• The Korean Journal of Rehabilitation Nursing
• /
• v.14 no.2
• /
• pp.118-128
• /
• 2011

Purpose: The purpose of this study was to explore the experiences of bereavement for main family members who had made and followed DNR decision for their family members. Method: This qualitative study was based on a grounded theory, and used in-depth interview techniques with the bereaved 10 main family members who had been treated and died under DNR order. Results: The causal condition of the family member was 'Releasing', and the main consequent phenomenon were 'Blaming self and ruminating'. The contextual condition was 'The memory of the deceased'. The action/reaction strategy was 'Purifying'. The intervening condition was 'Supporting system', and the consequence was 'Acceptance'. The experience after bereavement of the family member on DNR decision were rational processes that purified themselves and healed the guilt feeling about the decision from reflective assessment and response about DNR decision. Based on this results, the substantive theory 'Reflective self healing' was derived. Conclusion: The main family members in following DNR decision are more likely to have unhealthy emotional condition than others in normal bereavement process. But they overcame the grief of bereavement through reflective self healing process.

• Journal of Applied Reliability
• /
• v.17 no.3
• /
• pp.246-255
• /
• 2017

Purpose: This study proposes the optimal PM (preventive maintenance) policy of leased equipment for lessee's decision-making using two types of reliability condition. Methods: We consider reliability threshold based PM model. Equipment reliability is estimated and used as condition variable. The effect of repair for maintenance is imperfect and represented by age reduction factor. Results: We provide two PM policies. Policy 1 is focused on minimized total cost. This policy guarantees reliability threshold until last maintenance action. Policy 2 focus on maintaining reliability threshold during leased period. The proposed approach provides optimal reliability threshold under number of PM. Through result, we finally construct decision-making process for lessee using reliability threshold and end of reliability. Conclusion: This study provides two PM policy for lessee's decision-making. Through numerical example, we get a result of optimal reliability threshold, number of PM, optimum alternative under lessee's reliability condition.

• Asian Journal of Atmospheric Environment
• /
• v.5 no.4
• /
• pp.228-236
• /
• 2011

Since most Green House Gases (GHGs) and air pollutants are generated from the same sources, it will be cost-effective to develop a GHGs reduction plan in combination with simultaneous removal of air pollutants. However, effects on air pollutants reduction according to implementing any GHG abatement plans have been rarely studied. Reflecting simultaneous removal of air pollutants along with the GHGs emission reduction, this study investigated relative cost effectiveness among GHGs reduction action plans in Busan Metropolitan City. We employed the Data Envelopment Analysis (DEA), a methodology that evaluates relative efficiency of decision-making units (DMUs) producing multiple outputs with multiple inputs, for the investigation. Assigning each GHGs reduction action plan to a DMU, implementation cost of each GHGs reduction action plan to an input, and reduction potential of GHGs and air pollutants by each GHGs reduction action plan to an output, we calculated efficiency scores for each GHGs reduction action plan. When the simultaneous removal of air pollutants with the GHGs reduction were considered, green house supply-insulation improvement and intelligent transportation system (ITS) projects had high efficiency scores for cost-positive action plans. For cost-negative action plans, green start network formation and running, and daily car use control program had high efficiency scores. When only the GHGs reduction was considered, project priority orders based on efficiency scores were somewhat different from those when both the removal of air pollutants and GHGs reduction were considered at the same time. The expected action plan priority difference is attributed to great difference of air pollutants reduction potential according to types of energy sources to be reduced.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.27 no.4
• /
• pp.96-104
• /
• 2019

The response to climate change of international air transport industry might be initiated by ICAO's CORSIA (Carbon Offsetting and Reduction Scheme for International Aviation) which will impact on international airlines' flight operation behavior in the future. Though the airlines' efforts to reduce fuel consumption has been a major issue in economics of aviation industry, the improvement of fuel efficiency in flight operation will have additional impact on their profitability by introducing carbon emission cost. The fuel consumption in flight operation will be somewhat influenced by pilots' technical action for maneuvering aircraft during flight operation. This study will investigate pilots' behavior on decision for tactical aircraft control for mission flight. The data will be collected by the survey through sample pilots asking about their intention and perception on fuel savings during flight operations. The data will be analyzed by AHP process and the study will find out the elements and factors influencing pilots' behavior on technical decision of flight and their weights on fuel saving effects.

• Nuclear Engineering and Technology
• /
• v.52 no.1
• /
• pp.69-77
• /
• 2020

After the Fukushima Daiichi accidents, public concerns on nuclear safety and the corresponding burden of nuclear power plant licensees are increasing. In order to secure public trust and enhance the rationality of current safety regulation, we develop a risk-informed decision making (RIDM) framework for the Korean regulatory body. By analyzing all the regulatory activities for nuclear power plants in Korea, eight action items are selected for RIDM implementation, with appropriate procedures developed for each. For two items in particular - the accident sequence precursor analysis (ASPA) and the significance determination process (SDP) - two customized risk evaluation software has been developed for field inspectors and probabilistic safety assessment experts, respectively. The effectiveness of the proposed RIDM framework is demonstrated by applying the ASPA procedure to 35 unplanned scrams and the SDP to 24 findings from periodic inspections.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.11
• /
• pp.5449-5464
• /
• 2018

Recent works have validated the possibility of reducing the energy consumption in wireless heterogeneous networks, achieved by switching on/off some base stations (BSs) dynamically. In this paper, to realize energy conservation, the discrete time Markov Decision Process (DTMDP) is developed to match up the BS switching operations with the traffic load variations. Then, an asynchronous decision-making algorithm, which is based on the Bellman equation and the on/off priorities of the BSs, is firstly put forward and proved to be optimal in this paper. Through reducing the state and action space during one decision, the proposed asynchronous algorithm can avoid the "curse of dimensionality" occurred in DTMDP frequently. Finally, numerical simulations are conducted to validate the effectiveness and advantages of the proposed asynchronous on/off strategies.

• The Korean Journal of Financial Management
• /
• v.2 no.1
• /
• pp.21-34
• /
• 1986

The purpose of this study is to analyse the risk and uncertainty involved in the capital budgeting which is executed in long periods and requires massive capital expenditure. Under risk and uncertainty conditions, the estimates in the capital budgeting are random variables rather than known constants. Two approaches have emerged in performing economic analysis that explicitly incorporate risk and uncertainty conditions in the analysis. One approach is to develop a descriptive model which describes the economic performance of an individual investment alternative. But no recomendation would be forthcoming from the model. Rather, the decision-maker would be furnished descriptive information concerning each alternative; the final choice among the alternatives would required a separate action. The second approach is to develop a normative model which includes an objective function to be maximized or minimized. The output from the model prescribes the course of action to be taken. Owing to the fact that the normative approach considers the fitness of criteria for decision-making its reasonableness looks better. But it is almost imposible that we correctly and easily derive the individuals' utility function. So within we recognize the limits of the descriptive methods, it is more practicle to analyse the investment alternatives by sensitivity analysis.

• Asia pacific journal of information systems
• /
• v.32 no.2
• /
• pp.226-248
• /
• 2022

The existing model for sentiment analysis of product reviews learned from past data and new data was labeled based on training. But new data was never used by the existing system for making a decision. The proposed Aspect-based multi-agent Deep Reinforcement learning Sentiment Analysis (ADRSA) model learned from its very first data without the help of any training dataset and labeled a sentence with aspect category and sentiment polarity. It keeps on learning from the new data and updates its knowledge for improving its intelligence. The decision of the proposed system changed over time based on the new data. So, the accuracy of the sentiment analysis using deep reinforcement learning was improved over supervised learning and unsupervised learning methods. Hence, the sentiments of premium customers on a particular site can be explored to other customers effectively. A dynamic environment with a strong knowledge base can help the system to remember the sentences and usage State Action Reward State Action (SARSA) algorithm with Bidirectional Encoder Representations from Transformers (BERT) model improved the performance of the proposed system in terms of accuracy when compared to the state of art methods.

• Journal of Navigation and Port Research
• /
• v.38 no.6
• /
• pp.629-636
• /
• 2014

To minimize secondary damages from marine environment pollution resulting from marine accidents, International Maritime Organization(IMO) adopted "Guidelines on Places of Refuge(POR) for ships in need of assistance" as Resolution A.949(23) in it is 23rd General Assembly in 2003 and recommends Parties to the Organization designate PoR. This resolution suggests that they establish a "Decision-Making process" so as to provide reasonable PoR when disabled ships request use of PoR. Korea has not been performed introduce a PoR system in the country. Therefore, there is no decision-making process to deal with ships which need PoR. When Korea implements the PoR system in the future, the nation should establish a Decision-Making process to provide reasonable PoR in case ships in need of assistance request for PoR. In order to present what should be considered in the process of establishing a Decision-Making process for PoR in Korea in the future, in this study presents matters which should be considered in the process of founding PoR Decision-Making processes. When Korea tries to conduct POR system so that other countries' PoR Decision-Making process and the relating process of IMO and REMPEC (Regional Marine Pollution Emergency Response Centre for the Mediterranean Sea) were investigated and analyzed. In addition, in times of marine accident in Korea's sea areas, Korea's action manuals for marine accident which regulates management for an accident is analyzed and articles will be presented to be taken into account during establishing final PoR Decision-Making process.

• Journal of Radiation Protection and Research
• /
• v.29 no.1
• /
• pp.65-71
• /
• 2004

A multi-attribute utility analysis was investigated as a tool for the decision support of countermeasures in early phase of a nuclear accident. The utility function of attributes was assumed to be the second order polynomial expressions, and the weighting constant of attributes was determined using a swing weighting method. Because the main objective of this study focuses on the applicability of a multi-attribute utility analysis as a tool for the decision support of countermeasures in early phase of a nuclear accident, less quantifiable attributes were not included due to lack of information. In postulated accidental scenarios for the application of the designed methodology, the variation of the numerical values of total utility for the considered actions, e.g. sheltering, evacuation and no action, was investigated according to the variation of attributes. As a result, it was shown that the numerical values of total utility for the actions are distinctly different depending on the exposure dose and monetary value of dose. As increasing in both attributes, the rank of the numerical values of total utility increased for evacuation, which is more extreme action than for sheltering, while that of no action decreased. As expected probability of high dose is higher, the break-even values for the monetary value of dose, which are the monetary value of dose when the ranking of actions is changed, were lower. In audition, as aversion psychology for dose is higher, the break-even values for dose were lower.