• Journal of the Korea Institute of Information Security & Cryptology
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• v.29 no.1
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• pp.225-234
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• 2019

Bitcoin is a cryptocurrency with characteristics such as de-centralization and distributed ledger, and these features are maintained through a mining system called "proof of work". In the mining system, mining difficulty is adjusted to keep the block generation time constant. However, Bitcoin's current method to update mining difficulty does not reflect the future hash power, so the block generation time can not be kept constant and the error occurs between designed time and real time. This increases the inconsistency between block generation and real world and causes problems such as not meeting deadlines of transaction and exposing the vulnerability to coin-hopping attack. Previous studies to keep the block generation time constant still have the error. In this paper, we propose a machine-learning based method to reduce the error. By training with the previous hash power, we predict the future hash power and adjust the mining difficulty. Our experimental result shows that the error rate can be reduced by about 36% compared with the current method.

• Convergence Security Journal
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• v.22 no.1
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• pp.121-127
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• 2022

Recently, social issues related to cryptocurrency mining are continuously occurring at the same time as cryptocurrency prices are rapidly increasing. In particular, since cryptocurrency can be acquired through cryptographic operation, anyone with a computer can easily try mining, and as the asset value of major cryptocurrencies such as Bitcoin and Ethereum in creases, public interest is increasing. In addition, the number of cases where individuals who own high-spec computers mine cryptocurrencies in various places such as homes and businesses are increasing. Some miners are mining at companies or public places, not at home, due to the heat problem of computers that consume a lot of electrical energy, causing various problems in companies as well as personal moral problems. Therefore, this study studies the technology to obtain evidence for the traces of mining attempts using the Windows artifacts of the computers that mined cryptocurrency. Through this, it is expected that it can be used for internal audit to strengthen corporate security.

• Journal of Internet of Things and Convergence
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• v.10 no.2
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• pp.25-41
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• 2024

For the scenario of open pit mining, at present, manual periodic verification is mainly carried out in China with the help of video surveillance, which requires continuous investment in labor cost and has poor timeliness. In order to solve this difficult problem of early warning and monitoring, this paper researches a spatialized algorithmic model and designs an early warning system for open-pit mine transboundary mining, which is realized by calculating the coordinate information of the mining and extracting equipments and comparing it with the layer coordinates of the approval range of the mines in real time, so as to realize the determination of the transboundary mining behavior of the mines. By taking the Pingxiang area of Jiangxi Province as the research object, after the field experiment, it shows that the system runs stably and reliably, and verifies that the target tracking accuracy of the system is high, which can effectively improve the early warning capability of the open-pit mines' overstepping the boundary, improve the timeliness and accuracy of mine supervision, and reduce the supervision cost.

• Explosives and Blasting
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• v.30 no.2
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• pp.9-20
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• 2012

These days, mining industry prefers underground development for large mining because of exhaustive minning resources and large drafts and mining cavities thanks to extensive distribution of heavy excavation machines. In a mining design, to control collapse of cavities and secure stability, design of cavities and pillars are considered as very important. Therefore, this study obtained a prediction equation of blasting vibration through instrumentation for underground cavities. And we obtained theoretical shock vibration imposed on pillar through fragmentation analysis and measurement of flyrock distance. To examine the influence of pillar in underground mining blasting, we carried a finite element analysis and compared the result with prediction equation of blasting vibration, and shock vibration of flyrock when a impact was imposed on pillar and theoretical shock vibration.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.6
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• pp.693-700
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• 2017

The mines in our country are complex in geography and shape and because of its small scale, accurate surveying performance and 3D modeling are necessary for mine development and management and mining plans. However, due to the data acquisition and processing technology and economy, the existing methods are currently used. The structure, mining, and mining area of the mine are recorded and managed based on the 2D drawings. As a result, it is true that there is risk of accidents caused by problems of accuracy as well as waste of personnel and time. In recent years, research data on geology and geospatial information on mines have been integrated into a database in foreign countries, and they are used for mine management and mining planning. In this study, we tried to construct spatial information for mining management and mining plan using laser scanner. Through research, spatial information about the mine was effectively obtained and produced data modeled through data processing. The 3D model for mining mines is expected to be a valuable tool for establishing and operating a safe mining plan for mines.

• Journal of the Korean Geosynthetics Society
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• v.6 no.4
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• pp.7-13
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• 2007

When the structure such as roadway, railway are constructed on abandoned coal mine area, the countermeasure to prevent settlements is necessary. In this study, numerical analyses are performed to evaluate the effect of the various countermeasures. As a results, the method which is filling the coal mine is more effective than that of reinforcing the ground above the coal mine. The ground settlement decreases hyperbolically with increasing the filling ratio of the coal mine. Also, the relationship between the filling ratio and the settlement reduction ratio is discussed precisely.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.4
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• pp.399-403
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• 2013

Mining diggers have been substituted with the robots for the mining works in dangerous and narrow tunnel, and those demands are increased in nowadays. In this study, experimental research on the remote controlled robots to perform after the development of the robot. According to the test results, performances of the developed robot and its working devices have been modified several times. It has been considered that the robot keeps its optimum performance in states as follows; driving speed 1.0 km/h, crawl angle $10^{\circ}$, spiking cycle 500bpm and breaking power $30kg_fm$. And also it has been found that sufficient cooling for the robot's working parts is essential to extend those working periods longer than 3 hours steadily under rating condition.

• Journal of Korean Tunnelling and Underground Space Association
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• v.4 no.2
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• pp.135-141
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• 2002

This research has been conducted to investigate the influence of mined cavities on a tunnel to be constructed around a coal mine. The location and dimension of cavities were supposed by analysing synthetically geological structures and condition of coal beds as well as gangway map since there does not exist any map describing mined cavities. Detailed geological and geophygical survey have also been carried out for the purpose of understanding the geological structure and rock mass conditions. The two dimensional numerical analysis with FLAC has been performed on the geological sections reconstituted from the obtained information and the affects of mined cavities on the tunnel have been assessed.

• Proceedings of the Korean Society of Computer Information Conference
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• 2016.07a
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• pp.211-212
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• 2016

본 논문에서는 가상화폐이자 전자 거래의 신뢰성 있는 계약을 보장해 줄 수 있는 이더리움 (Ethereum)의 채굴 과정을 소개하고 향후 활용 방안을 제안한다. 이더리움의 거래 내역은 블록체인 (BlockChain)에 저장이 되며, 반영구적으로 삭제가 불가능하다. 이로써 전자상거래의 최대 단점인 사기 거래가 사전에 방지가 되고, 안전하고 깨끗한 거래가 성사될 수 있도록 하는 것이 목표이다. 이더리움 채굴을 위해서는 비디오카드의 GPU (Graphics Processing Unit)를 이용하였으며, 지갑 생성, 비디오카드 드라이버 설치, pool 서버 가입, 채굴 소프트웨어 설치 및 GPU 오버클럭킹 등의 과정을 수행하였다.

• Tunnel and Underground Space
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• v.25 no.5
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• pp.408-416
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• 2015

The collapse of the underground cavities and voids, which were made for developing mineral resources, can cause the subsidence of the ground surface in the residential areas. During the Japanese colonial era and the 1960's mining boom period, lots of mines had been developed indiscriminately in Korea. Due to complicated geological conditions and mining methods, many of dangerous underground mine cavities with steep slopes had been generated at the shallow surface. Due to such conditions, it is difficult to directly apply valid foreign reclamation practice for the cavities in Korea environments. It is necessary to develop the efficient ground stabilization technologies for the Korea underground mine conditions to solve abandoned mine reclamation properly. Therefore, MIRECO and Korea government have been carrying out practical researches and technical developments together with other academic researchers and reclamation business partners, and various practical solutions such as surveying and exploration methods, proper cavity filling materials and reinforcement methods have been developed with application in the mine field. In this article, up to date technologies and R&D trends in the field of mine subsidence prevention technology are broadly reviewed to establish the future direction of a research and development.