• Journal of Auto-vehicle Safety Association
• /
• v.14 no.2
• /
• pp.70-74
• /
• 2022

This paper describes the development of a target vehicle state estimation algorithm using vehicle-to-vehicle (V2V) communication. Perceiving the state of the target vehicle has great importance for successful autonomous driving and has been studied using various sensors and methods for many years. V2V communication has advantage of not being constrained by surrounding circumstances relative to other sensors. In this paper, we adopt the V2V signal for estimating the target vehicle state. Since applying only the V2V signal is improper by its low frequency and latency, the signal is used as additional measured data to improve the estimation accuracy. We estimate the target vehicle state using Extended Kalman filter (EKF); a point mass model was utilized in process update to predict the state of next step. The process update is followed by measurement update when ego vehicle receives V2V information. The proposed study evaluated state estimation by comparing input V2V information in an experiment where the ego vehicle follows the target vehicle behind it.

• Electronics and Telecommunications Trends
• /
• v.33 no.1
• /
• pp.101-110
• /
• 2018

Based on the main technologies of the 4th Industrial Revolution, industries including the smart home, transportation, agriculture, factory, energy, and medical care industries are rapidly developing. Disaster management technologies and services based on state-of-the-art convergence technologies are being widely applied for the purposes of public safety. State-of-the-art scientific technologies including the Internet of Things (IoT) are expected to offer alternative solutions to pending issues of disaster and safety. Particularly in disaster management, a "prevention activity"to avoid and control disasters in advance is essential, and thus disaster prevention and safety monitoring technologies based on hyper-connected intelligence are fundamental for society during the 4th Industrial Revolution. IoT technologies are being actively applied and utilized in various fields to prevent social and natural disasters. In this article, we introduce the development trends of disaster prevention and safety monitoring technologies based on IoT technologies.

• Journal of the Korean Society of Safety
• /
• v.12 no.2
• /
• pp.70-79
• /
• 1997

This paper presents a study on the fuzzy linguistic variable based approach for safety assessment of human body in ELF electromagnetic field considering power system states. To cope with the demand in modern industry, the power system becomes larger in scale, higher in voltage. The advent of high voltage system has increased the relative importance of field effects. The analysis of ELF electromagnetic field based on Quasi-Static Method is introduced while the power system is included to model the expected and/or unexpected uncertainty caused by the load fluctuation and parameter changes. In order to analyze the power system, Monte Carlo simulation method and contingency analysis method are adopted in normal state and alert state, respectively. In the safety assessment of human body, the approach based on fuzzy linguistic variable is employed to overcome the shortcomings resulting from a crisp set concept. The suggested scheme is applied to a sample system(modified IEEE 14 bus system) to validate the usefulness.

• 한국가스학회:학술대회논문집
• /
• 2004.11a
• /
• pp.158-163
• /
• 2004

• Journal of the Ergonomics Society of Korea
• /
• v.33 no.2
• /
• pp.77-86
• /
• 2014

Objective: The purpose of this study is to grasp the fundamental structure of incident occurrence in nuclear organizations based on system thinking, and analyze how various causes are interrelated in terms of the causal loop diagram. Background: The recent domestic and overseas nuclear power plant-related incidents and accidents are directly or indirectly associated with safety culture, and thus effective plans for the improvement of safety culture are being called for. While the safety of a nuclear power plant is highly dependent upon technology and equipment, the utilization, maintenance and inspection of the technology and equipment are conducted by workers of the nuclear power plant. Method: Methodology of system thinking perspective using causal loop analysis. Results: As a result of the analysis, first, it turned out that the fundamental cause of incident occurrence in nuclear organizations is time constraint. Second, if a workload of workers increases, their adherence to regulations and procedures comes to be reduced due to time constraint. Third, it is needed, through organizational learning education, to increase actions made from thoughts considering safety as the utmost priority in advance. Fourth, it is necessary to improve professionalism by enhancing educational programs for new workers, and to develop various scenarios with which they can cope with certain situations. Application: This paper provides a base for system dynamics simulation model for future study.

• The Journal of the Korea Contents Association
• /
• v.17 no.9
• /
• pp.331-340
• /
• 2017

The purpose of this study was to analyze and clarify the concept of psychological safety in nursing simulation education so that it can contribute to learning environment that guarantee psychological safety for nursing students. Using Walker & Avant's concept analysis framework, 15 research articles about psychology safety were included in this study. There were four definable attributes of psychological safety: 1) comfortable state feeling or status; 2) State that can perform without fear; 3) Sense of trust toward the organization; and 4) Feeling that there will be no harm to oneself. When antecedents, attributes, and consequences of psychological safety is considered when shaping simulation education environment, the learning effect for nursing students is expected to be maximized.

• Proceedings of KOSOMES biannual meeting
• /
• 2005.05a
• /
• pp.195-208
• /
• 2005

The flag State is primarily responsible for implementing international maritime conventions(IMO conventions) and national laws and other standards as far as its own vessels are concerned, on the other hand the port State exercise its rights for the safety and marine environment under international law especially UNCLOS within port and territorial sea. In particular, the port State may take appropriate measures including detention of ships identified as sub-standard vessels which are considered as port State's supplementary role aiming for implementing international and national and regulations. But in the course of implementing port state control, international disputes may happen between port state, coastal state and flag state in spite of making all possible efforts to avoid these disputes. This paper aims to consider legal grounds on port state control(PSC) in international conventions and national laws concerned and deals with contradictions between international and national law arising from exercising PSC by port state control officers(PSCOs).

• International Journal of Railway
• /
• v.8 no.1
• /
• pp.5-9
• /
• 2015

Reliability based limit state design method is replacing traditional deterministic designs such as allowable stress design and/or ultimate strength design methods in world trends. European design code(Eurocode) has adopted limit state design, and Korea road bridge design standard has also recently been transferred to limit state design method. In this trend, Korea railroad design standard is also preparing for adopting the same design concept. While safety factors are determined empirically in traditional design, load combinations as well as load factors are determined by solving limit state equations. General partial safety factors are evaluated by using AFORM(Advanced First Order Reliability Method) in the reliability based limit state design method. In this study sensitivity analysis is carried out for a dead load factor and a live load factor. Relative precisions of the dead load and the live load factors are discussed prior to the AFORM analysis. Furthermore the sectional forces of design and the material quantities required by two different design methods are compared for a PSC box girder railway bridge.

• International conference on construction engineering and project management
• /
• 2022.06a
• /
• pp.640-648
• /
• 2022

In the United States, the Safety Rest Areas (SRAs) were introduced as highway roadside infrastructures in the early 1900s. The State Departments of Transportation (DOTs) operate/maintain their SRAs using different methods. The Washington DOT used the in-house workforce method for over 20 years, whereas some states moved to Performance-Based Contracting (PBC) from the in-house workforce to save cost primarily. Several existing studies claimed that using the PBC approach saved costs on several highway assets. Thus, the principal objective of this study is to compute and compare the unit operating/maintenance cost of SRAs using the in-house workforce method (in Washington state) with the PBC approach (in other states). The findings of this study show that the average annual cost using the PBC approach was much more than the average annual cost using the in-house workforce approach. The findings also show that in Washington state, the 'Labor Cost' category was a key expenditure, which is statistically higher than other categories. The 'Labor Cost' was followed by the 'Other Services', and then 'Materials and Supplies' and 'Equipment.' The study's findings indicated that outsourcing does not always save costs for agencies. The study findings may help transportation construction/maintenance professionals select a cost-effective approach for their future planning.

• Safety and Health at Work
• /
• v.14 no.3
• /
• pp.303-308
• /
• 2023

Background: Occupational workers at altitudes are more prone to falls, leading to catastrophic outcomes. Acrophobia, height-related anxiety, and affected executive functions lead to postural instabilities, causing falls. This study investigated the effects of repeated virtual height exposure and training on cognitive processing and height-related anxiety. Methods: Twenty-eight healthy volunteers (age 20.48 ± 1.26 years; mass 69.52 ± 13.78 kg) were recruited and tested in seven virtual environments (VE) [ground (G), 2-story altitude (A1), 2-story edge (E1), 4-story altitude (A2), 4-story edge (E2), 6-story altitude (A3), and 6-story edge (E3)] over three days. At each VE, participants identified occupational hazards present in the VE and completed an Attitude Towards Heights Questionnaire (ATHQ) and a modified State-Trait Anxiety Inventory Questionnaire (mSTAIQ). The number of hazards identified and the ATHQ and mSTAIQ scores were analyzed using a 7 (VE; G, A1, A2, A3, E1, E2, E3) x 3 (DAY; DAY 1, DAY 2, DAY 3) factorial repeated measures analysis of variance. Results: The participants identified the lowest number of hazards at A3 and E3 VEs and on DAY 1 compared to other VEs and DAYs. ATHQ scores were lowest at G, A1, and E1 VEs. Conclusion: Cognitive processing is negatively affected by virtual altitudes, while it improves with short-term training. The features of virtual reality, such as higher involvement, engagement, and reliability, make it a better training tool to be considered in ergonomic settings. The findings of this study will provide insights into cognitive dual-tasking at altitude and its challenges, which will aid in minimizing occupational falls.