• Proceedings of the KSR Conference
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• 2003.05a
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• pp.505-510
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• 2003

The interests about railway safety have been highly increased. Early railway safety was widely studied in Europe and Japan, and safety standards were established in 1990s. EN 50126 of CENELEC, Railway applications - Specification and demonstration of RAMS, became IEC 62278 in 2002. This standard provides Railway Authorities and railway support industry with a process which will enable the implementation of a consistent approach to the management of RAMS. IEC 62278 will be often referred to in the field of railway system. This paper examined the application of railway RAMS on basis of IEC 62278.

• Proceedings of the KSR Conference
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• 1999.11a
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• pp.447-454
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• 1999

In this paper, a technique for the shape design and analysis of rail fastener is presented. KRRI's own 3 type fasteners are developed after due consideration for tile aspects of installation, maintenance, and cost of fastener. Numerical by using commercial FEM program COSMOS/Works are carried out to determine the optimal shape of fastener clip. Front tile manufactured models and numerical results, the developed fasteners show tile possibility to be commercialized. But in order to have their competitiveness on the markets, further studies are required for the demonstration of performance through laboratory and field tests

• Journal of Drive and Control
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• v.19 no.1
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• pp.81-85
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• 2022

• Journal of Energy Engineering
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• v.24 no.1
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• pp.51-57
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• 2015

The purpose of this study is to verify the performance of a static mixer for mixing of biogas and town gas by numerical analysis and demonstration test. The reason for designing a static mixer is that there is a need to mix town gas with biogas when there is less production of biogas in biogas sites. Non-uniformity in the outlet section was calculated for investigating the performance of a static mixer. Non-uniformity was based on the mole fraction of methane in a mixture of biogas and town gas. Low non-uniformity means that biogas and town gas are mixed well through this static mixer. Also, pressure drop at the outlet section of a static mixer was calculated. The pressure drop is less than 0.2% in this static mixer. This static mixer is suitable for applying to a 5MW bio-gas turbine through the demonstration test in the field.

• Journal of Korean Society of Water and Wastewater
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• v.35 no.1
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• pp.1-14
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• 2021

Eutrophication and algal blooms can lead to increase of taste and odor compounds and health problems by cyanobacterial toxins. To cope with these eco-social issues, Ministry of Environment in Korea has been reinforcing the effluent standards of wastewater treatment facilities. As a result, various advanced phosphorus removal processes have been adopted in each wastewater treatment plant nation-widely. However, a lot of existing advanced wastewater treatment processes have been facing the problems of expensive cost in operation and excessive sludge production caused by high dosage of coagulant. In this study, the sedimentation and dissolved air flotation (SeDAF) process integrated with sedimentation and flotation has been developed for enhanced phosphorus removal in wastewater treatment facilities. Design and operating parameters of the SeDAF process with the capacity of 100 ㎥/d were determined, and a demonstration plant has been installed and operated at I wastewater treatment facility (located in Gyeonggi-do) for the verification of field applicability. Several empirical evaluations for the SeDAF process were performed at demonstration-plant scale, and the results showed clearly that T-P and turbidity values of treated water were to satisfy the highest effluent standards below 0.2 mg/L and 2.0 NTU stably for all of operation cases.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.78-78
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• 2015

Metamaterials, artificially structured nanomaterials, have enabled unprecedented phenomena such as invisibility cloaking and negative refraction. Especially, hyperbolic metamaterials also known as indefinite metamaterials have unique dispersion relation where the principal components of its permittivity tensors are not all with the same signs and magnitudes. Such extraordinary dispersion relation results in hyperbolic dispersion relations which lead to a number of interesting phenomena, such as super-resolution effect which transfers evanescent waves to propagating waves at its interface with normal materials and, the propagation of electromagnetic waves with very large wavevectors comparing they are evanescent waves and thus decay quickly in natural materials. In this abstract, I will focus discussing our efforts in achieving the unique optical property overcoming diffraction limit to achieve several extraordinary metamaterials and metadevices demonstration. First, I will present super-resolution imaging device called "hyperlens", which is the first experimental demonstration of near- to far-field imaging at visible light with resolution beyond the diffraction limit in two lateral dimensions. Second, I will show another unique application of metamaterials for miniaturizing optical cavity, a key component to make lasers, into the nanoscale for the first time. It shows the cavity array which successfully captured light in 20nm dimension and show very high figure of merit experimentally. Last, I will discuss the future direction of the hyperbolic metamaterial and outlook for the practical applications. I believe our efforts in sub-wavelength metamaterials having such extraordinary optical properties will lead to further advanced nanophotonics and nanooptics research.

• Korean Journal of Organic Agriculture
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• v.26 no.2
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• pp.173-180
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• 2018

This study was conducted to investigate farmers' satisfaction in organic farming technologies developed by the Rural Development Administration (RDA). The survey targeted farmers who were eco-friendly or interested in eco-friendly agriculture. 70% of the target farmers were doing eco-friendly farming, and the satisfaction rate of the technology developed by the RDA was 3.85 points. The satisfaction of the farmers who participated in demonstration and demonstration of the farming field of the developed technology was 4.00 and the satisfaction level of organic farming instruction manual was 3.95. In addition, 38.4% of the surveyed areas were found to be pest control areas, and the impacts on the satisfaction of the organic cultivation related technology utilization and the satisfaction of the organic cultivation guide were analyzed. As a result, the RDA needs to develop and supply customized technology for aged small farmers.

• Journal of the Korean Solar Energy Society
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• v.36 no.2
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• pp.53-63
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• 2016

Building Integrated Photovoltaic (BIPV) is one of the best ways to generate electric power using the solar energy, which is clean and inexhaustible energy resources. The most of BIPV modules have the form of GtoG (Glass to Glass) photovoltaic in building applications. Degradation leading to failure in photovoltaic modules is very important factor in BIPV modules. This paper analyzed the performance of various BIPV modules through outdoor exposure tests. Performance of three BIPV modules(c-Si type, a-Si type and DSSC type) with three installation angles influenced by sun light, outdoor temperature, and wind velocity was monitored and analyzed. As a result, c-Si type BIPV module outperforms other BIPV modules(a-Si type). In terms of power efficiency of the module, the installed angle of $45^{\circ}$ is better than others(90 degree, 0 degree). In addition, more realistic data of various BIPV system performance could be available through the field test and integrated building test. In this study, relationship of the BIPV system is identified module's installation angle, power generation, architectural performance, etc.

• Journal of Mechanical Science and Technology
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• v.19 no.10
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• pp.1864-1874
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• 2005

This paper describes a wearable multi-modal user interface design and its implementation for a teleoperated field robot system. Recently some teleoperated field robots are employed for hazard environment applications (e.g. rescue, explosive ordnance disposal, security). To complete these missions in outdoor environment, the robot system must have appropriate functions, accuracy and reliability. However, the more functions it has, the more difficulties occur in operation of the functions. To cope up with this problem, an effective user interface should be developed. Furthermore, the user interface is needed to be wearable for portability and prompt action. This research starts at the question: how to teleoperate the complicated slave robot easily. The main challenge is to make a simple and intuitive user interface with a wearable shape and size. This research provides multi-modalities such as visual, auditory and haptic sense. It enables an operator to control every functions of a field robot more intuitively. As a result, an EOD (explosive ordnance disposal) demonstration is conducted to verify the validity of the proposed wearable multi-modal user interface.

• Environmental and Resource Economics Review
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• v.12 no.4
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• pp.611-635
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• 2003

This study deals with the "Dissemination Stage", the final step in the R&D process consisting of R&DDD($R&D^3$ : Research & Development, Demonstration, Dissemination). At the "Dissemination Stage", the newly configured technical design is compared with other alternatives to come up with the most desirable selection. The assessment conducted at this stage is not a simple procedure. It goes through the complex evaluation process in which various elements including economic effects and technical characteristics are considered. The reason for taking such a complex procedure is that the assessment, selection and application of the desirable technical alternative is critical for the company's competitive edge in every field of industrial sectors, thus influencing its survival and continuous growth. This study reviews the AHP method for assessing technical alternatives of the heat supply system design. And, to show the practical validity of the AHP method, it is applied to the evaluation of waste heat system alternatives in the field of energy supply system technology.