• KOREAN POULTRY JOURNAL
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• v.10 no.6 s.104
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• pp.49-49
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• 1978

• Journal of Korean Tunnelling and Underground Space Association
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• v.9 no.3
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• pp.263-273
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• 2007

When a tunnel or an underground structure is excavated in deep geological environments, the failure process is affected and eventually dominated by stress-induced fractures growing preferentially parallel to the excavation boundary. This fracturing is generally referred to as brittle failure by spatting and slabbing. Continuum models with traditional failure criteria such as Hoek-Brown or Mohr-Coulomb criteria have not been successful in prediction of the extent and depth of brittle failure. Instead cohesion weakening and frictional strengthening (CWFS) model is known to predict brittle failure well. In this study, CWFS model was applied to predict the brittle failure around a circular opening observed in physical model experiments. To obtain the input parameters for CWFS model, damage-controlled tests were carried out. The predicted depth and extent of brittle failure using CWFS model were compared to the results of the physical model experiment and numerical simulation using traditional model.

• Tunnel and Underground Space
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• v.16 no.6 s.65
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• pp.437-450
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• 2006

Failure around an underground opening is a function of in-situ stress magnitudes, intact rock strength and the distribution of fractures in the rock mass. At high in-situ stress, the failure process is affected and eventually dominated by stress-induced fractures preferentially growing parallel to the excavation boundary. This fracturing is often observed in brittle type of failure such as slabbing or spatting. Recent studies dies on the stress-induced damage of rock revealed its importance especially in a highly stressed regime. As the constructions of underground structures at deep depths increased, the cases of the brittle failure also increased and furthermore spalling was occurred in Korea at low depths. To improve the stability of the underground structures at highly stressed regime, the characteristics of brittle failure should be examined, but they have not yet been properly investigated. Therefore in this report the characteristics of brittle failure such as types, failure mechanism and modeling methods etc. were considered in all aspects, based on the previous researches.

• Tunnel and Underground Space
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• v.17 no.1 s.66
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• pp.32-42
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• 2007

Severe damage can occur around deposition holes due to complex interaction of thermo-hydro-mechanical (THM) loading during the long term operation of high level radioactive waste repository. Many candidate sites for repository are located in crystalline rock mass, therefore mechanism of damage follows the form of brittle fracture and failure. This paper briefly introduces major outcomes from 15 years international collaborative project, DECOVALEX, and presents major study results for current ongoing benchmark test study from DECOVALEX-THMC, to evaluate the effect of THM loading to rock mass in excavation damaged zone (EDZ) near deposition holes. Through benchmark test model by simplifying THM loading to boundary loading obtained numerical results are compared, and discrete fracture interaction after up to 1 million years operation is discussed.

• Tunnel and Underground Space
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• v.17 no.1 s.66
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• pp.26-31
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• 2007

The 11 nuclear power plants have been taking charge of more than 40% of the total electrical power development in Korea. In addition to the existing nuclear power plants at Gori, Wolsung, Youngkwang, etc., the 12 nuclear power plants are expected to be newly established until 2006. So, the 23 nuclear power plants will produce the electric power as much as more than 50% of the national gross production. However the nuclear power plants are inevitably generating the detrimental atomic wastes. Therefore the disposal techniques for the nuclear wastes should be ensured considering a very high safety factor. According to the basic researches in KAERI, the underground disposal repositories are reported to be most favorable for Korea. The KBS-3 disposal system has been strongly suggested by KAERI and this system has a deep tunnel with several disposal boreholes in tunnel floor. The nuclear wastes, which are sealed tightly in a canister, will be disposed in these boreholes. Considering the disposal tunnel in a great depth, the in-situ stress regimes will affect severely the tunnel stability. Consequently the effect of the in-situ stresses on the disposal tunnel and the role of the in-situ stresses in tunnel stability analysis are examined by the numerical studies.

• Agrochemical news magazine
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• v.20 no.1 s.148
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• pp.26-29
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• 1999

• The Korean Publising Journal, Monthly
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• s.307
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• pp.23-23
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• 2001

• Food Industry
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• s.15
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• pp.36-41
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• 1973

농약은 국민 식생활의 근본 및 보건위생 전반에까지 크게 위해를 초래하여 크게 말썽이 되고 있다. 이러한 위해현상은 거의 한계점에까지 임박하고 있어 세계각국은 안전대책마련에 크게 고심하고 있다.

• 식품문화 한맛한얼
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• v.1 no.4
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• pp.29-32
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• 2008

찬바람이 불기 시작하면 주부들의 마음은 한없이 바빠진다. 바로 김장철이 다가왔기 때문이다. 우리 어머님들은 김장철이 다가오면 품질 좋은 재료를 고르기 위한 동분서주가 시작되고 무엇보다도 고심하는 재료 중의 하나가 바로 고추이다.

• Electric Engineers Magazine
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• v.253 no.9
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• pp.34-38
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• 2003

전력시설물중 전동기설비가 차지하는 비중이 매우 높으며 생산과의 직접적인 관계가 있는 생산설비의 모터고장으로 인한 생산손실은 이루 말할 수 없이 크다. 어떻게 하면 모터의 고장을 좀더 줄일 수 있을까? 관련 저력기술들의 고심이 이만저만이 아닐 것이다.