• Title/Summary/Keyword: Uncertainty

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Automation of Regression Analysis for Predicting Flatfish Production (광어 생산량 예측을 위한 회귀분석 자동화 시스템 구축)

  • Ahn, Jinhyun;Kang, Jungwoon;Kim, Mincheol;Park, So-Young
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2021.10a
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    • pp.128-130
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    • 2021
  • This study aims to implement a Regression Analysis system for predicting the appropriate production of flatfish. Due to Korea's signing of FTAs with countries around the world and accelerating market opening, Korean flatfish farming businesses are experiencing many difficulties due to the specificity and uncertainty of the environment. In addition, there is a need for a solution to problems such as sluggish consumption and price drop due to the recent surge in imported seafood such as salmon and yellowtail and changes in people's dietary habits. in this study, Using the python module, xlwings, it was used to obtain for the production amount of flatfish and to predict the amount of flatfish to be produced later. was used to predict the amount of flatfish to be produced in the future. Therefore, based on the analysis results of this prediction of flatfish production, the flatfish aquaculture industry will be able to come up with a plan to achieve an appropriate production volume and control supply and demand, which will reduce unnecessary economic loss and promote new value creation based on data. In addition, through the data approach attempted in this study, various analysis techniques such as artificial neural networks and multiple regression analysis can be used in future research in various fields, which will become the foundation of basic data that can effectively analyze and utilize big data in various industries.

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Quantitative analysis of hydrogen in thin film by scattering-recoil co-measurement technique (산란-되튐 동시 측정 방법에 의한 박막 중 수소 정량법)

  • Lee, Hwa-Ryun;Eum, Chul Hun;Choi, Han-Woo;Kim, Joonkon
    • Analytical Science and Technology
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    • v.19 no.5
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    • pp.400-406
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    • 2006
  • Hydrogen analysis by elastic recoil detection has been performed utilizing polyimide film as a reference sample of known hydrogen content assuming the soundness of ion beam current integration. However beam current integration at higher incidence angle is not reliable. Scattering yield per unit fluence by current integration which is normalized per unit path length decreases as the sample tilt angle is getting higher. Moreover because beam current integration at high tilt angle is incomplete, hydrogen evaluation is very risky by direct comparison of sequentially collected recoil spectra between reference and target sample. In this study, primary ion beam dose is determined by backscattering spectrum that is collected simultaneously with recoil spectrum instead of ion beam current integration in order to reduce uncertainty arising in the process of current integration and to enhance the reliability of quantitative analysis. Three test samples are selected $-7.6{\mu}m$ polyimide film, hydrogen implanted silicondioxide and Au deposited carbon wafer- and analyzed by two methods and compared.

Determination of bromine in 1000 ㎍/g Cl standard solution by ID-ICPMS (동위원소희석 질량분석법에 의한 1000 ㎍/g 염소 표준용액 중 브롬 불순물 분석)

  • Park, Chang Joon;Suh, Jung Kee;Song, Hyun Joo;Lee, Dong Soo
    • Analytical Science and Technology
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    • v.19 no.1
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    • pp.1-8
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    • 2006
  • The isotope dilution method was used for the determination of Br impurity in $1000{\mu}g/g$ Cl standard solution. Since relatively pure KCl salt was used for the preparation of the Cl standard solution, the Br impurity determination suffers from both spectral and non-spectral interferences due to the presence of a large amount of K and Cl matrices. AG2-X8 anion-exchange resin was employed to separate the Br analyte from the matrices, and RF power was raised to 1500 W and nebulizer gas flow rate was lowered to 0.77 L/min to reduce background from the $ArArH^+$ molecular ions. The Br impurity in the $1000{\mu}g/g$ Cl standard solution was determined to be 43.7 ng/g with the standard addition method. The analytical result was in good agreement with 41.2 ng/g (RSD 1.6%) determined by the isotope dilution method to lower uncertainty from poor reproducibility of the anion-exchange process.

Determination of trace arsenic in seawater by flow injection-hydride generation inductively coupled plasma mass spectrometry (연속흐름주입-수소화물생성-유도결합플라스마 질량분석장치를 이용한 바닷물표준시료중의 극미량 비소분석방법의 확립)

  • Suh, Jung-Ki
    • Analytical Science and Technology
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    • v.21 no.4
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    • pp.316-325
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    • 2008
  • An inductively coupled plasma mass spectrometry (ICP-MS) instrument equipped with flow injection-hydride generation system was used for the determination of trace arsenic in seawater sample. The accuracy in this method was verified by the analysis of certified reference materials (CRM) of seawater (CASS-4, NASS-5). The analytical results agreed with certified value within the range of uncertainty. The expanded uncertainties for CASS-4 and NASS-5 in this experiment were ranged from 6.2% to 6.8% obtained from repeated analyses of the CRMs (n=5). The detection limit of $As^+$ (m/z=74.9216) in this method was confirmed about 0.01 ug/kg. Linearity obtained from calibration curve of arsenic was excellent ($R^2=1$). The detection at $As^+$ (m/z=74.9216) and $AsO^+$ (m/z=90.9165) by using oxygen reaction gas in DRC mode was compared. Sensitivity at $AsO^+$ (m/z=90.9165) was decreased about 25-fold, but the analytical results are the same that at $As^+$ (m/z=74.9216).

Drought Frequency Analysis Using Cluster Analysis and Bivariate Probability Distribution (군집분석과 이변량 확률분포를 이용한 가뭄빈도해석)

  • Yoo, Ji Young;Kim, Tae-Woong;Kim, Sangdan
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.6B
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    • pp.599-606
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    • 2010
  • Due to the short period of precipitation data in Korea, the uncertainty of drought analysis is inevitable from a point frequency analysis. So it is desired to introduce a regional drought frequency analysis. This study first extracted drought characteristics from 3-month and 12-month moving average rainfalls which represent short and long-term droughts, respectively. Then, the homogeneous regions were distinguished by performing a principal component analysis and cluster analysis. The Korean peninsula was classified into five regions based on drought characteristics. Finally, this study applied the bivariate frequency analysis using a kernel density function to quantify the regionalized drought characteristics. Based on the bivariate drought frequency curves, the drought severities of five regions were evaluated for durations of 2, 5, 10, and 20 months, and return periods of 5, 10, 20, 50, and 100 years. As a result, the largest severity of drought was occurred in the Lower Geum River basin, in the Youngsan River basin, and over in the southern coast of Korea.

Quantitative Deterioration and Maintenance Profiles of Typical Steel Bridges based on Response Surface Method (응답면 기법을 이용한 강교의 열화 및 보수보강 정량화 이력 모델)

  • Park, Seung-Hyun;Park, Kyung Hoon;Kim, Hee Joong;Kong, Jung-Sik
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.6A
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    • pp.765-778
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    • 2008
  • Performance Profiles are essential to predict the performance variation over time for the bridge management system (BMS) based on risk management. In general, condition profiles based on experts opinion and/or visual inspection records have been used widely because obtaining profiles based on real performance is not easy. However, those condition profiles usually don't give a good consistency to the safety of bridges, causing practical problems for the effective bridge management. The accuracy of performance evaluation is directly related to the accuracy of BMS. The reliability of the evaluation is important to produce the optimal solution for distributing maintenance budget reasonably. However, conventional methods of bridge assessment are not suitable for a more sophisticated decision making procedure. In this study, a method to compute quantitative performance profiles has been proposed to overcome the limitations of those conventional models. In Bridge Management Systems, the main role of performance profiles is to compute and predict the performance of bridges subject to lifetime activities with uncertainty. Therefore, the computation time for obtaining an optimal maintenance scenario is closely related to the efficiency of the performance profile. In this study, the Response Surface Method (RSM) based on independent and important design variables is developed for the rapid computation. Steel box bridges have been investigated because the number of independent design variables can be reduced significantly due to the high dependency between design variables.

The Relationship between Enterance Exam Stress and Oral Care Self-Efficacy in 3rd year Girl High School Students (인문계 3학년 여자 고등학생의 입시스트레스와 구강관리 자기효능감과의 관련성)

  • Cho, Hye-Eun;Chung, Kyung-Yi
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.8
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    • pp.551-561
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    • 2019
  • The purpose of this study was to investigate the relationship between entrance exam stress and oral care self-efficacy in girls high school. From June to July 2018, A self-reported questionnaire was administered to 192 high school students in the G area. The data were analyzed for independent t-test, one-way ANOVA and Pearson's correlation coefficient by using SPSS/WIN 21.0 program. Among the sub-sectors of entrance exam stress, exam tension/poor was the highest with 3.07 points, followed by Insufficient spare time stress 2.83 points, future uncertainty stress 2.57 points, and parent pressure stress 2.44 points. the variables related to exam tension/poor stress were academic performance (p<.01), family income level (p<.05), Subjective oral health status(p<.05), and daily brushing frequency(p<.01). The highest level of oral care self-efficacy was 3.13 points for brushing self-efficacy, followed by dental visits 2.80 points and interdental hygiene 2.64 points. As a result of analyzing the general characteristics and oral care self-efficacy, subjects related to brushing self-efficacy were subjective oral health status, caries snacking(daily), and caries drinks(daily)(p<.01). There were negative correlations between entrance exam stress and oral care self-efficacy. The higher the entrance stress, the lower the oral care self-efficacy. To prevent oral disease and increase oral care self-efficacy of students with high entrance stress, it is necessary to provide school oral health education programs that can facilitate oral health behaviors.

An Examination of the Effectiveness of Crisis Response Strategies for Repairing Competence and Integrity Violations

  • Sung, Yen-yi;Lee, Han-joon;Park, Jong-chul
    • Asia Marketing Journal
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    • v.15 no.1
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    • pp.129-154
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    • 2013
  • Product-harm crises, which are connected to defective or dangerous products, are perceived as the most common threats to a company. Product harm crises can distort long standing favorable equality perceptions, tarnish a company's reputation, cause major revenue and market-share losses, lead to costly product recalls, and devastate a carefully nurtured brand equity. However, in spite of the devastating impact of product-harm crises, little systematic research exists to asses its marketing consequences. So, the purpose of this study is to investigate how Koreans react to the crisis response in the aftermath of different crises(competence violation vs. integrity violation) and inspire additional research in crisis communication. This study has three main findings which run counter to the assumptions of Kim et al.(2007). Namely, the current study expands on the research of Kim et al. (2004, 2007) by examining how companies repair customers' trust and corporate attitude after crises. Different from previous studies, this study assumes that apology for an integrity-based crisis is the most appropriate way to repair consumer trust and corporate attitude. As for competence-based crisis, similarly, apology for competence-based crisis can be more successful repairing consumer trust and corporate attitude. Concerning silence strategy, remaining silent dose not admit or deny guilt right away, but instead of asking the perceiver to withhold judgment, suggesting that, silence could be expected to be superior to apology but inferior to denial. Finally, apology for competence violation will be expected to bemore effective than apology for integrity violation. Research conceptual model was as follows: According to the results, apology is found to be the most effective strategy to repair corporate attitude no matter the crisis is perceived as a violation of competence or integrity. Second, company may consider keeping silent as a desirable response because they does not admit nor deny responsibility but ask the public to withhold judgment. However, the result of this study shows that, in the overall crisis situations, silence strategy did not differ significantly from the denial strategy, which suggested that the public wants explanation instead of uncertainty. Third, there was the interaction effect between crisis type and crisis response strategies. In this study, apology is more effective for the competence violated situation in terms of regaining consumer trust and repairing their attitude toward company, while the apology's effectiveness is lower for the integrity-violated situation. More specifically, when the crisis is perceived due to company's lack of ability(competence violation), consumer's trust belief and attitude toward the company is more easily to repair when the company issued a sincere apology. Damaged product is perceived less intentional so participants are more likely to give the company second chance when they apology to the public. By contrast, exaggerated advertisement(integrity violation) is perceived intentionally and thus makes participants angrier toward the accused company. Although apology is perceived as the most effective strategy, when issuing apology, it also means the company admitted their intention. Therefore, in this kind of crisis situation, trust repair needs not only a sincere apology but additional efforts.

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Informative Role of Marketing Activity in Financial Market: Evidence from Analysts' Forecast Dispersion

  • Oh, Yun Kyung
    • Asia Marketing Journal
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    • v.15 no.3
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    • pp.53-77
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    • 2013
  • As advertising and promotions are categorized as operating expenses, managers tend to reduce marketing budget to improve their short term profitability. Gauging the value and accountability of marketing spending is therefore considered as a major research priority in marketing. To respond this call, recent studies have documented that financial market reacts positively to a firm's marketing activity or marketing related outcomes such as brand equity and customer satisfaction. However, prior studies focus on the relation of marketing variable and financial market variables. This study suggests a channel about how marketing activity increases firm valuation. Specifically, we propose that a firm's marketing activity increases the level of the firm's product market information and thereby the dispersion in financial analysts' earnings forecasts decreases. With less uncertainty about the firm's future prospect, the firm's managers and shareholders have less information asymmetry, which reduces the firm's cost of capital and thereby increases the valuation of the firm. To our knowledge, this is the first paper to examine how informational benefits can mediate the effect of marketing activity on firm value. To test whether marketing activity contributes to increase in firm value by mitigating information asymmetry, this study employs a longitudinal data which contains 12,824 firm-year observations with 2,337 distinct firms from 1981 to 2006. Firm value is measured by Tobin's Q and one-year-ahead buy-and-hold abnormal return (BHAR). Following prior literature, dispersion in analysts' earnings forecasts is used as a proxy for the information gap between management and shareholders. For model specification, to identify mediating effect, the three-step regression approach is adopted. All models are estimated using Markov chain Monte Carlo (MCMC) methods to test the statistical significance of the mediating effect. The analysis shows that marketing intensity has a significant negative relationship with dispersion in analysts' earnings forecasts. After including the mediator variable about analyst dispersion, the effect of marketing intensity on firm value drops from 1.199 (p < .01) to 1.130 (p < .01) in Tobin's Q model and the same effect drops from .192 (p < .01) to .188 (p < .01) in BHAR model. The results suggest that analysts' forecast dispersion partially accounts for the positive effect of marketing on firm valuation. Additionally, the same analysis was conducted with an alternative dependent variable (forecast accuracy) and a marketing metric (advertising intensity). The analysis supports the robustness of the main results. In sum, the results provide empirical evidence that marketing activity can increase shareholder value by mitigating problem of information asymmetry in the capital market. The findings have important implications for managers. First, managers should be cognizant of the role of marketing activity in providing information to the financial market as well as to the consumer market. Thus, managers should take into account investors' reaction when they design marketing communication messages for reducing the cost of capital. Second, this study shows a channel on how marketing creates shareholder value and highlights the accountability of marketing. In addition to the direct impact of marketing on firm value, an indirect channel by reducing information asymmetry should be considered. Potentially, marketing managers can justify their spending from the perspective of increasing long-term shareholder value.

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Research on optimal safety ship-route based on artificial intelligence analysis using marine environment prediction (해양환경 예측정보를 활용한 인공지능 분석 기반의 최적 안전항로 연구)

  • Dae-yaoung Eeom;Bang-hee Lee
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2023.05a
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    • pp.100-103
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    • 2023
  • Recently, development of maritime autonomoust surface ships and eco-friendly ships, production and evaluation research considering various marine environments is needed in the field of optimal routes as the demand for accurate and detailed real-time marine environment prediction information expands. An algorithm that can calculate the optimal route while reducing the risk of the marine environment and uncertainty in energy consumption in smart ships was developed in 2 stages. In the first stage, a profile was created by combining marine environmental information with ship location and status information within the Automatic Ship Identification System(AIS). In the second stage, a model was developed that could define the marine environment energy map using the configured profile results, A regression equation was generated by applying Random Forest among machine learning techniques to reflect about 600,000 data. The Random Forest coefficient of determination (R2) was 0.89, showing very high reliability. The Dijikstra shortest path algorithm was applied to the marine environment prediction at June 1 to 3, 2021, and to calculate the optimal safety route and express it on the map. The route calculated by the random forest regression model was streamlined, and the route was derived considering the state of the marine environment prediction information. The concept of route calculation based on real-time marine environment prediction information in this study is expected to be able to calculate a realistic and safe route that reflects the movement tendency of ships, and to be expanded to a range of economic, safety, and eco-friendliness evaluation models in the future.

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