• Title/Summary/Keyword: local region

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Recent Research for the Seismic Activities and Crustal Velocity Structure (국내 지진활동 및 지각구조 연구동향)

  • Kim, Sung-Kyun;Jun, Myung-Soon;Jeon, Jeong-Soo
    • Economic and Environmental Geology
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    • v.39 no.4 s.179
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    • pp.369-384
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    • 2006
  • Korean Peninsula, located on the southeastern part of Eurasian plate, belongs to the intraplate region. The characteristics of intraplate earthquake show the low and rare seismicity and the sparse and irregular distribution of epicenters comparing to interplate earthquake. To evaluate the exact seismic activity in intraplate region, long-term seismic data including historical earthquake data should be archived. Fortunately the long-term historical earthquake records about 2,000 years are available in Korea Peninsula. By the analysis of this historical and instrumental earthquake data, seismic activity was very high in 16-18 centuries and is more active at the Yellow sea area than East sea area. Comparing to the high seismic activity of the north-eastern China in 16-18 centuries, it is inferred that seismic activity in two regions shows close relationship. Also general trend of epicenter distribution shows the SE-NW direction. In Korea Peninsula, the first seismic station was installed at Incheon in 1905 and 5 additional seismic stations were installed till 1943. There was no seismic station from 1945 to 1962, but a World Wide Standardized Seismograph was installed at Seoul in 1963. In 1990, Korean Meteorological Adminstration(KMA) had established centralized modem seismic network in real-time, consisted of 12 stations. After that time, many institutes tried to expand their own seismic networks in Korea Peninsula. Now KMA operates 35 velocity-type seismic stations and 75 accelerometers and Korea Institute of Geoscience and Mineral Resources operates 32 and 16 stations, respectively. Korea Institute of Nuclear Safety and Korea Electric Power Research Institute operate 4 and 13 stations, consisted of velocity-type and accelerometer. In and around the Korean Peninsula, 27 intraplate earthquake mechanisms since 1936 were analyzed to understand the regional stress orientation and tectonics. These earthquakes are largest ones in this century and may represent the characteristics of earthquake in this region. Focal mechanism of these earthquakes show predominant strike-slip faulting with small amount of thrust components. The average P-axis is almost horizontal ENE-WSW. In north-eastern China, strike-slip faulting is dominant and nearly horizontal average P-axis in ENE-WSW is very similar with the Korean Peninsula. On the other hand, in the eastern part of East Sea, thrust faulting is dominant and average P-axis is horizontal with ESE-WNW. This indicate that not only the subducting Pacific Plate in east but also the indenting Indian Plate controls earthquake mechanism in the far east of the Eurasian Plate. Crustal velocity model is very important to determine the hypocenters of the local earthquakes. But the crust model in and around Korean Peninsula is not clear till now, because the sufficient seismic data could not accumulated. To solve this problem, reflection and refraction seismic survey and seismic wave analysis method were simultaneously applied to two long cross-section traversing the southern Korean Peninsula since 2002. This survey should be continuously conducted.

Introduction of region-based site functions into the traditional market environmental support funding policy development (재래시장 환경개선 지원정책 개발에서의 지역 장소적 기능 도입)

  • Jeong, Dae-Yong;Lee, Se-Ho
    • Proceedings of the Korean DIstribution Association Conference
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    • 2005.05a
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    • pp.383-405
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    • 2005
  • The traditional market is foremost a regionally positioned place, wherein the market directly represents regional and cultural centered traits while it plays an important role in the circulation of facilities through reciprocal, informative and cultural exchanges while sewing to form local communities. The traditional market in Korea is one of representative retail businesses and premodern marketing techniques by family owned business of less than five members such as product management, purchase method, and marketing patterns etc. Since the 1990s, the appearance of new circulation-type businesses and large discount convenience stores escalated the loss of traditional competitiveness, increased the living standard of customers, changed purchasing patterns, and expanded the ubiquity of the Internet. All of these changes in external circulation circumstances have led the traditional markets to lose their place in the economy. The traditional market should revive on a regional site basis through the formation of a community of regional neighbors and through knowledge-sharing that leads to the creation of wealth. For the purpose of creating a wealth in a place, the following components are necessary: 1) a facility suitable for the spatial place of the present, 2)trust built through exchanges within the changing market environment, which would simultaneously satisfy customer's desires, 3) international bench marking on cases such as regionally centered TCM (England), BID (USA), and TMO (Japan) so that the market unit of store placement transfers from a spot policy to a line policy, 4)conversion of communicative conception through a surface policy approach centered around a macro-region perspective. The budget of the traditional market funding policy was operational between 2001 and 2004, serving as a counter move to solve the problem of the old traditional market through government intervention in regional economies to promote national economic strength. This national treasury funding project was centered on environmental improvement, research corps, and business modernization through the expenditure of 3,853 hundred million won (Korean currency). However, the effectiveness of this project has yet to be to proven through investigation. Furthermore, in promoting this funding support project, a lack of professionalism among merchants in the market led to constant limitations in comprehensive striving strategies, reduced capabilities in middle-and long-term plan setup, and created reductions in voluntary merchant agreement solutions. The traditional market should go beyond mere physical place and ordinary products creative site strategies employing the communicative approach must accompany these strategies to make the market a new regional and spatial living place. Thus, regarding recent paradigm changes and the introduction of region-based site functions into the traditional market, acquiring a conversion of direction into the newly developed project is essential to reinvestigate the traditional market composed of cultural and economic meanings, for the purpose of the research. Excavating social policy demands through the comparative analysis of domestic and international cases as well as innovative and expert management leadership development for NPO or NGO civil entrepreneurs through advanced case research on present promotion methods is extremely important. Discovering the seeds of the cultural contents industry cored around regional resource usages, commercializing regionally reknowned products, and constructing complex cultural living places for regional networks are especially important. In order to accelerate these solutions, a comprehensive and systemized approach research operated within a mentor academy system is required, as research will reveal distinctive traits of the traditional market in the aging society.

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Air Cavity Effects on the Absorbed Dose for 4-, 6- and 10-MV X-ray Beams : Larynx Model (4-, 6-, 10-MV X-선원에서 공기동이 흡수선량에 미치는 효과 : 후두모형)

  • Kim Chang-Seon;Yang Dae-Sik;Kim Chul-Yong;Choi Myung-Sun
    • Radiation Oncology Journal
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    • v.15 no.4
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    • pp.393-402
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    • 1997
  • Purpose : When an x-ray beam of small field size is irradiated to target area containing an air cavity, such as larynx, the underdosing effect is observed in the region near the interfaces of air and soft tissue. With a larynx model, air cavity embedded in tissue-equivalent material, this study is intonded for examining Parameters, such as beam quality, field size, and cavity size, to affect the dose distribution near the air cavity. Materials and Methods : Three x-rar beams, 4-, 6- and 10-MV, were employed to Perform a measurement using a 2cm $(width){\times}L$ (length in cm, one side of x-ray field used 2cm (height) air cavity in the simulated larynx. A thin window parallel-plate chamber connected to an electrometer was used for a dosimetry system. A ratio of the dose at various distances from the cavity-tissue interface to the dose at the same points in a homogeneous Phantom (ebservedlexpected ratio, O/E) normalized buildup curves, and ratio of distal surface dose to dose at the maximum buildup depth were examined for various field sizes. Measurement for cavity size effect was performed by varying the height (Z) of the air cavity with the width kept constant for several field sizes. Results : No underdosing effect for 4-MV beam for fields larger than $5cm\times5cm$ was found For both 6- and 10-MV beams, the underdosing portion of the larynx at the distal surface was seen to occur for small fields, $4cm\times4cm\;and\;5cm\times5cm$. The underdosed tissue was increased in its volume with beam energy even for similar surface doses. The relative distal surface dose to maximum dose was changed to 0.99 from 0.95, 0.92, and 0.91 for 4-, 6-, and 10-MV, respectively, with increasing field size, $4cm\times4cm\;to\;8cm\times8cm$, For 6- and 10-MV beams, the dose at the surface of the cavity is measured less than the predicted by about two and three percent. respectively. but decrease was found for 4-MV beam for $5cm\times5cm$ field. For the $4cm\timesL\timesZ$ (height in cm). varying depth from 0.0 to 4.8cm, cavity, O/E> 1.0 was observed regardless of the cavity size for any field larger than about $8cm\times8cm$. Conclusion : The magnitude of underdosing depends on beam energy, field size. and cavity size for the larynx model. Based on the result of the study. caution must be used when a small field of a high quality x-ray beam is irradiated to regions including air cavities. and especially the region where the tumor extends to the surface. Low quality beam. such as. 4-MV x-ray, and larger fields can be used preferably to reduce the risk of underdosing, local failure. In the case of high quality beams such as 6- and 10-MV x-rays, however. an additional boost field is recommended to add for the compensation of the underdosing region when a typically used treatment field. $8cm\times8cm$, is employed.

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A Study on the Characteristics of Stream Flow Path and Water System Distribution in Gugok Garden, Korea (한국 구곡원림(九曲園林)의 하천 유로 및 수계별 분포 특성)

  • Rho, Jae-Hyun;Choi, Young-Hyun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.39 no.4
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    • pp.50-65
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    • 2021
  • In this study, the water flow system by measuring the flow-way type and distance of flow path that composes the Gugok through literature survey, field survey, and map work on Gugok gardens in Korea whose existence has been confirmed, while investigating and analyzing watersheds, river orders, and river grades. It was intended to reveal the watershed distribution and stream morphological characteristics of the Gugok gardens and to use them as basic data for future enjoyment and conservation of the Gugok gardens. The conclusion of the study is as follows. First, Of the 93 Gugok gardens that have been confirmed to exist, it was found that 11 places(11.8%) were found to have a descending(top-down) type of Gugok that develops while descending along a stream. Second, As a result of analysis of the length of the flow path for each valley, Okryudonggugok(玉流洞九曲, Namsan-gugok) in Gimcheon, Gyeongsangbuk-do was found to have the shortest length of 0.44km among the surveyed valleys, while the flow distance of Muheulgugok(武屹九曲) located in Seongju-gun and Gimcheon-si, Gyeongsangbuk-do was 31.1km, showing the longest flowing distance. The average flow path length of the Gugok Garden in Korea was 6.24km, and the standard deviation was 4.63km, indicating that the deviation between the 'curved type'e and the 'valley type' was severe. In addition, 14(15.1%) Gugok gardens were found to be partially submerged due to dam construction. Third, As a result of analyzing the waters area where Gugok garden is located, the number of Nakdong river basins was much higher at 52 sites(55.9%), followed by the Hangang river basin at 27 sites(28.7%), the Geum river basin at 9 sites(9.7%), and the Yeongsan river and Seomjin river basins at 5(5.4%). Fourth, All Gugok gardens located in the Han river region were classified as the Han river system, and the Gugok garden located on the Nakdong river was classified as the main Nakdong river system, except for 7 places including 5 places in the Nakdong Gangnam Sea water system and 2 places in the Nakdong Gangdong sea water system. As a result of synthesizing the river order of the flow path where Gugok garden is located, Gugok, which uses the main stream as the base of Gugok, is 3 places in the Hangang water system, 5 places in the Nakdong river system, 2 places in the Geumgang water system, and 1 place in the Yeongsangam/Seomjin river system. A total of 11 locations(11.5%) were found, including 36 locations(38.2%) in the first branch, 29 locations(31.2%) in the second branch, and 16 locations(17.0%) in the third branch. And Gugok garden, located on the 4th tributary, was found to be Taehwa Five-gok(太華五曲) set in Yonghwacheon Stream in Cheorwon in the Han river system, and Hoenggyegok(橫溪九曲) in Yeongcheon Hoenggye Stream in the Nakdong river system. Fifth, As a result of the river grade analysis of the rivers located in the Gugok garden Forest, the grades of the rivers located in the Gugok garden were 13 national rivers(14.0%), 7 local first-class rivers(7.5%), and 74 local second-class rivers(78.5%) was shown.

Exposure Assessments of Environmental Contaminants in Ansim Briquette Fuel Complex, Daegu(II) - Concentration distribution and exposure characteristics of TSP, PM10, PM2.5, and heavy metals - (대구 안심연료단지 환경오염물질 노출 평가(II) - TSP, PM10, PM2.5 및 중금속 농도분포 및 노출특성 -)

  • Jung, Jong-Hyeon;Phee, Young-Gyu;Lee, Jun-Jung;Oh, In-Bo;Shon, Byung-Hyun;Lee, Hyung-Don;Yoon, Mi-Ra;Kim, Geun-Bae;Yu, Seung-do;Min, Young-Sun;Lee, Kwan;Lim, Hyun-Sul
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.25 no.3
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    • pp.380-391
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    • 2015
  • Objectives: The objective of this study is to assess airborne particulate matter pollution and its effect on health of residents living near Ansim Briquette Fuel Complex and its vicinities. Also, this study measured and analyzed the concentration of TSP, $PM_{10}$, $PM_{2.5}$, and heavy metals which influences on the environmental and respiratory disease in Ansim Briquette Fuel Complex, Daegu, Korea. Methods: In this study, we analyzed various environmental pollutants such as particulate matter and heavy metals from Ansim Briquette Fuel Complex that adversely affected local residents's health. In particular, we verified the concentration distribution and characteristics of exposure for TSP, $PM_{10}$, and $PM_{2.5}$ among particulate matters, and heavy metals(Cd, Cr, Cu, Mn, Ni, Pb, Fe, Zn, and Mg). In that regard, the official test method on air pollution in Korea for analysis of particulate matter and heavy metal in atmosphere were conducted. The large capacity air sampling method by the official test method on air pollution in Korea were applied for sampling of heavy metals in atmosphere. In addition, we evaluated the concentration of seasonal environmental pollutants for each point of residence in Ansim Briquette Fuel Complex and surrounding area. The sampling measured periods for air pollutants were from August 11, 2013 to February 21, 2014. Furthermore, we measured and analyzed the seasonal concentrations(summer, autumn and winter). Results: The average concentration for TSP, $PM_{10}$, and $PM_{2.5}$ by direct influence area at Ansim Briquette Fuel Complex were 1.7, 1.4 and 1.9 times higher than reference region. In analysis results of seasonal concentrations for particulate matter in four direct influence and reference area, concentration levels for winter were generally somewhat higher than concentrations for summer and autumn. The average concentrations for Cd, Cr, Mn, Ni, Pb, Fe, and Zn in direct influence area at Ansim Briquette Fuel Complex were $0.0008{\pm}0.0004{\mu}g/Sm^3$, $0.0141{\pm}0.0163{\mu}g/Sm^3$, $0.0248{\pm}0.0059{\mu}g/Sm^3$, $0.0026{\pm}0.0011{\mu}g/Sm^3$, $0.0272{\pm}0.0084{\mu}g/Sm^3$, $0.4855{\pm}0.1862{\mu}g/Sm^3$, and $0.3068{\pm}0.0631{\mu}g/Sm^3$, respectively. In particularly, the average concentrations for Cd, Cr, Mn, Ni, Pb, Fe, and Zn in direct influence area at Ansim Briquette Fuel Complex were 1.9, 3.6, 2.1, 1.9, 1.4, 2.6, and 1.2 times higher than reference area, respectively. The continuous monitoring and management were required for some heavy metals such as Cr and Ni. Moreover, the average concentration in winter for particulate matter in direct influence area at Ansim Briquette Fuel Complex were generally higher than concentrations in summer and autumn. Also, average concentrations for TSP, $PM_{10}$, and $PM_{2.5}$ were from 1.5 to 2.0 times, 1.2 to 1.8 times, and 1.1 to 2.3 times higher than reference area, respectively. In results for seasonal atmospheric environment, TSP, $PM_{10}$, $PM_{2.5}$, and heavy metal concentrations in direct influence area were higher than reference area. Especially, the concentrations in C station were a high level in comparison with other area. Conclusions: In the results, some particulate matters and heavy metals were relatively high concentration, in order to understand the environmental pollution level and health effect in surrounding area at Ansim Briquette Fuel Complex. The concentration of some heavy metals emitted from direct influence area at Ansim Briquette Fuel Complex were relatively higher than reference area. In particular, average concentration for heavy metals in this study were higher than average concentrations in air quality monitoring station for heavy metal for 7 years in Deagu metropolitan region. Especially, the residents near Ansim Briquette Fuel Complex may be exposed to the pollutants(TSP, $PM_{10}$, $PM_{2.5}$, and heavy metals, etc) emitted from the factories in Ansim Briquette Fuel Complex.

The Establishment of Seongjusa Temple and the Production of Iron Buddhas (성주사 창건과 철불 조성 연구)

  • Kang Kunwoo
    • MISULJARYO - National Museum of Korea Art Journal
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    • v.104
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    • pp.10-39
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    • 2023
  • Seongjusa Temple was founded in Boryeong in Chungcheongnam-do Province by Monk Muyeom (800-888), better known as Nanghye Hwasang. After returning from studying in China, Muyeom stayed in the Silla capital city of Gyeongju for a period. He later settled in a temple that was managed by the descendants of Kim In-mun (629-694). He then restored a burned-out temple and opened it in 847 as a Seon (Zen) temple named Seongjusa. It prospered and grew to become a large-scale temple with several halls within its domains. The influence of Seongjusa in the region can be seen in the Historical Record of Seongjusa Temple on Sungamsan Mountain, which relates that there were seventy-three rooms within the domains of the temple. What is most notable in the record is that the temple is referred to as "栴檀林九間," which means either "a structure with nine rooms built with Chinese juniper wood" or "a place that houses Chinese juniper wood and has nine rooms." Regardless of the interpretation, Seongjusa Temple had a large amount of juniper wood. Around this time, the term "juniper" referred to the olibanum tree (Boswellia sacra) native to the islands of Java and Sumatra in Southeast Asia. It is presumed that at some point after the death of Jang Bogo, the maritime forces that controlled the southwestern coast of Korea may have acquired a large amount of Southeast Asian olibanum wood and offered it to Seongjusa Temple. During the reign of King Munseong, Kim Yang (808-857) patronized Seongjusa Temple and its head monk Muyeom, who enjoyed a lofty reputation in the region. He sought to strengthen his own position as a member of the royal lineage of King Muyeol and create a bridge between the royal family and Seongjusan Buddhist sect. The court of King Wonseong designated Seongjusa Temple as a regional base for the support of royal authority in an area where anti-royal sentiment remained strong. Monk Muyeom is believed to have created an iron Buddha to protect the temple, enlighten the people, and promote regional stability. Given that the Seongjusa community had expanded to include more than 2,000 followers, the iron Buddha at Seongjusa Temple would have been perceived as an image that rallied the local residents. It is assumed that there were two iron Buddhas at Seongjusa Temple. The surviving parts of these Buddhas and the size of their pedestals suggest that they were respectively enshrined in the Geumdang Main Hall and the Samcheonbuljeon Hall of Three Thousand Buddhas. It is presumed that the first iron Buddha in Geumdang was a large statue over two meters in height and the second one was medium-sized with the height over one meter. The Historical Record of Seongjusa Temple on Sungamsan Mountain contains the phrase "改創選法堂五層重閣" which indicates that a multistoried Geumdang was newly built to enshrine a large Buddha sculpture like the first iron Buddha when Seongjusa Temple was founded. Also, according to the Stele of Seongjusa Temple and the surviving finger fragments, the first Buddha was making the fear-not and wish-granting (abhayavarada) mudras. The main Buddha of Seongjusa Temple is possibly Nosana Buddha, just like the main Buddhas at the contemporaneous temples Silsangsa, Borimsa, and Samhwasa. Given that Monk Muyeom studied Hwaeom teachings in his early years and received royal patronage upon his return, it is believed that the retro tendencies of the Hwaeom school, centered on the royal family of the Silla Dynasty, were reflected in Seongjusa temple.

Thermal Effluent Effects of Domestic Sewage and Industrial Wastewater on the Water Quality of Three Small Streams (Eung, Chiljang and Buso) during the Winter Season, Korea (동계 저온기의 소하천 수질에 미치는 하·폐수의 온배수 영향)

  • Soon-Jin, Hwang;Jeon, Gyeonghye;Eum, Hyun Soo;Kim, Nan-Young;Shin, Jae-Ki
    • Korean Journal of Ecology and Environment
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    • v.50 no.2
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    • pp.238-253
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    • 2017
  • The sewage and wastewater (SAW) are a well-known major source of eutrophication and greentide in freshwaters and also a potential source of thermal pollution; however, there were few approaches to thermal effluent of SAW in Korea. This study was performed to understand the behavioral dynamics of the thermal effluents and their effects on the water quality of the connected streams during winter season, considering domestic sewage, industrial wastewater and hot spring wastewater from December 2015 to February 2016. Sampling stations were selected the upstream, the outlet of SAW, and the downstream in each connected stream, and the water temperature change was monitored toward the downstream from the discharging point of SAW. The temperature effect and its range of SAW on the stream were dependent not only on the effluent temperature and quantity but also on the local air temperature, water temperature and stream discharge. The SAW effects on the stream water temperature were observed with temperature increase by $2.1{\sim}5.8^{\circ}C$ in the range of 1.0 to 5.5 km downstream. Temperature effect was the greatest in the hot spring wastewater despite of small amount of effluent. The SAW was not only related to temperature but also to the increase of organic matter and nutrients in the connected stream. The industrial wastewater effluent was discharged with high concentration of nitrogen, while the hot spring wastewater was high in both phosphorus and nitrogen. The difference between these cases was due to with and without chemical T-P treatment in the industrial and the hot spring wastewater, respectively. The chlorophyll-a content of the attached algae was high at the outlet of SAW and the downstream reach, mostly in eutrophic level. These ecological results were presumably due to the high water temperature and phosphorus concentration in the stream brought by the thermal effluents of SAW. These results suggest that high temperature of the SAW needs to be emphasized when evaluating its effects on the stream water quality (water temperature, fertility) through a systematized spatial and temporal investigation.

Variations of Agronomic Characteristics of Collected Coix lachryma-jobi Species (국내 율무 수집종의 특성변이)

  • Yi, Eun-Seob;Kim, Hee-Dong;Kim, Sung-Kee;Yoon, Seong-Tak
    • Korean Journal of Medicinal Crop Science
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    • v.12 no.4
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    • pp.279-284
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    • 2004
  • This experiment was conducted to evaluate on agronomic traits of Korean local adlay (Coix lachryma L.) germplasm, 281 cultivars (lines). The largest collected cultivars was from Kyungsangbukdo (56 cultivars), and the next was in the order of Cheonlabukdo (48 cultivars), Kyungsangnamdo (44 cultivars), Kyunggido (39 cultivars) Chungcheongnamdo (23 cultivars), Kangwondo (23 cultivars), Cheonlanamdo (17 cultivars), and Chungcheongbukdo (16 cultivars) in distribution of collected region for 281 cultivars. In the growth stages, days to emergence from seeding were required $16.4{\pm}2.03$ days, days to heading from emergence was required $73.6{\pm}5.87$ days, days to ripening from heading was required $52.3{\pm}4.91$ days and cultivation period was required $142.5{\pm}5.87$ days. Culm length was $210.3{\pm}16.39$ cm, no. of tiller per plant was $10.4{\pm}2.13$, culm diameter was $11.7{\pm}1.09$ mm, fruiting position was $4.6{\pm}0.82$ node, no. of main culm node was $11.1{\pm}0.78$, degree of lodging was $5.3{\pm}3.42$ and severity of leaf blight was $56.1{\pm}0.78$ in the growth characteristics of the germplasm. In the yield of component, no. of grains per $m^2$ was $5,938{\pm}2,152$, percentage of ripening was $67.7{\pm}33.12$, 1,000 grains weight was $123.8{\pm}33.76$ g and grain weight was $473.0{\pm}207.90$ g. Grain weight was correlates significantly positively with no. of main culm node, percentage of ripening and no. of grains per $m^2$ among agronomic traits. Correlation coefficient between grain weight and 1,000 grain weight was positive, while grain weight and severity of leaf blight was significantly negative. Correlation coefficient between grain weight and days to ripening from heading was significant negatively.

Assessment of Metabolic Impairment in Alzheimer's Disease with [$^{18}F$]FDG PET: Validity and Role of Simplified Tissue Radioactivity Ratio Analysis (알쯔하이머병에서 양전자방출단층촬영을 이용한 국소뇌포도당대사의 변화에 관한 연구)

  • Kim, Sang-Eun;Na Duk-Lyul;Lee, Jeong-Rim;Choi, Yong;Lee, Kyung-Han;Choe Yearn-Seong;Kim, Doh-Kwan;Kim, Byung-Tae;Lee, Kwang-Ho;Kim, Seung-Tai P.
    • The Korean Journal of Nuclear Medicine
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    • v.30 no.3
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    • pp.299-314
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    • 1996
  • The purpose of the present study was to validate the use of tissue radioactivity ratios instead of regional metabolic rates for the assessment of regional metabolic changes in Alzheimer's disease(AD) with [$^{18}F$]FDG PET and to examine the correlation of ratio indices with the severity of cognitive impairment in AD. Thirty-seven AD Patients(age $68{\pm}9 yrs$, $mean{\pm}s.d.$; 36 probable and 1 definite AD), 28 patients with dementia of non-Alzheimer type(age $66{\pm}7 yrs$), and 17 healthy controls(age $66{\pm}4 yrs$) underwent [$^{18}F$]FDG PET imaging. Two simplified radioactivity ratio indices were calculated from 37-66 min image: region-to-cerebellar radioactivity ratio(RCR) and a composite radioactivity ratio(a ratio of radioactivity in the most typically affected regions over the least typically affected regions: CRR). Local cerebral metabolic rate for glucose(LCMRglu) was also measured using a three-compartment, five-parameter tracer kinetic model. The ratio indices were significantly lower in AD patients than in controls(RCR in temporoparietal cortex, $0.949{\pm}0.136$ vs. $1.238{\pm}0.129$, p=0.0004; RCR in frontal cortex, $1.027{\pm}0.128$ vs. $1.361{\pm}0.151$, p<0.0001; CRR, $0.886{\pm}0.096$ vs. $1.032{\pm}0.042$. p=0.0024). On the RCR analysis, 86% of AD patients showed a pattern of bilateral temporoparietal hypometabolism with or without frontal involvement; hypometabolism was unilateral in 11% of the patients. When bilateral temporoparietal hypometabolism was considered to be suggestive of AD, the sensitivity and specificity of the RCR analysis for the differential diagnosis of AD were 86% and 73%, respectively. The RCR was correlated significantly with the macroparameter K [$K_1k_3/(k_2+k_3)$] (r=0.775, p<0.0001) and LCMRglu(r=0.633, p=0.0002) measured using the kinetic model. In patients with AD, both average RCR of cortical association areas and CRR were correlated with Mini-Mental Status Examination(r=0.565, p=0.0145; r=0.642, p=0.0031, respectively), Clinical Dementia Rating(r=-0.576, p=0.0124; r=-0.591, p=0.0077), and total score of Mattis Dementia Rating Scale (r=0.574, p=0.0648; r=0.737, p=0.0096). There were also significant correlations between memory and language impairments and corresponding regional RCRs. The results suggest that the [$^{18}F$]FDG PET ratio indices, RCR and CRR, reflect global and regional metabolic rates and correlate with the severity of cognitive impairment in AD. The simplified ratio analysis may be clinically useful for the differential diagnosis and serial monitoring of the disease.

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A Study on Visitor Satisfaction for Bukhansan Dulegil (북한산 둘레길 이용객 만족도에 관한 연구)

  • Cho, Woo-Hyun;Yun, Hui-Jae;Im, Seung-Bin
    • Journal of the Korean Institute of Landscape Architecture
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    • v.39 no.4
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    • pp.60-73
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    • 2011
  • Since Jeju Ollegil opened in September 2007 and attracted the sensation of popularity throughout the country, the interest in 'Walking Trails' has increased, and the central ministries and the local governments composite and assign various 'Walking Trails'. Walking trails are not tours on which people go to see one spot and move to another spot by vehicle, but a long linear journey that leads people to see, to feel and to experience a region's landscape and culture while walking on the trail. 'Walking Trails' are efficient routes to discover and to use a former way and to link the various ecological regions' histories and cultural resources, so it is most important to select a route. Although the routes were selected by considering the various planning factors and giving each route a specified theme, some problems like the inconvenience of visitors caused by lack of facilities have occurred. After designation and construction of the trails, they were not properly evaluated by visitors. Therefore, it is the purpose of this study to suggest a better way to construct the trails by surveying visitor satisfaction and by analyzing the impact of planning a route on visitor satisfaction at Bukhansan Dulegil which was completed. For this study, with a questionnaire based on the literature review to identify the important planning factors for selecting a route, a survey was conducted on visitor satisfaction for each section and their intention to revisit and to recommend that trail. Based on the characteristics of each section that was identified in the field research, the trails were classified into five types and satisfaction of each type and each type was analyzed. In addition, analyzing the impact of planning factors on satisfaction, the impact of satisfaction on revisiting and recommending and visitors' perception of the theme, further improvement for better construction of the trail was presented. Satisfaction of sectors with strong natural elements was higher; 'walking comfort' was the highest planning factor affecting satisfaction. In addition, satisfaction was surveyed to have high influence on revisiting and recommending.