• Economic and Environmental Geology
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• v.23 no.4
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• pp.453-463
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• 1990

The Yechon shear zone developed by strike-slip movement was formed in a relatively high temperature condition just after the Jurassic syntectonic granites had been emplaced during Daebo Orogeny. Post-emplacement formation of the shear zone is favored by continuity of foliations and lineations within and without the granites, development of mylonitic structures in the wallrocks, deformation of pegmatite and felsite dikes, and pretectonic growth of porphyroblasts in the wallrocks. A variety of shear sense indicators in the shear zone are predominantly observed in the intensely to extremely deformed rocks. They show that bulk non-coaxial detormation has occurred, and that the sense of shear is consistently dextral with S-C fabrics, grain shape fabrics, asymmetric porphyroclast systems, mica fish, asymmetric extension structures and quartz C-axis fabrics.

• Geotechnical Engineering
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• v.13 no.4
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• pp.149-162
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• 1997

A series of torsion shear tests were performed to study the strength characteristics of sand under various stress paths during rotation of principal stress. These results can be classified into two groups of 25cm and 40cm according to the height of specimen, and toy que was applied only in the clockwise direction. In this study, strength characteristics of sand for the principal stress ratio in torsion sheartests were investigated and their results were compared with Lade's failure criterion. And the effect for specimen was considered. From the results of tests, friction angle of sand was affected by the deviatoric principal stress ratio $b:(\sigma_2 -\sigma_s)/(\sigma_2, -\sigma_3)$Failure strength of sand was determined not by the stress paths but by the current stress state. From comparison of specimens on 25cm and 40cm height, effect of end restraint could not be found. In the test where b is over 0.5 due to extension force, necking phenomenon by the strain localization was found.

• Journal of Life Science
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• v.25 no.6
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• pp.615-623
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• 2015

This study investigated the effects of dissolved cement powder on Zacco koreanus by analyzing morphophysiological changes. The gills exposed to dissolved cement powder developed abnormal shapes in their secondary lamellae and increased numbers of mucous cells after long-term exposure. Additionally, clubbing, edema, and exfoliation of the epithelial cells were observed in the secondary lamellae. In the kidney tissue, the space in Bowman’s capsule was widened, and in the integument tissue the arrangement of the dermis was irregular due to the thinned epidermis. These results suggest that long-term exposure to cement powder can significantly affect morphological change, resulting death. The activities of antioxidant enzymes and LDH tended to increase commensurately with the duration of cement exposure. It was concluded that up-regulated proteins were the stress proteins involved in myofibrillar-protein production and down-regulated proteins were involved in glycolysis and energy metabolism after the integument’s exposure to cement. According to these results dissolved cement powder is a serious threat to the survival of fish because it causes morphological changes and weakens physiological activity in Z. koreanus tissues.

• Journal of the Korean Society for Nondestructive Testing
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• v.20 no.6
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• pp.481-489
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• 2000

A time-frequency analysis method was developed to analyze the dispersive waves caused by impact loads in structural members such as beams and plates. Stress waves generated by ball drop and pencil lead break were recorded by ultrasonic transducers and acoustic emission (AE) sensors. Wavelet transform (WT) using Gabor function was employed to analyze the dispersive waves in the time-frequency domain, and then to find the arrival time of the waves as a function of frequency. The measured group velocities in the beam and the plate were compared with the predictions based on the Timoshenko beam theory and Rayleigh-Lamb frequency equations, respectively. The agreements were found to be very good.

• Journal of Science and Technology Studies
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• v.19 no.3
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• pp.1-49
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• 2019

First proposed by Paul Crutzen and Eugene Stoermer in 2000, the concept of the Anthropocene has had staggering repercussions in a variety of disciplines. In response to the Anthropocene narrative as a problematization of the eco-ontological emergency that humanity is confronted with in the 21st-century, I will deal with the following theoretical themes in this article. Firstly, I will analyze the central agendas underlying the Anthropocene discourse: the expansion of human agency into the planetary level and the possibility of unprecedented catastrophes in the near future. Secondly, I will propose to address the Anthropocene discourse as problem-assemblage. Thirdly, I will examine Clive Himilton and Dipesh Chakrabarty's theses in order to understand the shock that was brought to bear on the humanities and social sciences by the Anthropocene narrative. Fourthly, I will reinterpret the allegory of the angel appearing in Benjamin's Theses on the Philosophy of History to explore new possibilities of transformative becoming of the subjectivity, focusing on the concept of patiency. Finally, I will present the concept of reflexive catastrophism.

• The Journal of the Petrological Society of Korea
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• v.19 no.3
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• pp.227-244
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• 2010

Abundant spinel lherzolite xenoliths showing distinctively different textural types such as protogranular, porphyroclastic, and mylonitic texture are trapped in the basaltic rocks from southeastern part of Jeju Island. These xenoliths show the textural spectrum from coarse-grained protogranular through porphyroclastic with bimodal grain size to fine-grained and foliated mylonitic texture. They tend to decrease in grain sizes and show more linear grain boundaries and more frequent triple junctions from protogranular through porphyroclastic to mylonitic. Spinel has different occurrence mode according the textural type. Spinel is always associated with orthopyroxene in protogranular texture, whereas it is scattered and independent of orthopyroxene in mylonitic texture. Additionally, porphyroblast from porphyroclastic and mylonitic textures has internal deformation features such as kink band, undulatory extinction and curved lamella, whereas neoblast is strain-free. These textural features indicate increasing degree of static/dynamic recrystallization from protogranular through porphyroclastic to mylonitic texture. The mg#[$=100{\times}Mg/(Mg+Fe_t)$] of olivine, orthopyroxene and clinopyroxene is relatively constant (ol: 88-91; opx: 89-92; cpx: 89-92) regardless of textural differences. The mg# of constituent minerals, NiO content (0.3~0.4 wt%) and MnO content (0.1~0.2 wt%) of olivine are similar to those of mantle xenoliths worldwide, also indicating that studied spinel lherzolite xenoliths were mantle residues having experienced 20~25% partial melting. The geochemical and textural characteristics have close relations showing that LREE and incompatible trace elements content of orthopyroxene and clinopyroxene increases from protogranular through porphyroclastic to mylonitic. These observations suggest that the studied mantle xenoliths experienced metasomatism by LREE enriched melt or fluid after partial melting, indicating a close relation between deformation and metasomatism. The metasomatism was possibly confined to narrow shear zones from where porphyroclastic and mylonitic textured xenoliths originated. These shear zones might favorably drive the percolation of LREE-enriched melts/fluids responsible for the metasomatism in the lithospheric mantle below the Jeju Island.

• The Korean Journal of Nuclear Medicine
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• v.38 no.5
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• pp.338-343
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• 2004

Purpose: The purpose of this study was to develop a small animal PET using dual layer phoswich detector to minimize parallax error that degrades spatial resolution at the outer part of field-of-view (FOV). Materials and Methods: A simulation tool GATE (Geant4 Application for Tomographic Emission) was used to derive optimal parameters of small PET, and PET was developed employing the parameters. Lutetium Oxyorthosilicate (LSO) and Lutetium-Yttrium Aluminate-Perovskite(LuYAP) was used to construct dual layer phoswitch crystal. $8{\times}8$ arrays of LSO and LuYAP pixels, $2mm{\times}2mm{\times}8mm$ in size, were coupled to a 64-channel position sensitive photomultiplier tube. The system consisted of 16 detector modules arranged to one ring configuration (ring inner diameter 10 cm, FOV of 8 cm). The data from phoswich detector modules were fed into an ADC board in the data acquisition and preprocessing PC via sockets, decoder block, FPGA board, and bus board. These were linked to the master PC that stored the events data on hard disk. Results: In a preliminary test of the system, reconstructed images were obtained by using a pair of detectors and sensitivity and spatial resolution were measured. Spatial resolution was 2.3 mm FWHM and sensitivity was 10.9 $cps/{\mu}Ci$ at the center of FOV. Conclusion: The radioactivity distribution patterns were accurately represented in sinograms and images obtained by PET with a pair of detectors. These preliminary results indicate that it is promising to develop a high performance small animal PET.

• Applied Microscopy
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• v.29 no.2
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• pp.137-147
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• 1999

Comparative differences between the fine structure of cultured LL/2 cell in vitro and tumor cells in vivo which were induced in the lung by inoculation of LL/2 cells to C57 BL/6 mouse via tail vein during 21 days are not observed except for cell configuration which was changed spindle shape into oval shape. At first tumor cells appeared at lymphatic nodules and around capillary in the lung. Tumor cells divided actively by mitosis, so they became tumor nodules. The pulmonary aveoli around tumor nodules were observed somewhat flattened in shape but the cells in the aveoli appeared to be in normal condition. Furthermore the normal lung cells were observed in the tumor nodules and some apoptotic tumor cells appeared in the large tumor nodules. A lot of neutropiles were observed in the aveoli and tumor nodules of C57 BL/6 mouse lung after inoculation 22 days and 31days.

• 대한공업교육학회지
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• v.31 no.2
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• pp.203-232
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• 2006

The purposes of this study are to examine the effects of learning, which was applied TRIZ's 40 inventive principles, on the improvement of learners' creativity and to offer basic information that would be necessary to study on Inventive Education in Technology Education. In order to achieve the purposes, objects were divided into two groups, experiment group(74 students) and control group(67 students), who were from B Middle school in Daejeon. Creativity Self-Assessment and Student Inventive Rating Scale were used as tools for research so that we could find the homogeneity in two groups. An applied design method was nonequivalent control group pretest-posttest design. This study was performed for 2 hours on the 1st and the 3rd Saturday in every month from the 3rd week of March, 2006 to the 3rd of July of 2006, and total researching period was 9 weeks. In that time, the students were required to learn 40 inventive principles. The results from this study are as below. (1) Applying TRIZ's 40 inventive principles had a positive effect on students' CQ(creative quotient), as influencing on the subordinate factors of creativity, such as, originality, germinal, trasformational, value, attraction, expressive power and organic systemicity. However it didn't have any effect on adequateness, properness, merit, complex and elegance. (2) Applying TRIZ's 40 inventive principles had a significant effect neither on CQ by sex, nor on the subordinate factors of creativity, except for originality and expressive power. Based on the results of the experiment, below suggestions were made to promote the application of TRIZ's 40 inventive principles to Technology Education. (1) Although this study was performed by using development activities, it is necessary to study more systemically to apply 40 inventive principles to regular subject in Technology Education. (2) As creativity was very important in Technology Education, there should be studies on the various types of inventive principles and techniques for Inventive Education in Technology Education.

• The Journal of the Korean bone and joint tumor society
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• v.9 no.1
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• pp.1-11
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• 2003

Purpose: To analysis of the result of the treatment of metastatic diaphyseal fracture of the humerus with closed interlocking intrameduallry nailing. Materials and Methods: Among surgically treated 29 patients with pathologic or impending fracture of diaphysis of the humeurs, 13 patients (16 cases) treated with closed intramedullary interlocking nail were selected for the study. The final result of pain relief and functional recovery was evaluated by modified rating system of Perez et al. Results: Primary cancer was diagnosed after fracture was developed in 2 patients and pathologic or impending fracture was occurred average period of 28.9 months after primary cancer was diagnosed. The main primary malignancies were multiple myeloma, lung cancer and breast cancer. Mean survival after humeral metastasis was 11.7 months. The final result was superior to fair in 13 of 16 cases, and poor in 3 cases with progression of tumor spread or distant dissemination to the ipsilateral fingers. Except the latter 3 patients and other 3 patients, who died before 3 months postoperatively, bony union was achieved in 10 cases. There were no complications related to surgery. Conclusion: Closed interlocking intrameduallry nailing is accomplished with brief operative time, small amount of bleeding and provides immediate stability with resultant early return of function to the arm. Additionally it allows early postoperative irradiation. However, some of our cases shows that intramedullary nailing can accelerate tumor spread and metastases elsewhere, so that serious consideration must be given in planning this treatment. In conclusion, the functional status before fracture, life expectancy, type of tumor and extent of involvement should be carefully considered to decide operative treatment of metastatic disease.