• Nuclear Engineering and Technology
• /
• v.50 no.2
• /
• pp.280-291
• /
• 2018

In the framework of OECD/NEA Working Group on Fuel Safety, a RIA fuel-rod-code Benchmark Phase I was organized in 2010-2013. It consisted of four experiments on highly irradiated fuel rodlets tested under different experimental conditions. This benchmark revealed the need to better understand the basic models incorporated in each code for realistic simulation of the complicated integral RIA tests with high burnup fuel rods. A second phase of the benchmark (Phase II) was thus launched early in 2014, which has been organized in two complementary activities: (1) comparison of the results of different simulations on simplified cases in order to provide additional bases for understanding the differences in modelling of the concerned phenomena; (2) assessment of the uncertainty of the results. The present paper provides a summary and conclusions of the second activity of the Benchmark Phase II, which is based on the input uncertainty propagation methodology. The main conclusion is that uncertainties cannot fully explain the difference between the code predictions. Finally, based on the RIA benchmark Phase-I and Phase-II conclusions, some recommendations are made.

• Journal of Plant Biotechnology
• /
• v.5 no.2
• /
• pp.69-77
• /
• 2003

The ornamental industry encompasses cut flower, pot plant, turfgrass and nursery stock production and is an important part of the agricultural sector. As internationally traded commodities, cut flowers and plants are an integral part of the economy of a number of developing countries in South America, the Caribbean and Africa. Genetic modification (GM) is a tool with great potential to the ornamental horticulture industry. The rapid progress in our knowledge of plant molecular biology can accelerate the breeding ornamental plants using recombinant DNA technology techniques. Not only is there the possibility of creating new, novel products the driver of the industry but also the potential to develop varieties requiring less chemical and energy inputs. As an important non-food agricultural sector the use of genetically modified (GM) ornamental crops may also be ideal for the intensive farming necessary to generate pharmaceuticals and other useful products in GM plants. To date, there are only a few ornamental GM products in development and only one, a carnation genetically modified for flower colour, in the marketplace. International Flower Developments, a joint venture between Florigene Ltd. in Australia and Suntory Ltd. of Japan, developed the GM carnations. These flowers are currently on sale in USA, Japan and Australia. The research, development and commercialization of these products are summarized. The long term prospects for ornamental GM products, like food crops, will be determined by the regulatory environment, and the acceptance of GM products in the marketplace. These critical factors will be analysed in the context of the current legislative environment, and likely public and industry opinion towards ornamental genetically modified organisms (GMO's).

• Geomechanics and Engineering
• /
• v.13 no.3
• /
• pp.385-410
• /
• 2017

This work presents a simple and refined nth-order shear deformation theory for mechanical and thermal buckling behaviors of functionally graded (FG) plates resting on elastic foundation. The proposed refined nth-order shear deformation theory has a new displacement field which includes undetermined integral terms and contains only four unknowns. Governing equations are obtained from the principle of minimum total potential energy. A Navier type analytical solution methodology is also presented for simply supported FG plates resting on elastic foundation which predicts accurate solution. The accuracy of the present model is checked by comparing the computed results with those obtained by classical plate theory (CPT), first-order shear deformation theory (FSDT) and higher-order shear deformation theory (HSDT). Moreover, results demonstrate that the proposed theory can achieve the same accuracy of the existing HSDTs which have more number of variables.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.24 no.3
• /
• pp.139-146
• /
• 2019

As the number of electric vehicles (EVs) in Jejudo Island increases, the secondary use of EV batteries is becoming increasingly mandatory not only in reducing greenhouse gas emissions but also in promoting resource conservation. For the secondary use of EV batteries, their capacity and performance at the end of automotive service should be evaluated properly. In this study, the battery state information from the on-board diagnostics or OBD2 port was acquired in real time while driving three distinct routes in Jejudo Island, and then the battery operating characteristics were assessed with the driving routes. The route with higher altitude led to higher current output, i.e., higher C-rate, which would reportedly deteriorate state of health (SOH) faster. In addition, the SOH obtained from the battery management system (BMS) of a 2017 Kia Soul EV with a mileage of 55,000 km was 100.2%, which was unexpectedly high. This finding was confirmed by the SOH estimation based on the ratio of the current integral to the change in state of charge. The SOH larger than 100% can be attributed to the rated capacity that was lower than the nominal capacity in EV application. Therefore, considering the driving environment and understanding the SOH estimation process will be beneficial and necessary in evaluating the capacity and performance of retired batteries for post-vehicle applications.

• Journal of Navigation and Port Research
• /
• v.43 no.5
• /
• pp.296-301
• /
• 2019

The Electronic Chart Display and Information System (ECDIS) is an integral component of ship navigation equipment, that enables mariners to view Electronic Navigational Charts (ENC). Recently, it has become possible to transport freight and energy resources via the Northern Sea Routes (NSR) as global warming has been accelerating. However, ice can impact all types of ships and the potential danger that ice poses is significant. Until now, ice, consistently proven to be one of the most dangerous threats impacting navigation in ice-covered regions, has its detailed standard in the specification of the International Hydrographic Organization (IHO) for ECDIS. The investigations described in this paper were conducted to assess the advantages and problems of the display of ice objects on ECDIS. The experiments were conducted by using the Geographic Information System (GIS) to perform ice objects with their corresponding colors and symbols. Implementation of the standardized appearance of ice objects can enable mariners to access the ice condition of seas in a short time before navigating a safe passage through potentially treacherous waters. However, remain issues that must be overcome for data on ice to be fully compatible with an ECDIS system.

• Smart Structures and Systems
• /
• v.29 no.4
• /
• pp.617-624
• /
• 2022

A new intelligent adaptive control scheme was proposed that combines the control based on interference observer and fuzzy adaptive s-curve for flight path tracking control of unmanned aerial vehicle (UAV). The most important contribution is that the control configurations don't need to know the uncertainty limit of the vehicle and the influence of interference is removed. The proposed control law is an integration of fuzzy control estimator and adaptive proportional integral (PI) compensator with input. The rated feedback drive specifies the desired dynamic properties of the closed control loop based on the known properties of the preferred acceleration vector. At the same time, the adaptive PI control compensate for the unknown of perturbation. Additional terms such as s-surface control can ensure rapid convergence due to the non-linear representation on the surface and also improve the stability. In addition, the observer improves the robustness of the adaptive fuzzy system. It has been proven that the stability of the regulatory system can be ensured according to linear matrix equality based Lyapunov's theory. In summary, the numerical simulation results show the efficiency and the feasibility by the use of the robust control methodology.

• Structural Engineering and Mechanics
• /
• v.81 no.5
• /
• pp.633-645
• /
• 2022

The active tuned mass damper (ATMD) is an efficient and reliable structural control system for mitigating the dynamic response of structures. The inertial force that an ATMD exerts on a structure to attenuate its otherwise large kinetic energy and undesirable vibrations and displacements is proportional to its excursion. Achieving a balance between the inertial force and excursion requires a control law or feedback mechanism. This study presents a technique for the optimum design of a sliding mode controller (SMC) as the control law for ATMD-equipped structures subjected to earthquakes. The technique includes optimizing an SMC under an artificial earthquake followed by testing its performance under real earthquakes. The SMC of a real 11-story shear building is optimized to demonstrate the technique, and its performance in mitigating the displacements of the building under benchmark near- and far-fault earthquakes is compared against that of a few other techniques (proportional-integral-derivative [PID], linear-quadratic regulator [LQR], and fuzzy logic control [FLC]). Results indicate that the optimum SMC outperforms PID and LQR and exhibits performance comparable to that of FLC in reducing displacements.

• Nuclear Engineering and Technology
• /
• v.54 no.10
• /
• pp.3695-3702
• /
• 2022

South Korea, a country that built a world-class nuclear power infrastructure, shifted to a nuclear phaseout during the previous government's reign. This shift was pursued as part of a larger task of electricity mix reform, and one of the integral motives for such reform is addressing greenhouse gas (GHG) and fine dust problems. Thus, verifying the relationships between the public's concerns about GHG/fine dust and their acceptance of nuclear power generation is essential for designing public communication strategies to revive nuclear power under the ongoing environmental regime. Our analysis using a nationwide survey sample of South Korea (N = 1009, through proportionated quota sampling method) showed that the more people are concerned about GHG and fine dust, the less they accept nuclear power. These relationships held even after controlling for the effect of a third variable-energy-related environmentalism. This finding means that despite past communication efforts positioning nuclear power as a generation source that can mitigate GHG/fine dust emissions and the widely accepted scientific evidence that supports such positioning, nuclear power in Korea is in jeopardy. Our finding provides implications for public communications and fundamental knowledge for research on the determinants of nuclear power acceptance.

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2003.04a
• /
• pp.39-48
• /
• 2003

The ornamental industry encompasses cut flower, pot plant, turfgrass and nursery stock production and is an important part of the agricultural sector. As internationally traded commodities, cut flowers and plants are an integral part of the economy of a number of developing countries in South America, the Caribbean and Africa. Genetic modification (GM) is a tool with great potential to the ornamental horticulture industry. The rapid progress in our knowledge of plant molecular biology can accelerate the breeding ornamental plants using recombinant DNA technology techniques. Not only is there the possibility of creating new, novel products the driver of the industry but also the potential to develop varieties requiring less chemical and energy inputs. As an important non-food agricultural sector the use of genetically modified (GM) ornamental crops may also be ideal for the intensive farming necessary to generate pharmaceuticals and other useful products in GM plants. To date, there are only a few ornamental GM products in development and only one, a carnation genetically modified for flower colour, in the marketplace. International Flower Developments, a joint venture between Florigene Ltd. in Australia and Suntory Ltd.of Japan, developed the GM carnations. These flowers are currently on sale in USA, Japan and Australia. The research, development and commercialisation of these products are summarised. The long term prospects for ornamental GM products, like food crops, will be determined by the regulatory environment, and the acceptance of GM products in the marketplace. These critical factors will be analysed in the context of the current legislative environment, and likely public and industry opinion towards ornamental genetically modified organisms (GMO's).

• Nuclear Engineering and Technology
• /
• v.56 no.6
• /
• pp.2099-2112
• /
• 2024

This study examined the effects of CRUD on reflood heat transfer behaviors of nuclear fuel rods during a loss-of-coolant-accident (LOCA) in a pressurized water reactor using a best-estimate thermal-hydraulic analysis code. Changes in thermal properties and boiling heat transfer characteristics of the CRUD layer were extensively reviewed, and a set of correction factors to reflect the changes was implemented into the code. A heat structure layer reflecting the effects of CRUDs on the properties was added to the outer surface of the fuel cladding. Numerical simulations were conducted to examine the effects of CRUDs on reflood cooling of overheated fuel rods for representative separate and integral effect tests, FLECHT-SEASET and LOFT. In LOFT analysis, the average cladding temperature was increased due to the low thermal conductivity of CRUD during steady-state operation; however, in both analyses, the peak cladding temperature decreased, and the quenching time was reduced. Obtained results revealed that when the porous CRUD layer is deposited on the fuel cladding, two opposite effects appear. Low thermal conductivity of the CRUD layer always increases fuel temperature during normal operation; however, its hydrophilic porous structures may contribute to accelerated reflood cooling of fuel rods during a LOCA.