• The Journal of Engineering Geology
• /
• v.23 no.4
• /
• pp.363-373
• /
• 2013

This study investigates the dispersion and behavior of Au and heavy metals in the water system (soil, AMD and stream sediment) at the abandoned Bonjeong gold mine, based on XRD, aqua regia, sequential extraction, and physico-chemical analyses. The XRD analyses targeted quartz and kaolinite in the mine waste soil and quartz and goethite in stream sediment. The physico-chemical analyses of AMD with increasing distance from water system showed that pH increased from 3.00 to 3.19 and Eh decreased from 450 to 396 mV. The Au content in AMD ranged from 0.68 to 0.97 mg/L upstream, but was not detected downstream. The Au content of stream sediment was 13.76 to 22.85 mg/kg. Sequential extraction from stream sediment revealed 10.84% exchangeable (STEP I), 11.09% carbonates (STEP II), 25.53% Fe-Mn oxides (STEP III), 26.62% organic matter (STEP IV), and 24.61% residual (STEP V).

• The Journal of Engineering Geology
• /
• v.22 no.4
• /
• pp.439-448
• /
• 2012

The aim of this study is to develop eco-friendly, fundamental technology for vegetative restoration of barren lands using green rehabilitation material, for the stabilization of abandoned mine debris slopes and depository slopes composed of rock fragments. It is expected that such methods would help to improve the negative view of artificial slopes that remain following mining activity, while also contributing to slope stabilization and prevention of the loss of rock fragments and the dispersion of tailings. We tested the tensile strength and tear strength of various materials, including commonly used natural coir material, natural fibers, and synthetic textile materials with enhanced durability. In conclusion, there is the possibility that natural coir can be used as an eco-friendly material in vegetation restoration, while its durability in natural conditions can be improved by controlling the degree of knot convolution and by antibacterial treatment against biodegradation.

• (The)Study of the Eastern Classic
• /
• no.48
• /
• pp.41-63
• /
• 2012

This research paper is aims to study the Zhu Xi school of Neo-Confucianism culture based on the Sosu seowon. Also This research paper is to discuss study and scholars correlation the Sosu seowon. The Sosu seowon is mainly made up of the Zhu Xi school of Neo-Confucianism development. The Sosu seowon was the cradle of scholars and bureaucrats. Scholars who study of orthodox Neo-Confucianism in the our country was respected academic spirit of An Whyang in the study of orthodox Neo-Confucianism. An Whyang is symbolic existence of the Sosu seowon. He knew well the importance of learning. He was the person to represent the Sosu seowon. Toegye and Sinje are handed down to the fundamental principle brought in on the orthodox Neo-Confucianism caused by An Whyang. This research paper is to based upon on academic spirit of An Whyang in the study of orthodox Neo-Confucianism. Scholars who study of orthodox Neo-Confucianism thought that the nation's happiness made appointment to a competent person learned the orthodox Neo-Confucianism caused by An Whyang related to the Humanism education.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.34 no.4
• /
• pp.1227-1240
• /
• 2014

Abandoned mines often cause environmental problems, such as alteration of landscape, metal contamination, and landslides due to a heavy rainfall. Geotechnical and rheological tests were performed on waste materials corrected from Imgi waste rock dump, located in Busan Metropolitan City. Debris flow mobility was examined with the help of 1-D BING model which was often simulated in both subaerial and subaqueous environments. To determine flow curve, we used a vane-penetrated rheometer. The shear stress (${\tau}$)-shear rate (${\dot{\gamma}}$) and viscosity(${\eta}$)-shear rate (${\dot{\gamma}}$) relationships were plotted using a shear stress control mode. Well-known rheological models, such as Bingham, bilinear, Herschel-Bulkley, Power-law, and Papanastasiou concepts, were compared to the rheological data. From the test results, we found that the tested waste materials exhibited a typical shear shinning behavior in ${\tau}$-${\dot{\gamma}}$ and and ${\eta}$-${\dot{\gamma}}$ plots, but the Bingham behavior is often observed when the water contents increased. The test results show that experimental data are in good agreement with rheological models in the post-failure stage during shearing. Based on the rheological properties (i.e., Bingham yield stress and viscosity as a function of the volumetric concentration of sediment) of waste materials, initial flowing shape (5 m, 10 m, and 15 m) and yield stress (100 Pa, 200 Pa, 300 Pa, and 500 Pa) were input to simulate the debris flow motion. As a result, the runout distance and front velocity of debris flow are in inverse propositional to yield stress. In particular, when the yield stress is less than 500 Pa, most of failed masses can flow into the stream, resulting in a water contamination.

• Journal of the Mineralogical Society of Korea
• /
• v.19 no.3 s.49
• /
• pp.129-138
• /
• 2006

In this study, we identified the secondary precipitates from Samsan-jeil and Sambong mine, Goseong, Gyeongnam by means of scanning electron microscopy, electron probe microanalysis and X-ray powder diffraction analysis. Copper sulfide minerals had been produced from the mines during last few decades, however they are not worked. White and blue precipitates were found at the downstream of mine rock dump at Sambong mine and green one was at Samsan-jeil mine. The white precipitate covered the host rock surface with thickness of $30{\mu}m$, and is a kind of diatom with $10{\mu}m$ in length and $3{\mu}m$ in width. It is a species Fragilaria constuens, which is contained a order Pennales(pennate diatom) and lives in fresh water. The blue precipitate is the alteration product of chalcopyrite. It resultes in the increase in the ratio Cu:Fe from 5 to 13. The green precipitate has worm-like morphology with $10{\sim}20nm$ in diameter and $200{\sim}300nm$ in length. It is mainly composed of secondary copper sulfate such as woodwardite. However, it could be formed by the activity of microorganism, because the copper content is more than any secondary copper sulfate reported in copper sulfide mine. In order to identity the green precipitate exactly, the further research is needed.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2015.05a
• /
• pp.336-336
• /
• 2015

일반적인 다목적댐은 홍수 발생 시 본댐으로 유입되는 부유쓰레기 및 잡목 등을 차단하기 위하여 댐 상류에 차단망을 설치하여 1차적으로 사전 방지하고, 홍수기 이후 선박으로 부유물을 수거하여 재활용, 소각 등으로 처리하는 시스템이다. 그러나 본 연구의 대상인 한탄강댐은 홍수조절용 댐으로서 수위 변화 폭이 매우 크고 정상 조건(비 홍수기)시는 대규모 홍수터가 드러나기 때문에 댐 유지관리 방법이 상이하며 한탄강 본류 구간은 하폭과 수심 등 하도의 불규칙성과 만곡부에서 유수의 흐름이 한쪽으로 쏠리는 편기 현상이 발생하는 등 복잡한 수리현상으로 인하여 부유쓰레기의 분포를 판단하기 어려운 지역이다. 따라서 본 연구에서는 부유쓰레기의 유동을 모의하기 위하여 HEC-HMS 모형과 $Vflo^{TM}$ 모형을 활용하여 본류와 지류의 빈도별 홍수량 분석을 실시하고, EFDC 3차원 동수역학 모형을 적용하여 홍수조절용지 내 부유쓰레기의 유입 경로 및 정체 구역을 분석하여 효과적인 쓰레기 처리 방안을 제시하고자 하였다. 분석 결과, 소규모 빈도 홍수(2년, 5년)의 경우 중 상류 지류의 부유쓰레기는 거의 유동하지 못하고 하도의 만곡의 영향을 받아 부분적으로 높은 밀도로 고착될 것으로 모의되며, 특히 본류와의 합류점 부근에 도달한 부유쓰레기는 유로 폭이 급확대되어 유속이 거의 없는 사수역 구간으로 변함에 따라 본류 배수위 영향으로 불규칙하게 맴돌다가 고착되는 것으로 모의되었다. 중규모 홍수(25년, 50년)의 경우, 상류부의 부유쓰레기의 분포는 소규모 홍수 시와 유사한 패턴을 보였으나 중류부에서 홍수파가 본류 하도를 월류하여 홍수터로 넓게 범람하는 지역에서는 소규모 홍수 시 본류 하도 양안에 분포하던 부유쓰레기가 홍수터 쪽으로 밀려가서 고착되는 경향을 보였다. 대규모 홍수(100년, 200년)의 경우, 댐과 인접한 분석 구간 하류부는 댐 배수위의 영향을 가장 크게 받으며 수심이 깊어 흐름이 가장 정체되는 구간으로 본류와 지류 모두 다량의 부유쓰레기가 분포할 것으로 분석되었다. 분석 구간 중류부는 홍수 규모가 증가함에 따라 넓은 홍수터로 침수범위가 급격하게 증가하며 이에 따라 부유쓰레기가 분포할 수 있는 면적이 크게 증가할 것으로 분석되었다. 또한 분석 구간 상류부는 협곡을 이루고 있어 홍수규모가 증가하더라도 침수범위와 부유쓰레기의 분포면적에 큰 변화가 없을 것으로 분석되었다. 본 연구 결과를 바탕으로 댐의 치수 문제가 발생하지 않도록 효과적으로 수거 처리 할 수 있는 부유쓰레기 적치장 및 차단 시설의 적정 설치 위치를 파악하였다.

• The Journal of the Korea Contents Association
• /
• v.22 no.6
• /
• pp.439-452
• /
• 2022

This study aimed to explore the relationships between random item usage and gaming disorder tendency. A total of 413 adults participated and demographic and psychosocial variables were collected using Cloninger's Temperament and Character Inventory, Cognitive Emotion Regulation Questionnaire, and Daily Hassles Scale for Korean Worker. The results are as follows. First, two-third of gamers used the random item games and women are more engaged than men in random item games. Second, there were significant differences of gaming disorder tendency, game use time, and game use money (both for general and random item) depending on the item use type. Third, predictors of gaming disorder tendency were found as game use money (general), game use time, maladaptive emotion regulation, stress, novelty seeking, and stress using multiple regression analysis. Proper intervention for gaming disorder tendency and the need of further research were discussed.

• Journal of Digital Convergence
• /
• v.17 no.8
• /
• pp.447-452
• /
• 2019

Modern people are investing a lot of time and economically in their appearance as a means of expressing their aesthetic desires. They have a lot of hair dyes that make up most of their appearance, but their hair damage is serious. Especially, they use hair dyes which are very popular among the hair cosmetics that make up most of their appearance, but their hair damage is serious. The purpose of this study is to investigate the hair tensile strength of hair with oxidative hair dye to induce styling while minimizing hair damage. The results showed that the Max. load, Max. stress, Max. elongation, break load, break stress, break elongation, maximum modulus and tangential modulus according to evaluation interval were significantly different between control and 8N-10N experimental groups. The maximum modulus and tangential modulus for the strain interval did not show tendency to increase or decrease constantly, although there was a difference between the control and experimental group. Therefore this study was conducted to investigate the correlation between hair loss and hair damage through the treatment of high grade oxidative hair dye, which is widely used in ield of industry. We want to provide application data.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.41 no.6
• /
• pp.675-686
• /
• 2021

This study investigated the ground displacement occurring in a slope below a waste-rock dumping site and estimated the likelihood of a disaster due to a landslide. To start with, photogrammetry was conducted by unmanned aerial vehicles (UAVs) to investigate the size and extent of the ground displacement. From April 2019 to July 2020, the average error rate of the five UAV surveys was 0.011-0.034 m, and an elevation change of 2.97 m occurred due to the movement of the soil layer. Only some areas of the slope showedelevation change, and this was believed to be due to thegroundwater generated during rainfall rather than the effect of the waste-rock load at the top. Sensitivity analysis for LS-RAPID simulation was performed, and the simulation results were compared and analyzed by applying a digital elevation model (DEM) and a digital surface model (DSM)as terrain data with 10 m, 5 m, and 4 m grids. When data with high spatial resolution were used, the extent of the sedimentation of landslide material tended to be excessively expanded in the DEM. In contrast, in the result of applying a DSM, which reflects the topography in detail, the diffusion range was not significantly affected even when the spatial resolution was changed, and the sedimentation behavior according to the river shape could be accurately expressed. As a result, it was concluded that applying a DSM rather than a DEM does not significantly expand the sedimentation range, and results that reflect the site situation well can be obtained.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.8 no.3
• /
• pp.576-592
• /
• 2007

We, in this study, tried to examine the influence of business environment, organization structure and information technology characteristics used on the performance of the information systems in Information and Communications Industries. The result shows that frequency of system usage and users' satisfaction are positively affected by the factors of business environment, organizational structure and information-technology. The user satisfaction of the system is affected by the frequency of system usage. Both financial performance and non-financial performance are affected by the frequency of the systems usage and user satisfaction of the system. With path analysis, we verified the overall model goodness-of-fit verified for the research model. The result shows that organization structureand technological factors are positively related to the frequency of usage and user satisfaction of the system, while the environmental factors are not. The frequency of system usage is not linked to both financial and non-financial performance. The user satisfaction of the system does not affected to the financial performance. In conclusion, the usage frequency and user satisfaction of the system are the moderating variables affecting business performances. These two variables are affected by the environment, organization structure and information technology. The Path analysis also supports the relationships among these variables.