• The Journal of Information Systems
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• v.32 no.3
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• pp.225-251
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• 2023

Purpose The purpose of this study is to examine the future direction of in-vehicle app development and service, the relationship between potential customers' intention to use and the factors that affect it was explored. It was also checked whether the two types of app development platform and the experience of the existing smartphone app platform had a moderating effect on these relationships. Design/methodology/approach Data was gathered through surveys, collecting responses from 904 potential consumers of vehicle app services in Korea. Structural equation modeling was utilized to analyze the data. Findings According to the empirical analysis result, it was found that potential customers considered enjoyment as the most important benefit factor in in-vehicle app service, and the most important external factor affecting enjoyment was functional compatibility with smartphone. The type of vehicle app development platform did not have a meaningful moderating effect on the factor relationship, whereas the smartphone app platform experience showed a meaningful moderating effect on the relationship between factors. It was analyzed that the risk of app performance, personal information privacy, and driving safety data did not have a negative effect on the intention to use the vehicle app service.

• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4477-4490
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• 2023

Fuel locking mechanisms (FLMs) are essential in upward-flow research reactors to prevent accidental fuel separation from the core during reactor operation. This study presents a novel design concept for a remotely controlled plate-type nuclear fuel locking mechanism. By employing electromagnetic field analysis, we optimized the design of the electromagnet for fuel unlocking, allowing the FLM to adapt to various research reactor core designs, minimizing installation space, and reducing maintenance efforts. Computational flow analysis quantified the drag acting on the fuel assembly caused by coolant upflow. Subsequently, we performed finite element analysis and evaluated the structural integrity of the FLM based on the ASME boiler and pressure vessel (B&PV) code, considering design loads such as dead weight and flow drag. Our findings confirm that the new FLM design provides sufficient margins to withstand the specified loads. We fabricated a prototype comprising the driving part, a simplified moving part, and a dummy fuel assembly. Through basic operational tests on the assembled components, we verified that the manufactured products meet the performance requirements. This remote-controlled micro locking mechanism holds promise in enhancing the safety and efficiency of plate-type nuclear fuel operation in upflow research reactors.

• Structural Engineering and Mechanics
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• v.91 no.1
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• pp.25-38
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• 2024

After the mainshock, whether the train can be allowed to pass the bridges plays an important role in ensuring the transport of supplies and rescue works for example, in the "12 May" earthquake in China, after evaluation, the bridge was still used for transportation in rescue at a very slow speed, engineers usually evaluate whether the train can pass the bridge safely based on the experience, lacks sufficient calculation basis and does not fully consider the risk caused by aftershocks. To address this issue, this paper comprehensively considers the randomness of track irregularity, the randomness of aftershock intensity and other multiple random sources in train-bridge interaction system (TBIS). The sensitivity of train to various random parameters after earthquake is analyzed from the perspective of probability, the most sensitive random variable in this paper is PGA of aftershocks, both for bridge and trailer car, With the increase of epicentral distance, the sensitivity of PGA will decrease, and correspondingly, for trailer car, the sensitivity of other random variables will increase, research in this paper provides a basis for the subsequent random analysis of post-earthquake driving safety.

• Nuclear Engineering and Technology
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• v.56 no.5
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• pp.1687-1697
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• 2024

This study presents the Supporting platform for reactor fine flow characteristics calculation and analysis (Cilian platform), a user-friendly tool that supports the analysis and optimization of pressurized water reactor (PWR) cores with mixing vanes using computational fluid dynamics (CFD) computing. The Cilian platform allows for easy creation and optimization of PWR's main CFD calculation schemes and autonomously manages CFD calculation and analysis of PWR cores, reducing the need for human and computational resources. The platform's key features enable efficient simulation, rapid solution design, automatic calculation of core scheme options, and streamlined data extraction and processing techniques. The Cilian platform's capability to call external CFD software reduces the development time and cost while improving the accuracy and reliability of the results. In conclusion, the Cilian platform exemplifies an innovative solution for efficient computational fluid dynamics analysis of pressurized water reactor (PWR) cores. It holds great promise for driving advancements in nuclear power technology, enhancing the safety, efficiency, and cost-effectiveness of nuclear reactors. The platform adopts a modular design methodology, enabling the swift and accurate computation and analysis of diverse flow regions within core components. This design approach facilitates the seamless integration of multiple computational modules across various reactor types, providing a high degree of flexibility and reusability.

• Journal of Platform Technology
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• v.11 no.6
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• pp.13-20
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• 2023

Regularly inspecting vehicle tires' condition is imperative for driving safety and comfort. Poorly maintained tires can pose fatal risks, leading to accidents. Unfortunately, manual tire visual inspections are often considered no less laborious than employing an automatic tire inspection system. Nevertheless, an automated tire inspection method can significantly enhance driver compliance and awareness, encouraging routine checks. Therefore, there is an urgency for automated tire inspection solutions. Here, we focus on developing a deep learning (DL) model to predict cracked tires. The main idea of this study is to demonstrate the comparative analysis of DenseNet121, VGG-19 and EfficientNet Convolution Neural Network-based (CNN) Transfer Learning (TL) and suggest which model is more recommended for cracked tire classification tasks. To measure the model's effectiveness, we experimented using a publicly accessible dataset of 1028 images categorized into two classes. Our experimental results obtain good performance in terms of accuracy, with 0.9515. This shows that the model is reliable even though it works on a dataset of tire images which are characterized by homogeneous color intensity.

• Korean Journal of Environmental Agriculture
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• v.34 no.2
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• pp.134-138
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• 2015

BACKGROUND: In recent years, several researchers have focused on odour control methods to remove the harmful chemicals from chemical accidents and incidents. The present work deals with the system development of the hazardous. METHODS AND RESULTS: For on-site removal of hazardous gaseous materials from chemical accidents, mobile vortex wet scrubber was designed with water vortex process to absorb the gas into the water. The efficiency of the mobile vortex wet scrubber was evaluated using water spray and 25% ammonia solution. The inlet air velocity (gas flow rate) was according to the damper angle installed within the hood and with increase of gas flow rate, consequently the absorption efficiency was markedly decreased. In particular, when 25% ammonia solution was exposed to the hood inlet for 30 min, the water pH within the scrubber was changed from 7 to 12. Interestingly, although the removal efficiency of ammonia gas exhibited approximately 80% for 5 min, its efficiency in 10 min showed the greatest decrease with 18%. Therefore, our results suggest that the ammonia gas may be absorbed with the driving force of scrubbing water in water vortex process of this scrubber. CONCLUSION: When chemical accidents are occurred, the designed compact scrubber may be utilized as effective tool regarding removal of ammonia gas and other volatile organic compounds in the scene of an accident.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.1
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• pp.19-29
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• 2022

The result of a questionnaire survey conducted on fishermen using coastal fish traps shows that fall accidents during trap dropping and pulling constitute the highest proportion of accidents at 42.1 %, whereas slipping accidents on the deck or stricture accidents to the body due to the trap winding device constitute 21.1 % each. In addition, 53.2 % of all surveyed subjects responded that trap pulling is the most dangerous task, followed by fish sorting 33.8 %, and trap dropping 9.1 %. As for the main items requested by fishermen for improving the trap winding device, 36.8 % indicated a method to easily lift the trap from the water to the work deck, and 31.6 % indicated a method to overcome the rope tension and prevent slip when pulling the trap to reduce the accidents. The small trap fishing vessel winding device proposed herein can increase the winding force by strengthening the rope contact area and friction coefficient via an appropriate contact angle between the driving roller of the winding device and the rope. When the contact angles between the driving roller and the rope are 1°, 5°, 9°, 14° and 19°, the rope tension showed a difference according to each contact angle. When the contact angle is 9°, the rope tension is the highest at 392.62 kgf. Based on these experimental results, a prototype winding device is manufactured, and 25 traps are installed on a rope with a total length of 100 m at 4 m intervals in the sea, and then the rope tension is measured during trap pulling. As a result, the rope tension increases rapidly at the initial stage of trap pulling and shows the highest value of 31.89 kgf, which subsequently decreases significantly. Therefore, it is appropriate to design the winding force of a small trap fishing vessel winding device based on the maximum tension value of the rope specified at the beginning of the trap pulling operation.

• Journal of Internet Computing and Services
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• v.15 no.3
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• pp.63-69
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• 2014

For the safety messages in IEEE 802.11p vehicles network environment(WAVE), strict periodic beacon broadcasting requires status advertisement to assist the driver for safety. WAVE standards apply multiple radios and multiple channels to provide open public road safety services and improve the comfort and efficiency of driving. Although WAVE standards have been proposed multi-channel multi-radio, the standards neither consider the WAVE multi-radio environment nor its effect on the beacon broadcasting. Most of beacon broadcasting is designed to be delivered on only one physical device and one control channel by the WAVE standard. also conflict-free channel assignment of the fewest channels to a given set of radio nodes without causing collision is NP-hard, even with the knowledge of the network topology and all nodes have the same transmission radio. Based on the latest standard IEEE 802.11p and IEEE 1609.4, this paper proposes an interference aware-based channel assignment algorithm with Nash bargaining solution that minimizes interference and increases throughput with wireless mesh network, which is deigned for multi-radio multi-cahnnel structure of WAVE. The proposed algorithm is validated against numerical simulation results and results show that our proposed algorithm is improvements on 8 channels with 3 radios compared to Tabu and random channel allocation algorithm.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.1
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• pp.117-130
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• 2017

Bicycles are leading to serious accidents in the event of a side collision, and it is very important to prevent accidents in advance because it is difficult to actively deal with them in a dangerous situation. As a part of the bicycle safety driving support technology, this study establishes bicycle accidents dangerous zone based on bicycle accident data and road property information of digital map nationwide and provides timely safety information to cyclists. The point selected by using actual accident data was called 'dangerous zone', and the potential accident occurrence point generated by modeling based on this 'dangerous zone' was called 'logical dangerous zone'. As a result of the research on the Designation of Logical Bicycle Accident Dangerous Zone, the regional specificity of the bicycle accident points across the nation was generalized to the form of the logical dangerous zone through the network data.

• Journal of Bio-Environment Control
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• v.4 no.1
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• pp.17-24
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• 1995

This study was carried out to make fundamental data for structural safety test of pipe- houses. Experiment on the stress distribution of pipe- houses was conducted to find suitable structural analysis model by examination of end support conditions of pipe. Besides, the loading test and the pile driving test were done to find pull-out capacity and bearing capacity of pipe on the assumption that pipe is pile foundation. For single span pipe - house, the theoretical results assuming the end support condition of pipe is fixed under ground agreed closely with the experimental results of stress distribution. On the other hand for double span pipe -house, the end support conditions of pipe were fixed support when vertical load is applied, and hinged one when horizontal load is applied. The pull - out capacity and allowable bearing capacity of the pipe portion that was buried in the grounds that were soft soil of paddy field and medium or hard soils of dry field derived from experimental results.