• Title/Summary/Keyword: 중국유(中國柚)

Search Result 236, Processing Time 0.03 seconds

Comparison on Antioxidant Activity of Ethanolic Extracts of Chinese Matrimony Vine (Lycium chinensis M.) (구기자 유전자원의 에탄올 추출물의 항산화활성 비교)

  • An, Tae-Hwan;Lee, Suk-Young;Cho, Jin-Woong
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.57 no.1
    • /
    • pp.22-28
    • /
    • 2012
  • This experiment was conducted to find out high antioxidant activity varieties of chinese matrimony from the 131 accessions which conserved at Cheongyang Gugija Experiment Station. The status of the 131 accessions were composed 21 of local varieties, 20 of introduced species and 90 of improved races. The anti-oxidant activity using DPPH and $IC_{50}$, 45 accessions out of 90 showed high activity in free radical scavenging ability as less than $200{\mu}g/m{\ell}$ in improved races, while nine and six accessions from the introduced species and local varieties, respectively. At the stem part, the highest three anti-oxidant varieties among 131 accessions are "C0148-94", "D0148-72" and "Cheongdae", while China collection 1 in leaf part. Since "Cheongdae" is the progeny from the "Cheongyang Jaerae 5" and "Myungan" and those two varieties, "C0148-94" and "D0148-72" are from the Myungan and Cheongdae, high anti-oxidant activity can be inherited in Chinese matrimony vine.

Compilation of Books on Military Arts and Science and Ideology of Military Science in the early Joseon Dynasty (조선(朝鮮) 초기(初期)의 병서(兵書) 편찬(編纂)과 병학(兵學) 사상(思想))

  • Yun, Muhak
    • (The)Study of the Eastern Classic
    • /
    • no.49
    • /
    • pp.325-355
    • /
    • 2012
  • This research aims to generalize the thoughts of military science of the intellectuals through the books on military arts and science, which were published in the early Joseon Dynasty. In the early Joseon dynasty, it was in a position to establish the foundation in the new monarch internally, and, at the same time, to overcome foreign powers on both northern and southern borders externally. Thus, the books on military arts and science should have to be published under a premise of such situations. Accordingly, the books on military arts and science of those days took account of political stability having reflected the activities not only as the founder of Joseon but also as the military officer in the late Goryeo along with the books' own purpose to found military arts and sciences. The books on military arts and science that published in the early Joseon Dynasty were written mostly based on Chinese military books and its annotations, except some descriptions of the history of war. However, the intellectuals at that time endeavored to redefine military arts and science from the perspective of Confucianism having evaluated Chinese military science books that were biased to boost Machiavellian tactics. As a result of this, the geographical distinctions between China and Korea were the start of an argument for the military arts and science. There were also disputes over the relationships between the military science and the Yin-Yang School, and between the military science and Confucian school. Organizing our country's own history of war for the first time in the early Joseon Dynasty is worth for putting a high evaluation. However, it cannot help but to point out the limits of the books that there are noticeable descriptions about the factors related to toadyism, and that there are no descriptions about the wars against Japanese raiders. The books on military arts and science in the early Joseon Dynasty put emphasis on the commander's leadership that should be good at both literary and martial arts, as well as the harmony in military-to-military relations. After all, the intellectuals in the early Joseon Dynasty had linked the military arts and science to the sages of Confucian school under a premise that scholarship is to be used in combination with martial arts. And, as the nexus between the two, they noted the items of virtue, such as humaneness and righteousness (仁義); ritual and music (禮樂); loyalty and filial piety (忠孝); three fundamental principles (三綱); five moral disciplines (五倫). It can be said that this point is the typical features of the military arts and science in the early Joseon Dynasty, which cannot be found in Chinese military classics.

Transition of Rice Culture Practices during Chosun Dynasty through Old References V. Cultivation and Cropping Patterns (주요 고농서를 통한 조선시대의 도작기술 전개 과정 연구 V. 재배양식)

  • Lee, Sung-Kyum;Guh, Ja-Ok;Lee, Eun-Woong;Lee, Hong-Suk
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.37 no.1
    • /
    • pp.104-115
    • /
    • 1992
  • The rice culture techniques included 'Jodosukyungbeob'(旱稻水耕法 : culture techniques of early-ripening paddy rice), 'Mandosukyungbeob' (晩稻水耕法) : culture techniques of late-Ripening paddy rice 'Handobeob'(旱稻<山稻>法 : culture techniques of upland rice), 'Myojongbeob'(苗種法 : culture techniques of paddy rice by transplanting), 'Kunangbeob'(乾秧法 : culture techniques of rice by transplanting which rears seeding in dry paddy) and 'Sudogunpanongbeob'(水稻乾播農法 : culture techniques of paddy rice seeding in dry field). Especially, 'Kunangbeob' and 'Sudogunpanongbeob' were originally developed in Korea as seen in 1600s(Kyoungje : 經濟) and early 1800s (Yoji : 要旨). In 'Jodosukyungbeob' it took 9 days for seed dipping, water-sprouting and prevent damage by birds, each for 3 days in China, but in Korea seed dipping in water took 3 days and the rest of the procedures were flexibly established. In matured soils, practices were fall plowing right after harvest, recognition of effective tillering and additional fertilization use of human manure, and stimulation of sprouting by lime application. The unique culture techniques adequate for Korean situations were practiced, which included weed control after draining accurately for 3 to 4 times, draining at mid season for improving wind and drought tolerance, rice harvesting at appropriate time for preventing grain shattering, and seeding in rows. 'Mandosukyungbeob' was improved techniques contrast to those of China, and the major contents were selection of proper varieties, good stand establishment by seeding high rates, induction of vigorous tillers, and adoption of 'Jokjongbeob'(足種法 : seeding method by foot). Also, one of the most prominent rice cultures by our ancestors was 'Kunpanongbeob' that was systemized form habitual practice of Pyongan Province. The unique technique actualized was 'Hando [旱稻(山稻)]' culture technique which was the combinations of 'Jokjongbeob', root stimulation method, and disaster-tolerant mixture cropping with adoptation of variety theory, although it was originated from China. The transplanting techniques has come before 'Jikseol'($\ulcorner$直說$\lrcorner$) and its merits were sufficiently realized. However, this method was basically prohibited from the early Chosun dynasty because extremely bad harvest was expected under drought conditions and insufficient conditions of water storage. But, it was permitted in the areas that contained water all the times and in case of large-scale farming especially. Most of rice culture was transplanted in the end of the Chosun dynasty because transplanting was continuously spreaded in the three southern provinces of Korea. Under these circumstances, transplanting technique was improved from the early to the end of the Chosun dynasty by weed control, fertilizing, water management, and quadratic transplanting. Based on these techniques, agricultural productivity was improved 5 times by that time. 'Kunpanongbeob' was created and developed properly for Korean conditions that is dry in early season and flooding in late season. This was successively developed and established into transplanting technique of nursery seedling.

  • PDF

Severe Outbreak of Rice Stripe Virus and Its Occurring Factors (벼줄무늬잎마름바이러스의 대 발생과 발생 요인)

  • Kim, Jeong-Soo;Lee, Gwan-Seok;Kim, Chang-Seok;Choi, Hong-Soo;Lee, Soo-Heon;Kim, Mi-Kyeong;Kwag, Hae-Ryun;Nam, Mun;Kim, Jeong-Sun;Noh, Tae-Hwan;Kang, Mi-Hyung;Cho, Jeom-Deog;Kim, Jin-Young;Kang, Hyo-Jung;Han, Jong-Woo;Kim, Byung-Ryun;Jeong, Sung-Soo;Kim, Ju-Hee;Kuo, Sug-Ju;Lee, Jung-Hwan;Kim, Tae-Sung
    • The Korean Journal of Pesticide Science
    • /
    • v.15 no.4
    • /
    • pp.545-572
    • /
    • 2011
  • The genetic diagnosis methods by RT-PCR and Virion capture (VC)/RT-PCR against Rice stripe virus (RSV) were developed. Three diagnosis methods of seedling test, ELISA and RT-PCR were compared in virus detection sensitivity (VDS) for RSV. The VDS of ELISA for RSV viruliferous small brown plant hopper (SBPH) was higher with 40.5% than that of seedling test. The VDS of RT-PCR was higher with 21% than that of ELISA. The VDS of ELISA and VC/RT-PCR was same with 9.2% in average on the SBPH collected from fields at the areas of Gimpo, Pyungtaeg and Sihueng, Gyeonggi province in 2009. The specific primers of RSV for SBPH and rice plant were developed for the diagnosis by Real time PCR. The RQ value of Real time PCR for the viruliferous and non viruliferous SBPH was 1 for 50 heads of non viruliferous SBPH, 96.5 for 50 heads of viruliferous SBPH, 23.1 for 10 heads of viruliferous SBPH + 40 heads of non viruliferous SBPH, and 75.6 for 30 heads of viruliferous SBPH + 20 heads of non viruliferous SBPH. The RQ value was increased positively by the ratio of viruliferous SBPH. Full sequences of 4 genomes of RSV RNA1, RNA2, RNA3 and RNA4 were analysed for the 13 RSV isolates from rice plants collected from different areas. Genetic relationships among the RSV isolates of Korea, Japan and China were classified as China + Korea, and China + Korea + Japan by phylogenetic analysis for RSV RNA1 and RNA2. In case of RNA3 involved in pathogenicity, genetic relationship of RSV among the three countries was grouped into 3 as China, China + Korea, and Korea + Japan. According to the genetic relationships in RSV RNA4, RSV isolates were grouped into 4 as China, Korea, China + Korea + Japan, and Korea + Japan. Viruliferous insect rate (VIR) of RSV in average increased in each year from 2008 to 2010, and the rates were 4.3%, 6.1%, and 7.2%, respectively, at the 28 major rice production areas in 7 provinces including Gyeonggido. The highest VIR in each year was 11.3% of Gyeonggido in 2008, 20.1% of Jellanamdo in 2009 and 14.2% of Chungcheongbukdo in 2010. The highest VIR depending upon the investigated areas was 22.1% at Buan of Jellabukdo in 2008, 36% at Wando and Jindo of Jellanamdo in 2009, and 30.0% at Boeun of Chungcheongbukdo in 2010. Average population density (APD) of overwintered SBPH was 13.1 heads in 2008, 13.9 heads in 2009 and 5.6 heads in 2010. The highest APD was 39.1 and 60.4 heads at Buan of Jellabukdo in 2008 and 2009, respectively, and 14.0 heads at Pyungtaeg of Gyeonggido. The acreage of RSV occurred fields was 869 ha in the western and southern parts, mainly at Jindo and Wando areas, of Jellanamdo in 2008. In 2009, RSV occurred in the acreage of 21,541 ha covered whole country, especially, partial and whole plant death were occurred with infection rate of 55.2% at 3,025 plots in 53 Li, 39 Eup/Myun, 19 Si/Gun of Gyeonggido, Incheonsi, Chungcheongnamdo, Jeollabukdo and Jeollanamdo. Seasonal development of overwintered SBPH was investigated at Buan, Jeollabukdo, and Jindo, Jeollanamdo for 3 years from 2008. Most SBPH developed to the 3rd and 4th instar on the periods of May 20 to June 10, and they developed to the adult stage for the 1st generation on Mid and Late June. In 2009, all SBPH trapped by sky net trap were adult on May 31 to June 1 at Mid-western aeas of Taean, Seosan and Buan, and South-western areas of Sinan and Jindo. The population density of adult SBPH was 963 heads at Taean, 919 at Seocheon and 819 at Sinan area. The origin of these higher population of adult SBPH were verified from the population of non-overwintered SBPH but immigrant SBPH. From Mid May to Mid June in 2010, adult SBPH could not be counted as immigrant insects by sky net trap. The variation of RSV VIR was high with 2.1% to 9.5% for immigrant adult SBPH trapped by sky net trap at Hongsung of Chungcheongbukdo, Buan of Jeollabukdo and so forth in 2009. The highest VIR for the immigrant adult SBPH was 9.5% at Boryung of Chungcheongnamdo, followed by 7.9% at Hongsung of Chungcheongnamdo, 6.5% at Younggwang of Jeollanamdo, and 6.4% at Taean of Cheongcheongnamdo. The infection rate of RSV on rice plants induced by the immigrant adult SBPH cultivated near sky net trap after about 10 days from immigration on June 12 in 2009 was 84.6% at Taean, 65.4% at Buan and 92.9% at Jindo, and 81% in average through genetic diagnosis of RT-PCR. Barley known as a overwintering host plant of RSV had very low infection rate of 0.2% from 530 specimens collected at 10 areas covering whole country including Pyungtaeg of Gyeonggido. Twenty nine plant species were newly recorded as natural hosts of RSV. In winter annual plant species, 11 plants including Vulpia myuros showed RSV infection rate of 24.9%. The plant species in summer annual ecotype were 13 including Digitaria ciliaris with 44.9%, Echinochloa crusgalli var. echinata with 95.2% and Setaria faberi with 65.5% in infection rate of RSV. Five perennial plants including Miscanths sacchariflorus with infection rate of 33.3% were recorded as hosts of RSV. Rice cultivars, 8 susceptible cultivars including Donggin1 and 17 resistant ones including Samgwang, were screened in field conditions at 3 different areas of Buan, Iksan and Ginje in 2009. All the susceptible cultivars were showed typical symptom of mosaic and wilt. In 17 genetic resistant cultivar, 12 cultivars were susceptible, however, 5 cultivars were field-resistant plus genetic resistant to RSV as non symptom expression. When RSV was artificially inoculated at seedling stage to 4 cultivars known as genetic resistant and 3 cultivars known as genetic susceptible, the symptom expression in resistant cultivars was lower as 19.3% in average than that of 53.3% in susceptible ones. In comparison of symptom expression rate and viral infection rate using resistant Nampyung and susceptible Heugnam cultivars by artificial inoculation of RSV at seedling stage, the symptom expression of Heugnam was higher as 28% than 12% of Nampyung. However, virion infection of resistant Nampyung cultivar was higher as 12% reversely than 85% of susceptible Heugnam. Yield loss of rice was investigated by the artificial inoculation of RSV at the seedling stage of resistant cultivars of Nampyung and Onnuri, and susceptible cultivars of Donggin1 and Ungwang for 3 years from 2008. The average yield per plant was 7.8 g, 8.5 g and 13.8 g on rice plants inoculated at seedling stage, tillering stage and maximum tillering stage, respectively. The yield loss rate was increased by earlier infection of RSV with 51% at seedling stage, 46% at tillering stage and 13% at maximum tillering stage. In resistant rice cultivars, there was no statistically significant relation between infection time and yield loss. In natural fields on susceptible rice cultivar of Ungwang at Taean and Jindo areas in 2009, the yield loss rate was increased with same tendency to the infection hill rate having the corelation coefficient of 0.94 when the viral infection was over 23.4%.

Changes in Contents of Chlorophyll and Free Proline as Affected by NaCl in Rice Seedling (NaCl처리에 따른 벼 유묘기의 엽록소 및 유리 Proline의 함량 변화)

  • 이강수;이종신;최선영
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.37 no.2
    • /
    • pp.178-184
    • /
    • 1992
  • The changes in contents of chlorophyll and free proline in the seedling leaves of ten rice cultivars as affected by salt stress were checked in order to obtain the basic information on the judgement of the degrees of salt injury. The difference in salt injury among the cultivars was clearly observed about 25 days after 6% salt treatment. Chlorophyll content was decreased in both Gayabyeo and Taebaegbyeo for 14 days after different salt treatment as salt concentration was increased and the decreased tendency was much higher in Taebaegbyeo than in Gayabyeo over 0.4% salt concentration. Chlorophyll content in Gayabyeo after 0.6% salt treatment was decreased slowly, while in Taebaegbyeo, deminished very rapidly as time progressed, therefore it decreased by about 16% in Gayabyeo and 67% in Taebaebyeo compared to the control at 20 days, respectively. The relationship between chlorophyll content and the degrees of salt injury in ten rice cultivars showed significant negative correlation at 10 day after 0.6% salt treatment. Free proline content in Gayabyeo was increased gradually for 14 days after different salt treatment as salt became higher, while in Taebaebyeo, it was increased rapidly under 0.6% but rather decreased under 0.8% salt concentration. Particularly, it was much higher Taebaegbyeo than in Gayabyeo under salt concentration from 0.4 to 0.6%. Free proline content in Gayabyeo after 0.6% salt treatment was increased from 15 days, on the other hand in Taebaegbyeo, it was increased from 5 days, but rather decreased from 20 days, and it was 6 times higher in Taebaegbyeo than in Gayabyeo at 10 days. There was significant positive correlation between free proline content and the degrees of salt injury in ten rice cultivars at 10 days after 0.6% salt treatment. From the above results, chlorophyll and free proline content may be used as an indicative character of intensity of salt stress as well as varietal difference in resistance to salt stress in the seedling stage.

  • PDF

Performance Evaluation of Monitoring System for Sargassum horneri Using GOCI-II: Focusing on the Results of Removing False Detection in the Yellow Sea and East China Sea (GOCI-II 기반 괭생이모자반 모니터링 시스템 성능 평가: 황해 및 동중국해 해역 오탐지 제거 결과를 중심으로)

  • Han-bit Lee;Ju-Eun Kim;Moon-Seon Kim;Dong-Su Kim;Seung-Hwan Min;Tae-Ho Kim
    • Korean Journal of Remote Sensing
    • /
    • v.39 no.6_2
    • /
    • pp.1615-1633
    • /
    • 2023
  • Sargassum horneri is one of the floating algae in the sea, which breeds in large quantities in the Yellow Sea and East China Sea and then flows into the coast of Republic of Korea, causing various problems such as destroying the environment and damaging fish farms. In order to effectively prevent damage and preserve the coastal environment, the development of Sargassum horneri detection algorithms using satellite-based remote sensing technology has been actively developed. However, incorrect detection information causes an increase in the moving distance of ships collecting Sargassum horneri and confusion in the response of related local governments or institutions,so it is very important to minimize false detections when producing Sargassum horneri spatial information. This study applied technology to automatically remove false detection results using the GOCI-II-based Sargassum horneri detection algorithm of the National Ocean Satellite Center (NOSC) of the Korea Hydrographic and Oceanography Agency (KHOA). Based on the results of analyzing the causes of major false detection results, it includes a process of removing linear and sporadic false detections and green algae that occurs in large quantities along the coast of China in spring and summer by considering them as false detections. The technology to automatically remove false detection was applied to the dates when Sargassum horneri occurred from February 24 to June 25, 2022. Visual assessment results were generated using mid-resolution satellite images, qualitative and quantitative evaluations were performed. Linear false detection results were completely removed, and most of the sporadic and green algae false detection results that affected the distribution were removed. Even after the automatic false detection removal process, it was possible to confirm the distribution area of Sargassum horneri compared to the visual assessment results, and the accuracy and precision calculated using the binary classification model averaged 97.73% and 95.4%, respectively. Recall value was very low at 29.03%, which is presumed to be due to the effect of Sargassum horneri movement due to the observation time discrepancy between GOCI-II and mid-resolution satellite images, differences in spatial resolution, location deviation by orthocorrection, and cloud masking. The results of this study's removal of false detections of Sargassum horneri can determine the spatial distribution status in near real-time, but there are limitations in accurately estimating biomass. Therefore, continuous research on upgrading the Sargassum horneri monitoring system must be conducted to use it as data for establishing future Sargassum horneri response plans.

A Study on the Distribution, Contents and Types of Stone Inscription of Wuyi-Gugok in China (중국 무이구곡 바위글씨(石刻)의 분포와 내용 및 유형에 관한 연구)

  • Rho, Jae-Hyun;Cheng, Zhao-Xia;Kim, Hong-Gyun
    • Journal of the Korean Institute of Traditional Landscape Architecture
    • /
    • v.38 no.1
    • /
    • pp.115-131
    • /
    • 2020
  • Through literature research and field investigation, this paper attempts to study the distribution, morphology and the typification of the visual and perceptual stone inscription in Wuyi-Gugok of China. The results are as follows: First, there are 350 stone inscriptions in total from the 1st Gok to 9th Gok in Wuyi-Gugok. Second, according to the analysis of the stone inscription distribution, 74(21.2%) stone inscriptions in the 5th Gok, 67(19.2%) in the 6th Gok, 65(18.6%) in the 1st Gok, 60(17.2%) in the 2nd Gok and 53(15.2%) in the 4th Gok are confirmed. The above five Goks contain 319(91.1%) stone inscriptions, so they have rich cultural landscape. Third, according to the survey, the number of the stone inscriptions existed in the Sugwangseok of the 1st Gok are 41(22.6%), in the Homagan of Cheonyubong of the 6th Gok are 29(8.3%), in the Jesiam of the 4th Gok are 23(6.6%), in the Nyeongam of the 2nd Gok are 22(6.3%), in the Hyangseongam of the 6th Gok are 21(6%), in the Unwa of the 5th Gok are 19(5.4%), in the Bokhoam of the 5th Gok are 18(5.1%), in the Eunbyeongbong of the 5th Gok are 17(4.9%), in the Daejangbong of the 4th Gok are 14(4%), in the Daewangbong of the 1st Gok and the Geumgokam of the 4th Gok are 12(3.4%). Thus, a total of 228 (65.1%) stone inscriptions are concentrated in these 11 sites, which represent the popularity and cultural value of these rocks. Fourth, the stone inscription of Wuyi-Gugok, praising the landform and topographical geological landscape of Mount Wuyi, mainly describe the scenic name of each Gok related to Zhu Xi's Gugok culture, appreciate Zhu Xi's tracks and the stone inscription in the sacred land of Neo-Confucianism culture, and also record the Confucian edification of mencius thoughts, Muigun(武夷君) and the myths and legends related to the site names of Wuyi mountain, which can remind people of the worldview of the celestial paradise where the gods live and the fairyland of the land of peach blossoms. In addition, it indicates that the historical and cultural landscape, which is full of colorful history and myths and legends, including allusions related to Confucian, buddhist and Taoist celebrities and the ancestor ancient things related to traditional culture of China is very diverse. Fifth, the results of the classification, based on the content of the stone inscription in Wuyi-Gugok, are classified as the scenery name inscription, the praise scene inscription, the recording travel inscription, the recording event inscription, the philosophy inscription, the expressing emotion inscription, the religion inscription, the inscription for auspiciousness, the slogan and expressing ambition inscription and the official document notice inscription, among which there are 102(29.1%) praise scene inscriptions, 93(26.6%) scenery name inscriptions and 61(17.4%) recording travel inscriptions. The stone inscriptions of Wuyi-Gugok have the characteristics of the special emphasis on scenery names, landscape praise and commemorative tours. Sixth, the analysis of the intertext between the 「Figure of Wuyi-Gugok」 and Wuyi-Gugok rock letters, in the study found that the method of propagation between media was mostly the method of propagation of quotations and maintained intermedia through extension, repetition, extension, and compression.

Analysis of Overseas LNG Bunkering Business Model (해외 LNG벙커링 비즈니스 모델 분석)

  • Kim, Ki-Dong;Park, So-Jin;Choi, Kyoung-Sik;Cho, Byung-Hak;Oh, Yong-Sam;Cho, Sang-Hoon;Cha, Keunng-Jong;Cho, Won-Jun;Seong, Hong-Gun
    • Journal of the Korean Institute of Gas
    • /
    • v.22 no.1
    • /
    • pp.37-44
    • /
    • 2018
  • As the international Maritime Organization is tightening up the emission regulation vessel, many countries and companies are pushing ahead the LNG fuel as one of long term solution for emission problems of ship. as a study on the way to conduct business for LNG bunkering around the world, this study was analyzed in view-point of business models focused on major countries such as Japan, China, Singapore, Europe and United States. The results of this study are as follows. China first established a nation-centered LNG bunkering policy. And then, the state and the energy company have been cooperating and carrying on LNG bunkering business for LNG fueled ships. Some countries in Europe and United States are in the process of LNG bunkering business mainly with private company. To obtain cheaper LNG fuel than bunker-C, the private company has a business model of LNG bunkering on their own LNG fueled ships, while securing LNG with high price competitiveness through partnership with middle class operators such us LNG terminal and natural gas liquefaction plant. Also, the LNG bunkering business around the world is focused on private companies rather than public corporations, but it was going to be focused on large energy companies because the initial cost required to build LNG bunkering infrastructure. Three models (TOTE model, Shell model, ENGIE model) of LNG bun kering business are currently being developed. It has been found that the way in which LNG bunkering business is implemented by different countries is applied differently according to the enterprise and national policy.

A systematic study of the Polygonum amphibium L. complex (Polygonaceae) based on chloroplast DNA sequences (엽록체 DNA 염기서열에 근거한 물여뀌 종집단(마디풀과)의 분류학적 연구)

  • Yaqian, Gao;Bhandari, Gauri Shankar;Park, Jin Hee;Park, Chong-Wook
    • Korean Journal of Plant Taxonomy
    • /
    • v.43 no.1
    • /
    • pp.34-45
    • /
    • 2013
  • The Polygonum amphibium complex (Poygonaceae) is a highly polymorphic taxon that can grow in aquatic environments as well as in moist terrestrial habitats. Aquatic and terrestrial plants of the P. amphibium complex vary significantly in morphology and exhibit very complicated patterns of morphological variation, resulting in the description of numerous infra-specific taxa. Principal components analysis of 107 individuals of the P. amphibium complex from Asia and North America using 11 morphological characters showed that the aquatic plants can be discerned from the terrestrial plants by leaf size, shape, and petiole length. In contrast, both aquatic and terrestrial plants collected from the same population or locality shared identical sequences in the matK, psbA-trnH IGS, rbcL-accD IGS and trnL-trnF regions of the chloroplast DNA (cpDNA), suggesting that aquatic and terrestrial forms of the P. amphibium complex are not genetically diverged; morphological differences between the two forms are probably due to the differences in environmental conditions of the habitats. In addition, results from the morphological analysis and the maximum parsimony analysis of the cpDNA data set revealed that the plants from Asia including Korea, Japan, China, Mongolia and Russia Far East are diverged from those in North America and Europe, suggesting that the Asian populations should be recognized as a distinct variety, P. amphibium var. amurense Korsh.

A Study on the Strategies for Incheon International Airport to be a Successful Hub Airport in Northeast Asia (인천국제공항의 동북아 허브화 성공을 위한 전략 -한·일 항공시장 분석을 중심으로-)

  • Yoo, Kwang Eui
    • Journal of Advanced Navigation Technology
    • /
    • v.1 no.1
    • /
    • pp.81-94
    • /
    • 1997
  • The construction of Incheon International Airport(IIA) was planned in order to meet the national air transport demand which has been rapidly increased, and to be a major hub airport in Northeast Asia. However, it is inevitable to compete with Japanese airports because Japanese government also planned to expand greatly the airport capacity in Tokyo area and Kansai Airport in Osaka area. Since a hub airport should have convenient connecting flights to spoke cities, it is required for IIA to have plenty of short-haul flights to the cities around Seoul, for example, to the cities in East China, Japan and other East Asian countries. IIA authority and Korean national air carriers should coordinate to develop air transport demand for short-haul international route and establish efficient hub-spoke flight schedules. This would be a essential precondition to function as a hinterland hub in Northeast Asia. Reflecting the geographical position, the function as a hourglass hub could be possible, if IIA is utilised by major airlines as a bridge to connect passengers between cities in Southeast Asia and 'cities in North America. To be a successful hourglass hub, the Korean national carriers must try to engage in the joint operations or the alliances with the major airlines of Southeastern countries or North American countries. All of these could be accomplished through the cooperation among government, airport and national air carriers.

  • PDF