• 제목/요약/키워드: Open

Search Result 25,756, Processing Time 0.059 seconds

Environmental Change of High Moor in Mt. Dae-Am of Korean Peninsula (대암산 고층습원의 환경변천)

  • Yoshioka, Takahito;Kang, Sang-Joon
    • Korean Journal of Ecology and Environment
    • /
    • v.38 no.1 s.110
    • /
    • pp.45-53
    • /
    • 2005
  • The environmental change of Yong-nup in Mt. Dae-Am, which is located at the northern part of Kangwon-Do, Korea, was assesed with peat sedimentary carbon and nitrogen isotope analysis. The surface layer of the peat (0 ${\sim}$ 5 cm) was 190 year BP, and the middle layers (30 ${\sim}$ 35 cm and 50 ${\sim}$ 55 cm) were 870 year BP and 1900 year BP, respectively. Bulk sedimentation rate was estimated to be about 0.4 mm $year^{-1}$ for 0 cm to 30 cm and 0.15 mm $year^{-1}$ for 35 cm to 50 cm. The $^{14}C$ age of the bottom sediment (75 ${\sim}$ 80 cm) collected and measured in this study was about 1900 year BP, although it was measured that the $^{14}C$ of the lowest bottom sediment in Yong-nup was 4105 ${\pm}$ 175 year BP (GX-23200). Since the $^{14}C$ ages for 50 ${\sim}$ 55 cm and 75 ${\sim}$ 80 cm layers were almost the same as 1890 ${\pm}$ 80 fear BP (NUTA 5364) and 1850 ${\pm}$ 90 year BP (NUTA 5462), respectively, we have estimated that the deep layers (55 ${\sim}$ 80 cm) in the high moor were the original forest soil. The low organic C and N contents in the deeper layers supported the inference. The sediment of 50 ${\sim}$ 55 cm layer contains much sandy material and showed very low organic content, suggesting the erosion (flooding) from the surrounding area. In this context, the Yong-nup, high moor, of Mt. Dae-Am, might have developed to the sampling site at about 1900 year BP. The ${\delta}^{13}C$ values of organic carbon and the ${\delta}^{15}N$ values of total nitrogen in the peat sediments fluctuated with the depths. The profile of ${\delta}^{13}C$ may indicate that the Yong-nup of Mt. Dae-Am have experienced the dry-wet and cool-warm period cycles during the development of the high moor. The ${\delta}^{15}N$ may indicate that the nitrogen cycling in the Yong-nup have changed from the closed (regeneration depending) system to the open (rain $NO_3\;^-$ and $N_2$ fixation depending) system during the development of the high moor.

Study on Conservation and Habitat Restoration Based on Ecological Diagnosis for Cymbidium kanran Makino in Jeju Island, Korea (한국 제주도 한란의 생태 진단에 기초한 보전 및 서식지 복원에 관한 연구)

  • Jung, Ji-Young;Shin, Jae-Kwon;Kim, Han-Gyeoul;Byun, Jun-Gi;Pi, Jung-Hun;Koo, Bon-Yeol;Park, Jeong-Geun;Suh, Gang-Uk;Lee, Cheul-Ho;Son, Sung-Won;Kim, Jun-Soo;Cho, Hyun-Je;Bae, Kwan-Ho;Oh, Seung-Hwan;Kim, Hyun-Cheol;Kang, Seung-Tae;Cho, Yong-Chan
    • Korean Journal of Ecology and Environment
    • /
    • v.49 no.1
    • /
    • pp.11-21
    • /
    • 2016
  • Cymbidium kanran Makino is being threatened in its own habitats due illegal collecting and habitat changes by vegetation growth along historical landuse change. In this study, we established habitat restoration model for conservation of C. kanran based on ecological diagnosis. Through exploration to Jeju Island in 2014 and 2015, we identified 27 unknown habitats of C. kanran and in there, abiotic variables and vegetation structure and composition were quantified. Altitudinal distribution of C. kanran was between 200 m~700 m a.s.l. and compared to distribution in 2004, Area of Occupation (AOO) decreased at 82%. Specific habitat affinity was not observed by evenly found in mountain slope and valley and summergreen and evergreen broadleaved forests, but likely more abundant in valley habitats with higher soil and ambient moisture. Total of 96 individual of C. kanran was observed with an average density of $942.6individuals\;ha^{-1}$. The plants showed relatively short leaf length (average=$10.7cm{\pm}1.1cm$) and small number of pseudo bulbs ($1.2{\pm}0.2$). Flowering and fruiting individuals were not observed in field. C. kanran was classified into endangered plant species as CR (Critically Endangered) category by IUCN criteria. Phenotypic plasticity of C. kanran was likely support to sustain in more shaded habitat environment and recent habatat changes to closed canopy and low light availability may exhibit negatively effects to C. kanran's life history. Restoring C. kanran habitat should create open environment as grassland and low woody species density.

Studies on the Function of the Rv2435c Gene of the Mycobacterium bovis BCG (Mycobacterium bovis BCG Rv2435c 유전자의 기능에 대한 연구)

  • Lee Seung-Sil;Bae Young-Min
    • Journal of Life Science
    • /
    • v.15 no.3 s.70
    • /
    • pp.415-422
    • /
    • 2005
  • library of the mutants was prepared by transposon mutagenesis of the Mycobacterium bovis BCG. We screened this library for the resistance to an anti-tuberculosis antibiotic, PA-824. Most of the mutants resistant to the PA-824 were not able to synthesize the coenzyme $F_{420}$ which is normally produced by the wild type M. bovis BCG strains. HPLC analysis of the cellular extract showed that one of those mutants which lost the ability to synthesize $F_{420}$ still produced F0. The insertion site of the transposon in this mutant was determined by an inverse PCR and the transposon was found to be inserted in the Rv2435c open reading frame (ORF). Rv2435c ORF is predicted to encode an 80.3 kDa protein. Rv2435c protein appears to be bound to the cytoplasmic membrane, its N-terminal present in the periplasm and C-terminal in the cytoplasm. The C-terminal portion of this protein is highly homologous with the adenylyl cyclases of both prokaryotes and eukaryotes. There are 15 ORFs which have homology with the class III AC proteins in the genome of the M. tuberculosis and M. bovis. Two of those, Rv1625c and Rv2435c, are highly homologous with the mammalian ACs. We cloned the cytoplasmic domain of the Rv2435c ORF and expressed it with six histidine residues attached on its C-terminal in Escherichia coli to find out if this protein is a genuine AC. Production of that protein in E. coli was proved by purifying the histidine-tagged protein by using the Ni-NTA resin. This protein, however, failed to complement the cya mutation in E. coli, indicating that this protein lacks the AC activity. All of the further attempts to convert this protein to a functional AC by a mutagenesis with UV or hydroxylamine, or construction of several different fusion proteins with Rv1625c failed. It is, therefore, possible that Rv2435c protein might affect the conversion of F0 to $F_{420}$ not by synthesizing cAMP but by some other way.

Selection of Growth Characteristics and Yield of Annual Legumes on Paddy Field (논에서 생육특성과 수량이 우수한 두과 사료작물 선발)

  • Kim, Won-Ho;Lee, Joung-Kyong;Park, Hyung-Soo;HwangBo, Soon;Lim, Young-Cheol;Ji, Hee-Chung;Lee, Hyo-Won;Yoon, Bong-Ki;Seo, Sung
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.29 no.4
    • /
    • pp.307-312
    • /
    • 2009
  • This experiment was conducted to compare the agronomic characteristics and productivity of induced annual legumes at paddy field of Cheonan and Naju from 2004 to 2006. Chinese milk vetch (wild type), crimson clover (C.V. Linkarus), forage pea (C.V. Austrian pea), hairy vetch (C.V. Oregon commen) were used in this study. At the Naju region, the earliest flowering on 2nd may was found in Chinese milk vetch, while the latest on 18th May in forage pea. Fresh, dry matter (DM) and crude protein (CP) yields of crimson clover were highest as 28,870, 6,986 and 943 kg/ha, respectively. but the yield of chinese milk vetch was low by 9,885, 1,749 and 338 kg/ha. At the Cheonan region, the most fast flowering date variety was Chinese milk vetch, hairy vetch was very late as 19th May. Fresh, DM and CP yields of hairy vetch were highest as 7,916, 1,141 and 113 kg/ha, respectively. but the yield of chinese milk vetch showed the lowest by 270, 42 and 8 kg/ha. The CP content of annual legumes was 14.3%. chinese milk vetch showed the highest CP content by 19.3% and hairy vetch showed the lowest content by 9.9%. The present data showed that the productivity was closely dependent on winter hardness, in conclusion, crimson clover at Naju and hairy vetch at Cheonan region was suggested to be the most proper species as winter crop after rice harvest on paddy field when considered the winter hardiness.

Selection of Promising Forage Pea Cultivars on Paddy Field (논에서 적응성이 우수한 Forage Pea 품종 선발)

  • Kim, Won-Ho;Lee, Joung-Kyong;Lim, Young-Cheol;Shine, Jae-Soon;Jung, Min-Woong;Ji, Hee-Chung;Seo, Sung;Lee, Hyo-Won;Yoon, Bong-Ki
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.29 no.1
    • /
    • pp.7-12
    • /
    • 2009
  • This experiment was conducted to compare the agronomic characteristics and productivity in introduced forage pea cultivars at the experimental field. The experiment was arranged in a randomized block design with three replications. The forage pea used in this study were two cultivars ('Livioletta', 'Austrian Pea') and one Chinese milk vetch cultivar (Chinese domestic cultivar). Flowing of 'Livioletta' cultivar was May 16th and 'Austrian Pea' cultivar was 18th May, 20 days later than the former. The 'Livioletta' cultlvar showed stronger than winter hardiness of 'Austrian Pea' cultivar. Dry matter (DM) content of 'Liviotetta' and 'Austrian Pea' cultivars were 22.5% and 20.9% chinese milk vetch showed the lowest content with 17.7%. 'Austrian pea' cultivar showed the highest DM yield with 5,617 kg/ha but the DM yield of 'Livioletta' cultivar was low with 3,652 kg/ha. The yield of CP (crude protein) and TDN (total digestible nutrient) set high at 'Austrian Pea' cultivar. And 'Livioletta' and 'Austrian Pea' cultivars showed CP content with 15.5% and 14.4% but Chinese milk vetch with 19.3%. The acid detergent fiber (ADF) and neutral detergent fiber (NDF) content of 'Austrian Pea' cultivar were 23.2% and 40.3%. Therefore 'Austrian pea' cultivar seems to be suitable varieties in paddy field as winter forage crops.

Studies on Hilly Pasture Landscape Expectancy, Satisfaction of Tourist on Grassland Facility: A case Study of Yangtae Farm Visitor (산지목장 방문자의 목장 경관 기대와 목초지 및 초지시설 만족도에 관한 연구 : 양떼목장 방문객의 경우)

  • Kang, Dae-Koo;Lee, Hyo-Jin;Lee, Hyowon
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.37 no.1
    • /
    • pp.68-79
    • /
    • 2017
  • The objective of study was to find the relationship in hilly pasture landscape expectancy and tourist's satisfaction on grassland facility. It was followed by literature reviews and visitors' survey in Daegwallyeong Yangtte Farm on 31, July, 2014. 367 respondents were analyzed by F-test, t-test, Chi-square and Fisher's Exact Test at 0.05 level after data screening process. Computing factors were sex, marital status, age, academic career and occupation. The results was as followed; First, major respondents group of survey were in oder of woman, forty years old group, married office worker, and university graduate. Second, the expectancy for grassland was significant difference in age, but pasture color expectancy was not significant difference in gender, age, educational background, marital status, and there was significant difference in favorite grassland type with age, marital status. Third, favorite fence type was not significant difference along with all group of participants. However, color and material of fence was significant difference in marital status. Fourth, preferred ranch road was significant difference with occupation and marital status. There was significant difference in favorite grassland type near ranch road along with age and occupation type. Fifth, the mean satisfaction was 3.6 point in 5.0. Therefore, all respondents were generally satisfaction in visited. Tourists were more interested in ranch landscape than experience or contacts to animal.

A Performance Comparison of the Mobile Agent Model with the Client-Server Model under Security Conditions (보안 서비스를 고려한 이동 에이전트 모델과 클라이언트-서버 모델의 성능 비교)

  • Han, Seung-Wan;Jeong, Ki-Moon;Park, Seung-Bae;Lim, Hyeong-Seok
    • Journal of KIISE:Information Networking
    • /
    • v.29 no.3
    • /
    • pp.286-298
    • /
    • 2002
  • The Remote Procedure Call(RPC) has been traditionally used for Inter Process Communication(IPC) among precesses in distributed computing environment. As distributed applications have been complicated more and more, the Mobile Agent paradigm for IPC is emerged. Because there are some paradigms for IPC, researches to evaluate and compare the performance of each paradigm are issued recently. But the performance models used in the previous research did not reflect real distributed computing environment correctly, because they did not consider the evacuation elements for providing security services. Since real distributed environment is open, it is very vulnerable to a variety of attacks. In order to execute applications securely in distributed computing environment, security services which protect applications and information against the attacks must be considered. In this paper, we evaluate and compare the performance of the Remote Procedure Call with that of the Mobile Agent in IPC paradigms. We examine security services to execute applications securely, and propose new performance models considering those services. We design performance models, which describe information retrieval system through N database services, using Petri Net. We compare the performance of two paradigms by assigning numerical values to parameters and measuring the execution time of two paradigms. In this paper, the comparison of two performance models with security services for secure communication shows the results that the execution time of the Remote Procedure Call performance model is sharply increased because of many communications with the high cryptography mechanism between hosts, and that the execution time of the Mobile Agent model is gradually increased because the Mobile Agent paradigm can reduce the quantity of the communications between hosts.

A Study on the actual conditions of the use of them and the moves to strengthen home economics resources for school lifelong education in home economics teachers' view (가정과교사가 인식한 학교 평생교육을 위한 가정과 자원의 활용 실태 및 활성화 방안)

  • Kim, Sung-Hee;Chae, Jung-Hyun
    • Journal of Korean Home Economics Education Association
    • /
    • v.18 no.4 s.42
    • /
    • pp.127-141
    • /
    • 2006
  • The purpose of this study was to investigate the actual conditions of the use of them and the moves to strengthen home economics resources for school lifelong education for parents and local residents. This study conducted a systematic random sampling. Questionnaires were distributed to home economics teachers from 285 middle schools, 123 high schools, and 130 of them were sampled as the subjects of this study. The results of this study were as follows. First, home economics teachers were active participating school lifelong educational program. But according to the result of research on the actual condition, the proportion of taking part in it was low. More than half of home economics teachers who took part in program's lecturer were in charge of computer courses. So they didn't show their ability as expert. Also they were in charge of several works than roll of lecturers. It was mentioned too great a burden. There is little in-service training for meeting specialization for school lifelong education. They wanted to take part of lecturers of program and preferred hours of being over class. More than half of them had intended to obtain a lifelong educator's license. The part of elective courses for obtaining a lifelong educator's license is similar to home economics educational contents. So, they have an advantage of obtaining it. Second, one-fifth of school that gave school life education carried out program of related home economics. Mostly they had mothers of students-oriented programs on artistic and leisure. But this is that home economics teachers mentioned less important teaching at society in the future. They importantly mentioned program on children's education in now and the future. Parents of students and local residents also extremely wanted it. For differentiated school life education, quality of programs is important greatly. Third, the actual condition of practical room relating home economics is only practice to cook mostly. So they are reluctant to be open it because of being responsible for the results from using there. It is necessary to ameliorate there's facilities and to increase there's area. Fourth, home economics teachers want to improve their specialization through in-service training, to develop and diffuse programs of superior quality, and to get extra pay for overtime from the government.

  • PDF

The Regional Classification of Tidal Regime using Characteristics of Astronomical Tides, Overtides and Compound Tides in the Han River Estuary, Gyeonggi Bay (천문조, 배조 및 복합조 특성을 이용한 경기만 한강하구 구역별 조석체계 분류)

  • Yoon, Byung Il;Woo, Seung-Buhm;Kim, Jong Wook;Song, Jin Il
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.27 no.3
    • /
    • pp.149-158
    • /
    • 2015
  • In this study, we investigate tidal wave propagation characteristics, and classify regional tidal regime using tidal form number considered distribution of astronomical tide, overtides, and compound tides in the Han River Estuary, Gyeonggi Bay. The characteristics of the tidal wave propagation in main channels show dominance of major tidal constituents (e.g., $M_2$, $S_2$, $N_2$, $K_1$ and $O_1$) contributing to the astronomical tide however, distinct increasing of shallow water (e.g., $M_4$) and long period (e.g., $MS_f$) components toward up-estuary. Using the characteristics of tidal form number to astronomical tide, overtides, and compound tides, the regional tidal regime could be assorted into three regions. Firstly, a dominance area of astronomical tide was presented from open sea to a front of Incheon Harbor (Yeomha channel) and to north entrance of Seokmo channel. The area between south and north entrance of Yeomha channel and Ganghaw north channel classified into zone of showing strong shallow water components. It could be separated into upper estuary, upstream the Singok underwater dam, showed dominance of shallow overtides (e.g., $M_4$ and $MS_4$) water and long-term compound tides (e.g., $MS_f$) larger magnitude than astronomical tide. The shallow water components was earlier generated in lower part (south entrance) of Yeomha channel have strong bottom by effect of shallower and narrower compared with Seokmo channel. Tidal asymmetries of upper estuary cause by a development of overtides and compound tides are mainly controlled by influence of man-made structure.

Ore Mineralization of The Copper-bearing Hanae Hydrothermal Vein Deposit (하내 함 동 열수 맥상광상의 광화작용)

  • Choi, Sang-Hoon;Lee, Sunjin;Jun, Youngshik
    • Economic and Environmental Geology
    • /
    • v.50 no.6
    • /
    • pp.435-443
    • /
    • 2017
  • The Hanae deposit is located within the Cretaceous Gyeongsang Basin. The Cu-bearing hydrothermal quartz vein formed by narrow open-space filling along fracture in the sedimentary rocks as Jindong Formation. The Hanae Cu-bearing hydrothermal deposit shows a paragenetic sequence of pyrrhotite-pyrite $\rightarrow$ pyrite-chalcopyrite-sphalerite(${\pm}$Bi-bearing tellurides) $\rightarrow$ Ag-bearing telluride mineralization $\rightarrow$ secondary mineralization. Fluid inclusion data indicate that the Hanae Cu-bearing hydrothermal mineralization occurred from dominantly aqueous fluids at temperatures of $400^{\circ}C-200^{\circ}C$. Equilibrium thermodynamic interpretation of the mineral paragenesis and assemblages combined with fluid inclusion data indicate that early main Cu-bearing ore mineralization in the vein starts at about $350^{\circ}C$ which corresponds to sulfur fugacity from about $10^{-9.2}$ to $10^{-8.7}bar$ with oxygen fugacity of about $10^{-32.1}$ to $10^{-29.8}bar$. Late main Cu-bearing ore mineralization in the vein occurs at about $250^{\circ}C$ which corresponds to sulfur fugacity from about $10^{-13.5}$ to $10^{-11.7}bar$ with oxygen fugacity of about $10^{-38.4}$ to $10^{-35.2}bar$. The late Ag-bearing telluride mineralization in the Hanae hydrothermal system occurs at about $200^{\circ}C$ which corresponds to minium Tellirium fugacity value of about $10^{-18}bar$ with sulfur fugacity of about $10^{-14.0}$ to $10^{-10.9}bar$.