• Tunnel and Underground Space
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• v.5 no.3
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• pp.240-250
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• 1995

Microcrack development in the macheon gabbro, the Sangju sandstone and the Jungsun marble due to fatigue stresses was investigated using differential strain analysis and microscopic observations from fluorescent-dyed thin sections. In the Macheon gabbro, various types of cracks, including gran boundary cracks, cleavage cracks, intragranular cracks adn intergranular cracks were developed. However, only grain boundary cracks were produced in the Sangju sandstone and the Jungsun marble due to fatigue stress. Many microcracks were produced due to fatigue stresses in the macheon gabbro. However, few microcracks were produced in the Sangju sandstone and the Jungsun marble. Fatigue stresses produced new microcracks in the Junngsun marble and the Macheon gabbro, but only pre-existing grain boundary cracks were lengthened in the Sangju snadstone. Most microcracks were produced within a few tens of numbers of cyclic loading, indicating that rocks under fatigue stresses will be damaged at the early stage of cyclic loading.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.884-889
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• 2005

A lot of landslides were occurred in Gangnung, Macheon and Geochang areas by Typhoons such as RUSA(2002) and MEAMI(2003). Soil properties of these areas are investigated regarding geological conditions in this study. The shallow plane failure were occurred in Gangnung and Geochang areas, whereas the deep circle failure were occurred in Macheon area. The matrix in Gangnung and Geochang areas was composed of Granite, and the matrix in Macheon area was composed of Gabbro. The disturbed and undisturbed soils were sampled in these areas. As the results of laboratory tests using sampled soils, the coefficient of permeability in Granite region is lower than that in Gabbro region. In the cases that the silt and clay contents are included less than 4% for the soils of Granite region and less than 7% for the soils of Gabbro region, the coefficients of permeability are rapidly increased for both soils. In addition, the simple equations for predicting the coefficients of permeability are proposed using the effective particle size and the silt and clay contents according to geological condition.

• Journal of Environmental Science International
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• v.7 no.3
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• pp.275-280
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• 1998

In order to clarify the seasonal composition and abundance of zooplankton commuuty In Macheon Bay. the study was carried out trimonthly during the period from April 1996 to January 1997. 1 species of Cnidana. 1 species of Annelida, 2 Ima of Moiluscs.3 species of Rotifera, 4 species and 4 larspecies was Tintinnopsis beroidea In the spring, Copepodite In the summer, Tintinnopsis beroidea In the autumn and Ceratium risus In the winter. Abundance of zooplankton ranged firom 4.720 to 41,215 Inds./1 It was high In the summer (41,215 inds./l) and low In the spring 14,720 inds./l). Dominant index ranged from 0.133 (in the spring) to 0.551 (in the winter). Species diversity inden ranged from 1.114 (in the winters to 1.996 (in the spring).

• The Journal of the Petrological Society of Korea
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• v.16 no.3
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• pp.162-179
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• 2007

Macheon Layered Intrusion (MLI) which intruded into Precambrian gneiss complex of the northern Jirisan area, southeastern part of Youngnam (or Sobaeksan) Massif, is a layered mafic-ultramafic complex of Triassic age (ca. 223 Ma). The MLI is divided into Layered Series and Laminated Series. Layered Series is subdivided into Central Zone (Lower Zone) consisting of olivine gabbros and Peripheral Zone (Middle or Upper Zone) consisting of hornblende gabbros based on the type of cumulus texture and the main mafic phase. The Central Zone of Layered Series comprises thinly laminated olivine gabbros and uniform or thickly laminated coarse olivine gabbros which consist of mela-gabbro, troctolite, leuco-troctolite, and anorthositic rocks. Laminated Series is also subdivided into quartz-bearing biotite-pyroxene gabbros and homblende diorite and both have variable amount of interstitial quartz and microcline. Laminated series display moderately to slightly developed igneous lamination which is defined by the planar alignment of lath-shape plagioclases. Chilled margin of quartz-bearing biotite-pyroxene gabbro with surrounding Precambrian gneisses insists shallower intrusion of more felsic cognate magma evolved in the deep a little later. Rocks of Layered Series have orthocumulus to adcumulus olivine, adcumulus to intercumulus plagioclase, and intercumulus to heteradcumulus pyroxene and hornblende. Magmatic modally grading, folding, and cross-lamination are not rarely occurred in thinly layered rocks. These textural characteristics define main mechanisms of the formation of layered and laminated structure in mafic-ultramafic rocks of Macheon Layered Intrusion are gravity settling and in-situ crystallization associated with slumping and density current.

• Journal of The Korea Institute of Healthcare Architecture
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• v.25 no.3
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• pp.85-97
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• 2019

Purpose : The purpose of this study is to evaluate the remodeling effectiveness on old town in Songpa-Gu, Macheon-Dong in the point of elderly living. Methods : Main research method is interview with older residents living in Macheon-Dong. The surveyed district of old town is divided into two groups, one is experimental group and the other is control group. The interviews have been conducted two times; before the remodeling(September, 2017) and after the remodeling(May, 2019). Total number of questionnaire is about 400. Correlation analysis, T-test, regression analysis have been used for the interpretation of collected data. Results : The number of accident and road confusion of older residents in experimental group have been decreased after remodeling. Most preferred space is resting area, and older residents considers convenience and practicality as more important. 47.7% of respondents have evaluated dwelling site as good after remodeling. Implication : This study sends a meaningful message in that remodeling effect of old town has been analyzed quantitatively and dwelling area regeneration project of old town is positive for the improvement of dwelling environment.

• The Journal of the Petrological Society of Korea
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• v.15 no.1 s.43
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• pp.1-9
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• 2006

Sr isotopic compositions are determined from the syenite of Sancheong area, yielding age of $211{\pm}23(2\sigma)$ Ma and $^{87}Sr/^{86}Sr$ initial ratio of $0.70598{\pm}0.00060$. Such result confirms that Sancheong syenite was emplaced during the Mesozoic around the Triassic-Jurassic boundary. Rather low initial $^{87}Sr/^{86}Sr$ ratio suggests insignificant influence of old crustal materials. There are strong contrast in rock types of plutonic associations between Sancheong-Macheon area and adjacent Hamyang-Geochang area to the north, i.e. syenite-diorite-gabbro and granite-granodiorite respectively. $^{87}Sr/^{86}Sr$ initial ratios also show distinction between these areas. Such differences suggest regional contrast in tectonic environments between them.

• Journal of The Geomorphological Association of Korea
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• v.18 no.4
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• pp.193-202
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• 2011

Kompsat EOC-1 imagery, high resolution air-photo imagery and Shalstab model were used to analyze the geomorphic characteristics of the place of debris flow occurred by typhon "RUSA" in 2002, Macheon-Myen, Gyeongsang prefecture, Republic of Korea. On gully-head over 35 degree of slope angle, almost debris flow started, where slope angle is more than internal friction angle. The result simulated by Shalstab model presented larger vulnerable area to debris flow than the area where debris flow really occurred, this error would be attributed to the assumption for steady-state condition with full saturated surface. To predict the debris flow accurately, further study for rainfall and soil water flow will be needed.

• Korean Journal of Plant Taxonomy
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• v.44 no.1
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• pp.1-5
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• 2014

The newly recorded species, Crepidomanes schmidtianum (Zenker ex Tasch.) K. Iwats. (Hymenophyllaceae) was collected from forests in Mt. Jirisan, Baegmu-dong, Macheon-myeon, Hamyang-gun, Gyeongsangnam- do. C. schmidtianum (vernacular name: 'Du-me-goe-bul-i-kki') was distinguished from other Korean congeners of the genus Crepidomanes by having pseudo-vein, almost wingless in stipe, and involucres cup shaped with dilated. A new Korean name, 'Du-me-goe-bul-i-kki', was given based on its habitat. Descriptions and illustrations of this taxon and its photograph in the habitat are provided along with a key to the species of Crepidomanes from Korea.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.1092-1099
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• 2009

Landslide researches are divided to a method of interrelationship for various factors, method of predicting landslide possibility, and method of estimating landslide risk which are occurring landslides in the natural slope. Most of landslides occurred in natural slope are caused by a heavy rainfall in summer season. Weathered soil layer located in upper side of rock mass was occurred. As well as, they are announced to have an influence to geometry, geology, soil characteristics, and precipitation in the natural slope. In order to investigate and interpret the variety of landslides from field investigation to risk analysis, landslide analysis process due to geotechnical and geological opinions are systematically demanded. In this research, the study area is located in Macheon area, Gyeongsangnam-do and performed the landslide investigation. From the results of landslide investigation and analysis, optimized standard model based on natural landslide is proposed to high technical method of landslide investigation and interpretation.

• Journal of The Korean Association For Science Education
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• v.34 no.3
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• pp.295-301
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• 2014

The purpose of this study is to investigate the difficulties of teachers and students on the unit about 'measuring weight.' In this research, we have acquired data about teachers through survey, interview, and self-reflection journals, at the same time we have collected information on the students through survey, assessment test, and interview. We have extracted the difficulties from analysis with constant comparison method. In addition, we have analysed the curriculum of science and mathematics to know the leaning sequence. The analysis had been checked up by experts in science education. The result of the study is as follows: The difficulties of teachers are from the lack of teachers' descriptive knowledge, disorder of conceptual hierarchy in the curriculum, poor experimental instruments, and low psychomotor skill of students. The difficulties of students are from common misconceptions, opaque concepts, lack of manipulation skill, insufficiency of mathematical ability, difficulty of application of principles to the real situation, and lack of problem-solving ability. In addition, teachers have recognized that students face more difficulties in experiment class, while students think that they face more difficulties in conceptual understanding class.