• 전기의세계
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• v.46 no.7
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• pp.72-74
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• 1997

1887년 우리나라에서 처음 전기를 사용하기 시작한 이래 초기에는 모든 송배전 선로의 전선은 수입에 의존해야 했으며, 가공 송배전이 주축을 이루었던 시절이었으나, 현재에는 전기에너지의 전달 수단으로써 전선은 꾸준한 발전을 이룩하여 국내에서 소요되는 전선량의 대부분을 국내 생산으로 충족하고 있는 실정이다. 우리나라 전선의 국산화는 1955년 국내 최초의 전선업체인 대한전선(주)이 설립되면서부터 시작되었으며, 그 이후 자체 연구개발 및 해외로부터의 기술도입에 박차를 가하게되고, 이를 계기로 송배전 선로의 지중화 즉, 케이블화가 시작된 것이다. 국내에 최초로 수입된 지중배전선로가 운전을 개시한 1929년 이후 40여년 만인 1970년에 국내 최초의 국산 지중배전선로가 포설, 운전하기에 이르렀고, 이렇게 축적된 기술을 기반으로 하여 1971년 수입 포설된지 불과 7년 후인 1978년 국내최초로 국산 초고압케이블이 개발.시공.운전하기에 이르렀다. 이로써 케이블 국산화는 가일층 증가 일로에 있었으며, 현재는 산업의 동맥으로써 중요한 역할을 담당하고 있다.

• Journal of the Korea Institute of Military Science and Technology
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• v.8 no.1 s.20
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• pp.32-38
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• 2005

In this study, Experimental analysis on submarine cable tension was performed for the safe and efficient laying and recovery of a submarine cable. The tension analysis was done through the analyzed data using the cable dynamic theory and the measured data using the experiment. The analyzed cable tension was able to decide requirements for the purpose of laying and recovery of the submarine cable. As the result of tension analysis for a Submarine cable, it was shown a proper feasibility to determine the laying and recovery conditions of the submarine cable.

• 한국정보통신설비학회:학술대회논문집
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• 2005.08a
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• pp.206-209
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• 2005

공기압을 이용한 광케이블 다조포설장치는 비닐로 만들어진 내관을 이용하여 케이블 또는 견인선을 동시에 포설하므로써 작업시간을 줄일 수 있고, 관로의 공간을 최소화하여 한 관로내에 다수의 광케이블을 포설할 수 있는 기술이다. 이 기술은 지하 관로를 효율적으로 사용하여 선로구축비용을 절감하고, 지하 관로내 단차가 있을 경우에도 원활히 선통할 수 있는 장점이 있다. 또한 다조 포설시 발생할 수 있는 케이블간의 꼬임에 무관하며, 공기압을 이용하므로 광케이블에 인장력을 적게 인가하므로 광케이블의 특성변화를 최소화 할 수 있는 광케이블 포설 기술이다.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.663-664
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• 2007

지중송전선로 건설공사에 154kV 장조장 케이블 드럼개발 및 트레일러 일체형 Under Roller 방식을 이용한 포설장비를 개발하여 현장에 적용함으로써 신기술 신개발 공법 적용으로 인한 국제경쟁력 향상 뿐만 아니라 접속경간의 장조장 설계로 케이블 접속개소 감소로 인한 공사비절감과 공사기간 단축에 크게 기여하였다. 이와 동시에 공사를 위한 도로점용 단축으로 민원발생을 크게 감소시켰다. 현행 도로법 규제로 케이블의 운반중량이 제한되었던 케이블 표준 경간을 450m에서 최대 700m까지 가능하여 접속개소의 유연성이 확보되었을 뿐만 아니라 토목구조물(전력구,관로등)공사의 다양한 설계방법을 적용할 수 있게 되었다.

• 지반과기술
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• v.3 no.1
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• pp.67-75
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• 2006

• Journal of the Korean Geosynthetics Society
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• v.4 no.2
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• pp.29-38
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• 2005

It is essential to take consideration of long-term deformation characteristics of mechanically stabilized earth wall user sustained and repeated loads for design and construction, especially for use as part of permanent structures. This paper presents the long-term performance of a full-scale geogrid reinforced segmental retaining wall results based on the measured strains in geogrids for three years. The results indicate that the reinforcement tensile strains tend to continuously increase after wall completion with the increase being more pronounced in the reinforcement layers in the lower tier. It can be concluded that the long-term deformation should be taken in account for walls constructed as part of permanent structures for which wall deformation should be controlled.

• The KIPS Transactions:PartC
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• v.15C no.3
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• pp.205-212
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• 2008

In the environment with multiple heterogeneous wireless sensor networks with a single point of sensed data collection or a gateway (GW), relay points (RPs) may be required for the energy efficient delivery of sensed data from static or mobile sinks to the GW. The optimal placement of RPs becomes an even more difficult problem if static sinks are dynamically added or the trajectory of mobile sinks can not be known in advance. In order to resolve this problem, we propose a mechanism to deploy RPs in a grid pattern and to use the tree-based relaying network for reducing the cost of the RP and for reducing the control overhead incurred by the route setup from sinks to the GW. For the performance evaluation of our proposed mechanism, we have carried out a numerical analysis on a single route setup from a sink to the GW and, for more general performance evaluations, ns-2 based simulations have been carried out. According to the performance evaluation results, our tree-based relaying network mechanism outperforms that based on AODV in terms of the data delivery time, the network service time and the control overhead.

• Journal of the Korean Geotechnical Society
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• v.21 no.10
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• pp.49-60
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• 2005

This paper presents the results of an investigation on the effects of design variables on the behavior of geosynthetic-reinforced modular block walls in a tiered arrangement using the finite-element method of numerical analysis. A parametric study was performed by varying the offset distance between the tiers and reinforcement length of the lower and upper tier using verified finite-element model. The finite-element analysis provided relevant information on the mechanical behavior of the tier wall and interaction mechanism between the upper and lower tier, which was otherwise difficult to obtain from the limit-equilibrium analysis based current design approaches. Practical implications of the findings obtained from this study in the current design approaches are discussed in great detail.

• Journal of the Korean Geosynthetics Society
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• v.6 no.1
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• pp.1-7
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• 2007

In order to improve the bearing capacity of soft ground for the purpose of getting a trafficability of construction vehicles, the geosynthetics-sandmat system has often been used. Yamanouchi had proposed the equation of calculating the bearing capacity about this kind of bearing mechanism, which has a soft ground-geosynthetics-sandmat system. The bearing capacity equation by Yamanouchi has been widely using in our country. However this equation includes an important contradictory concept because if the contact width of vehicles is incresed to reduce the contact pressure, the bearing capacity is decresed on the contray according to this equation. In order to investigate this contradictory concept, the bearing capacity test has been performed on the soft model ground with geosynthetics-sandmat system. From the test results about various kinds of models, the principle that explain the contradictory concept has been found and on the basis of this principle the new bering capacity equation has been proposed by modifying Yamanouchi equation.

• Journal of the Korean GEO-environmental Society
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• v.6 no.1
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• pp.23-31
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• 2005

The "Silt Pond" is 180 hectares in size and contained ultra soft slurry-like soil varying between 3 to 20 meters in thickness. Reclamation works in the Silt Pond commenced in the mid of 1990s. A considerable amount of subsurface investigation inclusive of sampling, field vane and density logging tests were carried out prior to the reclamation of the Silt Pond. Since material in the Silt Pond is extremely soft, filling was done by spreading sand with high water content in thin and equal thickness lifts, allowing the stability of the slurry-like foundation. Despite the extreme care taken, failures occurred during the sand spreading phase. A large piece of high strength geotextile measuring $900m{\times}700m$ was placed to strengthen the slurry like soil foundation at locations where the ultra-soft soil was found to be exposed. Following the remedial works, the Silt Pond was again reclaimed by sand spreading up to +4.0m CD. The success of the reclamation was confirmed by marine CPT profiling.