• Journal of the Earthquake Engineering Society of Korea
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• v.22 no.3
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• pp.219-224
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• 2018

The The purpose of this study is to investigate the actual liquefaction occurrence site in Pohang area and to analyze the ground characteristics of Pohang area using the data of the National Geotechnical Information DB Center and to calculate the liquefaction potential index. Based on the results, the distribution of soil classification in Pohang area and the risk of liquefaction under various earthquake accelerations were prepared. As a result of the study, soils in Pohang has the soil characteristics that can cause the site amplification phenomenon. In the analysis through liquefaction hazard maps under earthquake scenarios, it is found that the liquefaction occurred in the area of Heunghae town is more likely to be liquefied than other areas in Pohang. From these results, it is expected that the study on the preparation of liquefaction hazard maps will contribute to the preparation of countermeasures against liquefaction by predicting the possibility in the future.

• Journal of Korean Elementary Science Education
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• v.35 no.1
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• pp.78-88
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• 2016

The purpose of this study was to examine the effects of science lesson with the application of Flipped Learning on science academic achievement and scientific attitude of students. The experimental group was composed of 50 students and the comparative group was composed of 50, both in $6^{th}$ grade. The two groups were statistically equivalent in their science academic achievement and scientific attitude when pre-tests were conducted. The experimental group received science instruction applied with Flipped Learning and the comparative group took typical science lesson according to a teacher's guide. The results of this study can be summarized as follows: First, the science lesson with the application of Flipped Learning was more significantly effective in improving students' science academic achievement than traditional science lesson. Second, the science lesson combined with Flipped Learning enhanced scientific attitudes of students with meaningful difference more than typical science lesson. Third, a survey research was conducted to the experimental group about their cognition on the lessons with the application of Flipped Learning. Many students had positive thoughts on this lesson and they thought the lesson was very interesting and understandable.

• The Journal of Engineering Geology
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• v.19 no.4
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• pp.459-474
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• 2009

By the analysis of discontinuity at the outcrop and lineament on the satellite image, the joints have deeply relationship with the lineaments. The joint spaces at the drilling core are mostly 1~20 cm but at the rhyolite which is distributed near fault they have more closely. These volcanic rocks belong to the subalkaline series tuff, rhyolite, basalt in the study area from the diagram of $Nb/Y-Zr/TiO_2$. The composition diagram of Hf/3-Th-Nb/16 show destructive plate-margin basalt and their differentiates. The environment of formation of volcanics are normal continental arc. Most of LREE show high enriched pattern but HREE show depleted pattern. The K/Ar age of intermediate volcanics, tuff, rhyolite, crystal tuff are 55.3Ma, 77.25 Ma~91.22Ma, 63.16~64.39Ma, 54.49 Ma respectively.

• Geophysics and Geophysical Exploration
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• v.15 no.2
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• pp.51-56
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• 2012

One of the most critical and essential procedures in the interpretation of gravity and magnetic data is to separate the anomaly due to the specific geologic structure from the summation of effects from a broad variety of geologic sources, especially those of different depths. Separation of the residual anomaly from the regional field is the most simple case of the vertical separation. If the anomaly due to a layer of specific depth can be separated or the depth of the separated layer can be quantitatively determined, it may deserve the separation-sounding. We suggest a wavelength filter whose cutoff frequency is determined by log-power spectrum analysis, as a separation-sounding filter. We applied this filter both to synthetic and real gravity data acquired at Heunghae area, and compared the results with those of Jacobsen's upward continuation filter. These showed that the proposed separation-sounding filter could be a useful tool for interpretation of the vertical geologic structure by stripping the gravity effects of geologic sources down to the desired depth.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2001.12a
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• pp.122-122
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• 2001

쌀과 같은 곡류는 전분질을 당분으로 전환시켜 술을 제조하여야 하므로 미생물이 생성하는 효소가 필요한데 그 효소원이 누룩이며 누룩은 주류의 품질이나 생산량에 영향을 미치는 가장 중요한 요소라고 할 수 있다. 본 연구는 전국44개 지역의 누룩에서 순수 분리된 89종의 곰팡이 중 효소역가와 당화력이 비교적 뛰어난 10종(Aspergillus sp. SH-412 Heunghae, Aspergillus sp. SH-422 Ulsan, Rhizopis sp. SH-606 Imdeok, Aspergillus sp. SH-607 Yhesan, Aspergilus sp. SH-613 Wolseong, Rhizopus sp. SH-654 Uncheon, Aspergillus sp. SH-660 Jeonkok, Aspergillus sp. SH-667 Dongseong, Aspergillus sp. SH-669 Uncheon, Aspergillus sp. SH-696 Daecheon)과 대조균주로 Aspergillus kawachii CF1002 그리고 효모 Saccharomyces cerevisiae를 사용하셨으며 탁주제조 중 균주별 술덧의 산도, 환원당, 아미노산도와 제조된 완성주의 유기산, 유리아미노산, 유리당, 휴젤유 및 색도를 HPLC, GC Mass, 색차계로 측정한 결과 다음과 같은 결론을 얻었다. 균주별 술덧의 주정도는 모든 실험구에서 Aspergillus kawachii보다 높았으며 특히 Aspergillus sp. SH-422는 14.9%로 가장 수율이 좋았다. 환원당은 Aspergillus sp. SH-613이 0.49%로 가장 높았고 Aspergillus sp. SH-422는 0.37%로 가장 낮았으며 산도는 시간의 경과에 따라 감소했으며 술덧 발효중 아미노산도는 시간의 경과에 따라 약간 상승 후 다소 낮아지는 경향을 보였다. 각 균주별 술덧의 유기산은 tataric acid, malic acid, succinic acid, lactic acid, acetic acid가 검출되었으며 lactic acid 함량이 2.0∼3.2g/100ml로 가장 많이 검출되었다. 유기산은 Aspergillus sp. SH-669가 가장 높게 확인되었으며 Aspergillus sp. SH-607이 가장 낮게 분석되었다. 술덧의 주 아미노산은 histidine, alanine, glutamic acid, leucine, tryptophan순으로 검출되었으며 특히 alanine은 주류에 단맛을 주는 성분으로 모든 실험구에서 많은 양이 검출되었다. 각 균주별 술덧의 유리당은 glucose가 가장 많이 검출되었으며 Fusel oil은 iso-butyl alcohol과 iso-pentyl alcohol 이 가장 많이 검출되었다. 한편 균주별 술덧의 색차를 측정한 결과 L값은 63.33∼41.98, a값은 0.09∼-3.47, b값은 17.41∼4.90으로 나타났다.

• Economic and Environmental Geology
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• v.25 no.2
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• pp.167-177
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• 1992

The gravity measurement has been conducted at 53 and 34 stations with an interval of 1~1.5 km along the national roads of about 47 km and 34 km running from Duksungri to Yangpori and from Angangri to Byungpori, Kyungsangbookdo, respectively. The subsurface geology and geologic structure of Tertiary Pohang and Janggi basins along two survey lines are interpreted quantitatively by applying Fourier series and Talwani methods for Bouguer gravity anomaly. The depths of Conrad discontinuity vary from 11.8 to 12.5 km and 11.5 to 13.2 km along the survey lines between Duksungri and Yangpori, and Angangri and Byungpori, respectively. The depths of pre-Cambrian Gneiss complex underneath Kyungsang Supergroup vary from 3.8 to 4.2 km and 3.8 to 4.6 km along the survey lines between Duksungri and Yangpori, and Angangri and Byungpori, respectively. Massive granite bodies which are not exposed along the survey line between Duksungri and Yangpori are distributed on a large scale at the subsurface between Duksungri and Ochun, and Daegokri and Yangpori. Along the survey line between Angangri and Byungpori, it is exposed at Angangri, and extends underneath Chungrimdong, Pohang city. Andesite is distributed on a small scale underneath Pohang city and Ochun. The thicknesses of Tertiary Yonil and Janggi Groups are 0.2~0.9 km and 0.1~0.5 km, respectively. The Tuffaceous rocks which are the lowest formation of Tertiary sedimentary rocks are distributed with the thickness of 0.2 km at the surface and between Kyungsang Supergroup and Yonil or Janggi Groups. The Yonil and Janggi Groups are in fault contact by a fault running through Ochun and Chungrimdong, Pohang city. Two other faults are newly found near Heunghae-eup and Hyungsan river.

• Journal of the Korean Society of Safety
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• v.35 no.5
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• pp.106-114
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• 2020

The two major trends that have emerged in recent years in relation to disaster recovery and recovery are 'regional infrastructure', 'regional leadership' and 'community recovery'. In the former case, it is to avoid disaster recovery and recovery by using external personnel and resources, and to maximize the resources in the area under the initiative of the residents of the affected area. And through this process, it is to prepare a new growth engine for disaster-affected areas. In addition, the latter expands disaster recovery targets to the general population living in affected areas and is not limited to victims. Through this, we can expect to recover the 'community' beyond the individual's recovery. In the Ansan of Gyeonggi-do, where many families of 'Sewolho' live, and in the Heunghae-eup of Pohang, Gyeongbuk-do, where the damage was severe, projects are underway to restore communities. And In these areas local activists and civic groups are actively utilized to efforts are being made to increase efficiency. Nevertheless, in the case of the community recovery program being promoted in Korea, there are limitations that it can be promoted only on the basis of special laws and that participation of various actors is necessary. This study intends to propose the limitations of current projects and ways to solve them by analyzing domestic and foreign cases related to the community recovery program for disaster-affected communities using local resources. we suggest two way. One is the relaxation of the national dependence of the community recovery program, and the other is to expand the area of disaster relief through.

• Journal of the Korean Geotechnical Society
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• v.36 no.9
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• pp.5-20
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• 2020

In 2017, after the Pohang earthquake, liquefaction phenomena were firstly observed after the observation of domestic earthquake by epicenter. In this study, various in-situ tests and laboratory tests were performed to determine the dynamic properties in (1) Songlim Park, (2) Heunghae-eup, Mangcheon-ri and (3) Heungan-ri, Pohang. As a site investigation, the standard penetration test (SPT), cone penetration test (CPT), multichannel analysis of surface wave (MASW), density logging, downhole test, and electrical resistivity survey were performed. In addition, cyclic triaxial test against sampled sand from site was also conducted. Based on the result, high ground water level and loose sand layer in shallow depth were observed for all sites. In addition, liquefaction resistance ratio of soil sampled from Songlim park was lower than those of Jumunjin sand, Toyoura sand, and Ottawa sand.

• Journal of the Korean earth science society
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• v.43 no.1
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• pp.188-198
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• 2022

Some deep faults do not reach the ground surface and are seldom recognized. Gokgang Fault area in the east of the Heunghae area of the Pohang basin has been selected to confirm the feasibility of the Horizontal-to-Vertical Spectral Ratio (HVSR) approach to identify blind faults. Densely spaced microtremor data have been acquired along two lines in the study area and processed to obtain resonance frequencies. An empirical relationship between the resonance frequency and the bedrock depth was proposed using borehole data available in the study area. Resonance frequencies along two lines were then converted to bedrock depths. The resulting depth profiles show significant lateral variations in the bedrock depth. As expected, considerable variation in the resonance frequency is observed near the Gokgang fault. The depth profiles also present additional significant variations in the resonance frequencies and the bedrock depths. The feature is presumably related to a blind fault that is previously unknown. Therefore, this case study confirms the feasibility of the HVSR technique to identify faults otherwise not recognized on the surface.

• The Journal of the Petrological Society of Korea
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• v.18 no.2
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• pp.115-135
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• 2009

We have studied general orientational characteristics of microcracks distributed in Tertiary crystalline tuff from the northeastern part of the Gyeongsang Basin. 108 sets of microcracks on horizontal surfaces of 6 rock samples from Heunghae-eup and Cheongha-myeon, Pohang-si areas were distinguished by image processing. Those microcrack sets show a distinct linear array in 38 images. Whole domain of the directional angle(${\theta}$)-frequency(N) chart for crystalline tuff can be divided into 20 domains in terms of the phases of the distribution of microcracks. From the related chart, microcrack sets show preferred orientation which are coincident with the direction of vertical common joints. Consequently, the potential for macroscopic vertical joints in a rock body can be inferred from the directional angle showing high frequency in each domain of the related chart. This joint pattern is nearly the same in Mesozoic granites from Seokmo-do, Gwanghwa-gun. From the rose diagram for orientations of microcrack in crystalline tuff, orientations of dominant sets of microcracks in terms of frequency orders reflect representative orientations of maximum principal stress acted on crystalline tuff. Meanwhile, orientations of microcracks in crystalline tuff were compared with those of open microcracks in Bulgugsa granites from the southwestern part of the Gyeongsang Basin, and vertical rift/grain planes from Mesozoic granite quarries in Korea. In regional distribution chart, the agreement of distribution pattern between above two types of microcrack sets and vertical planes suggests that microcrack systems developed in crystalline tuff probably occur regionally in Mesozoic granites in Korea.