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NATURAL ATTENUATION OF HAZARDOUS INORGANIC COMPONENTS: GEOCHEMISTRY PROSPECTIVE (유해 무기질의 자연정화 : 지화학적 고찰)

  • Lee, Suk-Young;Lee, Chae-Young;Yun, Jun-Ki
    • Proceedings of the KSEEG Conference
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    • 2002.06a
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    • pp.81-100
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    • 2002
  • While most of regulatory communities in abroad recognize ' 'natural attenuation " to include degradation, dispersion, dilution, sorption (including precipitation and transformation), and volatilization as governing Processes, regulators prefer "degradation" because this mechanism destroys the contaminant of concern. Unfortunately, true degradation only applies to organic contaminants and short- lived radionuclides, and leaves most metals and long-lived radionuclides. The natural attenuation Processes may reduce the potential risk Posed by site contaminants in three ways: (i)contaminants could be converted to a less toxic form througy destructive processes such as biodegradation or abiotic transformations; (ii) potential exposure levels may be reduced by lowering concentrations (dilution and dispersion); and (iii) contaminant mobility and bioavailability may be reduced by sorption to geomedia. In this review, authors will focus will focul on "sorption" among the natural attenuation processes of hazardous inorganic contaminants including radionuclides. Note though that sorption and transformation processes of inorganic contaminants in the natural setting could be influenced by biotic activities but our discussion would limit only to geochemical reactions involved in the natural attenuation. All of the geochemical reactions have been studied in-depth by numerous researchers for many years to understand "retardation" process of contaminants in the geomedia. The most common approach for estimating retardation is the determination of distrubution coefficiendts ($K_{d}$) of contaminants using parametric or mechanistic models. As typocally used in fate and contaminant transport calculations such as predictive models of the natural attenuation, the $K_{d}$ is defined as the ratio of the contaminant concentration in the surrounding aqueous solution when the system is at equilibrium. Unfortunately, generic or default $K_{d}$ values can result in significant error when used to predict contaminant migration rate and to select a site remediation alternative. Thus, to input the best $K_{d}$ value in the contaminant transport model, it is essential that important geochemical processes affecting the transport should be identified and understood. Precipitation/dissolution and adsorption/desorption are considered the most important geochemical processes affecting the interaction of inorganic and radionuclide contaminants with geomedia at the near and far field, respectively. Most of contaminants to be discussed in this presentation are relatively immobile, i.e., have very high $K_{d}$ values under natural geochemical environments. Unfortunately, the obvious containment in a source area may not be good enough to qualify as monitored natural attenuation site unless owner demonstrate the efficacy if institutional controls that were put in place to protect potential receptors. In this view, natural attenuation as a remedial alternative for some of sites contaminated by hazardous-inorganic components is regulatory and public acceptance issues rather than scientific issue.

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Study on an Image Reconstruction Algorithm for 3D Cartilage OCT Images (A Preliminary Study) (3차원 연골 광간섭 단층촬영 이미지들에 대한 영상 재구성 알고리듬 연구)

  • Ho, Dong-Su;Kim, Ee-Hwa;Kim, Yong-Min;Kim, Beop-Min
    • Progress in Medical Physics
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    • v.20 no.2
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    • pp.62-71
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    • 2009
  • Recently, optical coherence tomography (OCT) has demonstrated considerable promise for the noninvasive assessment of biological tissues. However, OCT images difficult to analyze due to speckle noise. In this paper, we tested various image processing techniques for speckle removal of human and rabbit cartilage OCT images. Also, we distinguished the images which get with methods of image segmentation for OCT images, and found the most suitable method for segmenting an image. And, we selected image segmentation suitable for OCT before image reconstruction. OCT was a weak point to system design and image processing. It was a limit owing to measure small a distance and depth size. So, good edge matching algorithms are important for image reconstruction. This paper presents such an algorithm, the chamfer matching algorithm. It is made of background for 3D image reconstruction. The purpose of this paper is to describe good image processing techniques for speckle removal, image segmentation, and the 3D reconstruction of cartilage OCT images.

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A Study on the Visual Effects of Non-Photorealistic Rendering Animation focusing on 'Paperman,' a Short Animation (넌-포토리얼리스틱(Non-Photorealistic) 렌더링 애니메이션의 시각 효과 기법 - 단편 애니메이션 Paperman을 중심으로)

  • Park, Sung-Won
    • Cartoon and Animation Studies
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    • s.40
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    • pp.139-155
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    • 2015
  • Animation is completed in accordance with the original planning of visual direction in the process of post-production. Especially, a variety of visualization skills to meet the planning idea are directed in editing and compositing processes such as rendering and shading in the production of 3D animation. Therefore, the studies how to implement these visual effects have been conducted since the emergence of the animation. The rendering method which appears in the recent animations so often is the effect of 2D animation style although it is applied by 3D technique. 3D animation can be classified as two types including photo realistic and non-photo realistic renderings. The former is to render the images realistically while the latter is to highlight the formative effect with analogue style free from the realism of the photographs. Visual effect of 2D animation is non-realistic, that is, non-photo realistic rendering. The animations produced by this method have the depth of 3D animation expression in terms of space and animating, and can direct the viewer-friendly analogue style visuals, which are widely used as a post-production effect. Hence in this study, we selected a short animation, 'Paperman,' one of Disney's animations, produced by cartoon rendering method which belongs to the class of non-photo rendering technique in 3D graphics, as our subject. We analyzed their techniques and visual effects of the scenes expressed by cartoon rendering method so as to understand whether they meet the original direction idea with the composition work. In addition, we expect further developments of post-production methods, exceeding the limit of graphic expression in alignment with the trend that has become more various in the types and genres of non-photo rendering.

Actual Vegetation of Dodamsambong (Scenic Site no. 44) and Danyangseokmoon (Scenic Site no. 45) in Danyang-gun (단양군 도담삼봉과 단양석문 일대의 현존식생)

  • Choi, Byoung-Ki
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.32 no.2
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    • pp.116-123
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    • 2014
  • The description of vegetation cover and floral composition was undertaken in terms of phytosociological study in Dodamsambong(scenic site no. 44) and Danyangseokmoon(no. 45). In this study a total of 17 $relev{\acute{e}}s$ containing 144 taxa were collected and analyzed. Eight plant communities are differentiated, grouped into 4 physiognomic types: forest type(Buxus microphylla var. koreana-Thuja orientalis community, Tilia mandshurica-Quercus variabilis community, and Cynanchum wilfordii-Pinus densiflora community), mantle type(Cardamine leucantha-Neillia uekii community), secondary meadow type(Galium kinuta-Spodiopogon sibiricus community, Diarthron linifolium-Zoysia japonica community), and crevice type(Patrinia rupestris-Selaginella stauntoniana community, Hypodematium glandulosopilosum community). The vegetation of Dodamsambong and Danyangseokmoon is characterized by local flora, such as calciphilous plants, geological distribution-limit species, and endemic species. The soil depth, slope, and human impact have been identified as the most important differentiating ecological factors. Buxus microphylla var. koreana-Thuja orientalis community, Tilia mandshurica-Quercus variabilis community, and Patrinia rupestris-Selaginella stauntoniana community were evaluated highly by National Vegetation Naturalness. In order to restore the value of specific landscape for scenic site, we should improve the problems of protected area such as wrong management on habitat, forest fragmentation by facilities and decline in vegetation by lack of growing the next succession.

Commercialization Success Factors of Transfer Technology from Public R & D and Enhancing Performance (공공R&D 이전기술의 사업화 성공요인 분석 및 성과제고 방안)

  • Park, Ji-One;Youn, Su-Jin;Park, Beom-Soo
    • Journal of Korea Technology Innovation Society
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    • v.18 no.1
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    • pp.28-48
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    • 2015
  • This study is public R & D institutions report to verify what the impact factors on the course of progress of industrialization based on technology companies who previously received prior to the developed technology, what policies and plans for the next requirements based on this by offering the implications for business rate was to contribute to the improvement of the public research institution technology transfer. In this study, the influence factors on technology commercialization derived through the analysis of existing and previous studies, the characteristics of the previously received corporate environmental characteristics and previous technologies through a survey of the company received a technology transfer from public research institutions commercialization decisions and contributions, including sales and commercialization of the results were analyzed by logistic regression analysis demonstrated how to have relevance. Analysis, and linkage with high production company has an existing case of IT technology transfer, commercialization of higher technical success rate was higher compatibility. On the other hand, were observed and expected success rate were higher when a rather commercialized technologies independently be earlier than if participating in joint research in the development of the technology, unlike previously, completeness of the prior art did not significantly affect. This study has the following policy implications. Public research institutions have developed technologies are commercialized to figure out what the requirements of the technical aspects of consumer technologies in order to create economic wealth. And for technology commercialization for enough technical competencies to absorb the technology, and that the technology and considering the link between business and technology commercialization success to be applied. This study has some limitations. First, the sample size was not sufficient. In relation to the presence and participation of corporate success and commercialization of the R & D process, with many previous studies are needed more in-depth analysis by leading research in the sense that different results are obtained. Also did not reflect the will or the corporate culture, management and organizational skills and belongs to the external environment and internal corporate enterprises industry characteristics affecting the success of corporate management of the business. And lacked sufficient consideration of the various technical characteristics present in the form of joint research and industry. Finally, there is a limit of generalizations about other industries.

An Experimental Study on the Swimming Performance of Pale Chub(Zacco platypus) (피라미의 유영특성에 관한 실험적 연구)

  • Park, Seong-Yong;Kim, Seo-Jun;Lee, Seung-Hwi;Yoon, Byung-Man
    • Journal of Korea Water Resources Association
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    • v.41 no.4
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    • pp.423-432
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    • 2008
  • The local migration or movement behavior of fishes in streams are related to feeding, spawning, growing, dispersing, and refuging. The pale chub (Zacco platypus) is a dominant species that migrates locally and inhabits in river and stream in Korea. However, dams, weirs, culverts and other regulatory structures are physical barriers that limit fish movement and fragment habits and populations. If main stream and off-channel habitats are connected with culverts, they would restrict the small fish as pale chub movement due to the high flow velocities and low depths. But in Korea, there is no experimental study to evaluate the swimming performance of species in Korea. Therefore, it is difficult to proposed that design guidelines for pass fishes through culverts. The purpose of this experimental study is to evaluate the swimming performance of pale chubs. A series of swimming performance test has been used in both of the fixed velocity and the incremental velocity methods in an experimental flume. As a result, the critical swimming speed for pale chub(body length 8.9 cm) was found to be about 0.7 m/s. Therefore, the flow velocity for culvert design in the low flow condition should not be exceed the its swimming ability, especially 0.7 m/s for pale chubs(body length 8.9 cm). And the minimum depth for culvert design in the low flow condition should not be lower than the fish body height add a dorsal fin height.

Development of Detailed Korean Adult Eye Model for Lens Dose Calculation

  • Han, Haegin;Zhang, Xujia;Yeom, Yeon Soo;Choi, Chansoo;Nguyen, Thang Tat;Shin, Bangho;Ha, Sangseok;Moon, Sungho;Kim, Chan Hyeong
    • Journal of Radiation Protection and Research
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    • v.45 no.1
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    • pp.45-52
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    • 2020
  • Background: Recently, the International Commission on Radiological Protection (ICRP) lowered the dose limit for the eye lens from 150 mSv to 20 mSv, highlighting the importance of accurate lens dose estimation. The ICRP reference computational phantoms used for lens dose calculation are mostly based on the data of Caucasian population, and thus might be inappropriate for Korean population. Materials and Methods: In the present study, a detailed Korean eye model was constructed by determining nine ocular dimensions using the data of Korean subjects. The developed eye model was then incorporated into the adult male and female mesh-type reference Korean phantoms (MRKPs), which were then used to calculate lens doses for photons and electrons in idealized irradiation geometries. The calculated lens doses were finally compared with those calculated with the ICRP mesh-type reference computational phantoms (MRCPs) to observe the effect of ethnic difference on lens dose. Results and Discussion: The lens doses calculated with the MRKPs and the MRCPs were not much different for photons for the entire energy range considered in the present study. For electrons, the differences were generally small, but exceptionally large differences were found at a specific energy range (0.5-1 MeV), the maximum differences being about 10 times at 0.6 MeV in the anteroposterior geometry; the differences are mainly due to the difference in the depth of the lens between the MRCPs and the MRKPs. Conclusion: The MRCPs are generally considered acceptable for lens dose calculations for Korean population, except for the electrons at the energy range of 0.5-1 MeV for which it is suggested to use the MRKPs incorporating the Korean eye model developed in the present study.

Case Studies on Distributed Temperature and Strain Sensing(DTSS) by using an Optical fiber (광섬유 센서를 이용한 온도 및 변형 모니터링에 대한 현장응용 사례)

  • Kim, Jung-Yul;Kim, Yoo-Sung;Lee, Sung-Uk;Min, Kyoung-Ju;Park, Dong-Su;Pang, Gi-Sung;Kim, Kang-Sik
    • Proceedings of the Korean Geotechical Society Conference
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    • 2006.03a
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    • pp.86-95
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    • 2006
  • Brillouin backscatter is a type of reflection that occurs when light is shone into an optical fibre. Brillouin reflections are very sensitive to changes in the fibre arising from external effects, such as temperature, strain and pressure. We report here several case studies on the measurement of strain using Brillouin reflections. A mechanical bending test of an I beam, deployed with both fiber optic sensors and conventional strain gauge rosettes, was performed with the aim of evaluating: (1) the capability and technical limit of the DTSS technology for strain profile sensing; (2) the reliability of strain measurement using fiber optic sensor. The average values of strains obtained from both DTSS and strain gauges (corresponding to the deflection of I beam) showed a linear relationship and an excellent one-to-one match. A practical application of DTSS technology as an early warning system for land sliding or subsidence was examined through a field test at a hillside. Extremely strong, lightweight, rugged, survivable tight-buffered cables, designed for optimal strain transfer to the fibre, were used and clamped on the subsurface at a depth of about 50cm. It was proved that DTSS measurements could detect the exact position and the progress of strain changes induced by land sliding and subsidence. We also carried out the first ever distributed dynamic strain measurement (10Hz) on the Korean Train eXpress(KTX) railway track in Daejeon, Korea. The aim was to analyse the integrity of a section of track that had recently been repaired. The Sensornet DTSS was used to monitor this 85m section of track while a KTX train passed over. In the repaired section the strain increases to levels of 90 microstrain, whereas in the section of regular track the strain is in the region of 30-50 microstrain. The results were excellent since they demonstrate that the DTSS is able to measure small, dynamic changes in strain in rails during normal operating conditions. The current 10km range of the DTSS creates a potential to monitor the integrity of large lengths of track, and especially higher risk sections such as bridges, repaired track and areas at risk of subsidence.

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The Experiences of Trial Alternative Therapies for Cancer Patients (암환자의 대체요법 시행경험)

  • Go, Dock-Soon;Chung, Yeon-Kang
    • Journal of Home Health Care Nursing
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    • v.8 no.2
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    • pp.109-120
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    • 2001
  • This study has been done in order to help the people understand the cancer patients and provide the basic materials for the care of cancer patients by deeply understanding the living experience of the practice of alternative therapy for cancer patients. Data were collected with several in depth interviews and observations. Collected datas were analyzed by using phenomenological method of study by Giorgi (1970). The trial experience of alternative therapy for cancer patients has been classified into the one of having concerns, following, being infatuated, and coming out by pushing, and the experience of having concerns appeared as the meaning of the limit of modern medicine, despair, loneliness. hope, emotional support. dissolution of the feeling of uneasiness. the feeling of burden of the medical expense, self-treating, the subject of treatment. and indifference while the experience of following appeared as the meaning of blind following, temptation, going outside to look for something, wandering. following unconditionally, advise of the professionals, mistaken belief. self-abandonment, powerlessness. disconnection of dialogue with the medical staff. elevation of immunity, strengthening the physical power, absence of the source of examined information, clinging, self-responsibility. the experience of being infatuated appeared as the meaning of thorough trial. affirmative experience. devotion. diverse efforts, faithful trial. affirmative self-suggestion. change of the style of life. the feeling of burden of expense, being envious, bitter feeling toward the family, considering family, family discords, and difficulty of enforcement. The experience of coming out by pushing appeared as the meaning of waiting. self-reflection. maintaining the distance. cutting attachment, throwing the greed away, coming out by pushing. being thoughtful. accepting disease. individual difference of physical quality, and ambivalence. But they return to the experience of being concerned all over again in case of recurrence or metastasis of the disease even though they come out of such stage, and they always have ambivalence even in the condition with no recurrence and metastasis. In conclusion, the trial of alternative therapy for cancer patients could be explained as the adaptive behavior to the disease which is difficult to be cured. the cancer. The cancer patients are exposed to the side effects and harm without the examined information resources. Therefore the nurse should well aware of the alternative therapy and be able to do the appropriative management through the open communication with the patients who are under the trial of alternative therapy.

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Habitat Selection and Environmental Characters of Acheilognathus signifer (묵납자루, Acheilognathus signifer의 서식지 선택과 환경특성)

  • Baek, Hyun-Min;Song, Ho-Bok
    • Korean Journal of Ecology and Environment
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    • v.38 no.3 s.113
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    • pp.352-360
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    • 2005
  • Acheilognathus signifer is distributed widely in high density in the Naechon-stream. The order of this-stream was 2 ${\sim}$ 4 and the water width is wide but the depth is relatively shallow and the sinuosity is 1.83, which indicates a meandering stream. The water width/stream width ratio is 1.59, which suggests moderate entrenchment. Naechon-stream was classed as B type by Rosgen (1995). The natural habitat of A. signifer is a slow flow velocity pool, like a backwater pool, which is made up of piled up boulders that restricts the flow of water. The stream bed is made up of boulders and sands that enable the spawning host to inhabit. A. signifer selects a microhabitat where the boulders furnish hiding places. The Habitat of A. signifer is strongly affected by the existence or not there of U. douglasiae sinuolatus. After hatching from the mussel, A. signifer inhabits the surface of the water. It then moves to the low layer once it acquires swimming ability. While A. signifer inhabits the river in summer, A. signifer moves to the deeper layers in winter, where there are the refuge like rocks and boulders. In spring A. signifer moves from the deep water to the river line where the mussels reside.