• Journal of Korean Society on Water Environment
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• v.29 no.5
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• pp.681-690
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• 2013

Watershed models have been increasingly used to support an integrated management of land and water, non-point source pollutants, and implement total daily maximum load policy. However, these models demand a great amount of input data, process parameters, a proper calibration, and sometimes result in significant uncertainty in the simulation results. For this reason, uncertainty analysis is necessary to minimize the risk in the use of the models for an important decision making. The objectives of this study were to evaluate three different uncertainty analysis algorithms (SUFI-2: Sequential Uncertainty Fitting-Ver.2, GLUE: Generalized Likelihood Uncertainty Estimation, ParaSol: Parameter Solution) that used to analyze the sensitivity of the SWAT(Soil and Water Assessment Tool) parameters and auto-calibration in a watershed, evaluate the uncertainties on the simulations of runoff and sediment load, and suggest alternatives to reduce the uncertainty. The results confirmed that the parameters which are most sensitive to runoff and sediment simulations were consistent in three algorithms although the order of importance is slightly different. In addition, there was no significant difference in the performance of auto-calibration results for runoff simulations. On the other hand, sediment calibration results showed less modeling efficiency compared to runoff simulations, which is probably due to the lack of measurement data. It is obvious that the parameter uncertainty in the sediment simulation is much grater than that in the runoff simulation. To decrease the uncertainty of SWAT simulations, it is recommended to estimate feasible ranges of model parameters, and obtain sufficient and reliable measurement data for the study site.

• The Korean Journal of Franchise Management
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• v.12 no.1
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• pp.35-44
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• 2021

Purpose: This study examines the opportunism moderating effect by the startup experience in the relationship between franchisor and franchisees. In the case of a franchise system that has a continuous relational exchange transaction, relationship management is a very important activity because the relationship management between franchisor and franchisees improves the quality of the relationship. Nevertheless, there is insufficient of research on opportunism, which is a negative factor in managing the relationship between franchisor and franchisees in continuous relationship. Research design, data and methodology: This study, we explore the cause of opportunism based on transaction cost theory through prior research and establish a research model based by goal incongruity, uncertainty, information asymmetry, transaction specific assets, the relevance to determinant of opportunism and the startup experienced which is a moderating variable. To verify several hypotheses, the data were collected from 300 out of 1,760 domestic franchisees and analyzed using multiple regression analysis with SPSS program. Results: The findings are as follows. Goal incongruity did not affect opportunism. Opportunism increased as uncertainty increased, and as information asymmetry increased, opportunism increased. An opportunism decreased as transaction specific assets increased. Moreover, the findings show that startup experience only plays a moderating role in the relationship between information asymmetry and opportunism. Therefore, 4 out of 8 hypotheses were supported. Conclusions: The findings show that uncertainty, information asymmetry, and transaction specific assets are the determinants of opportunism. In addition, the results of the analysis of the moderating role of startup experience show that the less entrepreneurial experience, the greater the influence of information asymmetry on opportunism. Our findings mean that maintaining a successful relationship between franchisors and franchisees is possible when franchisors provide knowledge sharing, goal sharing, environmental sharing, and management information sharing to franchisees. In addition, the findings of this study shows that the contract content and management should be changed according to the entrepreneurial experience. In other words, the franchisors must share and integrate the accumulated franchisees' and franchisors' experience with the franchisees to create a synergy that can lead to successful bilateral relationship maintenance, which in turn reduces opportunism.

• Journal of muscle and joint health
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• v.22 no.1
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• pp.48-56
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• 2015

Purpose: The purpose of this study was to verify the effects of visual information on nursing management to elderly total knee arthroplasty (TKA) patients. Methods: A quasi-experimental study with a non-equivalent control group pretest-posttest design was used in this study. Participants of this study were 60 elderly patients with TKA admitted to one hospital: the control group (30) between July and September, 2013, and the experimental group (30) between April and July, 2013. Anxiety and uncertainty were determined at baseline and at 3 days after TKA in both groups. Results: Two days after the visual information, the experimental group showed a significant decrease in anxiety and uncertainty compared with the control group. Conclusion: The results of this study show that providing visual information was effective in decreasing postoperative patient anxiety and uncertainty in elderly TKA patients. Therefore, when an elderly patient is hospitalized for TKA, positive and systematic provision of visual information may provide a positive effect by reducing postoperative patient anxiety and uncertainty.

• YAKHAK HOEJI
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• v.51 no.3
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• pp.206-213
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• 2007

Recently estimating the uncertainty of an analytical result has become an essential part of quantitative analysis. This study describes the uncertainty of the measurement for the determination of methamphetamine and its major metabolite amphetamine in human hair, The method consists of washing, drying, weighing, incubation and extraction with methanolic HCI solution, clean-up, trifluoroacetyl derivatization, and qualification/quantification of residues by gas chromatography/mass spectrometry (GC/MS). Traceability of measurement was established through traceable standards and calibrated volumetric equipment and measuring instruments. Measurement uncertainty associated with each analyte in real samples was estimated using quality control (QC) data. The main source of combined standard uncertainty comprised two components, which are uncertainties associated with calibration linearity and variations in QC, while those associated with preparation of analytical standards and sample weighing were not so important considering the degree of contribution. Relative combined standard uncertainties associated with the described method ranged for individual analytes from 4.99 to5.03%.

• The Journal of Industrial Distribution & Business
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• v.13 no.9
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• pp.11-26
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• 2022

Purpose: Manufacturers rely on interfirm governance mechanisms to reduce the risks inherent in uncertain environments; however, it is unclear which governance mechanisms are developed to manage relationships with suppliers. This study sought to enhance knowledge of how environmental uncertainty affects interfirm governance mechanisms under conditions reflecting varying levels of structural holes. To this end, the study investigated the relationships between manufacturers and major first-tier and sub-suppliers. In particular, the moderating effect of structural holes is examined. Research design, data and methodology: A questionnaire survey was conducted with a major first-tier supplier of a Korean engineering firm. Proposed hypotheses were tested using structural equation modeling. Results: The results show that while the relationship between environmental uncertainty and unilateral governance is positive but statistically insignificant, with bilateral governance is negative and statistically significant. The study also demonstrates that when structural holes are considered, the effects between environmental uncertainty and governance mechanisms are attenuated. Conclusions: This study suggests some theoretical and managerial contributions between exchange partners, especially, the results suggest that structural holes have a critical competitive advantage in uncertain environments. Therefore, manufacturers should carefully consider how they deal with environmental uncertainty when they make a business decision under structural holes situations.

• Asia-Pacific Journal of Business
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• v.12 no.4
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• pp.63-86
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• 2021

Purpose - The purpose of this study is to explore the impact of the application of accounting conservatism on the investment efficiency of listed companies in China under the background of the current rising environmental uncertainty. Design/methodology/approach - This study collected 14,934 observations of A-share listed companies in Shanghai and Shenzhen from 2013 to 2020, and analyzed the data by means of moderating effect test and multiple regression analysis. Findings - The results show that environmental uncertainty deteriorates the company's investment efficiency. The higher the level of environmental uncertainty, the more prone to over-investment and under-investment. Accounting conservatism plays moderating role between environmental uncertainty and investment efficiency. Among them, the moderating effect of conditional conservatism is to alleviate under-investment of the company under high financing constraints and the over-investment, while it intensifies the under-investment under low financing constraints. The moderating effect of unconditional conservatism is to alleviate the under-investment. Research implications or Originality - This study finds out the internal mechanism of accounting conservatism affecting investment efficiency, which not only helps to understand about the value of accounting conservatism standards, but also helps to improve the investment efficiency of listed companies.

• Journal of Home Health Care Nursing
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• v.30 no.1
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• pp.84-95
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• 2023

Purpose: This study aimed to clarify the concept of uncertainty in brain tumor patients. Methods: We used the Walker and Avant's concept analysis method. We searched RISS, MEDLINE, CINAHL, and EMBASE for published articles in Korean and English from January 2002 to December 2022. After applying the inclusion and exclusion criteria, 27 articles were selected for the final analysis. Result: "Uncertainty in brain tumor" was defined as a state in which related clues during the process of experiencing a disease after brain tumor diagnosis are unclear or difficult to understand, new experiences different from before, or a condition in which it is difficult to judge fragmentarily. Moreover, the empirical criteria for the attributes of uncertainty in brain tumor patients were ambiguity of the disease process, diversity of information, unpredictability of prognosis, and complexity of management. Conclusion: Brain tumor patients with uncertainty require strategic technology development so that brain tumor patients, their families, and health care providers can use reasonable coping methods.

• Journal of the Korean Society of Safety
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• v.39 no.3
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• pp.75-83
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• 2024

Accurately assessing and managing risks in any endeavor is crucial. Risk assessment in engineering translates the abstract concept of risk into actionable strategies for systematic risk management. However, risk validation is met with significant skepticism, particularly concerning the uncertainty of probability. This study aims to address the aforementioned uncertainty in a multitude of ways. Firstly, instead of relying on deterministic probability, it acknowledges uncertainty and presents a probabilistic interval. Secondly, considering the uncertainty interval highlighted in OREDA, it delineates the bounds of the probabilistic interval. Lastly, it investigates how much explanatory power deterministic probability has within the defined probabilistic interval. By utilizing fault tree analysis (FTA) and integrating confidence intervals, a probabilistic risk assessment was conducted to scrutinize the explanatory power of deterministic probability. In this context, explanatory power signifies the proportion of probability within the probabilistic risk assessment interval that lies below the deterministic probability. Research results reveal that at a 90% confidence interval, the explanatory power of deterministic probability decreases to 73%. Additionally, it was confirmed that explanatory power reached 100% only with a probability application 36.9 times higher.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.257-260
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• 2001

Buffers, on which much research is being done, are being used as a means to alleviate impacts in processes. Impacts occur from variation which is caused by uncertainty. Current buffers just accept variation as it comes and have just been used as a means to reduce impact. The purpose of this research try to understand the assorted variations which arise from limited resources and information and then we present a division of buffers as the way to overcome these variations. Through the process of dividing buffers into screening buffers, pulling buffers, shielding buffers, and working buffers, we try to make the process more compact, eliminate unnecessary reduction, speed up the decision making process by excluding excessive information, and improve the reliability of work.

• Nuclear Engineering and Technology
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• v.53 no.2
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• pp.484-497
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• 2021

This paper proposes an extended time uncertainty analysis approach in Level 2 human reliability analysis (HRA) considering severe accident management (SAM) strategies. The method is a time-based model that classifies two time distribution functions-time required and time available-to calculate human failure probabilities from delayed action when implementing SAM strategies. The time required function can be obtained by the combination of four time factors: 1) time for diagnosis and decision by the technical support center (TSC) for a given strategy, 2) time for strategy implementation mainly by the local emergency response organization (ERO), 3) time to verify the effectiveness of the strategy and 4) time for portable equipment transport and installation. This function can vary depending on the given scenario and includes a summation of lognormal distributions and a choice regarding shifting the distribution. The time available function can be obtained via thermal-hydraulic code simulation (MAAP 5.03). The proposed approach was applied to assess SAM strategies that use portable equipment and safety depressurization system valves in a total loss of component cooling water event that could cause reactor vessel failure. The results from the proposed method are more realistic (i.e., not conservative) than other existing methods in evaluating SAM strategies involving the use of portable equipment.