are interested in these webtoons, but they don't rate them well. Also, consumers mostly use simple expressions of sentiment when talking about these webtoons. Webtoons belonging to 'Snack' are expected to appeal to modern people who want to consume content easily and quickly during short travel time, such as commuting time. Secondly, webtoons belonging to 'Drama' are expected to evoke realistic and everyday sentiments rather than exaggerated and light comic ones. When consumers talk about webtoons belonging to a 'Drama' cluster in online, they are found to express a variety of sentiments. It is appropriate to establish an OSMU(One source multi-use) strategy to extend these webtoons to other content such as movies and TV series. Third, the sentiment pattern map of 'Irritant' shows the sentiments that discourage customer interest by stimulating discomfort. Webtoons that evoke these sentiments are hard to get public attention. Artists should pay attention to these sentiments that cause inconvenience to consumers in creating webtoons. Finally, Webtoons belonging to 'Romance' do not evoke a variety of consumer sentiments, but they are interpreted as touching consumers. They are expected to be consumed as 'healing content' targeted at consumers with high levels of stress or mental fatigue in their lives. The results of this study are meaningful in that it identifies the applicability of consumer sentiment in the areas of recommendation and classification of webtoons, and provides guidelines to help members of webtoons' ecosystem better understand consumers and formulate strategies.

A Proposal to Control System and the Problems of the Problems of the Report about Supply and Demand for Medical Technicians and Management Policy ("의료기사인력수급에 관한 보고서"의 문제점과 관리제도의 개선방안)

  • Kim, Sang-Hyun;Lim, Yongmoo
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.4
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    • pp.25-30
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    • 2008
  • Purpose: In this paper, we have analyzed the problems of the Oh's report which is used to the basic data for supply and demand of medical technicians and studied a proposal for improvement to control system and supply and demand of korean optometrists. Methods: We have analyzed errors of Oh's report including supply and demand for medical technicians and management policy, expecting number for future optician, inaccurate estimation by limited data (employment rate, retirement rate, mortality rate) and an incorrect method of measurement for future supply and demand. Results: Oh's report showed the 18% error for estimation of supply which exclude the irregular entrance students. The estimation of supply was calculated by graduation rate 62.6% (college and University of Technology are 78.9% and 85.98% respectively), employment rate 65.8% (the average employment between 2002 and 2007 is 73.96%) and retirement rate is 2.3% (the retirement of pharmacists is 1.3%) but it showed the significant differences to objective data. For estimate the suitable ratio of optometrists to the population, the ratio use of medical facilities by an age group was used, and suggested spectacle wearers 1,280 persons (populations 2,928 persons) per optometrist but the different from reference of Germany (4,706 persons), America (1,789 persons) and Korea (1,825 persons/an optometrist) are applied to estimation on supply. This report applied the low employment rate and argued that maintain the present situation, but claimed that utilize unemployment persons. The above result has induced double weighting effect on estimation of supply. Conclusions: To solve the related problems of supply and demand, we have to make a search for exact data and optimum application model, have to take an example of nation similar job category as Germany and the research result of the job satisfaction into consideration. After we get the integrated research result, we must carried out the policy with fairness and balance for the estimation of supply and demand. Therefore exact research is required prior to beginning policy establishment, government and related group have to make a clear long-term plan and permanent organization for medical technician to establish supply and demand of medical technician.

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Site Characteristics, and Vegetation Structure, and Dynamics of Forest Communities growing Kalopanax septemlobus (Thunb.ex Murray) Koidz. in Gangwon-do (강원도 음나무 자생 임분의 입지환경, 식생구조 및 동태)

  • 이철호;최영철;김세현;권기원
    • Korean Journal of Plant Resources
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    • v.13 no.3
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    • pp.227-242
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    • 2000
  • Site characteristics, vegetation structure and dynamics of Kalopanax septemlobus forests in Mt. Heungjeong, Mt. Balwang and Mt. Gariwang were studied to provide the information need for national resources conservation and restoration of K. septemlobus forest in Gangwon-do of Korea. The K. septemlobus forests were distributed at 780m to 1,300m in altitude, steep slope, ridges-slope areas with facing northeast to northwest in good nutrition area. The annual diameter growth of those trees ranged 1.60mm to 2.41mm. Forty-three plots(20$\times$20m) were set up at three natural population of Kalopanax septemlobus forest and TWINSPAN method was used for vegetation structure analysis. The result of TWINSPAN ordination show that geographical features played a role in determining community types in the study areas. Community type of the study areas classified into three groups by TWINSPAN; K. septemlobus-Quercux mongolica- Acer mono community(Mt. Balwang), K. septemlobus-Q. mongolica- Tilia amurensis community(Mt. Heungjeong), K. septemlobus-Betula costata-Q. mongolica community(Mt. Gariwang). In most of the K. septemlobus forests, major woody species appeared predominantly were Q. mongolica, T. amurensis, Acer pseudo-sieboldianum, Lindera obtusiloba, A. mono, Magnolia sieboldii, Ulmus davidiana var. japonica. And also, Those species were surveyed in all the areas. Species diversity(H') of investigated areas ranged 0.3124~0.13992 and this value relatively higher than that of other forests with similar site. The range of similarity indices between surveyed areas was 64.1~64.54%. The distribution pattern of Morista's index show that Kalopanax septemlobus distributed randomly in tree and concentrated a few sample plots in subtree layer and shurb layer. K. septemlobus occupied 37.1~58.8% of tree layer story, 8.4~17.6% of subtree layer, 0~0.38% of shurb layer each surveyed area. The association analysis showed that Kalopanax septemlobus positively associated with Betula ermani, Deutzia glabrata, Carpinus cordata, Fraxinus mandshurica and negatively associated with Symplocos chinensis var. pilosa, Styrax obassia, Acer mono, Euonymus macroptera, Ulmus davidiana var. japonica. According to the diameter distribution of Kalopanax septemlobus community, the community of Mt. Gariwang will gradually decline and replaced by Quercus community. The communities of Mt. Heungjeong and Mt. Balwang has its seedlings and saplings, so it may be sustained.

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