• Title/Summary/Keyword: Flat Spot

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Disease Incidences in Radish and Chinese Cabbage. I. Major Diseases in Radish and Chinese Cabbage grown in Alpine Areas in Jeonbug Province (고냉지단경기채소(무우. 배추) 및 평야지 추작채소단지에 발생하는 주요병해조사 I. 전북고냉지단경기 무우, 배추 주요병해)

  • So I.Y.;Lee S.H.;Kim H.M.;Lee W.H.
    • Korean journal of applied entomology
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    • v.20 no.3 s.48
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    • pp.135-145
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    • 1981
  • Vegetables including Chinese cabbage and radish have been grown in alpine areas such as Muju, Namweon, Jinan and Jangsu during the shortage period of vegetables. The incidence of various diseases, environmental factors such as temperatures and rainfalls, and aphid populations as virus vector were observed at 10-day intervals from July to September in those areas. Disease incidence showed no significant difference among locations. Major diseases in Chin ese cabbage were bacterial soft rot, white spot, downy mildew, mosaic virus, Alternaria leaf spot and Fusarium seedling blight. Major diseases in radish were virus, white rust, black rot, root rot, leaf spot and Fusarium seedling blight. Disease incidence reached peak on Aug. 20 with $27\%$ infection in radish and with $20\%$ infection in Chinese cabbage during the growing season, and declined thereafter. Percentage of infection in each growth stage showed $25\%$ at root thickening stage and $26\%$ at the harvest time in radish; and the head formation stage, $24\%$ at the harvest time. The data indicate that disease incidence in radish increased rapidly at late growing stage and progressively increased in Chinese cabbage Seedling blight caused by Fusarium sp. and root rot caused by Aphanomyces sp. were also observed in those areas. Cool and wet weather appeared to be favorable for disease incidences during the rainy period of growing season although average temperature was about $25^{\circ}C$. Populations of aphids were lower in the alpine vegetable growing area than that of flat areas. Aphids as virus vectors from total aphids collected were $73.5\%$ or 289 virus vectors /993 total aphids in Namweon and $18.1\%$ or 31 virus vectors/171 total aphids in Muju. The most prerevalent species of aphids was Myzus persicae Sulz.

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Overview of new developments in satellite geophysics in 'Earth system' research

  • Moon Wooil M.
    • 한국지구물리탐사학회:학술대회논문집
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    • 2004.06a
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    • pp.3-17
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    • 2004
  • Space-borne Earth observation technique is one of the most cost effective and rapidly advancing Earth science research tools today and the potential field and micro-wave radar applications have been leading the discipline. The traditional optical imaging systems including the well known Landsat, NOAA - AVHRR, SPOT, and IKONOS have steadily improved spatial imaging resolution but increasing cloud covers have the major deterrent. The new Earth observation satellites ENVISAT (launched on March 1 2002, specifically for Earth environment observation), ALOS (planned for launching in 2004 - 2005 period and ALOS stands for Advanced Land Observation Satellite), and RADARSAT-II (planned for launching in 2005) all have synthetic aperture radar (SAR) onboard, which all have partial or fully polarimetric imaging capabilities. These new types of polarimetric imaging radars with repeat orbit interferometric capabilities are opening up completely new possibilities in Earth system science research, in addition to the radar altimeter and scatterometer. The main advantage of a SAR system is the all weather imaging capability without Sun light and the newly developed interferometric capabilities, utilizing the phase information in SAR data further extends the observation capabilities of directional surface covers and neotectonic surface displacements. In addition, if one can utilize the newly available multiple frequency polarimetric information, the new generation of space-borne SAR systems is the future research tool for Earth observation and global environmental change monitoring. The potential field strength decreases as a function of the inverse square of the distance between the source and the observation point and geophysicists have traditionally been reluctant to make the potential field observation from any space-borne platforms. However, there have recently been a number of potential field missions such as ASTRID-2, Orsted, CHAMP, GRACE, GOCE. Of course these satellite sensors are most effective for low spatial resolution applications. For similar objects, AMPERE and NPOESS are being planned by the United States and France. The Earth science disciplines which utilize space-borne platforms most are the astronomy and atmospheric science. However in this talk we will focus our discussion on the solid Earth and physical oceanographic applications. The geodynamic applications actively being investigated from various space-borne platforms geological mapping, earthquake and volcano .elated tectonic deformation, generation of p.ecise digital elevation model (DEM), development of multi-temporal differential cross-track SAR interferometry, sea surface wind measurement, tidal flat geomorphology, sea surface wave dynamics, internal waves and high latitude cryogenics including sea ice problems.

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Utilization of LFWD for Compaction Management of Embankment in Expressway Construction (고속도로 건설 시 성토부 다짐관리를 위한 LFWD의 활용성)

  • Park, Yangheum;Jang, Ilyoung;Do, Jongnam
    • Journal of the Korean GEO-environmental Society
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    • v.22 no.3
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    • pp.45-51
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    • 2021
  • The evaluation of the degree of compaction of the embankment area, which accounts for most of highway earthworks, is generally performed by a flat plate loading test. The plate loading test is a traditional test method and has high reliability in the field. However, as reaction force equipment must be carried out and it takes about 40 minutes per site during the test, there may be limitations in managing the entire expanse of earthworks. Meanwhile, in order to overcome this, the Ministry of Land, Infrastructure and Transport proposed a simple method of evaluating the level of compactness in the provisional guidelines for compaction management of the packaging infrastructure in 2010. However, it has not been utilized at the highway construction site until now, 10 years later. Therefore, this study attempted to verify the utility of the compaction evaluation method using LFWD (Light Falling Weight Deflectometer) of the impact loading method among the test methods suggested in the provisional guideline. To this end, the correlation was derived by conducting a plate loading test and an LFWD test for each site property and compaction degree. As a result of the test, there was no consistency of test data in the ground with a relative compaction of 80% or less. However, it was confirmed that the correlation has a tendency to increase beyond that. If the test method or test equipment is improved to ensure the consistency of the test values of the impact loading method in the future, it will play a big role in solving the blind spot for compaction management in the earthworks.

Micro-CT System for Small Animal Imaging (소동물영상을 위한 마이크로 컴퓨터단층촬영장치)

  • Nam, Ki-Yong;Kim, Kyong-Woo;Kim, Jae-Hee;Son, Hyun-Hwa;Ryu, Jeong-Hyun;Kang, Seoung-Hoon;Chon, Kwon-Su;Park, Seong-Hoon;Yoon, Kwon-Ha
    • Progress in Medical Physics
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    • v.19 no.2
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    • pp.102-112
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    • 2008
  • We developed a high-resolution micro-CT system based on rotational gantry and flat-panel detector for live mouse imaging. This system is composed primarily of an x-ray source with micro-focal spot size, a CMOS (complementary metal oxide semiconductor) flat panel detector coupled with Csl (TI) (thallium-doped cesium iodide) scintillator, a linearly moving couch, a rotational gantry coupled with positioning encoder, and a parallel processing system for image data. This system was designed to be of the gantry-rotation type which has several advantages in obtaining CT images of live mice, namely, the relative ease of minimizing the motion artifact of the mice and the capability of administering respiratory anesthesia during scanning. We evaluated the spatial resolution, image contrast, and uniformity of the CT system using CT phantoms. As the results, the spatial resolution of the system was approximately the 11.3 cycles/mm at 10% of the MTF curve, and the radiation dose to the mice was 81.5 mGy. The minimal resolving contrast was found to be less than 46 CT numbers on low-contrast phantom imaging test. We found that the image non-uniformity was approximately 70 CT numbers at a voxel size of ${\sim}55{\times}55{\times}X100\;{\mu}^3$. We present the image test results of the skull and lung, and body of the live mice.

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Experimental Study for Phase-contrast X-ray Imaging Based on a Single Antiscatter Grid and a Polychromatic X-ray Source (단일 비산란 그리드 및 다색광 x-선원 기반 위상대조 x-선 영상화 실험 연구)

  • Park, Yeonok;Cho, Hyosung;Lim, Hyunwoo;Je, Uikyu;Park, Chulkyu;Cho, Heemoon;Kim, Kyuseok;Kim, Guna;Park, Soyoung
    • Progress in Medical Physics
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    • v.26 no.4
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    • pp.215-222
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    • 2015
  • In this work, we performed a proof-of-concept experiment for phase-contrast x-ray imaging (PCXI) based on a single antiscatter grid and a polychromatic x-ray source. We established a table-top setup which consists of a focused-linear grid having a strip density of 200 lines/inch, a microfocus x-ray tube having a focal-spot size of about $5{\mu}m$, and a CMOS-type flat-panel detector having a pixel size of $48{\mu}m$. By using our prototype PCXI system and the Fourier demodulation technique, we successfully obtained attenuation, scattering, and differential phase-contrast images of improved visibility from the raw images of several selected samples at x-ray tube conditions of $90kV_p$ and 0.1 mAs. Further, fusion image (e.g., the attenuation+the scattering) may have an advantage in displaying details of the sample's structures that are not clearly visible in the conventional attenuation image. Our experimental results indicate that single-grid-based approach seems a useful method for PCXI with great simplicity and minimal requirements on the setup alignment.

Assumptions on the Location of Changokbyeong and Saahm Park Soon's Garden Remains (창옥병(蒼玉屛)의 위치 비정(比定) 및 사암(思菴) 박순(朴淳)의 정원유적 연구)

  • Rho, Jae-Hyun;Park, Joo-Sung;Choi, Jong-Hee
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.34 no.4
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    • pp.37-50
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    • 2016
  • Recognizing the problem of fallacy in geographical name of Changokbyeong(蒼玉屛), assumption has been made on the location of Changokbyeong through literature research on antique maps, ancient paintings, and old prose, through field survey on rock inscriptions and landscape characteristics, and through interviews with local people. Furthermore, Baegyeonwa, the Cuckoo Hut, and Iyangjung(二養亭), an annex to the cottage, both of which were managed by Saahm Park Soon(思菴 朴淳), the Subject of Jouissance, were studied in depth with emphasis on the spatial structure as well as special features of the area as a garden. The major findings are as follows: Changokbyeong is a spatial threshold that imparts a sense of unity with Okbyeng seowon(玉屛書院) and indeed Changokbyeong is presumed to have been the frontal river terrace of Okbyeng seowon according to the analysis of antique maps and rock inscriptions. This ancient location and the Ogari Stone Wall, the present day Changokbyeong, are only 460m away so that both areas are considered as falling under the influence of Changokbyeong landscape. The expression "Changokbyeong Geupsangeum(蒼玉屛及散襟)" written in an old prose tells us that the high rock wall with Sangeumdae inscribed on the rock might be the rock wall of Changokbyeong. In addition, while not a single rock inscription has been found on the Ogari Stone Wall, 11 rock inscriptions designed and ordered by Saahm Park Soon, the Subject of Jouissance, are found on every corner of the high rock wall standing in front of Okbyeng seowon, 8 of those 11 being place names and recitative poems(known as Jeyeongsi: 題詠詩) in close formation resembling the handwritings in a little notebook. This provides a strong evidence for assuming the location of Changokbyeong to be the frontal river terrace of Okbyeng seowon. The "Songgyun Jeoljo Suwol Jeongshin(松筠節調 水月精神)" rock inscription on Changokbyeong should be considered as the stamping ground and as the symbolic language of Changokbyeong that bears the high character and nobility of the Subject of Jouissance, Saahm Park Soon. The inscription should also be recognized as the handwritings of Wooahm Song Si-Yeol(尤庵 宋時烈) correcting the misconceptions that persisted until today. Meanwhile, the garden remains of Saahm's Changokbyeong are composed of four sites: Sangeumdae-Sugyeongdae-Cheonghakdae-Baekhakdae from the left. At the back of Sangeumdae, there is the original house, the Baegyeonwa(拜鵑窩), and on the fantastically shaped stone wall at the left of Baekhakdae, there is the annex, the Iyangjung, together creating a landscape composition that overlooks the splendor of the Ogari Stone Wall. The Iyangjung is located on the highest spot to the left of the four sites, and it is believed to have been a little outhouse and library for Saahm which remains to the present day as a place where Saahm's character can be felt. The drinking plates[窪樽] made of rock that are affectionately arranged on the broad flat rock in front of Iyangjung is part of the garden remains that reflects the artistic taste of Saahm regarding the drinking culture at the time.

A Study on the Architectural Characteristic Jang-Dae of Castle in the Joseon Dynasty (조선시대 성곽 장대의 건축특성에 관한 연구)

  • Kim, Ki-hyeon;Chang, Hun-duck
    • Korean Journal of Heritage: History & Science
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    • v.48 no.2
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    • pp.120-141
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    • 2015
  • This paper is a preliminary study of architectural characteristics of Jangdae (general's podium), which shows one of the technical changes in fortification of Joseon Dynasty. As a facility for commands of generals and training for officers and men, it was located inside a fortress. Although it is not certain when the first Jangdae was built, the number of them dramatically increased around 18th century. Since the top priority function of the Jangdae was the prospect, it was installed at the hilly spot with open architecture. In addition, the open structure of Eupseong fortress towers on the riverside banks could simultaneously offer the functions as viewing around and Jangdae. Since Jangdae was also a place for military drills and reviews of soldiers, a wide podium was positioned at the front to muster the soldiers. This feature was standardized in the space organization of Jangdae in Joseon, and a mere podium was installed unless the topographic restrictions allows enough space. On the other hand, as a place for a commander, the hierarchy of the Jangdae was revealed through a variety of architectural characteristics. The hierarchy was assigned to the commander's space through the altitude difference, and diverse ornaments were added to show a sense of class. The floor plan of the Jangdae building can be largely categorized into rectangle and square, and the typical sizes of the former are $5{\times}4$ Kans (traditional measuring unit between two columns) and $3{\times}2$ Kans. Out of these two types, buildings of $5{\times}4$ Kans were found in flat land and eupseong fortresses with large space, and the relatively smaller ones of $3{\times}2$ Kans in mountain fortresses. All buildings of square floor plan had $3{\times}3$ Kans style, and the center Kan was twice wider than the side Kan to make the central space wide. It seems that the purpose was to secure the interior space of the upper story because the center Kan accounts for the floor area of the upper story. Some Jangdae's had internal story to form overhead space. The multi-roofed tower style with eaves attached to the upper and lower story is found exclusively in Jangdae. The buildings shows the Onkanmulim style which extends Naejinju (inner column) of the lower story to be the Byeonju (outer column) of the upper story, and the log-framed floor in the upper floor was structured by inserting the Changbang (connecting beam) between the Naejinju's and joining the log frames. In addition, the towers in eupseong fortresses had log-framed floor in the upper floor by setting up the high Nuhaju (column underneath a roof) and joining Cheongbang to the upper part of the column while it cannot be regarded as multi-roofed because only the upper part has a roof.

A Diachronic Study on Historical and Cultural Landscape of Songhyeon-dong, Seoul (서울 송현동(松峴洞) 일원 역사문화경관의 통시적 연구)

  • Kang, Jae-Ung;So, Hyun-Su
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.39 no.4
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    • pp.85-98
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    • 2021
  • In accordance with planning to construct culture park on Songhyeon-dong (district) near Gyeongbokgung Palace, This study analyzed literature and drawings from the early Joseon Dynasty to today for the district, known as 'Songhyeon (pine hill)' to identify historical and cultural landscapes during essential times. The following are the results; First, the owners of significant lots were identified, and land use and landscape components were extracted for a diachronic examination of the landscape of the whole area of Songhyeon-dong. Songhyeon district had been regarded as the 'Inner Blue Dragon (Spot) of Gyeongbokgung Palace' in terms of geomancy since the foundation of Joseon in 1392 in that the government created and managed a 'pine forest' in the district. A state warehouse called 'bungam' was constructed, and small fruit stores, 'ujeon,' opened due to the complete reformation and urban planning led by King Taejong in 1410. From the 19th century, mansions of the upper class, such as 'Gaseonggak', 'Changnyeongwuigung' and 'Byeoksugeosajeong' were in the district. A prominent official residential complex called 'Sigeun Sataek' was constructed in 1919 after Chosen Siksan Bank purchased the site. Later, it was transferred to America in 1948 and used as the 'US Embassy Staff Quarters'. Second, the changes in the site view, associated with the aspects of society by the times, were examined by estimating the location and the time the landscape components lasted in each period extracted and identifying the physical entity. The pine forest, regarded as the 'Inner Blue Dragon' that guards the left side of the palace within the geomantic world view, was located in the highlands in the west of the site. In the same period, the flat area in the east was regarded as the 'commoner's district', the streets adjacent to various government facilities and the market, packed with people from different walks of life. From the 19th century, the gardens of the aristocrats of the capital city were created in the pine forest, turning the place into the forest in the middle of the city. The whole area of Songhyeon-dong, which existed as a large lot in the city center for a long time, was developed by Japanese imperialists in the 20th century based on the concept of 'Ideal Healthy Land,' which interrupted the placeness of Songhyeon-dong that had adhered to the traditional geomatic view of the Joseon Dynasty.

A Study on the Present Situation, Management Analysis, and Future Prospect of the Ornamental Tree Cultivation with respect to Environmental Improvement (환경개선(環境改善)을 위한 녹화수목재배(綠化樹木裁培)의 현황(現況) 및 경영분석(經營分析)과 전망(展望))

  • Park, Tai Sik;Kim, Tae Wook
    • Journal of Korean Society of Forest Science
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    • v.34 no.1
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    • pp.31-46
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    • 1977
  • The study was made to give some helpful information for policy-making on ornamental tree cultivation by doing a survey on general situations, management analysis, and future prospects of the ornamental tree growing. The study was carried out through literature studies related to the subject, questionaire surveys, and on-the-spot investigation. The questionaire surveys could be divided into two parts: pre-questionaire survey and main-questionaire survey. In the pre-questionaire survey, the researchers intended to identify the total number of ornamental tree growers, cultivation areas in size and their locations. The questionaires were sent to each town and county administration authorities, forest cooperatives, and related organizations through-out the nation. The main-questionaires were prepared for detailed study and the questionaires were sent to 200 tree growers selected by option by taking considerations of the number of tree growers and the size of cultivating areas in regions. The main findings and some information obtained in the survey were as follows: 1. The total land for ornamental tree growing was amounted to 1,873.02 hectares and the number of cultivators was totaled to 2,717. 2. The main occupations of the ornamental tree growers were found in horticulture (41.9%), agronomy (25.9%), officialdom (11.3%), animal husbandry (6.5%), business circle(4.8%), and forestry (3.2%) in sequence. 3. The ornamental trees were cultivated mostly upperland (54.8), forest land (19.4%), rice paddy (11.3%) and others. 4. The educational training of the tree growers seemed quite high. The results of the survey indicated that a large number of tree growers was occupied by college graduates (38.7%), and then high school graduates (34.7%), middle school graduates (12.9%) in order. 5. The tree farming was undertaken as a side-job (41.9%) rather than main-job (23.4%), but a few of respondents rated as subsidiary-job (18.6%). 6. The management status classified by the rate of hired labors used was likely to belong to three categories: independant enterprise management (41.9%); half independant management (31.5%); and self-management (32.4%). 7. The majority of the tree growers sold their products to the consumers through middle-man channel (48.4%), or directly to the house-holder and detailers (13.7%), but a few of the respondents answered that they disposed of their products by bidding (11.2%) or by direct selling to the contractors (4.8%). 8. The channel cf marketing seemed somewhat complicated. The results of the survey were as: (1) producers ${\rightarrow}$consumers (22.6%) (2) producers ${\rightarrow}$field middle-men${\rightarrow}$consumers (33.1%) (3) producers ${\rightarrow}$field middle-men${\rightarrow}$first stage brokers${\rightarrow}$consumers (15.3%) (4) producers ${\rightarrow}$field middle-men${\rightarrow}$second stage middle-men${\rightarrow}$brokers${\rightarrow}$consumers (5.7%) (5) producers${\rightarrow}$field middle-men${\rightarrow}$third stage middle-men${\rightarrow}$second stage middlemen${\rightarrow}$brokers${\rightarrow}$consumers (4.8%) 9. It was responded that the margin for each stage of middle-men or brokers was assumed to be 30-50%(33.1%), 20-30%(32.3%), 50-100%(9.7%), and 100-200%(2.4%) in sequence. 10. The difference between the delivery price of consumers and field selling price of the producers seemed quite large. Majority of producers responded that they received half a price compared to the consumer's prices. 11. About two thirds of the respondents opposed to the measure of "Law on Preservation and Utilization of Agricultural Land" in which says that all the ornamental trees grown on flat agricultural lands less than 8 degrees in slope must be transplanted within three years to other places more than 8 degrees in slope. 12. The tree growers said that they have paid rather high land taxes than they ought to pay (38.7%), but come responded that land tax seemed to be appropriate (15.3%), and half of the respondents answered "not known". 13. The measures for the standardization of ornamental trees by size were backed up by a large number of respondents (57.3%), but one third of the respondents showed negative answer (29.8%). 14. About half of the respondents favored the systematic marketing through organization such as forest cooperatives (54%), but quite a few respondents opposed to organizing the systematic marketing channel (36.3%). 15. The necessary measures for permission in ornamental tree cultivation was rejected by a large number of respondents (49.2%) than those of favored (43.6%).

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