• Title/Summary/Keyword: Estimation Methodology

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Development of human-in-the-loop experiment system to extract evacuation behavioral features: A case of evacuees in nuclear emergencies

  • Younghee Park;Soohyung Park;Jeongsik Kim;Byoung-jik Kim;Namhun Kim
    • Nuclear Engineering and Technology
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    • v.55 no.6
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    • pp.2246-2255
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    • 2023
  • Evacuation time estimation (ETE) is crucial for the effective implementation of resident protection measures as well as planning, owing to its applicability to nuclear emergencies. However, as confirmed in the Fukushima case, the ETE performed by nuclear operators does not reflect behavioral features, exposing thus, gaps that are likely to appear in real-world situations. Existing research methods including surveys and interviews have limitations in extracting highly feasible behavioral features. To overcome these limitations, we propose a VR-based immersive experiment system. The VR system realistically simulates nuclear emergencies by structuring existing disasters and human decision processes in response to the disasters. Evacuation behavioral features were quantitatively extracted through the proposed experiment system, and this system was systematically verified by statistical analysis and a comparative study of experimental results based on previous research. In addition, as part of future work, an application method that can simulate multi-level evacuation dynamics was proposed. The proposed experiment system is significant in presenting an innovative methodology for quantitatively extracting human behavioral features that have not been comprehensively studied in evacuation. It is expected that more realistic evacuation behavioral features can be collected through additional experiments and studies of various evacuation factors in the future.

Adaptive Milling Process Modeling and Nerual Networks Applied to Tool Wear Monitoring (밀링공정의 적응모델링과 공구마모 검출을 위한 신경회로망의 적용)

  • Ko, Tae-Jo;Cho, Dong-Woo
    • Journal of the Korean Society for Precision Engineering
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    • v.11 no.1
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    • pp.138-149
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    • 1994
  • This paper introduces a new monitoring technique which utilizes an adaptive signal processing for feature generation, coupled with a multilayered merual network for pattern recognition. The cutting force signal in face milling operation was modeled by a low order discrete autoregressive model, shere parameters were estimated recursively at each sampling instant using a parameter adaptation algorithm based on an RLS(recursive least square) method with discounted measurements. The influences of the adaptation algorithm parameters as well as some considerations for modeling on the estimation results are discussed. The sensitivity of the extimated model parameters to the tool state(new and worn tool)is presented, and the application of a multilayered neural network to tool state monitoring using the previously generated features is also demonstrated with a high success rate. The methodology turned out to be quite suitable for in-process tool wear monitoring in the sense that the model parameters are effective as tool state features in milling operation and that the classifier successfully maps the sensors data to correct output decision.

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Born Global Strategies and the Corporate Performance of Korean Firms

  • Che-Yung Kang;Min-Ho Kim
    • Journal of Korea Trade
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    • v.27 no.1
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    • pp.159-175
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    • 2023
  • Purpose - This paper empirically investigates the relationship between born global strategy and the accounting- and market- based financial performance of Korean firms. Further, this study identifies the characteristics of born global firms (BGs) in comparison with non-BG counterparts in terms of size, R&D, and liability. Design/methodology - Using a database of listed Korean SMEs in the manufacturing sector from 2010 to 2020, this study applies panel generalized least squares (GLS) estimation and logistic regression techniques. Findings - This study finds that BG strategy is negatively related to the firm's accounting-based financial performance, while it is positively related to the market-based financial performance. This study also finds that BGs have higher sales volume and more total assets compared to their non-BG counterparts. In addition, Korean BGs spend more on R&D, and at the same time have higher liability. Originality/value - BGs, by definition, are firms that are actively penetrating foreign markets from the early stages of their establishment. Previous studies of Korean BGs have tried to identify the determinants of BGs' rapid internationalization and their superior performance. However, most of these studies have utilized either qualitative case- or survey-based analyses with relatively limited numbers of observations. From a different perspective, this study provides more objective evidence by investigating how the BG strategy affects the financial and market performance of firms, and by characterizing BGs in terms of financial data.

An Effect of Volatility of Crude Oil Price on Asymmetry of Domestic Gasoline Price Adjustment (국제 유가 변동성이 국내 휘발유 가격 비대칭성에 미치는 영향)

  • Nam-Jae Kim;Hyung-Gun Kim
    • Asia-Pacific Journal of Business
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    • v.14 no.1
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    • pp.351-364
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    • 2023
  • Purpose - This study examines the effects of Dubai oil price and the volatility on the asymmetry of domestic gasoline price adjustment. Additionally, the study investigates the effects of "Altteul" gas-station and tax-cut policies on asymmetry. Design/methodology/approach - Firstly, the study calculates proxies for asymmetry and volatility of each window(every 3-month) by error-correction model and GARCH(1, 1) using daily domestic gas price and Dubai oil price from 2008/04/15 to 2022/12/31. Secondly, the study investigates the effects of the increasing rate of Dubai oil price, volatility, "Altteul" gas-station and tax-cut policies on asymmetry. The autoregressive distributed lag regression model is employed for estimations. Findings - The study finds that changes in the increasing rate of Dubai oil price and both types of volatility of Dubai oil price increase asymmetry. While "Altteul" gas-station and tax-cut policies decrease asymmetry. Additionally, the study fails to find that asymmetry in the Korean gasoline market in the estimation with total observations. Research implications or Originality - An increase in Dubai oil price volatility means an increase in cost uncertainty for gas-station owners. Since cost uncertainty is a kind of financial risk, the increase in volatility reinforces the asymmetry. The study provides supporting evidence for the idea.

An Investigation on the Mutual Effect between Tax Revenue and Economic Growth

  • He, Yugang
    • The Journal of Economics, Marketing and Management
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    • v.6 no.3
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    • pp.14-25
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    • 2018
  • Purpose - Taxes cover all aspects of society, especially in terms of resource allocation and economic growth. In reality, the tax revenue is often used to measure the quality of a country's economy. The relationship between tax revenue and economic growth has been paid much attention by academic circles. Due to this background, this paper attempts to investigate the mutual effect between tax revenue and economic growth. Research design, data, and Methodology - The annual datum form 1980 to 2017 are employed to conduct an empirical analysis under the vector error correction model. In this paper, the GDP is treated as an independent variable. The tax revenue is treated as a dependent variable. Furthermore, a menu of statistic approaches will be used to testify the mutual effect between tax revenue and economic growth. Results - Via the co-integration test, the results report that the tax revenue has a positive effect on economic growth in the long run. Through the vector error correction estimation, the results also report that the tax revenue also has a positive effect on economic growth in the short run. Conclusions - This paper provides a view that the tax revenue is a kind of a determinant to promote economic growth. Therefore, the China's government should pay much attention to the improvement of tax revenue system so as to maintain a high-speed economic growth.

Analysis of Local Tax Performance Through Tax Capacity and Tax Effort in Indonesia 2014-2018

  • RAFSANJANI, Ali Hadi;AGUSTINA, Neli
    • Asian Journal of Business Environment
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    • v.12 no.2
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    • pp.43-53
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    • 2022
  • Purpose: This study aims to analyze the performance of local taxes in Indonesia through the estimation of tax capacity and tax effort, as well as classifying provinces based on the estimated value of tax capacity and tax effort. Research design, data and methodology: this study uses panel data of 34 provinces in Indonesia for the period of 2014-2018. The analytical method used in the tax capacity model is panel data regression to explain the factors that influence tax performance. Tax effort is estimated by the ratio of tax to tax capacity. Results: The results of the analysis show that gini ratio and regional expenditures have a significant positive effect on the tax ratio, while the share of GRDP in the manufacturing sector and HDI has a significant negative effect on the tax ratio. Based on the results, there are 19 provinces that have low tax capacity and 16 provinces that have low tax effort. Conclusions: The development of local tax performance tends to fluctuate with an average of 1.24 percent per year. Gini ratio and regional expenditure have a significant positive effect on the tax ratio, while the share of GRDP in the manufacturing sector and HDI have a significant negative effect on the tax ratio.

Development of a Methodology for Estimating Radioactivity Concentration of NORM Scale in Scrap Pipes Based on MCNP Simulation

  • Wanook Ji;Yoomi Choi;Zu-Hee Woo;Young-Yong Ji
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.21 no.4
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    • pp.481-487
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    • 2023
  • Concerning the apprehensions about naturally occurring radioactive materials (NORM) residues, the International Atomic Energy Agency (IAEA) and its member nations have acknowledged the imperative to ensure the radiation safety of NORM industries. Residues with elevated radioactivity concentrations are predominantly produced during NORM processing, in the form of scale and sludge, referred to as technically enhanced NORM (TENORM). Substantial quantities of TENORM residues have been released externally due to the dismantling of NORM processing factories. These residues become concentrated and fixed in scale inside scrap pipes. To assess the radioactivity of scales in pipes of various shapes, a Monte Carlo simulation was employed to determine dose rates corresponding to the action level in TENORM regulations for different pipe diameters and thicknesses. Onsite gamma spectrometry was conducted on a scrap iron pipe from the titanium dioxide manufacturing factory. The measured dose rate on the pipe enabled the estimation of NORM concentration in the pipe scale onsite. The derived action level in dose rate can be applied in the NORM regulation procedure for on-site judgments.

A Study on the Estimation of Required Seaborne Trade Volume and Carrier Volume of Each Vessel Type in Case of Emergency (우리나라 비상사태시 소요물동량 및 선종별 소요선대 추정 연구)

  • Young-Gyun Ahn
    • Korea Trade Review
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    • v.45 no.1
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    • pp.1-11
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    • 2020
  • The maritime industry is important for Korean international trade, as more than 99 percent of its imports and exports are moved by maritime transportation. However, if maritime transportation is stopped in the event of an emergency, such as war or natural disaster, there is a danger that imports and exports may cease abruptly. Coping with this risk is why the Ministry of Oceans and Fisheries, manages the 'National Necessary Shipping System.' This system requires that the government estimates the size of ships necessary in the case of an emergency, and the ships designated as National Necessary Vessels should transport goods in the case of actual emergencies. This study seeks to estimate the appropriate size of ships required in an emergency using the latest data and applying a quantitative methodology. This study provides useful reference materials for policy authorities. In particular, it is meaningful that this study estimates the required number of ships of each vessel type, reflecting the recent trend of large-scale ships and expanding global trade.

A Study on the Perception and Evaluation of the Socioeconomic Value of the Agricultural Income Survey (농산물소득조사의 사회경제적 가치 인식 및 평가에 관한 연구)

  • Lee, Choon-Soo;Jung, Da-Eun;Yang, Sung-Bum
    • Korean Journal of Organic Agriculture
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    • v.31 no.4
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    • pp.259-289
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    • 2023
  • This study analyzed farmers' and experts' perceptions of the Agricultural Income Survey (AIS) conducted by the Rural Development Administration and estimated its socioeconomic value. The research surveyed 104 farmers in Gyeongsangbuk-do and Jeollanam-do. To estimate the AIS's socioeconomic value, this study examined public information projects in the field of agriculture and public information, proposing an estimation methodology based on prior research. The socioeconomic value of the AIS was calculated in three stages (information generation, collection and analysis, and utilization) using the replacement cost and contingent valuation methods. In 2020, the estimated socioeconomic value of the AIS ranged from a minimum of KRW 631.2 billion to a maximum of KRW 799.1 billion per year. To improve the socioeconomic value of the AIS, it is important to booster awareness, expand sample sizes for more reliable data, increase manpower and budget, refine survey questions, and enhance analyzing capabilities. And it's crucial to foster cooperation with surveyed farms, promote collaboration among investigative agencies, improve investigator skills, and strengthen management capabilities to facilitate information dissemination.

A Human-Centric Approach for Smart Manufacturing Adoption: An Empirical Study

  • Ying PAN;Aidi AHMI;Raja Haslinda RAJA MOHD ALI
    • Journal of Distribution Science
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    • v.22 no.1
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    • pp.37-46
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    • 2024
  • Purpose: This study aims to address the overlooked micro-level aspects within Smart Manufacturing (SM) research, rectifying the misalignment in manufacturing firms' estimation of their technological adoption capabilities. Drawing upon the Social-Technical Systems (STS) theory, this paper utilises innovation capability as a mediating variable, constructing a human-centric organizational model to bridge this research gap. Research design, data and methodology: This study collected data from 233 Chinese manufacturing firms via online questionnaires. Introducing innovation capability as a mediating variable, it investigates the impact of social-technical system dimensions (work design, social subsystems, and technical subsystems) on SM adoption willingness. Smart PLS 4.0 was employed for data analysis, and Structural Equation Modelling (SEM) validated the theoretical model's assumptions. Results: In direct relationships, social subsystems, technical subsystems, and work design positively influence firms' innovation capabilities, which, in turn, positively impact SM adoption. However, innovation capability does not mediate the relationship between technical subsystems and SM adoption. Conclusions: This study focuses on the internal micro-level of organisational employees, constructing a human-centric framework that emphasises the interaction between organisations and technology. The study fills empirical gaps in Smart Manufacturing adoption, providing organisations with a means to examine the integration of employees and the organisational social-technical system.