• The Journal of the Petrological Society of Korea
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• v.21 no.2
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• pp.151-171
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• 2012

The Permo-Triassic Songrim orogeny in the Korean peninsula was a major tectonic event involving complicated continental collisions at the eastern margin of Eurasia. Based on the previous studies on the metamorphic and deformations features of the Songrim orogeny, this paper presents metamorphic and structural characteristics and timing of the Songrim orogeny in the Taebaeksan basin, and discuss about correlation of the tectono-metamorphic evolution of the Taebaeksan basin with the Okcheon basin and the Imjingang belt with a combined analysis of bulk crustal shortening direction, metamorphic P-T and T-t (time) paths. The metapelites in the Pyeongan Supergroup in the northeastern margin of the Taebaeksan basin have experienced lower-temperature/medium-pressure (LT/MP) regional metamorphism followed by high-temperature contact metamorphism due to the Jurassic granite intrusion. The earlier LT/MP regional metamorphism produced two loops of clockwise P-T-d (deformation) paths combined with four deformation events ($D_1-D_4$). The first loop concomitant with $D_1$ and $D_2$ occurred at $400-500^{\circ}C$, 1.5-3.0 kbar, and related with growth of syn-$D_1$ chloritoid and andalusite, post-$D_1$ margarite, Ca-rich syn-$D_2$ or post-$D_2$ plagioclase. The second loop accompanying $D_3$ and $D_4$ occurred at $520-580^{\circ}C$, 2.0-6.0 kbar, and associated with the growth of syn-$D_3$ garnet and staurolite, and syn-$D_4$ and/or post-$D_4$ andalusite porphyroblasts. Furthermore the syn-$D_1$ chloritoid and andalusite porphyroblasts grew during E-W bulk crustal shortening, whereas the syn-$D_3$ garnet and staurolite, and the syn-$D_4$ and/or post-$D_4$ andalusite porphyroblasts have grown under N-S bulk crustal shortening. The similarity in the characteristics and timing of the metamorphism and bulk crustal shortening directions between the Okcheon and Imjingang belts suggest that the peak metamorphic conditions tend to increase toward the western part (Imjingang belt and southwestern part of the Gyeonggi Massif) from the eastern part (Taebaeksan basin). The E-W bulk crustal shortening influenced the eastern part of the Okcheon belt, whereas the N-S bulk crustal shortening resulted in strong deformation in the Imjingang and Okcheon belts. Consequently, the Permo-Triassic Songrim orogeny in the Korean peninsula is probably not only related to collision of the North and South China blocks, but also to the amalgamation of terrane fragments at the eastern Eurasia margin (e.g., collision of the Sino-Korean continent and the Hida-Oki terrane).

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.226-230
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• 2007

The purpose of this study was to analyze harmful heavy metals and residual pepsticides in 30 kinds of oriental medical materials. This study was carried out on 32 samples with 30 kinds of Oriental medical materials. The GC-ECD(Varian, CP-3800) was used to analyze residual pepsticides. ICP-OES(Varian, Vista-MPX) was used to analyze lead, arsenic, cadmium. Mercury was analyzed by amalgamation method. Arsenic was detected less than 3(mg/kg) in 21 samples and was not detected 11 samples. Lead was detected less than 5(mg/kg) in 25 samples and was not detected 7 samples. Mercury was detected less than 0.2(mg/kg) in 12 samples and was not detected 20 samples. Cadmium was detected more than 0.3(mg/kg) in 3 samples was detected less than 0.3(mg/kg) in 17 samples and was not detected 12 samples. A few residual pepsticides was detected, but all residual pepsticides was safe.

• Journal of the Korean Ceramic Society
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• v.39 no.3
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• pp.259-264
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• 2002

In this study, sintering properties of Artificial Lightweight aggregates(ALAs) prepared from coal ash as a function of sintering temperature (900$^{\circ}$C, 1000$^{\circ}$C, 1100$^{\circ}$C) and time (2min, 5min, 10min) when limestone added as lightweight mineral was investigated. Increasing the sintering temperature resulted simultaneously from a decline of quartz mineral as well as growth of mullite mineral. Addition of limestone to ALAs newly formed sintered minerals such as clinoptilolite and plagioclase. Sintering effect of ALAs prepared from coal ash and limestone was more affected by a sintering temperature than time. As sintering temperature and time increae, transition of macropore to micropore and formation of closed pores were happened, consequently shrank the total pore volume of ALAs. The surface of ALAs sintered at 1000$^{\circ}$C for 5min was nearly not detected open pores due toe amalgamation effect of molten slag layer but homogeneous distributions of closed pores with micro-scale were examined in cross sectional area ALAs. Sintering temperature and time which present the most adequate state, in the preparation of ALAs, are corresponded to 1000$^{\circ}$C and 5min, respectively.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.12a
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• pp.4-15
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• 2005

Methylmercury (MeHg) is an environmental pollutant with neurotoxic effects on the central nervous system. The major exposure route of MeHg to humans is via consumption of fish and shellfish which accumulate the chemical through the food web in an aquatic environment. Hair mercury level is an excellent marker for MeHg exposure. We have been conducting a survey on hair mercury contents among general populations from 14 districts to estimate the current Japanese MeHg exposure level. Total mercury levels of all hair samples collected (12923 in total) were analyzed by the oxygen combustion-gold amalgamation method using an atomic absorption mercury detector. Multiple regression analysis revealed that mercury levels were significantly correlated with several covariates, such as sex, age, the amount of daily intake of total fish/shellfish, a preference for certain fish such as tuna or bonito, and artificial waving. The geometric means for the population without artificial waving were 2.47 and 1.65 ${\mu}g/g$ for males (n = 5623) and females (n = 3470), respectively. Hair mercury levels varied with age, and the variations were more significant in males. Since the difference between sexes was not evident at younger ages, some hormonal control might also be involved in the mercury uptake by human hair. The average mercury levels in our hair samples varied among the sampling districts. Tuna is a major carnivorous fish with high mercury accumulations that is often consumed in Japan. The amount of fish consumption and the preference rate far tuna would appear to be responsible far the regional variation in hair mercury levels in Japan. Recently, a provisional tolerable weekly intake (PTWI) of MeHg was revised by 61st JECFA to 1.6 ${\mu}g/kg/week$, which was about half that of the Japanese standard, and corresponded to a hair level of 2.2 ppm. The distribution of hair mercury levels in Japanese populations in the present study indicated that 25% of the Japanese females of child-bearing age were estimated to be exposed to MeHg over the PTWI level. This would reflect the high Japanese consumption of marine products. However, not only mercury contamination, but also the nutritional benefit may have to be considered when discussing the risk involved in the current level of fish and shellfish consumption in Japan.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.4
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• pp.948-953
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• 2008

The purpose of this study was to analyze harmful heavy metals, sulfur dioxide and residual pesticides in 27 kinds of oriental medical materials. This study was carried out on 27 samples of oriental medical materials. The GC-ECD(Varian, CP-3800) was used to analyze residual pesticides. ICP-OES(Varian, Vista-MPX) was used to analyze lead, arsenic, cadmium. Mercury was analyzed by amalgamation method. A modified Monier-Williams method was used to analyze sulfur dioxide. Arsenic was detected less than 3(mg/kg) in 14 samples and was not detected 13 samples. Lead was detected less than 5(mg/kg) in 15 samples and was not detected 12 samples. Mercury was detected less than 0.2(mg/kg) in 15 samples and was not detected 12 samples. Cadmium was detected more than 0.3(mg/kg) in 3 samples was detected less than 0.3(mg/kg) in 16 samples and was not detected 11 samples. A few residual pesticides was detected, but all residual pesticides was safe. Sulfur dioxide was detected in all samples, but all residual sulfur dioxide was safe.

• Economic and Environmental Geology
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• v.45 no.4
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• pp.465-476
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• 2012

The Anatolia peninsula consists of several continental fragments that include the Pontide Block in north and the Anatolide-Touride Block in south as well as the Arabian Platform in southeast. These continental blocks were joined together into a single landmass in the late Tertiary. During most of the Phanerozoic these continental blocks were separated by paleo-oceans, such as Paleo-Tethys and Neo-Tethys. The Pontide Block in north show Laurasian affinities, and was only slightly affected by the Alpide orogeny; they preserve evidence for the Variscan and Cimmeride orogenies. The Pontic Block is composed of the Strandja, Istanbul and Sakarya zones that were amalgamated into a single terrane by the mid Cretaceous times. The Anatolide-Tauride Block in south shows Gondwana affinities but was separated from Gondwana in the Triassic and formed an extensive carbonate platform during the Mesozoic. The Anatolide-Tauride Block was intensely deformed and partly metamorphosed during the Alpide orogeny; this leads to the subdivision of the Anatolide-Tauride Block into several zones on the basis of the type and age of metamorphism and deformation. The Arabian Platform in southeast forms the northernmost extension of the Arabian Plate that shows a stratigraphy similar to the Anatolide-Tauride Block with a clastic-carbonate dominated Palaeozoic and a carbonate dominated Mesozoic succession. A new tectonic era started in Anatolia Peninsula in the Oligocene-Miocene after the final amalgamation of these continental blocks and plate. This neotectonic phase is characterized by extension, and strike-slip faulting, continental sedimentation, and widespread calcalkaline magmatism, which played a very important role in producing beautiful landscapes of the Anatolia Peninsula today.

• Korean Journal of Food Science and Technology
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• v.14 no.2
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• pp.168-173
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• 1982

The present study was carried to observe the total mercury contents in fresh-water fishes which were collected from 24 streams in the South-East area, Korea. These total mercury contents were determined by quartz tube combustion gold amalgamation method. The value of total mercury contents in collected fresh-water fishes ranged from 0.02ppm to 0.12ppm and the mean value were 0.07ppm. The total value of mercury contents differed with the fish species showing 0.09ppm in Carassius auratus, 0.10ppm in Coilia ectenes, 0.11ppm in Moroca lagowskii and Squalidus majime and 0.12ppm in Cobitis taenia which were highly more than the mean value of collected fishes. The mean value of the total mercury contents in the Yeong Il Gun (0.09PPm), Gim Hae Gun (0.08ppm) and Meong Ju Gun (0.08ppm) were highly detected than those of other surveyed areas.

• Journal of Conservation Science
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• v.27 no.1
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• pp.1-11
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• 2011

For the silver artifacts in the Koryo Dynasty excavated from Neungnae-ri Ganghwa island, the metallographic section analysis and hardness and chemical analysis were conducted. After making samples in the similar ratio of the composition concentration, the changes of the microstructure were checked according to the working method and temperature. The results show that those silver artifacts are Au-Cu alloys with 2 to 6 % of Cu. From the results it is judged that Cu was artificially alloyed with them to keep the proper hardness and identified that they were gilded by the amalgamation process seeing that mercury was included at the guilt layer. Also the porous texture on the surface of them could be formed at over $400^{\circ}C$, therefore, it is assumed the hot working or heat treatment at over $400^{\circ}C$ were performed. In silver artifacts made by the relief and repousse, they have the similar composition analysis to other 7 artifacts but the hardness is lower than pure silver. Consequently from differences in the hardness, it can be inferred that the low hardness of silver artifacts is concerned with manufacturing techniques.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.12-20
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• 2016

With the enhancements in existing major industries, cloud computing-based converging services have been created, as well as value-added industries. A variety of converging services are now provided, from personalized services up to industrial services. In Korea, they have become the driving force behind existing industries throughout the whole economy, but mainly in finance, mobile systems, social computing, and home services, based on cloud services. However, not only denial of service (DOS) and distributed DOS (DDOS) attacks have occurred, but also attack techniques targeting core data in storage servers. Even security threats that are hardly detected, such as multiple attacks on a certain target, APT, and backdoor penetration have also occurred. To supplement defenses against these, in this article, a protocol for authority management is designed to provide users with safe storage services. This protocol was studied in cases of integration between a cloud environment and big data-based technology, security threats, and their requirements. Also studied were amalgamation examples and their requirements in technology-based cloud environments and big data. With the protocol suggested, based on this, security was analyzed for attack techniques that occur in the existing cloud environment, as well as big data-based techniques, in order to find improvements in session key development of approximately 55%.

• The Journal of Korean Philosophical History
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• no.50
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• pp.113-138
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• 2016

The purpose of this research is to establish the foundation for understanding the appearance of development, inheritance and acceptance of Toegye Yi Hwang(退溪李滉, 1501~1570)'s theory after his life by examining Udam Jeong Sihan(愚潭 丁時翰, 1625~1707)'s view on the Ido-seol(理到說), the Toegye's latter theory. After Toegye, Ido-seol was translated as 'The principle of matters reaches the human mind'. Galam Yi Hyunil(葛庵 李玄逸, 1627~1704), the contemporary scholar with Udam, criticized this translation for applying the directivity and motility to 'Li', the immovable principle. However, Udam agreed with the conventional interpretation of Ido-seol and understood it as the consilience of mind which got the entire principle(體) of 'Li(理)' and contained the application(用) of all things. He extended this concept as the level of 'sameness between objects and self [物我爲一]' based on his former theory, the exquisite interpretation of 'application of Li'. The meaning of 'sameness between objects and self[物我爲一]' is not amalgamation but applepie order of matter's principle in mind. The Udam's viewpoint is differ from Galam who tried to overcome the structural limit of Ido-seol by transforming 'Do(到)', the predicate of 'Ido(理到)', into 'Jin(盡)'. It means that he tried to interpret 'Ido(理到)' on the more essential aspect. His view can be the useful tool for understanding the Toegye's neo-Confucianism system with 'Li(理)' as central figure. It suggested that Udam's theory of the principle and the applecation of 'Li' can be the important theory to investigate the formation of Toegye schools' though and its development.