• Title/Summary/Keyword: Process of Change

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Transformation of Asbestos-Containing Slate Using Exothermic Reaction Catalysts and Heat Treatment (발열반응 촉매제와 열처리를 이용한 석면함유 슬레이트의 무해화 연구)

  • Yoon, Sungjun;Jeong, Hyeonyi;Park, Byungno;Kim, Yongun;Kim, Hyesu;Park, Jaebong;Roh, Yul
    • Economic and Environmental Geology
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    • v.52 no.6
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    • pp.627-635
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    • 2019
  • Cement-asbestos slate is the main asbestos containing material. It is a product made by combining 10~20% of asbestos and cement components. Man- and weathering-induced degradation of the cement-asbestos slates makes them a source of dispersion of asbestos fibres and represents a priority cause of concern. When the asbestos enters the human body, it causes cellular damage or deformation, and is not discharged well in vitro, and has been proven to cause diseases such as lung cancer, asbestos, malignant mesothelioma and pleural thickening. The International Agency for Research on Cancer (IARC) has designated asbestos as a group 1 carcinogen. Currently, most of these slats are disposed in a designated landfill, but the landfill capacity is approaching its limit, and there is a potential risk of exposure to the external environment even if it is land-filled. Therefore, this study aimed to exam the possibility of detoxification of asbestos-containing slate by using exothermic reaction and heat treatment. Cement-asbestos slate from the asbestos removal site was used for this experiment. Exothermic catalysts such as calcium chloride(CaCl2), magnesium chloride(MgCl2), sodium hydroxide(NaOH), sodium silicate(Na2SiO3), kaolin[Al2Si2O5(OH)4)], and talc[Mg3Si4O10(OH)2] were used. Six catalysts were applied to the cement-asbestos slate, respectively and then analyzed using TG-DTA. Based on the TG-DTA results, the heat treatment temperature for cement-asbestos slate transformation was determined at 750℃. XRD, SEM-EDS and TEM-EDS analyses were performed on the samples after the six catalysts applied to the slate and heat-treated at 750℃ for 2 hours. It was confirmed that chrysotile[Mg3Si2O5(OH5)] in the cement-asbestos slate was transformed into forsterite (Mg2SiO4) by catalysts and heat treatment. In addition, the change in the shape of minerals was observed by applying a physical force to the slate and the heat treated slate after coating catalysts. As a result, the chrysotile in the cement-asbestos slate maintained fibrous form, but the cement-asbestos slate after heat treatment of applying catalyst was broken into non-fibrous form. Therefore, this study shows the possibility to safely verify the complete transformation of asbestos minerals in this catalyst- and temperature-induced process.

Risk Management and Strategies in Airport Security Check (공항 보안검색에 있어서의 위험관리와 대응과제)

  • Kim, Jae-Woon
    • Korean Security Journal
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    • no.34
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    • pp.89-113
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    • 2013
  • Travel by airplane using airport in globalized modern society is familiar to our life but such airport can be a target of terrorists who would threaten our safety. However, aviation terrorism which is represented by 9.11 terror gives horror beyond our imagination to modern people. Since the first airplane hijacking in Peru in 1931 happened, security organization in each nation has taken various prevention measures to block aviation terrorism. The most realistic measures to prevent aviation terrorism would be security check activity to control approach of terrorist that passengers on airplane and cargos are checked to find out dangerous article like explosive etc. But security check activity in Korea shifted to security check activity focused on private security for efficiency of airport operation differently from security check activity in advanced countries where public interests is strengthened according to risk of terror after 9.11 system. That is, since Incheon airport opened in March 2001, security check system focused on the police was changed. Now Incheon international airport Corporation instructs and supervises security check job and private security personnel are in charge of actual security check activity. But this check system has limitation in blocking terror activity by terrorists which is systematized and intelligent as time passes due to deteriorated job satisfaction of private security personnel and confusing supervising system. Accordingly, it is suggested to introduce risk management skill which is one of management strategy of private corporation for security check activity to prevent terror activity. With this skill, risk factors of aviation terror are identified and analyzed regularly, and each process such as setting of priority, activity to reduce risk, and assessment of security is carried out. And it would be necessary to do efforts, for example, to properly change level of security check according to threat of terror such as to place policeman at airport security in case threat of terror is severe. On the other hand, it is necessary to establish national police organization for good communication of security check activity in field and supervising function, which can encourage systematization and specialization of aviation security job.

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An Quantitative Analysis of Severity Classification and Burn Severity for the Large Forest Fire Areas using Normalized Burn Ratio of Landsat Imagery (Landsat 영상으로부터 정규탄화지수 추출과 산불피해지역 및 피해강도의 정량적 분석)

  • Won, Myoung-Soo;Koo, Kyo-Sang;Lee, Myung-Bo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.3
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    • pp.80-92
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    • 2007
  • Forest fire is the dominant large-scale disturbance mechanism in the Korean temperate forest, and it strongly influences forest structure and function. Moreover burn severity incorporates both short- and long-term post-fire effects on the local and regional environment. Burn severity is defined by the degree to which an ecosystem has changed owing to the fire. Vegetation rehabilitation may specifically vary according to burn severity after fire. To understand burn severity and process of vegetation rehabilitation at the damaged area after large-fire is required a lot of man powers and budgets. However the analysis of burn severity in the forest area using satellite imagery can acquire rapidly information and more objective results remotely in the large-fire area. Space and airbone sensors have been used to map area burned, assess characteristics of active fires, and characterize post-fire ecological effects. For classifying fire damaged area and analyzing burn severity of Samcheok fire area occurred in 2000, Cheongyang fire in 2002, and Yangyang fire in 2005 we utilized Normalized Burn Ratio(NBR) technique. The NBR is temporally differenced between pre- and post-fire datasets to determine the extent and degree of change detected from burning. In this paper we use pre- and post-fire imagery from the Landsat TM and ETM+ imagery to compute the NBR and evaluate large-scale patterns of burn severity at 30m spatial resolution. 65% in the Samcheok fire area, 91% in the Cheongyang fire area and 65% in the Yangyang fire area were corresponded to burn severity class above 'High'. Therefore the use of a remotely sensed Differenced Normalized Burn Ratio(${\Delta}NBR$) by RS and GIS allows for the burn severity to be quantified spatially by mapping damaged domain and burn severity across large-fire area.

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Differential Diagnosis of Metastatic Bone Disease and Benign Bone Disease on Spine SPECT in Patients with Low Back Pain (요통 환자의 척추골 SPECT에서 골전이 병변과 양성골질환의 섭취 양상 분석을 통한 감별진단이 가능한가)

  • Lee, Seung-Hun;Choi, Yun-Young;Cho, Suk-Shin
    • The Korean Journal of Nuclear Medicine
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    • v.35 no.6
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    • pp.371-377
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    • 2001
  • Purpose: One or more abnormal vertebrae detected on bone scintigraphy is a common finding in clinical practice, and it could pose a diagnostic dilemma especially in cancer patients. as either metastasis or benign disease may cause scintigraphic abnormality. The purpose of this study was to determine whether additional spine SPECT has a role in differentiating malignant from benign lesions in patients with back pain. Materials and Methods: We reviewed spine SPECT studios obtained over a three-year period in 108 patients. Among them, forty-five patients with abnormal SPECT and clinically followed records were evaluated (20 cancer patients were included). Uptake patterns were classified as follows: 1. Body: diffusely increased uptake, linear increased uptake of end plate, segmental increased uptake, and cold defect, 2. Posterior element: posterior to body (pedicle), posterior to Intervertebral disc space (facet joint), and spinous process. Lesions were correlated with radiological findings and with final diagnosis. Results: Sixty-nine bone lesions were detected on SFECT images, including 18 metastases, 28 degenerative diseases and 21 compression fractures. Cold defect (6) and segmental increased uptake (5) were dominant findings in metastasis; linear increased uptake (12), and facet joint uptake (15) were in degenerative change; and diffuse increased uptake (9), and linear increased uptake (9) were in compression fracture. Conclusion: Cold defect and segmental increased uptake of body were characteristic findings of metastasis, but care should be taken because compression fracture also shows segmental increased uptake in some cases. Degenerative disease was easily diagnosed because of the typical finding of linear increased uptake of end plate and facet joint. Therefore, additional bone SPECT after planar bone scan would be helpful for differentiating metastasis from benign condition in cancer patients.

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Foreign Investors Response to the Foreign Exchange Rate Risk in the Korean Stock Markets (한국 주식시장에서 환위험에 대한 외국인 투자자의 반응)

  • Park, Jong-Won;Kwon, Taek-Ho;Lee, Woo-Baik
    • The Korean Journal of Financial Management
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    • v.25 no.4
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    • pp.53-78
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    • 2008
  • Foreign investors who invest in the Korean stock markets are exposed to two kinds of foreign exchange rate risk, the economic exposure and the translation exposure. The former is the foreign exchange rate exposure in return generating process of the assets invested and the latter is the foreign exchange rate exposure in the translation of domestic return into foreign investors' currency. Domestic investors, however, are exposed only to foreign exchange rate exposure in the asset invested. This different situation on foreign exchange rate exposure between foreign investors and domestic investors can induce different response to exchange rate change by investor groups. Previous studies on foreign exchange rate exposure of Korean firms reported that quite a few Korean firms are exposed to foreign exchange risks and suggested to manage the foreign exchange risks. Also, many studies on the market segmentation showed that a market can be practically segmented according to the characteristics of investor groups. These studies support the hypothesis that the Korean stock market can be practically segmented by the foreign investors' attitude to the foreign exchange rate exposure. This study examines the response of both foreign investors and domestic investors to the foreign exchange rate exposures in Korean stock markets. Test results show that foreign investors increase their sell transactions when the foreign exchange rate exposure of the previous day is negative. This result can be possible when foreign investors attempt to actively manage the decrease in value of their assets due to rising of exchange rate. Analysis on the sell order data is also supportive to this interpretation. Foreign investors also increase their buy transactions when the foreign exchange rate exposure of the previous day is negative. This result can be possible when foreign investors use actively the relation between the increase in asset value and the translation gain due to declining of exchange rate. Analyses on buy order data, however, do not show the same result as the analyses on transaction data. This difference may come from the difference of information contained in transaction data and order data. In summary, the result of the paper supports the hypothesis that foreign investors response differently to foreign exchange rate exposure compared with domestic, Korean investors. Two groups do not show different response when exchange rate exposure is positive, i.e., as foreign exchange rate is increase (decrease), the asset value is increase (decrease). However, foreign investors' response is different from that of domestic investors when exchange rate exposure is negative, i.e., as foreign exchange rate is increase (decrease), the asset value is decrease (increase). These results mean that foreign investors and domestic investors are placed in different situations related to foreign exchange rate exposure, and these differences are reflected in the Korean stock markets. And domestic investors need to consider foreign investors' different attitude to the foreign exchange rate exposure when they analysis foreign investors' trading behavior.

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A Study of Sound Expression in Webtoon (웹툰의 사운드 표현에 관한 연구)

  • Mok, Hae Jung
    • Cartoon and Animation Studies
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    • s.36
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    • pp.469-491
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    • 2014
  • Webtoon has developed the method that makes it possible to express sound visually. Also we can also hear sound in webtoon through the development of web technology. It is natural that we analyze the sound that we can hear, but we can also analyze the sound that we can not hear. This study is based on 'dual code' in cognitive psychology. Cartoonists can make visual expression on the basis of auditive impression and memory, and readers can recall the sound through the process of memory and memory-retrieval. This study analyzes both audible sound and inaudable sound. Concise analysis owes the method to film sound theory. Three main factor, Volume, pitch, and tone are recognized by frequency in acoustics. On the other hand they are expressed by the thickness and site of line and image of sound source. The visual expression of in screen sound and off screen sound is related to the frame of comics. Generally the outside of frame means off sound, but some off sound is in the frame. In addition, horror comics use much sound for the effect of genre like horror film. When analyzing comics sound using this kinds of the method film sound analysis, we can find that webtoon has developed creative expression method comparing with simple ones of early comics. Especially arranging frames and expressing sound following and vertical moving are new ones in webtoon. Also types and arrangement of frame has been varied. BGM is the first in using audible sound and recently BGM composed mixing sound effect is being used. In addition, the program which makes it possible for readers to hear sound according to scroll moving. Especially horror genre raise the genre effects using this technology. Various methods of visualizing sound are being created, and the change shows that webtoon could be the model of convergence in contents.

National brand development research strategy using traditional Korean patterns (한국 전통 문양을 활용한 국가 브랜드 연구 개발 전략 - 금문(錦紋)을 중심으로 -)

  • KIM, Mihye
    • Korean Journal of Heritage: History & Science
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    • v.54 no.4
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    • pp.232-245
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    • 2021
  • The present study is about a brand development strategy that utilizes Korean traditional patterns. The global culturenomics phenomenon confirms the value of the cultural aspects of design when a national brand is established. People succeed with their unique aesthetic sense and reinterpret it in a modern view, and this design acts as today's national brands. In this way, people used traditional patterns and original designs, along with regional characteristics and formative style, in developing their designs. However, due to recent changes in the global environment, modern people live in an "untact" world, and consumption culture shifted toward online marketing. In this environment, where one is isolated from social activities, there needs to be a strong image that can dramatically change the mood of one's home. I would like to re-examine the Dan-Chung pattern, whose painting depends on the aesthetic characteristics of architecture to protect the wooden members of the framework in traditional architecture. The pattern and color of Dan-Chung, coated in traditional architecture, differs by the type of construction used, which includes a palace, a Buddhist temple, and a Confucianism Dan Chung. The Geummoon pattern contains aesthetic factors to add solemnity to the Main Buddhist Halls, which contain Buddha. This is a new medium that continues the current traditions instead of remaining in the past. Among different Dan Chung patterns, Geummoon has magnificent decoration consisting of the highest grade materials and unique composition; therefore, it is suitable to be reinterpreted in modern terms. The same pattern can be interpreted in different ways with different colors, so there is a great aesthetic impression in the Geummoon pattern. The value of preservation for exploration and theoretical study of the traditional pattern is important, but recreating the pattern into modern formative art can present a new angle of view and national brand, bearing pride in our cultural assets. The study used multidimensional molding methods for realistic presentation after going through the two-dimensional design process. The significant value of Korean molding beauty which hangs onto the past will play a crucial role in establishing our national brand.

Voltammetric Sensor Incorporated with Conductive Polymer, Tyrosinase, and Ionic Liquid Electrolyte for Bisphenol F (전도성고분자, 티로시나아제 효소 및 이온성 액체 전해질을 융합한 전압전류법 기반의 비스페놀F 검출 센서)

  • Sung Eun Ji;Sang Hyuk Lee;Hye Jin Lee
    • Applied Chemistry for Engineering
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    • v.34 no.3
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    • pp.258-263
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    • 2023
  • In this study, conductive polymers and the enzyme tyrosinase (Tyr) were deposited on the surface of a screen printed carbon electrode (SPCE), which can be fabricated as a disposable sensor chip, and applied to the detection of bisphenol F (BPF), an endocrine disruptor with proven links to male diseases and thyroid disorders, using electrochemical methods. On the surface of the SPCE working electrode, which was negatively charged by oxygen plasma treatment, a positively charged conductive polymer, poly(diallyldimethyl ammonium chloride) (PDDA), a negatively charged polymer compound, poly(sodium 4-styrenesulfonate) (PSS), and another layer of PDDA were layered by electrostatic attraction in the order of PDDA, PSS, and finally PDDA. Then, a layer of Tyr, which was negatively charged due to pH adjustment to 7.0, was added to create a PDDA-PSS-PDDA-Tyr sensor for BPF. When the electrode sensor is exposed to a BPF solution, which is the substrate and target analyte, 4,4'-methylenebis(cyclohexa-3,5-diene-1,2-dione) is generated by an oxidation reaction with the Tyr enzyme on the electrode surface. The reduction process of the product at 0.1 V (vs. Ag/AgCl) generating 4,4'-methylenebis(benzene-1,2-diol) was measured using cyclic and differential pulse voltammetries, resulting in a change in the peak current with respect to the concentration of BPF. In addition, we compared the detection performance of BPF using an ionic liquid electrolyte as an alternative to phosphate-buffered saline, which has been used in many previous sensing studies. Furthermore, the selectivity of bisphenol S, which acts as an interfering substance with a similar structure to BPF, was investigated. Finally, we demonstrated the practical applicability of the sensor by applying it to analyze the concentration of BPF in real samples prepared in the laboratory.

A Study on Interactive Animation Production as Public Art : Focusing on an Case of the Live Window Animation, (공공예술로서의 인터랙티브 애니메이션 제작 연구 : 라이브 윈도우 애니메이션 <북극곰 파오> 사례를 중심으로)

  • Chang, Wook-Sang;Yu, Seung-Cheol
    • Cartoon and Animation Studies
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    • s.33
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    • pp.153-172
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    • 2013
  • There are many cases that messages of boring contents of most contents with public interests appear on the surface. Audiences don't think these contents are interesting. It is true that animations cannot be generally boring when delivering messages of public interests. was produced to focus on making audiences experience that a global warming story, the boring and textbook contents is interesting. And it was composed by the multiform story to realize narration through audiences' participation by utilizing the characteristics of live windows, not just watching the animation. This paper examines the differences between theaters and live window through the case that was produced and examples which utilized interaction for audiences' participation based on this. It analyzes the differences between environments according to characteristics of places and audiences in the differences between the theaters and live window, examines the examples to utilize interaction focusing on the process that narration is gradually changed as response to user environment design and interaction for unspecified individuals, and suggests direction that animation should move forward as public art based on the results to show the animation in Millano Piazza. According to the characteristics of live windows, the audiences of are people in the streets who are heading for different destinations, not the ones who come to theaters to watch the animation. Showing the animation with narration to them was a new attempt. When it began to show it in Millano Piazza, the audiences were very satisfied with the experiences that the stories were changed as they participated in it by themselves and naturally thought of global warming problems. You cannot know how the message of change people's habits and thoughts for the present, but this attempt was an opportunity that animations play the social role. Many animations are being produced in the world. Most of them are being done to aim at theaters, TVs, and film festivals. They should meet audiences through more various methods. One of them is animations as public art. And can be the new attempt in this sense. And in the future, animations as public art should make efforts to show you interesting experiences that you can share thoughts to be able to live together. As art of various media is changing to the one which considers public interests, animations can be new types of public art by integrating them with various technologies.

IN VITRO STUDY ON THE EFFECTS OF THE FLOURIDE ON THE REMINERALIZATION OF ACID ETCHED ENAMEL (불소가 산부식된 법랑질의 재석회화에 미치는 영향에 관한 연구)

  • Kim, Jin-Han;Lee, Ki-Soo
    • The korean journal of orthodontics
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    • v.26 no.4
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    • pp.389-399
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    • 1996
  • Remineralization of acid-etched enamel across the time has been one of the curiosities in the context of the orthodontic biomechanics(Arends J. et al., IRL Press, 1, 1985), nevertheless, is so far controversial. It was the aim of this study to observe the remineralization patterns of acid-etched enamel across the time and whether the existence of fluoride might carry out any modifications. The intact buccal surfaces of the first bicuspids which was extracted for orthodontic treatment were ground smooth, and etched with a 38w/w% phosphoric acid for 60 seconds, The surface was observed by the scanning electron microscope and surface microhardness was measured after immersion in the fluoride or non-fluoride containing remineralizing solution for 0 hour, 12 hours, 1 day, 3 days, 7 days, 14 days, 28 days, and 42 days. The following results and conclusions were drawn; 1. Surface microhardness increased in both fluoride containing and non-fluoride containing solution group with time lapse. 2. In fluoride containing solution group, the surface microhardness sharply increased at the 12 hours group, on the other hand, surface microhardness increased at 3 days in non-fluoride containing solution group. 3. The difference in microhardness value between two groups manifested gradual decrease. 4. Scanning electron microphotographs disclosed that the fluoride containing solution group generated spiculate sub-stances in the 12 hours group, which was increased in number and size with time lapse. 7 days later, spherical composure was began to be produced, The spiculate substances so much increased in number that the etched enamel surface looked like flat in 42 days. 5. In non fluoride-containing solution group, there was no surface change at 42 days, perceivable in scanning electron microphotographs which could be defined as remineralization though the surface was a little rougher than the incipient etched surface. These results demonstrate that the action of the fluoride is exceedingly pertinent in the remineralization of acid-etched enamel and the remineralization process goes uninterruptedly with time lapse.

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