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A Mineralogical and Gemological Studies for the Enhancement of Tanzania Ruby by Heat Treatment (탄자니아산 루비의 열처리에 의한 보석·광물학적 품질개선 연구)

  • Kim, Seon-Ok;Wang, Sookyun;Oh, Sul-Mi;Park, Hee Yul;Park, Maeng-Eon
    • Economic and Environmental Geology
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    • v.47 no.6
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    • pp.563-569
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    • 2014
  • Ruby is one of the most favor colored gem, for beautiful red tone, be high in scarcity value. However, rubies with high quality are produced in restricted regions, such as in Thailand, Sri Lanka, Myanmar, and Tanzania etc., and they have been gradually exhausted by mining for a long period. Therefore, improving qualities of low level rubies with various treatments is arising an alternative way to obtain better rubies. Gemological and mineralogical properties of the natural ruby from Tanzanian were studied with heat treatments. Those characteristics were compared between only heat and adding flux materials under heating. Tanzanian raw rubies were applied a heat treatment ($1,600^{\circ}C$ for 6 hours). However, chromameter and UV-Vis analyses found that a simple heat treatment is inappropriated for the Tanzanian ruby. Although $Cr^{3+}$ containing for red color in the ruby increased with heat treatment, the ruby displays dark medium red because of Fe in the ruby as a form of $Fe_2O_3$. The low transparency after heat treatment is attributed to the recrystallization of $SiO_2$ which has a low melting point. Chromameter confirmed adding Pb-containing flux under heating greatly improves the clarity and color of Tanzanian rubies with micro-fractures and cavities on the surface. EMPA results show that Pb as an additive fills the cavities and cracks on raw Tanzanian rubies during the heat treatment. As a rewult of it, the quality of the Tanzanian ruby raw dramatically improved. These results indicate that the heat treatment with an additive (Pb in this study) is an effective way to obtain better quality of the Tanzanian ruby. Consequently, this study suggests a suitable method to improve the properties of the Tanzanina ruby. The result of this study would provide useful information to upgrade the qualities of similar gem stones such as corundum and sapphire.

A Study on the Blood-Letting Therapy in Elementary Questions (("황제내경소문(黃帝內經素問)" 중(中) 사혈(瀉血)에 관한 연구(硏究))

  • Lee, Jun-Geun
    • Journal of the Korean Institute of Oriental Medical Informatics
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    • v.14 no.1
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    • pp.19-42
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    • 2008
  • Blood-Letting Therapy is a rational and ecological medical treatment by which we can heal most of the diseases by removing the static blood which precipitates in the blood vessel and blocks the flowing of blood. And the static blood is the generic term for the injurious, bad, dead and precipitated blood which is blocked the capillary vessel. The Yellow Emperor's Canon of Internal Medicine says that "the patient is treated with drugs internally and stone acupuncture externally. "In the old texts, the blood-letting therapy is mentioned as blood-letting, network vessel pricking, bloodletting, pricking, and arousing pulses etc and it is noted down as the method of network vessel pricking in 'On the Application of Needles' of Spiritual Pivot. Nine-pricking therapy, twelve-pricking therapy and five-pricking therapy are recorded in the methods of network vessel pricking and among them, the method of squeezing blood after pricking the affected part is explained as the network vessel pricking. There are four methods of network vessel pricking, pricking, picking, cluster needling and scatter-pricking and they are fluidly applied to the various symptoms of diseases. In 'On Discriminative Treating for Patients of Different Regions' in Elementary Questions, Ki-baek emphasizes "most of the local people, there are black in skin and loose in striate, and their diseases are mostly of carbuncle kind. It is suitable to treat the disease with stone therapy to prick with stone, so the stone therapy is transmitted from the east. "And in 'On the Corresponding Relation Between the Eum and Yang of Man and All Things' in Elementary Questions, when the Emperor asked Ki-Back, he answered "sthenia means the sthenia of evil, and deficiency means the deficiency of healthy energy. When the blood is sthenic, the evil should be discharged by pricking when out letting the blood; deficiency of vital energy is the asthenia of channels and network vessels, so the energy should drain from the channel which is not deficient, to replenish. "And in this case we can use the methods of 'Breaking out the static bloods', 'driving out the static bloods', blood-letting'. With this we can infer that the blood-letting therapy is made use of the important medical treatments from the ancient times. Especially in referring to the principles of treatment in The Yellow Emperor's Canon of Internal Medicine, it mostly alluded to acupuncture therapies and only eleven times to medicinal treatments. This is to verify that the blood-letting therapy formed the foundation of the medical art. In Dong's Therapy of Acupuncture-Moxibustion and Bloodletting, Dong Kyeong-Chang gave emphasis on the points that there must be extravasated bloods without exception in the serious illnesses which is old, unnatural, accompanying acute pains and so we can revive our body‘s sprit by circulating 'gi' and static blood piled up in the network vessel, regulating the weakness and strength, and controling the disharmony of the internal organs. The blood-letting therapy has effect on the orifice in emergency, such as fore draining, freeing network vessels, harmonizing gi and blood, relieving pain, dispersing swelling and concretion, sedation, resolving toxin as well as strengthening the heart, relieving itching. So it has distinguished effect on all kinds of medical treatment to the modern people. But by the change of social customs and the confucianism of confucius - it is widely spread on the period of North and South Dynasties, 'Wi' and 'Jin' in china and the period of the Three States in korea - The blood-letting therapy which was regarded as the most important medicinal treatment withered rapidly. And Confucius accentuated the importance of our body and all its members, loyalty and filial piety and banned any damage of our body under no circumstances. As a result of it, the therapy of blood-letting had a rapid decrease and barely kept itself in existence in both countries. What is worse, at the period of Japanese colonial rule of korea and our nation's founding of early stage, it has been withered by the high-handed policy to change Oriental Medicine into modern medical science. So the therapy of blood-letting barely kept itself in existence in some Buddhist temples. Another case, it has handed down as a old-fashioned quick fix in folk remedies. But all kinds of the contamination of heavy metals and the misuses of antibiotics are widely spread nowadays, which increased diseases of adult people and incurable diseases as modern society unavoidably made its way into a highly industrial society. To make us more miserable, the western medical science - the antibiotics and surgical operation medical science - already reveals itself into a limit. The necessity of a new medical science which can give a security to the patients who are suffering from the diseases of adult people and the incurable diseases is especially come into the force nowadays. In view of the results after bibliographically studying on the blood-letting Therapy in Elementary Questions of the Yellow Emperor's Canon of Internal Medicine, the blood-letting therapy has acted for the important Oriental medicinal science and has been clarified the prominent effects on the diseases of adult people and the incurable diseases. So it is regarded as an appropriate thing that we lay out a determined theory of the blood-letting therapy and of course prevent the unwanted side effects from inappropriate medicinal treatments, and make full use of clinic by elevating the curative value and that we win back our self-respect of medical treatment which is dominated from the western medical science and ultimately contribute to national medical welfare.

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Dose Distribution According to the Tissue Composition Using Wedge Filter by Radiochromic Film (쐐기필터 사용 시 레디오크로믹 필름을 이용한 조직에 따른 선량분포 연구)

  • Kim, Yon-Lae;Lee, Jeong-Woo;Park, Byung-Moon;Jung, Jae-Yong;Park, Ji-Yeon;Suh, Tae-Suk
    • Journal of radiological science and technology
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    • v.35 no.2
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    • pp.157-164
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    • 2012
  • The purpose of this study is to analyze the dose distribution when wedge filter is used in the various tissue electron density materials. The dose distribution was assessed that the enhanced dynamic wedge filter and physical wedge filter were used in the solid water phantom, cork phantom, and air cavity. The film dosimetry was suitable simple to measure 2D dose distribution. Therefore, the radiochromic films (Gafchromic EBT2, ISP, NJ, USA) were selected to measure and to analyze the dose distributions. A linear accelerator using 6 MV photon were irradiated to field size of $10{\times}10cm^2$ with 400 MUs. The dose distributions of EBT2 films were analyzed the in-field area and penumbra regions by using dose analysis program. In the dose distributions of wedge field, the dose from a physical wedge was higher than that from a dynamic wedge at the same electron density materials. A dose distributions of wedge type in the solid water phantom and the cork phantom were in agreements with 2%. However, the dose distribution in air cavity showed the large difference with those in the solid water phantom or cork phantom dose distributions. Dose distribution of wedge field in air cavity was not shown the wedge effect. The penumbra width, out of the field of thick and thin, was observed larger from 1 cm to 2 cm at the thick end. The penumbra of physical wedge filter was much larger average 6% than the dynamic wedge filter. If the physical wedge filter is used, the dose was increased to effect the scatter that interacted with photon and physical wedge. In the case of difference in electron like the soft tissue, lung, and air, the transmission, absorption, and scattering were changed in the medium at high energy photon. Therefore, the treatment at the difference electron density should be inhomogeneity correction in treatment planning system.

Present Status and Future Prospect on Fishing Industry in North Korea (북한수산업(北韓水產業)의 현황(現況)과 전망(展望))

  • Lee, Byoung-Gee;Kim, Jin-Kun;Choe, Jong-Hwa
    • Journal of Fisheries and Marine Sciences Education
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    • v.3 no.2
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    • pp.73-82
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    • 1991
  • In recent years, the communication and the trade between the Republic of Korea(South Korea) and the Communist bloc has been activated. The simultaneous entrance of South Korea and North Korea to the United Nations will accelerate the political dialogue and also the trade which is indirectly carried out through a third country at present will be turned into direct way. Fisheries products are also treated as one of the important trade goods and there is a hopeful prospect that the amount of trade will be steeply increased in the near future. Furthermore, there is a great possibility of development up to the joint utilization of fishing grounds or the joint investment in fisheries projects. Concerning such points, since it is very much important to understand the present status of fisheries in North Korea, the author made a study on this field as requested by the Board of Unification, and report a part of the study here. The prominent character of North Korea's ruling sea area is that the sea is completely separated into two regions-the East Sea Region and the West Sea Region-and no continuity exists between them. The East Sea Region locates in the fringe of the biggest fishing ground of the world-the North Pacific Ocean-and very rich in resources not only warm water fishes but also cold water fishes. Especially alaska pollack, Theragra chalcogramma, is caught abundantly in this region. Contrary to that, fishing activity in the West Sea Region seems to be interrupted in winter. Even though some valuable warm water fishes-yellow corvenia, Pseudosciaena manchurica, and hair tail, Trichiurus lepturus, and so forth-come to this region from spring to summer along the coast line of this region for spawning, and vigorous fishing activity is carried out. But the most of them migrate southward to the neighboring waters of Cheju Island for wintering from autumn to winter, and so the fishing activity in this region seems to be interrupted greatly during winter. The total number of fishing boats in North Korea is estimated at 36 thousand and the rate of mechnization at about 70% compared with 99 thousand and 78% in South Korea. North Korea proclaimed an exclusive economic zone of 200 nautical miles in 1977. Specific character of this zone is setting of military boundary zone, up to 50 miles from the base line in the East Sea Region and also it covers whole region of the economic zone in the West Sea Region. Especially in the East Sea Region she set up a straight base line which can not be permissible by the international law. North Korea's statistics on fisheries product has not been announced officially on account of her unique isolationism, but it can be estimated through several data procured. At the first, the amount of fisheries products in the North Korea is reported as about 1.7 million ${\frac{M}{T}}$ by Fisheries Statistics which issued by the FAO in 1987, but a North Korea's trade organization announced the amount as 3.5 million ${\frac{M}{T}}$ in 1988. The former seems to be underestimated and the latter must be an exaggeration. According to Chikuni, who is a Japanese worker for FAO, prepared the unofficial statistics based on the evidence which he collected through the fineries development plan of the FAO/UNDP, and estimated the mean amount between 1982 and 1984 was 2.4 million ${\frac{M}{T}}$ or so. The Board of Unification estimated on the basis of various factors that the amount was 2.2 million ${\frac{M}{T}}$ or so in 1987 and in 1988. This seems to be the most reasonable. To solve the chronic lack of foreign currency, North Korea makes effort on the development of fisheries, and has even aimed fisheries product at 11 million ${\frac{M}{T}}$ by 1993, but this target looks unrealistic under the present circumstances. Somehow, we can exploit her extreme policy which has gone so far as to establish such an excessive and impractical target. Nevertheless this will be helpful to promote the joint development of the fishery activity between South Korea and North Korea.

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Validation of Satellite Scatterometer Sea-Surface Wind Vectors (MetOp-A/B ASCAT) in the Korean Coastal Region (한반도 연안해역에서 인공위성 산란계(MetOp-A/B ASCAT) 해상풍 검증)

  • Kwak, Byeong-Dae;Park, Kyung-Ae;Woo, Hye-Jin;Kim, Hee-Young;Hong, Sung-Eun;Sohn, Eun-Ha
    • Journal of the Korean earth science society
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    • v.42 no.5
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    • pp.536-555
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    • 2021
  • Sea-surface wind is an important variable in ocean-atmosphere interactions, leading to the changes in ocean surface currents and circulation, mixed layers, and heat flux. With the development of satellite technology, sea-surface winds data retrieved from scatterometer observation data have been used for various purposes. In a complex marine environment such as the Korean Peninsula coast, scatterometer-observed sea-surface wind is an important factor for analyzing ocean and atmospheric phenomena. Therefore, the validation results of wind accuracy can be used for diverse applications. In this study, the sea-surface winds derived from ASCAT (Advanced SCATterometer) mounted on MetOp-A/B (METeorological Operational Satellite-A/B) were validated compared to in-situ wind measurements at 16 marine buoy stations around the Korean Peninsula from January to December 2020. The buoy winds measured at a height of 4-5 m from the sea surface were converted to 10-m neutral winds using the LKB (Liu-Katsaros-Businger) model. The matchup procedure produced 5,544 and 10,051 collocation points for MetOp-A and MetOp-B, respectively. The root mean square errors (RMSE) were 1.36 and 1.28 m s-1, and bias errors amounted to 0.44 and 0.65 m s-1 for MetOp-A and MetOp-B, respectively. The wind directions of both scatterometers exhibited negative biases of -8.03° and -6.97° and RMSE values of 32.46° and 36.06° for MetOp-A and MetOp-B, respectively. These errors were likely associated with the stratification and dynamics of the marine-atmospheric boundary layer. In the seas around the Korean Peninsula, the sea-surface winds of the ASCAT tended to be more overestimated than the in-situ wind speeds, particularly at weak wind speeds. In addition, the closer the distance from the coast, the more the amplification of error. The present results could contribute to the development of a prediction model as improved input data and the understanding of air-sea interaction and impact of typhoons in the coastal regions around the Korean Peninsula.

GOCI-II Capability of Improving the Accuracy of Ocean Color Products through Fusion with GK-2A/AMI (GK-2A/AMI와 융합을 통한 GOCI-II 해색 산출물 정확도 개선 가능성)

  • Lee, Kyeong-Sang;Ahn, Jae-Hyun;Park, Myung-Sook
    • Korean Journal of Remote Sensing
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    • v.37 no.5_2
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    • pp.1295-1305
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    • 2021
  • Satellite-derived ocean color products are required to effectively monitor clear open ocean and coastal water regions for various research fields. For this purpose, accurate correction of atmospheric effect is essential. Currently, the Geostationary Ocean Color Imager (GOCI)-II ground segment uses the reanalysis of meteorological fields such as European Centre for Medium-Range Weather Forecasts (ECMWF) or National Centers for Environmental Prediction (NCEP) to correct gas absorption by water vapor and ozone. In this process, uncertainties may occur due to the low spatiotemporal resolution of the meteorological data. In this study, we develop water vapor absorption correction model for the GK-2 combined GOCI-II atmospheric correction using Advanced Meteorological Imager (AMI) total precipitable water (TPW) information through radiative transfer model simulations. Also, we investigate the impact of the developed model on GOCI products. Overall, the errors with and without water vapor absorption correction in the top-of-atmosphere (TOA) reflectance at 620 nm and 680 nm are only 1.3% and 0.27%, indicating that there is no significant effect by the water vapor absorption model. However, the GK-2A combined water vapor absorption model has the large impacts at the 709 nm channel, as revealing error of 6 to 15% depending on the solar zenith angle and the TPW. We also found more significant impacts of the GK-2 combined water vapor absorption model on Rayleigh-corrected reflectance at all GOCI-II spectral bands. The errors generated from the TOA reflectance is greatly amplified, showing a large error of 1.46~4.98, 7.53~19.53, 0.25~0.64, 14.74~40.5, 8.2~18.56, 5.7~11.9% for from 620 nm to 865 nm, repectively, depending on the SZA. This study emphasizes the water vapor correction model can affect the accuracy and stability of ocean color products, and implies that the accuracy of GOCI-II ocean color products can be improved through fusion with GK-2A/AMI.

Kim Taek-yeong's Return to Korea in 1909 and Scholar Byeoksu in a Pavilion by An Jung-sik (김택영(金澤榮)의 1909년 귀국(歸國)과 안중식(安中植) 필(筆) <벽수거사정도(碧樹居士亭圖)>)

  • Kang, MinKyeong
    • MISULJARYO - National Museum of Korea Art Journal
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    • v.99
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    • pp.30-49
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    • 2021
  • Scholar Byeoksu in a Pavilion by An Jung-sik (1861-1919; sobriquet: Simjeon) was first shown to the public in the exhibition Art of the Korean Empire: The Emergence of Modern Art at the National Museum of Modern and Contemporary Art, Deoksugung. This painting bears poems and inscriptions composed by Kim Taek-yeong (1850-1927; sobriquet: Changgang) and written by Kwon Dong-su (1842-?; sobriquet: Seokun). A rare example of an actual-view landscape painting by An Jung-sik, this painting is significant in that it depicts upper-class houses in Seoul in the early twentieth century. More importantly, it demonstrates an association among intellectuals of the time. Yun Deok-yeong (1873-1940; sobriquet: Byeoksu), who asked An Jung-sik to create this painting, was an uncle of Empress Sunjeonghyo (1894-1966), the consort of Emperor Sunjong. He was one of the most prominent collaborators who promoted the Japanese colonization of Korea. When Emperor Sunjong bestowed Yun Deok-yeong with a hanging board with an inscription reading "Scholar Byeoksu in a Pavilion," Yun requested the production of this painting to mark the event. Kim Taek-yeong, a master of Chinese literature during the late Korean Empire period, sought asylum in Nantong, Jiangsu Province in China with his family a month before the Protectorate Treaty was signed between Korea and Japan in 1905. In 1909, he returned to Korea. His decision to return was greatly influenced by Yun Deok-yeong and Yi Jae-wan (1855-1922). Upon his return, Kim Taek-yeong intended to gather materials for publishing a history book. Also, Kim continuously met his old acquaintances, made new friends, and socialized with them. He built relationships with people from various backgrounds, including those living in regions like Gurye, and even in other countries like Japan. This indicates that intellectuals of the time were still forming networks through poems and prose regardless of their political inclination, social rank, or nationality. Scholar Byeoksu in a Pavilion is of great value in that it shows an aspect of the intellectual exchanges among the learned people of the late nineteenth and early twentieth centuries.

Distribution Prediction of Korean Clawed Salamander (Onychodactylus koreanus) according to the Climate Change (기후변화에 따른 한국꼬리치레도롱뇽(Onychodactylus koreanus)의 분포 예측에 대한 연구)

  • Lee, Su-Yeon;Choi, Seo-yun;Bae, Yang-Seop;Suh, Jae-Hwa;Jang, Hoan-Jin;Do, Min-Seock
    • Korean Journal of Environment and Ecology
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    • v.35 no.5
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    • pp.480-489
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    • 2021
  • Climate change poses great threats to wildlife populations by decreasing their number and destroying their habitats, jeopardizing biodiversity conservation. Asiatic salamander (Hynobiidae) species are particularly vulnerable to climate change due to their small home range and limited dispersal ability. Thus, this study used one salamander species, the Korean clawed salamander (Onychodactylus koreanus), as a model species and examined their habitat characteristics and current distribution in South Korea to predict its spatial distribution under climate change. As a result, we found that altitude was the most important environmental factor for their spatial distribution and that they showed a dense distribution in high-altitude forest regions such as Gangwon and Gyeongsanbuk provinces. The spatial distribution range and habitat characteristics predicted in the species distribution models were sufficiently in accordance with previous studies on the species. By modeling their distribution changes under two different climate change scenarios, we predicted that the distribution range of the Korean clawed salamander population would decrease by 62.96% under the RCP4.5 scenario and by 98.52% under the RCP8.5 scenario, indicating a sharp reduction due to climate change. The model's AUC value was the highest in the present (0.837), followed by RCP4.5 (0.832) and RCP8.5 (0.807). Our study provides a basic reference for implementing conservation plans for amphibians under climate change. Additional research using various analysis techniques reflecting habitat characteristics and minute habitat factors for the whole life cycle of Korean-tailed salamanders help identify major environmental factors that affect species reduction.

Estimation of Ground-level PM10 and PM2.5 Concentrations Using Boosting-based Machine Learning from Satellite and Numerical Weather Prediction Data (부스팅 기반 기계학습기법을 이용한 지상 미세먼지 농도 산출)

  • Park, Seohui;Kim, Miae;Im, Jungho
    • Korean Journal of Remote Sensing
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    • v.37 no.2
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    • pp.321-335
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    • 2021
  • Particulate matter (PM10 and PM2.5 with a diameter less than 10 and 2.5 ㎛, respectively) can be absorbed by the human body and adversely affect human health. Although most of the PM monitoring are based on ground-based observations, they are limited to point-based measurement sites, which leads to uncertainty in PM estimation for regions without observation sites. It is possible to overcome their spatial limitation by using satellite data. In this study, we developed machine learning-based retrieval algorithm for ground-level PM10 and PM2.5 concentrations using aerosol parameters from Geostationary Ocean Color Imager (GOCI) satellite and various meteorological parameters from a numerical weather prediction model during January to December of 2019. Gradient Boosted Regression Trees (GBRT) and Light Gradient Boosting Machine (LightGBM) were used to estimate PM concentrations. The model performances were examined for two types of feature sets-all input parameters (Feature set 1) and a subset of input parameters without meteorological and land-cover parameters (Feature set 2). Both models showed higher accuracy (about 10 % higher in R2) by using the Feature set 1 than the Feature set 2. The GBRT model using Feature set 1 was chosen as the final model for further analysis(PM10: R2 = 0.82, nRMSE = 34.9 %, PM2.5: R2 = 0.75, nRMSE = 35.6 %). The spatial distribution of the seasonal and annual-averaged PM concentrations was similar with in-situ observations, except for the northeastern part of China with bright surface reflectance. Their spatial distribution and seasonal changes were well matched with in-situ measurements.

A Study on the Protection and Management System of the Southwestern Coast Tidal Flat for Inscription in the World Heritage List (서남해안 갯벌의 세계유산 등재를 위한 보호 및 관리체계 연구)

  • Moon, Kyong-O
    • Korean Journal of Heritage: History & Science
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    • v.48 no.3
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    • pp.80-95
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    • 2015
  • The purpose of this study is to establish an effective protection and management system for World Heritage (WH) nomination of Southwestern Coast Tidal Flat (SCTF) by proposing a model of protection and management. SCTF has a potential to become a representative best practice to achieve a sustainable development for human society. SCTF has a potential Outstanding Universal Values (OUVs) for WH nomination, thus a harmony between human and nature for wise use of natural resources needs to be pursued. It is required to present the system of SCTF's protection and management and to analyze present status of the regions in the Tentative List by comparing the case which were already inscribed as WH. For better protection of nominated areas, SCTF should expand an area for protection with additional designation. For the management system, two separate management systems such as the Department of Culture & Tourism and the Department of Oceans & Fisheries need to be reconciled. Because of this overlapping management structure, the management of the nominated sites has been inefficient and long-term management plan is lacking. Therefore, it is necessary to integrate conflicting management system of each local government and make a long-term, integrated management plan. To make an efficient and sustainable protection and management, it is essential to set up a collaboration system by integrating various stakeholders such as central and local governments, academic organizations, local residents, and NGOs. As in the case of Wadden Sea, the combined community system of the stakeholders mentioned above should be established. Because it is essential for local residents to understand a basic concepts for protection and management, it is necessary to establish capacity-building of local people. The protection and management structure should be set up by bottom-up processes, that is the proper structure shoud be based on thorough research on local society as well as thorough communication with local residents to make relevant laws and policies. This study also propose the proper plan for better conservation and management of SCTF.