• STI Policy Review
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• v.4 no.1
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• pp.119-134
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• 2013

The Fukushima nuclear incident of 2011 served as an external shock that prompted Japan to reform its nuclear energy sector. The collusive relationship between the regulators within the Japanese government and the regulated power industry, as well as the lack of institutional independence of the regulatory agency, had derailed Japanese efforts to reform the sector for decades. The Fukushima crisis exposed these deeply-entrenched flaws in the system, causing public distrust and anger toward the government and the nuclear power sector. This paper discusses the institutional reform measures the Japanese government introduced in the wake of the Fukushima crisis to recover public confidence and revamp the sector to prevent future disasters. The paper also discusses the challenges the Japanese government faces on its road to a successful implementation of nuclear sector reforms.

• Journal of Ocean Engineering and Technology
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• v.30 no.6
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• pp.431-439
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• 2016

This paper reports a numerical method for determining the resistance and self-propulsion performance of an asymmetric pre-swirl stator used as an energy saving device by cancelling a propeller's rotational energy. The present asymmetric pre-swirl stator propulsion system consists of three blades at the port and one blade at the starboard, which can effectively recover the biased rotating flow. This paper provides the design concept for the present asymmetric stator, which produces more efficient results than a conventional propeller.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.4
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• pp.36-43
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• 2014

Recently, research has been conducted to develop the ORC (organic Rankine cycle), to recover waste heat from facilities such as industrial plants ultimately to create mechanical or electrical energy. The ORC system consists of a heat exchange, a condenser, a pump and a boiler. In this paper, 84 flow analyses were conducted with 21 cases and three variables, i.e., a number of large wings, a number of small wings, and RPMs. R245fa was used as a refrigerant. The flow cavitation phenomenon was investigated through a flow analysis, and a flow stream analysis was conducted.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.1990-1995
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• 2008

The thermochemical recycling of waste tires by pyrolysis is studied to recover the value added three by-products; a pyrolytic carbon black, a pyrolytic oil, and a non-condensable gas. The exhausted energy from pyrolysis of waste tires is converted for electricity power and process steam in cogeneration system. The characteristics of the pyrolysis recovered by-products as alternative energy resource are investigated with the design of a demonstration and a commercialization plant including cogeneration system, as called integrated pyrolysis cogeneration system.

• Nuclear Engineering and Technology
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• v.25 no.1
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• pp.1-7
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• 1993

This paper describes a prototype expert system to aid operation in rod consolidation process. The knowledgebase is composed of three database groups and 60 rules with production, and object oriented techniques that correlates database groups. The expert system is designed to track the transitions of nuclear materials through the operation areas of the rod consolidation process, to diagnose current status in any operating conditions, normal and off-normal, and to advise operators to properly recover off-normality. The expert system can give efficient management of nuclear material accountability and process operation in the rod consolidation.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.548-551
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• 2001

A zero-voltage transition (ZVT) PWM boost PFC converter using a transformer to recover the resonant energy into the input voltage is proposed. The proposed converter reduces turn-off switching loss of the auxiliary switch. The resonant current of the auxiliary circuit is optimally reduced by the feed-forwarded input voltage. Moreover, the resonant energy of the auxiliary circuit is recovered into the load and input voltages. In this paper, the modes of converter operation are explained and analyzed, design guidelines are given, and experimental results of 1.2kW, 200kHz prototype system are presented.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05a
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• pp.1-5
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• 2002

The sustain driver for AC plasma display panel should provide alternating high voltage pulses to ignite plasma and recover the energy discharged from the intrinsic capacitance between the scanning and sustaining electrodes inside the panel. In this paper, an efficient sustain circuit employing boost-up function is proposed to achieve a faster rise-time in order to be suitable to widely used the address display period separated (ADS) driving method. The proposed circuit improves the recovery efficiency, regardless of the variation of the panel capacitance. The principle of operation, features, and simulated results are illustrated and verified on a 7.5-inch diagonal panel at 200 [kHz] operating frequency based on experimental prototype.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.05a
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• pp.109-112
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• 2005

The electrical pulse separation of concrete samples for the recycling purpose has been investigated by the electrical disintegration method using the discharged high voltageimpulse. First, when the consumed energy increased in electrical crushing, fracture section area increased clearly. This result suggests that crushing energy was consumed efficiently. Secondly, when conventional crushing after electrical disintegration is compared with only conventional crushing, gravels are more stable after electrical crushing. Thus, electrical crushing makes it easy to recover gravels from wasted concrete. In the next year, more efficient recovery of gravel for wasted concrete by electrical disintegration will be investigated. Thus, actual wasted concrete crushing by electrical separation and combination of conventional crushing will be carried out.

• Journal of the Society of Naval Architects of Korea
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• v.41 no.3
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• pp.13-21
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• 2004

This paper deals with a theoretical and experimental method for the design of a biased asymmetric pre-swirl stator propulsion system which is an energy saving device by recovering a propeller rotational energy. In the case of slow-speed ships, the upward flow is generated along the afterbody hull form at the propeller plane. The generated upward flow cancels the rotating flow of the propeller at the starboard part while it increases at port part. The present biased asymmetric pre-swirl stator propulsion system consists of three blades at the port and one blade at the starboard which can recover the biased rotating flow effectively. This paper provides the design concept which gives more simple and a high degree of efficiency and the experimental results for the compound propulsion system.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.2
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• pp.121-128
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• 2002

A new high-efficient energy-recovery circuit is proposed to drive a plasma display panel (PDP) and compared with the conventional circuit. The proposed circuit uses only two inductors and no auxiliary circuit to recover the energy stored in the equivalent intrinsic capacitance of PDP. Therefore it features a simpler structure, less mass, lower cost of production, higher efficiency, and fewer power devices. The very stable and uniform light emitted from PDP proves the high quality of screen. It is suitable for wall-hanging color TVs. The proposed circuit, operating at 200kHz, is verified to be applicable on a 42-inch PDP by experimental results.