• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.3
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• pp.173-178
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• 2016

Many studies have been carried out on monitoring the target by cooperating a drone with remote sensors recently. This monitoring system uses static sensors to measure environmental data and drones to collect measured data. In geotechnical engineering, inspectors go around measuring the safety of construction site and it is impractical to compose a network among numerous sensors in terms of the cost efficiency. In this paper, we propose a data collection system based on interaction between a drone and a few sensors that are installed around the target structure for geotechnical projects. Through experimental results, we also verify the availability and the time and cost efficiency of the proposed system comparing with using inspectors.

• Solar Energy
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• v.18 no.3
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• pp.147-151
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• 1998

Several PV-diesel hybrid systems were built in isolated islands in Korea, where they are far from the inland to be supplied the electric power to a utility level from it. A lot of efforts has been concentrated to find a cost-effective electric supply system with higher reliability and minimum maintenance when compared with a diesel generator. For this purpose, an autonomous PV-diesel hybrid system with multi-channel remote monitoring system was investigated to supply electric power under minimum operating cost and maintenance in a small isolated island. In this report, the economic analysis was performed for comparison with photovoltaic system and diesel generator by computer simulation. And it was proven that a PV system is more cost-effective than an internal combustion engine for the remote island with less than 150 households. Especially, in the case of islands with less than 50 households, the initial construction cost of the PV system is comparable to and its operating cost is about 70% less than the diesel generator.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3D
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• pp.457-468
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• 2011

Recently, the non-vibration mass excavation method is used on sewage pipes and road construction sites in Jeju. However, a construction cost estimation based on the unit quantity does not provide a proper unit price. In this study, a comparison of the productivity of the standard quantity-per-unit costing method and the one of the work crew combination method was made based on the site monitoring of the non-vibration mass excavation method that is used in construction sites near Jeju. For this, data of 35 sites were collected: a regression equation was derived from the 30 data, and verification was carried out through the remaining 5 data. The analysis concluded that a day's workload is $16.43m^3$. In addition, a combination of the equipment considering the site conditions and the amount of labor, which varies with the number of work crew was obtained in order to estimate the construction cost of the work crew combination method. The construction cost was calculated based on the one-day workload ($16.43m^3$) derived from the regression analysis. The cost then was analyzed and compared with the standard quantity-per-unit costing method.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.127-132
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• 2008

As economic rapid growth, large structures are damaged by defects from design and construction process of the formation and environments. Therefore, safety diagnosis and monitoring skills are bringing importance into relief and legislate for safety diagnosis of large structures. However, the existing monitoring systems are difficult by using wire cable because of cost, error of date, location, revise. In this paper, wireless sensor network which are accelerator, temperature sensor system using ubiquitous had been field test on Sea-Hea Grand bridge. We compare accelerator, temperature sensor system with wire and wireless sensor network.

• Smart Structures and Systems
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• v.4 no.5
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• pp.517-530
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• 2008

This paper deals with civil infrastructures in general, sensor and smart structure technology, and smart steel structures in particular. Smart structures technology, an integrated engineering field comprising sensor technology, structural control, smart materials and structural health monitoring, could dramatically transform and revolutionize the design, construction and maintenance of civil engineering structures. The central core of this technology is sensor and sensor networks that provide the essential data input in real time for condition assessment and decision making. Sensors and robust monitoring algorithms that can reliably detect the occurrence, location, and severity of damages such as crack and corrosion in steel structures will lead to increased levels of safety for civil infrastructure, and may significantly cut maintenance or repair cost through early detection. The emphasis of this paper is on sensor technology with a potential use in steel structures.

• Nuclear Engineering and Technology
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• v.39 no.6
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• pp.691-696
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• 2007

Nuclear energy programs around the world increasingly find themselves at the nexus of potentially conflicting demands from both domestic and international stakeholders. On one side, the rapid growth in demand for electricity coupled with the goal of reducing carbon emissions calls for a significant expansion of nuclear energy. On the other, stakeholders are seeking ever greater safety, environmental, security, and nonproliferation assurances before consenting to the construction of new nuclear energy facilities. Satisfying the demand for clean energy supplies will require nuclear energy operators to find new and innovative ways to build confidence among stakeholders. This paper discusses two related concepts which can contribute to meeting the needs of key stakeholders in cost effective and efficient ways. Structured processes and tools for assessing stakeholder needs can build trust and confidence while facilitating the "designing-in" of information collection systems for new facilities to achieve maximum efficiency and effectiveness. Integrated approaches to monitoring facilities and managing the resulting data can provide stakeholders with continued confidence while offering operators additional facility and process information to improve performance.

• Ecology and Resilient Infrastructure
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• v.6 no.4
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• pp.277-286
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• 2019

The construction industry is known to be one of the representative industries that generate fine dust. Therefore, reducing the amount of fine dust generated in construction sites is very important for the overall fine dust management. Based on this, this study proposed the fine dust measurement and removal technology combined with advanced technologies such as autonomous mobile vehicle IoT and DFS. The qualitative, quantitative and risk elimination effects that can be expected when applying the proposed technique are analyzed. The proposed technique will be validated through system development and field application and evaluated specific economics through cost analysis.

• Corrosion Science and Technology
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• v.16 no.6
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• pp.294-297
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• 2017

For the longer service life of steel pile, cathodic protection is selected sometimes at corrosive environment. The cathodic protection design improvement was investigated in this study. The current demand for cathodic protection was calculated from the potentiostatic current monitoring of the steel specimen in the deaerated soil samples. In this study, the current distribution was studied using the Boundary Element Method (BEM) and the Finite Element Method (FEM) numerical analysis methods. The optimum layout of the anode was developed and confirmed by numerical analysis. Under the conventional design of the anode, the length of the anode hole is same as the pile length. We found that, at the bottom end of the pile, the current density is too high. When the anode hole length was 80% of the pile length, the current consumption at the end was reduced. The construction cost of anode hole drilling was decreased about 20%, as compared to the conventional design. Furthermore, the life of the anode materials could be extended by reducing the current consumption at the end section. Using this approach, the construction cost was reduced significantly without any under-protection area on the steel piles.

• Journal of Construction Engineering and Project Management
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• v.4 no.4
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• pp.47-59
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• 2014

Client organization inadequate project planning before awarding the contract and insufficient monitoring and control system among the parties involved create severe problems. Ultimately, large-scale projects go beyond the expected cost and time control limits. This paper discusses the major issues involved with a large-scale Hydropower Project in Pakistan Public Sector environment. The latest approved Baseline Plan of project was reviewed and analyzed using Variance Analysis and Trend Analysis techniques in Primavera project management software to assess the efforts made of the parties involved. It was found that Project is 202% Cost overrun and 25% time delays from original contract award. After analysis of baseline plan and quantification of various variance issues in impacted activities, the questionnaire survey was conducted to identify the impact of causative factors. There were almost 17 most significant causative factors identified among 60 identified factors and responsibilities are assigned accordingly. At the end recommendations are made for strategic decisions as lessons learned during project evaluation.

• The Journal of Engineering Geology
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• v.33 no.1
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• pp.27-37
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• 2023

Assessing landcreep requires long-term monitoring, because cracks and steps develop over long periods. However, long-term monitoring using wire extensometers and inclinometers is inefficient in terms of cost and management. Therefore, this study selected an area with active landcreep and evaluated the feasibility of monitoring it using imagesing from terrestrial LiDAR and drones. The results were compared with minute-by-minute data measured in the field using a wire extensometer. The comparison identified subtle differences in the accuracy of the two sets of results, but monitoring using terrestrial LiDAR and drones did generate values similar to the wire extensometer. This demonstrates the potential of basic monitoring using terrestrial LiDAR and drones, although minute-byminute field measurements are required for analyzing and predicting landcreep. In the future, precise monitoring using images will be feasible after verifying image analysis at various levels and accumulating data considering climate and accuracy.