• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.4125-4133
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• 2023

The transportation of spent nuclear fuel is an important process that involves road and sea transport from an interim storage facility to storage and final disposal sites. As spent nuclear fuel poses a significant risk, carefully evaluating its vibration and shock characteristics under normal transport conditions is essential. In this regard, full-scale multi-modal transport tests (MMTT) have been conducted domestically and internationally. In this paper, we discuss the process of developing a multi-body dynamics (MBD) model to analytically simulate conditions that cannot be considered in tests. The MBD model is based on the KORAD-21 transportation system was validated using the Korean MMTT results from 2020 to 2021. This paper summarizes the details of the development and verification of the MBD model for the KORAD-21 transportation system under normal transport test conditions. This approach can be applicable to various transportation scenarios and systems, and the results of this study will help to ensure that nuclear fuel transportation is conducted safely and effectively.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.4
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• pp.439-450
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• 2023

In this study, the impact load resulting from collision with the fuel rods of surrogate spent nuclear fuel (SNF) assemblies was measured during a rolling test based on an analysis of the data from surrogate SNF-loaded sea transportation tests. Unfortunately, during the sea transportation tests, excessive rolling motion occurred on the ship during the test, causing the assemblies to slip and collide with the canister. Hence, we designed and conducted a separate test to simulate rolling in sea transportation to determine whether such impact loads can occur under normal conditions of SNF transport, with the test conditions for the fuel assembly to slide within the basket experimentally determined. Rolling tests were conducted while varying the rolling angle and frequency to determine the angles and frequencies at which the assemblies experienced slippage. The test results show that slippage of SNF assemblies can occur at angles of approximately 14° or greater because of rolling motion, which can generate impact loads. However, this result exceeds the conditions under which a vessel can depart for coastal navigation, thus deviating from the normal conditions required for SNF transport. Consequently, it is not necessary to consider such loads when evaluating the integrity of SNFs under normal transportation conditions.

• Journal of Korean Society of Transportation
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• v.30 no.2
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• pp.117-126
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• 2012

The transportation sector accounts for 33% of the total $CO_2$ emissions. Effective control measures for reducing $CO_2$ emissions are urgently needed to address global warming. Objective and reliable methods to estimate $CO_2$ emissions are a prerequisite for the implementation of such effective control measures. However, existing models have not been successful. Even though the average-speed model is one of the most convenient and useful methods for estimating $CO_2$ emissions, it cannot distinguish between a variety of roads as well as traffic conditions in the model. The results of this study found that there may be significant discrepancies between emissions estimated by the current average-speed model and those measured in real driving conditions. This paper proposed the subdivision of emission factors in the average-speed model depending on both traffic and road conditions.

• Journal of Radiation Industry
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• v.17 no.4
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• pp.321-326
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• 2023

Radiopharmaceuticals that need to be transported in a low-temperature state must satisfy both radiation safety and proper temperature maintenance. However, an efficient transport system considering the characteristics of radiopharmaceuticals that require low temperature maintenance has not yet existed. In order to secure a transportation system for the safe and stable transportation of the radiopharmaceutical ¹³¹I mIBG, which requires transportation in cryogenic conditions, we have developed a transportation system that can maintain cryogenic conditions below -60℃ for 6 days while stably fixing the inner container. In addition, by applying a data logger that can simultaneously measure the temperature and the dose of radiation, safety and stability in the transportation process can be secured at the same time. The cryogenic transportation system for ¹³¹I mIBG will be applied to products currently being supplied, and we expect to dramatically improve the management of cold chain radioactive material transportation.

• Nuclear Engineering and Technology
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• v.56 no.2
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• pp.375-388
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• 2024

In this study, to evaluate the shock and vibration load characteristics of used fuel, a sea transportation test was conducted using simulated fuel assemblies under normal transport conditions. An overall test data analysis was performed based on the measured strain and acceleration data obtained from cruise, rotation, acceleration, braking, depth of water, and rolling tests. In addition, shock response spectrum and power spectral densities were obtained for each test case. Amplification and attenuation characteristics were investigated based on the load path. The load was amplified as it passed from the overpack to the simulated used fuel-assembly. As a result of the RMS trend analysis, the fuel-loading position of the transportation package affected the measured strain in the fuel rod, and the maximum strains were obtained at the spans with large spacing. However, even these maximum strains were very small compared to the fatigue strength and the cladding yield strength. Moreover, the fuel rods located on the side exhibited a larger strain value than those at the center.

• Transportation Technology and Policy
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• v.13 no.1
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• pp.23-30
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• 2016

• Journal of Korean Society of Transportation
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• v.3 no.1
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• pp.76-85
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• 1985

The significant role of transportation system for economic development process has been recognized, but the argument that transportation improvements stimulate economic development has brought sometimes no resonance in lacking of a plausible theory on the conditions and process of economic development by transportation investment. This paper reviews the theory on regional differentiation of transportation system and shows why and how the installation of a new transportation system or the improvements of the old transportation quality differentiate the spatial order of economic activities. It presents the interaction between the change of transportation quality with introducing of definition "transportation value" as tool of its determination and economic activities following the regional differentiation process, which result means regional defferentiation of niveau of economic development.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.1
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• pp.148-156
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• 2014

The objective of this study is to compare NOx emissions from light duty diesel vehicles measured from on-road tests that conducted under various driving routes and seasonal conditions. We measured real-driving NOx emissions using PEMS, portable emissions measurement system, under the urban, rural and motorway road traffic conditions. On-road tests were repeated at summer, fall and winter season. The accumulated driving distance is more than 1,200 km per each vehicle. Route average NOx emission factors were compared among nine route-season combinations. The emission characteristics of each combinations were investigated using time series mass emission rates and vehicle operation-based emission rates and activities, which is based on U.S. EPA's MOVES model. Most concerned route-season combination is "urban road condition at summer", which shows two to eleven times higher NOx emissions than other combinations. The emission rates and activities under low speed operating conditions should be managed in order to reduce urban-summer NOx. From a NOx control strategy perspective, the exhaust gas recirculation, EGR, is observed to be properly operated under wide range of vehicle driving conditions in Euro-5 vehicles, even if the air conditioner turns on. In high power demanding conditions, the effect of overspeeding could be more critical than that of air conditioner activation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1D
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• pp.23-31
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• 2012

Busan Metropolitan City government has been implementing the local Bus Quasi-Public Operating policy since 2007. As a result of the policy, financial burden to cover financial deficit has become a big social issue. For successful settlement of the policy, the government should be able to gradually cut off the financial support for the deficit by continuously increasing the bus demand, which can be accomplished by providing more convenient bus services. The weather conditions that affect the public transportation demand include rain, fog and snow. They affect the mode choice for public transportation use, which in turn results in decrease in bus demand. In short, the adverse weather conditions result in significant profit loss of bus transportation, and consequently it financially burdens the City of Busan. In this research, the pattern of travelers' use of transportation modes given various weather conditions was analyzed. In addition, the reasons why people transfer from one to other transportation modes were analyzed by conducting a field survey, and policy implications on desirable public transportation facilities and transfer system were discussed.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.6
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• pp.874-878
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• 2013

Unlike Europe (particularly, Italy and Spain), where a number of studies have been conducted on the stressful effects of transport on rabbit welfare, few studies have been conducted on transportation of rabbits under hot, humid tropical conditions experienced in countries like Malaysia. We studied the effects of transportation in hot humid tropical conditions of Malaysia on physiometabolic changes in New Zealand white rabbits. Eighty experimental animals were divided into two groups of 40 bucks each and transported for either 3 or 1 h. Transportation caused a significant upsurge of aspartate aminotransferase, alanine aminotransferase and creatine kinase activities (p<0.001) though did not significantly affect lactate dehydrogenase (LDH) activity (p = 0.0706). Both transportation periods caused elevation in plasma glucose levels, lactic acidosis and dehydration as evidenced through elevated packed cell volume and plasma protein concentration. It was concluded that regardless of the duration, transport of rabbits under hot humid tropical conditions, resulted in heat distress since the rabbits showed hyperglycemia, hypercalcemia, lactacidemia, lymphocytopenia, dehydration and increase in blood enzyme activities.