• Asia pacific journal of information systems
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• v.19 no.2
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• pp.117-137
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• 2009

Recently, intelligent traffic information systems have enabled people to forecast traffic conditions before hitting the road. These convenient systems operate on the basis of data reflecting current road and traffic conditions as well as distance-based data between locations. Thanks to the rapid development of ubiquitous computing, tremendous context data have become readily available making vehicle route planning easier than ever. Previous research in relation to optimization of vehicle route planning merely focused on finding the optimal distance between locations. Contexts reflecting the road and traffic conditions were then not seriously treated as a way to resolve the optimal routing problems based on distance-based route planning, because this kind of information does not have much significant impact on traffic routing until a a complex traffic situation arises. Further, it was also not easy to take into full account the traffic contexts for resolving optimal routing problems because predicting the dynamic traffic situations was regarded a daunting task. However, with rapid increase in traffic complexity the importance of developing contexts reflecting data related to moving costs has emerged. Hence, this research proposes a framework designed to resolve an optimal route planning problem by taking full account of additional moving cost such as road traffic cost and weather cost, among others. Recent technological development particularly in the ubiquitous computing environment has facilitated the collection of such data. This framework is based on the contexts of time, traffic, and environment, which addresses the following issues. First, we clarify and classify the diverse contexts that affect a vehicle's velocity and estimates the optimization of moving cost based on dynamic programming that accounts for the context cost according to the variance of contexts. Second, the velocity reduction rate is applied to find the optimal route (shortest path) using the context data on the current traffic condition. The velocity reduction rate infers to the degree of possible velocity including moving vehicles' considerable road and traffic contexts, indicating the statistical or experimental data. Knowledge generated in this papercan be referenced by several organizations which deal with road and traffic data. Third, in experimentation, we evaluate the effectiveness of the proposed context-based optimal route (shortest path) between locations by comparing it to the previously used distance-based shortest path. A vehicles' optimal route might change due to its diverse velocity caused by unexpected but potential dynamic situations depending on the road condition. This study includes such context variables as 'road congestion', 'work', 'accident', and 'weather' which can alter the traffic condition. The contexts can affect moving vehicle's velocity on the road. Since these context variables except for 'weather' are related to road conditions, relevant data were provided by the Korea Expressway Corporation. The 'weather'-related data were attained from the Korea Meteorological Administration. The aware contexts are classified contexts causing reduction of vehicles' velocity which determines the velocity reduction rate. To find the optimal route (shortest path), we introduced the velocity reduction rate in the context for calculating a vehicle's velocity reflecting composite contexts when one event synchronizes with another. We then proposed a context-based optimal route (shortest path) algorithm based on the dynamic programming. The algorithm is composed of three steps. In the first initialization step, departure and destination locations are given, and the path step is initialized as 0. In the second step, moving costs including composite contexts into account between locations on path are estimated using the velocity reduction rate by context as increasing path steps. In the third step, the optimal route (shortest path) is retrieved through back-tracking. In the provided research model, we designed a framework to account for context awareness, moving cost estimation (taking both composite and single contexts into account), and optimal route (shortest path) algorithm (based on dynamic programming). Through illustrative experimentation using the Wilcoxon signed rank test, we proved that context-based route planning is much more effective than distance-based route planning., In addition, we found that the optimal solution (shortest paths) through the distance-based route planning might not be optimized in real situation because road condition is very dynamic and unpredictable while affecting most vehicles' moving costs. For further study, while more information is needed for a more accurate estimation of moving vehicles' costs, this study still stands viable in the applications to reduce moving costs by effective route planning. For instance, it could be applied to deliverers' decision making to enhance their decision satisfaction when they meet unpredictable dynamic situations in moving vehicles on the road. Overall, we conclude that taking into account the contexts as a part of costs is a meaningful and sensible approach to in resolving the optimal route problem.

• Journal of Radiation Protection and Research
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• v.33 no.4
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• pp.127-134
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• 2008

Potential economic impact of a hypothetical severe accident at a nuclear power plant(Uljin units 3/4) was estimated by applying the Delphi method, which is based on the expert judgements and opinions, in the process of quantifying uncertain factors. For the purpose of this study, it is assumed that the radioactive plume directs the inland direction. Since the economic risk can be divided into direct costs and indirect effects and more uncertainties are involved in the latter, the direct costs were estimated first and the indirect effects were then estimated by applying a weighting factor to the direct cost. The Delphi method however subjects to risk of distortion or discrimination of variables because of the human behavior pattern. A mathematical approach based on the Bayesian inferences was employed for data processing to improve the Delphi results. For this task, a model for data processing was developed. One-dimensional Monte Carlo Analysis was applied to get a distribution of values of the weighting factor. The mean and median values of the weighting factor for the indirect effects appeared to be 2.59 and 2.08, respectively. These values are higher than the value suggested by OECD/NEA, 1.25. Some factors such as small territory and public attitude sensitive to radiation could affect the judgement of panel. Then the parameters of the model for estimating the direct costs were classified as U- and V-types, and two-dimensional Monte Carlo analysis was applied to quantify the overall economic risk. The resulting median of the overall economic risk was about 3.9% of the gross domestic products(GDP) of Korea in 2006. When the cost of electricity loss, the highest direct cost, was not taken into account, the overall economic risk was reduced to 2.2% of GDP. This assessment can be used as a reference for justifying the radiological emergency planning and preparedness.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.3
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• pp.679-690
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• 2015

The need to remove the cause of traffic accidents by improving the engineering system for a vehicle and the road in order to minimize the accident hazard. This is likely to cause traffic accident continue to take a large and significant social cost and time to improve the reliability and efficiency of this generally poor road, thereby generating a lot of damage to the national traffic accident caused by improper environmental factors. In order to minimize damage from traffic accidents, the cause of accidents must be eliminated through technological improvements of vehicles and road systems. Generally, it is highly probable that traffic accident occurs more often on roads that lack safety measures, and can only be improved with tremendous time and costs. In particular, traffic accidents at intersections are on the rise due to inappropriate environmental factors, and are causing great losses for the nation as a whole. This study aims to present safety countermeasures against the cause of accidents by developing an intersection Traffic safety evaluation model. It will also diagnose vulnerable traffic points through BPA (Back -propagation algorithm) among artificial neural networks recently investigated in the area of artificial intelligence. Furthermore, it aims to pursue a more efficient traffic safety improvement project in terms of operating signalized intersections and establishing traffic safety policies. As a result of conducting this study, the mean square error approximate between the predicted values and actual measured values of traffic accidents derived from the BPA is estimated to be 3.89. It appeared that the BPA appeared to have excellent traffic safety evaluating abilities compared to the multiple regression model. In other words, The BPA can be effectively utilized in diagnosing and practical establishing transportation policy in the safety of actual signalized intersections.

• Fashion & Textile Research Journal
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• v.16 no.6
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• pp.945-953
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• 2014

This study aims to develop protective pants to relieve impact from falls and to present basic data for the development. The survey results are as follows; First, 45% of the respondents were in their 60s and 55% of them were in their over 70s and older. Also, 64% of them have fallen once for the past year and 36% of them have fallen twice or more. The older they were, the more there were those who have fallen twice or more. This indicated the older people has experienced more fall accidents again after a initial fall accident. Second, as per accident situations, the survey showed that fall accidents happened the most in the winter and in the afternoon (12-18 pm). Also, it happened on a street mostly and they were wearing sneakers or hiking boots when they got a hurt slipped in a front or side by missing their step in a walk. The injury areas are mostly knee and ankle. They had the bruises or a sprain in their knee and ankle mostly. The rate of bone fracture was 19.5%. Therefore, the protection area to falls in lower body is the knee. But hip and hip joint should be protected with knee as well because those are usually be broken when it is damaged. Third, approximately 80% of those who were hospitalized for treatment had surgery. Patients who had surgery were rather in their over 70s than in their 60s. The older they were, the more serious their fracture was. The period of hospital or outpatient treatment is more than three weeks in many cases. They responded their health got worse after falls. Aftereffects of accidents were physical discomfort, anxiety and medical costs. Falls to the old makes physical damage, psychological damage, which cause reduced physical activity and the increased cost of health care with economic losses. So it results on a negative impact on the life of the old. Fourth, elderly females were rarely aware of impact protective clothing and they have never purchased such clothing. For impact protective pants, the major consideration was suitable design for their body types. They liked casual style with front or side pockets and simple designs without any patterns or decorations. As per pants materials, they responded that they need functionality, activity and elasticity. Among the functional points, insulation of cloths are considered importantly, so the heat reservance of material in the impact protective pants should be considered carefully.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.4
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• pp.243-251
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• 2015

Nuclear power is currently the second largest power supply method in Korea and the number of nuclear power plants are planned to be increased as well. However, clear management policy for spent fuels generated from nuclear power plants has not yet been established. The back-end fuel cycle, associated with nuclear material flow after nuclear reactors is a collection of technologies designed for the spent fuel management and the spent fuel management policy is closely related with the selection of a nuclear fuel cycle. Cost is an important consideration in selection of a nuclear fuel cycle and should be determined by adding external cost to private cost. Unlike the private cost, which is a direct cost, studies on the external cost are focused on nuclear reactors and not at the nuclear fuel cycle. In this research, external cost indicators applicable to nuclear fuel cycle were derived and quantified. OT (once through), DUPIC (Direct Use of PWR SF in CANDU), PWR-MOX (PWR PUREX reprocessing), and Pyro-SFR (SFR recycling with pyroprocessing) were selected as nuclear fuel cycles which could be considered for estimating external cost in Korea. Energy supply security cost, accident risk cost, and acceptance cost were defined as external cost according to precedent and estimated after analyzing approaches which have been adopted for estimating external costs on nuclear power generation.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.3
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• pp.38-49
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• 2015

Seoul has 424 traffic fatalities in 2010 and 227 of them related to pedestrian crashes. In addition, it revealed that 40% of pedestrian fatalities occurred during jaywalking. Through the effective methods preventing jaywalking can save lots of people, and it can reduce social costs pertinent to pedestrian crashes. Therefore, this study is to suggest the methods preventing jaywalking through conducting literature reviews, human factors with pedestrian and vehicle characteristics, as well as geometric features of accident site or spot. Firstly, in order for examining the contributing factors of accident, this research conducts statistical analysis on pedestrian accidents specifically in jaywalking. Secondly, the analysis on human factors about pedestrian and drivers revealed that drivers with high speed play pivotal roles in pedestrian fatalities. Thirdly, Road and environment factors showed both expected and contradictory results through analyzing total numbers of lane or dry/icy pavement conditions. Consequently, this study can be used to prevent and alleviate pedestrian accidents as well as expected to be applied to future researches about pedestrian safety facilities.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.6
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• pp.1-13
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• 2018

The number of deaths in Korea is higher than the OECD average. Therefore, an e-Call system is being developed as a vehicle ICT-based emergency rescue system that automatically detects an accident in the event of a vehicle accident and transmits related information to the center. In order to overcome the limitations of social acceptability and function of e-Call system, we propose a model that allows users to be aware of the necessity of service voluntarily. We predicted the market share of e-call services according to the proposed business model and analyzed it through B/C analysis. Benefits are calculated on a penetration basis, and device purchase and communications costs are calculated for each period. B/C analysis shows that pessimistic scenarios are 0.98 in 2025 and 1.01 in 2030. In an optimistic scenario, it is 1.05 in 2025 and 1.20 in 2030, which is more economical.

• Environmental and Resource Economics Review
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• v.31 no.4
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• pp.693-710
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• 2022

Social interest in occupational safety and health is increasing due to ESG management and the implementation of the Serious Accidents Punishment Act. This study examines the current status of occupational accidents, which is the safety level of energy companies, and the impact of occupational accidents on the management performance (sales per capita, operating profit per capita, operating margin per capita) of energy companies over the period of 2015 to 2021 was empirically analyzed. As a result of the analysis, the level of occupational accidents in the 157 energy companies to be analyzed was lower than the occupational injury accident rate in Korea, but the disease rate was high.As a result of analyzing the impact of occupational accidents on management performance, it is estimated that an increase in the occupational accident rate reduces per capita sales, per capita operating profit, and gross margin rate.Through this study, the vulnerability of energy companies to occupational accidents was confirmed, and the direct and indirect costs of occupational accidents quantified the negative impact on management performance.Referring to the results of this study, energy companies should strengthen their efforts to prevent occupational accidents by increasing investment in safety and health to protect the lives of valuable workers and create sustainable business performance.

• International Journal of Highway Engineering
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• v.13 no.3
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• pp.75-82
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• 2011

There is the uncertain period of the construction in case of the products meeting the quality standard of KS M 6080, the quality is degraded because of the abrasive loss of the paint caused by vehicle tires as the traffic amount increases and of the loss and detachment of the glass beads providing the retroreflective function. The abrupt degradation of visibility causes the high frequency of traffic accidents at night and increases the traffic accident rate. Additional supplementary construction induces the direct material and construction costs. As the more cost induction effect than the direct cost, the traffic jam caused by the additional construction increases the indirect social costs such as time cost and vehicle cost. Hence, the study is concerned with performing the abrasion resistance test based on the EN 1436 standard to check and improve the quality of various road marking materials resulting in improving the durability of road marking materials. However, even though the difference in the durability lifetime of resins(binders) is bibliographically or theoretically clear, there was no difference in the durability lifetime (retroreflectivity aspect) of the road marking paint using these binders. The reason is that the bonding of beads was very insufficient or that the cross density caused by crack or freshness was low. Moreover, the measured wet retroreflectivity was distributed as the Rw3 or higher class in average on the basis of EN 1436 but was very insufficient on the basis of the minimum wet threshold retroreflectivity with 100mcd/($m^2{\cdot}lx$) managed overseas.

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.490-494
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• 2017

With increasing the number of vehicles, the accident rate also goes up and the damaged vehicles should be painted as a final repair process. At the painting stage the solvent-based paint causes environmental problems. To overcome these problems waterborne refinish paint is frequently used recently. However, for waterborne refinish, the costs of insurance coverage are too expensive, and insurance reimbursement costs could be burdensome. Because of the high price of aquatic paint treatment, the service shop might charge the malicious service price. In this study, the surfactant of Surfynol 104, which is the component in the paint, was used as an indicator whether the vehicle was painted with waterborne paint. The specimen was quantitatively analyzed to contain 0.38% of the surfactant through the standard addition method with isotope substituted internal standard (IS) of fluranthene-d10 by curie point pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS).