• 전기학회논문지P
• /
• 제64권4호
• /
• pp.220-230
• /
• 2015

Rolling stock RAMS is a field of engineering which integrates reliability, availability, maintainability and safety (RAMS) characteristics into an inherent product design property through rolling stock system engineering process. It is implemented to achieve operational objectives successfully, and recently the RAMS has become a rapidly growing engineering discipline because it has a great potential to ensure safety and improve cost effectiveness. However, the Korean rolling stock industry has not yet implemented RAMS management in the rolling stock engineering process, despite the issue having been addressed since the introduction of the KTX. Thus, this paper discusses the processes, methods and techniques for RAMS assessment in three parts. Firstly, it outlines a process of the overall RAMS performance assessment for achieving technical RAMS design criteria. Secondly, it discusses a process for assessing the operational RAM and allocating the RAM. This paper also proposes a model for assessing safety-based risk management, which includes five analytic techniques for identifying the causes and consequences of a system failure. Finally, a case example is provided for the risk assessment of the pneumatic braking device.

• 한국국방경영분석학회지
• /
• 제7권1호
• /
• pp.53-80
• /
• 1981

This paper explores a rational investment decision model in sequential capital allocation process under capital rationing. A method is proposed for measuring the new investment decision factor which is the flexibility that describes the future availability of invested funds. This flexibility is important in sequential decision process. Also presented is a multiobjective (MO) decision model into which flexibility is incorporated with the profit and risk factors. The effectiveness of this criterion is compared with the expected present value and the mean-semivariance criteria through a simulation model.

• 대한한방부인과학회지
• /
• 제24권4호
• /
• pp.105-113
• /
• 2011

Objectives: To examine the current status of clinical research in oriental medicine, and to assess 'risk of bias'(ROB) of randomized clinical trials(RCTs) in oriental medicine in Korea. Methods: Special committee for EBM, KOMS(Korean Oriental Medicine Society) reviewed 17 journals related to oriental medicine in Korea (from the first issue to May 2010), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 2, 2010), and PubMed (1966 to May 2010). Then we selected eligible RCTs in terms of oriental medicine, and assessed 'risk of bias'. Results: We reviewed 12,653 articles from the 17 journals, and 41 articles from CENTRAL and PubMed. After non-clinical articles were excluded, 1,004 articles were left. Among them, the number of eligible studies in terms of oriental medicine was 306. In these eligible studies, 130 were RCTs. Of RCTs, 69 were on acupuncture, 25 on herbal medicine. The proportion of 'unclear' is high in the criteria of 'Allocation concealment', 'Blinding of participants and personnel', 'Blinding of outcome assessment' and 'Other bias'. On the other hand, 'low' has high in the criteria of 'Incomplete outcome data' and 'Selective reporting'. Conclusions: Risk of bias on oriental medicine is unclear in terms of 'allocation concealment' and 'blinding'. For high-quality research in oriental medicine, further research should be needed on randomization and blinding in the RCTs.

• 한국기후변화학회지
• /
• 제9권4호
• /
• pp.325-342
• /
• 2018

The Korea Emissions Trading Scheme ( K-ETS), which manages roughly 70% of the greenhouse gas emissions in South Korea, was initiated in 2015, after implementation of its 1st basic plan and the 1st allocation plan (2014) for the 1st phase (2015-2017). During the three and a half years since the launch of K-ETS, there have been critical policy change such as adjustment of the institutions involved, development and revision of the 2030 national GHG reduction roadmap, and change in the allocation plans. Moreover, lack of liquidity and fluctuation of carbon prices in the K-ETS market during this period has forced the Korean government to adjust the flexibility mechanism and auction permits of the market stability reserve. To evaluate the policy change in the K-ETS regarding conformance to its objectives, this study defines three objectives (Environmental Effectiveness, Cost Effectiveness and Economic Efficiency) and ten indicators. Evaluation of Environmental Effectiveness of K-ETS suggests that the national GHG reduction roadmap, coverage of GHG emitters and credibility of MRV positively affect GHG mitigation. However, there was a negative policy change implemented in 2017 that weakened the emission cap during the 1st phase. In terms of the Cost Effectiveness, the K-ETS policies related to market management and flexibility mechanism (e.g. banking, borrowing and offsets) were improved to deal with the liquidity shortage and permit price increase, which were caused by policy uncertainty and conservative behavior of firms during 2016-2018. Regarding Economic Efficiency, K-ETS expands benchmark?based allocation and began auction-based allocation; nevertheless, free allocation is being applied to sectors with high carbon leakage risk during the 2nd phase (2018-2020). As a result, it is worth evaluating the K-ETS policies that have been developed with respect to the three main objectives of ETS, considering the trial?and?error approach that has been followed since 2015. This study suggests that K-ETS policy should be modified to strengthen the emission cap, stabilize the market, expand auction-based allocation and build K-ETS specified funds during the 3rd phase (2021-2025).

• 한국철도학회논문집
• /
• 제7권3호
• /
• pp.251-258
• /
• 2004

A systematic methodology to determine safety requirements for railway signalling system and safety requirement allocation into system are presented. THR concept is used for as an interface between Risk Analysis to be performed by railway operator and System Design Analysis by the supplier. This approach is based on Signalling Safety Standard EN50129 by CENELEC.

• 한방안이비인후피부과학회지
• /
• 제30권2호
• /
• pp.1-18
• /
• 2017

Objectives : This review aims to evaluate a risk of bias by risk of bias tool and RoBANS(Risk of Bias Assessment tool for Non-randomized Study) tool for clinical trial papers proving treatment effect of Korean medicines to alopecia and provides the newest reason of effectiveness of herbs to alopecia. Methods : Data were collected through electronic database including NDSL, KISS, KMBASE, Koreantk, OASIS, KoreaMed, KISTI, Pubmed, Cochrane CENTRAL and CINAHL. Two experts in Oriental Medicine assessed risk of bias of randomized controlled trials by Cochrane group's Risk of Bias tool and non-randomized controlled trials by RoBANS tool after searching, reviewing and selecting papers. Results : Total number of selected trials is 20 including 4 randomized controlled trial, 13 non-randomized controlled trials and 3 case reports. This study evaluate the risk of bias of 17 papers including 4 randomized controlled trials and 13 non-randomized controlled trials except 3 case reports by risk of bias tool and RoBANS tool. All papers of randomized controlled trials are evaluated unclear for random sequence generation and allocation concealment as there are no word on them. And all papers of non-randomized controlled trials are evaluated unclear for blinding of outcome assessments and relatively low for others. Conclusions : Korean medicine intervention can be an effective for treatment in alopecia. It was evaluated by hair density, thickness and expert panel assessment of photographs and all results are statistically significant. But enhancing levels of evidence, we must try to reduce bias in researches and report a safety, protocol and IRB.

• Journal of information and communication convergence engineering
• /
• 제9권5호
• /
• pp.491-499
• /
• 2011

In this paper, we offer a new strategic portfolio model for national IT R&D project selection in Korea. A risk and return (R-R) portfolio model was developed using an objectively quantified index on the two axes of risk and return, in order to select a strategic project and allocate resources in compliance with a national IT R&D strategy. We strategize using the R-R portfolio model to solve the non-strategy and subjectivity problems of the existing national R&D project selection model. We also use the quantified evaluation index of the IT technology road map (TRM) and the technical level reports (TLR) for the subjectivity of project selection, and try to discover the weights using the analytic hierarchy process (AHP). In addition, we intend to maximize the chance for a successful national IT R&D project, by selecting a strategic portfolio project and balancing the allocation of resources effectively and objectively.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제18권1호
• /
• pp.30-45
• /
• 2024

This study introduces an effective method for predicting individual local tax delinquencies using prevalent machine learning and deep learning algorithms. The evaluation of credit risk holds great significance in the financial realm, impacting both companies and individuals. While credit risk prediction has been explored using statistical and machine learning techniques, their application to tax arrears prediction remains underexplored. We forecast individual local tax defaults in Republic of Korea using machine and deep learning algorithms, including convolutional neural networks (CNN), long short-term memory (LSTM), and sequence-to-sequence (seq2seq). Our model incorporates diverse credit and public information like loan history, delinquency records, credit card usage, and public taxation data, offering richer insights than prior studies. The results highlight the superior predictive accuracy of the CNN model. Anticipating local tax arrears more effectively could lead to efficient allocation of administrative resources. By leveraging advanced machine learning, this research offers a promising avenue for refining tax collection strategies and resource management.

• 대한전기학회논문지
• /
• 제41권1호
• /
• pp.9-17
• /
• 1992

Proper resource allocation is also a very important topic in power system problems, especially in operation and planning. One such is optimal maintenance problem in operation and planning. Least cost and highest reliability should be the subjects to be pursued. A probabilistic operation simulation model developed recently by authors is applied to the proboem of optimal maintenance scheduling. Three different methods are compared, marginal maintenance cost, levelized risk and maintenance space. The method by the marginal maintenance costs shows the least cost, the highest reliability and the highest maintenance outage rates. This latter characteristics may considerably influence the results of genetation planning, because the usual maintenance outages obtained from the other methods have shown to be lower.

• Journal of Preventive Medicine and Public Health
• /
• 제38권2호
• /
• pp.175-181
• /
• 2005

Objectives: This study estimated the burden of disease due to high alcohol consumption using DALY, a composite indicator recently developed by the Global Burden of Disease study group. The results were analyzed by age and sex. Methods: Firstly, high alcohol consumption-related diseases, and their relative risk (RR), were selected. Secondly, population attributable fractions (PAFs) were computed using formulae, including the relative risk (RR) and prevalence of exposure (Pe). Thirdly, the DALYs of high alcohol consumption-related diseases were estimated. Lastly, the attributable burdens of diseases due to high alcohol consumption wereconcluded as being the sum of the products that multiplied the DALYs of high alcohol consumption-related diseases by their population attributable fraction (PAF). Results : The burden of high alcohol consumption in Korea was 2992.3 person years (PYs) per 100,000 persons in men, and 1426.6 in women. For men, the high alcohol consumption-induced diseases with the five biggest burdens were liver cirrhosis, hypertensive disease, liver cancer, cerebral infarction and intracerebral hemorrhage. For women, these were cerebral infarction, intracerebral hemorrhage, hypertensive disease, liver cirrhosis and liver cancer. Conclusion: This study highlighted the attributable fraction of diseases due to exposure to high alcohol consumption, by quantifying the results of exposure to risk factors. Therefore, it is now possible to assess interventions for risk factors in quantifiable terms in each population. Finally, measuring the risk factor burdens was expected to contribute to priority setting and effective resource allocation in public health policy.