• Tunnel and Underground Space
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• v.8 no.3
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• pp.194-199
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• 1998

This research was aimed to figure out the trend of dust diffusion at open pit limestone mine for assessing the environmental impacts on the high voltage power transmission line. It is rather easy to assess the dust generation and size distribution of limestone dust at the blasting site, but it is very hard to assess the expected area of dust diffusion and amount of dust fall by the distances from the dust source. In this research, a 3-dimensional fluid dynamic simulation software (3D-Flow) was used for analysing the above mentioned matters to assess the impacts to the insulators on the transmission tower by the blasting dust. It was verfied that the 3D-Flow is reliable tool for simulating dust movement, and the limestone dust is not much hazardous to the power transmission line.

• Explosives and Blasting
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• v.19 no.2
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• pp.5-18
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• 2001

채석, 광물채광 등의 발파에서 생성된 파쇄 암석편들에 대한 정확한 파쇄도의 측정은 발파효율성 및 경제성을 평가하기 위한 수단으로 사용될 수 있다. 발파현장에서 파쇄도의 측정은 파쇄암석의 크기를 대상으로 이루어지며, 이러한 측정의 궁극적인 목표는 파쇄도에 대한 정확한 측정과 분석을 통하여 발파를 최적화시킴으로써 과파쇄에 의한 화약의 낭비, 과대한 암괴로 인한 운반경비의 증가, 분할을 위한 2차 발파나 추가파쇄를 위한 경비증가 등을 줄일 수 있다. 또한 선광 및 파쇄장비들의 과대한 마모방지와 품질의 균질성 확보를 위한 모니터링의 수단으로 사용될 수도 있다. 최근 파쇄도측정에 많이 사용되고 있는 기술중의 하나가 영상처리 시스템으로, 본 논문에서는 촬영조건 및 분석대상물 등의 변화에 따른 이 영상처리기법의 문제에 대한 언급보다는 영상처리기법에 대한 이해를 돕기 위해 이 기법에 대한 설명과 상용 소프트웨어를 이용한 모델시험 및 채석현장에서 실시된 발파후의 파쇄암석들에 대한 파쇄도 분석에서의 문제점들에 대하여 언급하고자 한다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.4
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• pp.323-337
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• 1999

Seafloor morphology and manganese nodule occurrence were studied in the Korea Deep-sea Environmental Study (KODES) area, northeast equatorial Pacific, to understand their relationship. Study area is composed of three elongated valleys and hills with about 100~200 m height along NNE-SSW direction. Valley region is generally flat. However, hill region is very rugged with big cliffs of about 100m height and small depressions of several tens of meters depth. Tectonic movement along the Clarion-Clipperton fracture zone, consequent formation of elongated abyssal hills and Valleys, erosion of siliceous bottom sediments by bottom currents, and dissolution of carbonate sediments on the abyssal hills below CCD result in the rugged morphology. Manganese nodule occurrence is closely related to the morphology of the study area; mostly rounded-shaped manganese nodules with about 5 cm diameter are abundant on the flat valley region, whereas irregular shaped nodules (or manganese crust) with less than 5 cm to about 1 m diameter occur on the hill. These results supports the previous reports that nodule abundance, composition, and morphology are variable both on regional and local small scales on the seafloor even within some abundant nodule provinces depending on oceanographic characteristics such as bathymetric features, surface sediment type, sediment thickness, and so on. We suggest that such oceanographic characteristics affect interrelatedly on the formation of manganese nodules, and tectonic movement of the Pacific plate ultimately constrain the nodule occurrence. A potential mining place in the KODES area seems to be the valley region, which is elongated to the NNW-SSE direction with 3-4 km width.

• Tunnel and Underground Space
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• v.21 no.1
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• pp.1-10
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• 2011

In these days, the development of optical fiber sensor technology is so remarkable that it can measure various physical and chemical quantities ranging from a few millimeters to over several kilometers. In addition, it is attempted to assess the structural integrity of the state of the advanced technologies and existing structures such as ships, aircrafts, and bridges. This paper introduced the case histories of the measuring technology of optical fiber applied on structures such as roads and tunnels. The case history using OTDR (Optical Time Domain Reflectometery) was also introduced in this paper. Measurement of the pre-convergence of a tunnel is essential to assess the safety of a tunnel and understand the geological conditions ahead of an advancing tunnel. Therefore, the pre-convergence measuring technology using OTDR is expected to substitute conventional measuring techniques.

• Economic and Environmental Geology
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• v.46 no.6
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• pp.569-580
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• 2013

Co-rich ferromanganese crusts (Fe-Mn crusts) distributed on the seamounts in the western Pacific are potential economic resources for cobalt, nickel, platinum, and other rare metals in the future. Regulations for prospecting and exploration of Fe-Mn crusts in the Area, which enables the process to obtain an exclusive exploration right for blocks of the fixed size, were enacted recently by the International Seabed Authority, which led to public attention on its potential for commercial development. Evaluation and selection of a mining site can be established based on abundance and grade of Fe-Mn crusts in the site as well as topography that should be smooth enough for mining efficiency. Therefore, acquisition of shipboard echo-sounding and acoustic backscatter data are prerequisite to select potential mine sites in addition to visual and sampling operations. Acoustic backscatter data can be used to locate crust-covered areas in a regional scale with the understanding of acoustic properties of crust through its correlation with visual and sampling data. KIOST had collected the topographic and geologic data to assess the resources potential for Fe-Mn crusts in the west Pacific region from 1994 to 2001. However, they could not obtain acoustic backscatter data that is crucial for the selection of prospective mining sites. Therefore, additional exploration surveys are required to carry out side scan sonar mapping combined with seafloor observation and sampling to decide the blocks for application of an exclusive exploration right.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.11
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• pp.1305-1310
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• 2012

The performance of a system can be affected by the variance of noise factors, which arise owing to uncertainties of the material properties and environmental factors acting on the system. For robust design optimization of the system performance, it is necessary to minimize the effect of the variance of the noise factors that are impossible to control. However, present robust design techniques consider the variation of design factors, and not the noise factors, as being important. Furthermore, it is necessary to assume a normal distribution; however, a normal distribution is often not suitable to estimate the variations. In this study, a robust design technique is proposed to consider the variation of noise factors that are estimated as non-normal distributions in a real experiment. As an example of an engineering problem, a deep-sea manganese nodule miner tracked vehicle is used to demonstrate the feasibility of the proposed method.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.3
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• pp.142-148
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• 1998

Environmental baseline information is necessary in order to assess the potential environmental impact of future manganese-nodule mining on the deep-seabed ecosystem. Total ATP (T-ATP), dissolved ATP (D-ATP) and particulate ATP (P-ATP) were measured to estimate total microbial biomass and to elucidate their vertical distribution patterns in the seabed of KODOS (Korea Deep Ocean Study) area, northeast equatorial Pacific Ocean. Within the upper 6 cm depth of sediment, the concentrations of T-ATP, D-ATP and P-ATP ranged from 4.4 to 40.6, from 0.6 to 16.1, and from 3.0 to 29.2 ng/g dry sediment, respectively. Approximately 84% of T-ATP, 81% of D-ATP, and 74% of P-ATP were present within the topmost 2 cm depth of sediment, and the distributions of ATP were well correlated with water content in the sediment. These results indicate that the distribution of total microbial biomass was largely determined by the supply of organic matter from surface water column. Fine-scale vertical variations of ATP were detected within 1-cm thick veneer of the sediment samples collected by multiple corer, while no apparent vertical changes were observed in the box-cored samples. It is evident that the box-core samples were disturbed extensively during sampling, which suggests that the multiple corer is a more appropriate sampling gear for measuring fine-scale vertical distribution pattern of ATP within thin sediment veneer. Overall results suggest that the concentrations of ATP, given their clear changes in vertical distribution pattern within 6 cm depth of sediment, are a suitable environmental baseline parameter in evaluating the variations of benthic microbial biomass that are likely to be caused by deep-seabed mining operation.

• KIEAE Journal
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• v.12 no.5
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• pp.77-84
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• 2012

Daylighting is the controlled admission of natural light into a space, reducing electric lighting and saving energy. By providing a direct link to the dynamic and perpetually evolving patterns of outdoor illumination, daylighting helps create a visually stimulating and comfort environment for building occupants, while reducing energy costs. Especially, however, glare is the most important factor in daylighting, which is issued by incoming direct sunlight into windows. This study analyzed the discomfort glare on a daylighting window by using Image processing methodology and found a solution to problems with glare source of occupants. There are several ways to evaluate discomfort glare such as UGR (Unified Glare Rating) of CIE, DGI (Daylight Glare Index, Hopkinson, 1972) and VCP (Visual Comfort Probability) of IES. These are used to apply to the relatively little artificial light source and they cannot cover discomfort glare from a real daylighting window. In this regarding, this paper aimed to calculate DGI index of the real daylighting window in a experimental space by using image processing methodology. The variables and outcomes are luminance distribution of non-shading window, effect of venetian blind installed on the window and locations related to position index of DGI.

• Mineral and Industry
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• v.21 no.1
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• pp.56-66
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• 2008

이 동향자료는 Geoscience Australia에서 2001년 발간한 "Geoscience Australia Mineral Resources Report No.1"과 역시 동 기관에서 2007년 발행한 "Australia's Identified Mineral Resources 2007" 중 일부 내용을 발췌하여 정리 한 것으로서 요약하면 다음과 같다. OECD/NEA와 IAEA(2000)는 세계적으로 분포하는 우라늄 광상유형을 지질학적인 형성환경에 따라 15개 유형으로 분류하였으며 호주에서는 각력복합형, 부정합형, 사암형, 지표형, 변성교대형, 변성형, 화산형, 관입형 및 맥상형이 보고되어 있다. 유형별 자원량은 각력복합형, 부정합형 및 사암형 3개 유형 광상이 약 93%를 차지하며, 각력복합형광상의 자원량이 63%에 달한다. 현재 개발되는 광상은 각력복합형의 올림픽댐 광산, 부정합형인 레인저 광산 및 사암형인 베벌리 광산이다. 호주는 세계 총 우라늄 자원량의 27%를 보유하고 있어 세계 1위를 차지한다. 올림픽댐광상이 항내채광을 하는 우라늄 광산으로서는 세계에서 가장 큰 광상으로서 US$80 이하에서 회수가능한 RAR(적정확정자원량)이 476,000톤이다. 이 자원량은 세계 총 자원량의 18%를 차지하며, 단일 광산으로서는 세계최대규모이다. 2006년 호주의 우라늄 총생산량은 $U_3O_8$ 8,943톤(7,584톤 U)이며 이는 세 광산에서 생산된 양으로서 캐나다에 이어 두 번째로 많은 양(세계 생산량의 19%)이다. 2006년 우라늄 수출량은 $U_3O_8$ 8,660톤(7,344톤 U)이며 수출가는 호주달러 5억2천9백만불에 달한다. 호주는 우라늄 수출국들과 "원자력협력협약"을 맺어 평화적 목적을 위해서만 공급한다는 단서를 달고 있으며 IAEA에 의해 관리/감독되고 있다. 최근 호주 정부는 지구과학연구소에 많은 예산을 투여하여 육상에너지안전대책을 발의하여 자원개발에 요구되는 탐사자료 확보에 주력하고 있다.

• KIEAE Journal
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• v.10 no.6
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• pp.97-103
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• 2010

Sky simulator is a effective daylighting design tool that can evaluate three dimensional performance of lighting. Especially, the dome type sky simulator offer reliable and reproducible daylighting performance with different standard sky models. Recently, K university has developed the dome type sky simulator(sky dome) with the diameter of 6.5m and the height of 3.7m. The sky dome consists of a group of 145 large steel panels with 72 halogen lamps which are arranged in a circular array. The luminance distribution of the sky dome can be calibrated by changing the angle and the brightness of the lamps respectively. To allow more reliable prediction and evaluation of daylighting through the sky dome, It is essential to validate the sky luminance distribution of the sky dome. This study consider the validation of the comparisons between the measured and the calculated luminance values for the CIE standard overcast sky. Also, the error rate between the measured and the calculated luminance values were compared to the previous studies. The results indicated that the K university sky dome can reproduce reliable CIE standard overcast sky with the average relative error rate of 4.4% and root-mean-square error(RMSE) of 5.4%.