• Title/Summary/Keyword: structure changes

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Effect of environmental conditions on the stock structure and abundance of the Pacific saury, Cololabis saira in the Tsushima Warm Current region (대마난류계 꽁치의 자원구조와 풍도에 미치는 해양환경의 영향)

  • Gong, Yeong;Seo, Yeong-Sang
    • Journal of Environmental Science International
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    • v.13 no.5
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    • pp.449-467
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    • 2004
  • Interannual and decadal scale changes in body size of Pacific saury, catch and catch per unit effort were examined to investigate the environmental effects on the stock structure and abundance in the Tsushima Warm Current region. Interannual changes in thermal conditions are responsible for the different occurrence (catch) rates of sized group of the fish. Changes in body size due to environmental variables lead the stock to be homogeneous during the period of high abundance, while one of the reminder cohorts supports the stock during the period of low level of abundance. Migration circuits of two cohorts of saury stock are hypothesized on the basis of short life span and spatio-temporal changes of the stock structure in normal environmental conditions. Changes in upper ocean structure and production cycles by the decadal scale climate changes lead changes in stock structure and recruitment, resulting in the fluctuation of saury abundance. Hypothesized mechanism of the effects of climate changes on stock structure and abundance is illustrated on the basis of changes in thermal regime and production cycle.

Effect of environmental conditions on the stock structure and abundance of the pacific saury, Cololabis saira in the Tsushima Warm Current region

  • Gong, Yeong;Suh, Young-Sang;Hur, Young-Hee
    • Proceedings of the Korean Aquaculture Society Conference
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    • 2004.05a
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    • pp.169-171
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    • 2004
  • Interannual and decadal scale body size of Pacific saury, catch and catch per unit effort were examined to investigate the environmental effects on the stock structure and abundance in the Tsushima Warm Current region. Interannual changes in thermal conditions are responsible for the different occurrence (catch) rates of sized group of the fish. Changes in body size due to environmental variables lead the stock to be homogeneous during the period of high abundance, while one of the reminder cohorts supports the stock during the period of low level of abundance. Migration circuits of two cohorts of saury stock are hypothesized on the basis of short life span and spatio-temporal changes in stock structure in normal environmental conditions. Changes in upper ocean structure and production cycles by the decadal scale climate changes lead changes in stock structure and recruitment, resulting in the fluctuation of saury abundance. Hypothesized mechanism of the effects of climate changes on the stock structure and abundance is illustrated on the basis of changes in thermal regime and production cycle.

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Propagation of Engineering Changes for Supporting Consistent Product Data View (일관된 제품자료관점을 지원하는 설계변경 전달에 관한 연구)

  • 도남철
    • Korean Journal of Computational Design and Engineering
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    • v.8 no.2
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    • pp.90-100
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    • 2003
  • Engineering change (EC) objects are the data structure and related operations that can support applications for EC procedures or processes. Their functionalities include controlling management data, specifying related product structure, and archiving a history of product structure changes for EC management. In this paper we introduce a systematic approach to support the propagation of changes between different product structure views using the history of structure changes in EC objects. The change propagations supported by EC objects enable designers to maintain the consistency of multiple product structure views for engineering, manufacturing or even customer support applications. This paper also includes EC examples and experimental implementations for the proposed EC objects.

Comparison of accuracy between LC model and 4-PFM when COVID-19 impacts mortality structure

  • Choi, Janghoon
    • Communications for Statistical Applications and Methods
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    • v.28 no.3
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    • pp.233-250
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    • 2021
  • This paper studies if the accuracies of mortality models (LC model vs. 4-parametric model) are aggravated if a mortality structure changes due to the impact of COVID-19. LC model (LCM) uses dimension reduction for fitting to the log mortality matrix so that the performance of the dimension reduction method may not be good when the matrix structure changes. On the other hand, 4-parametric factor model (4-PFM) is designed to use factors for fitting to log mortality data by age groups so that it would be less affected by the change of the mortality structure. In fact, the forecast accuracies of LCM are better than those of 4-PFM when life-tables are used whereas those of 4-PFM are better when the mortality structure changes. Thus this result shows that 4-PFM is more reliable in performance to the structural changes of the mortality. To support the accuracy changes of LCM the functional aspect is explained by computing eigenvalues produced by singular vector decomposition

Feedback scope for fault detection and localization

  • Hunsang Jung;Park, Youngjin
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.32.6-32
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    • 2002
  • The damage localization of the structural system using the natural frequency measurement only is proposed. The existing methods use the changes of mode shape, strain mode shape or curvature mode shape before and after the damage occurrence as these shapes carry the geometric information of the structure. Basically, the change of natural frequencies of the structure can be used as the indicator of the damage occurrence but not as the indicator of the damage location as the natural frequency changes does not carry the geometric information of the structure. In this research, the feedback scope method that measures the natural frequency changes of the structure with and without the feedback Ioo...

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A Study on the Demand and Supply of Housing due to Population and Changes in Household - On the Social Causes of the Changes in the Population Structure in the Center - (인구구조와 가구 변화에 따른 주택공급 및 수요에 관한 연구 - 인구구조 변화의 사회적 원인을 중심으로 -)

  • Jung, Young-Soo;Lee, Jong-Kuk
    • Journal of the Korean housing association
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    • v.25 no.3
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    • pp.123-130
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    • 2014
  • The decrease in the birth rate of the modern changes in population structure changed recovery households and household members. This change was seen in the furniture sector, 2010 population housing total survey data according to the types of households and household members indicate that future changes. Problems can predict the various issues raised, and to ensure that the supply of housing of the population structure and household type is not done properly and home sales take a look at home since 2000, was popular during the 2010 State. Therefore, this study is suggesting workarounds necessary adjustments due to changes in population structure, analyze news coverage of members of households with housing demand and housing as a base quantity change in the future of furniture and home situation changes, including housing demand and supply to purpose. Specify the range of Daegu-City research studies range, national statistical data and related literature, comparative analysis of time trends and derive a conclusion.

A Study on the Valuation of Real Estate Using the Applies Real Option Model Considering Population Structure Changes (실물옵션 기법을 응용한 부동산 가치평가 연구: 인구구조 변화를 고려하여)

  • Gu, Seung Hwan;Ping, Wang;Jang, Seong Yong
    • Korean Management Science Review
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    • v.31 no.1
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    • pp.17-26
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    • 2014
  • This study presents a new real estate value analysis model considering the changes in the population structure. We propose a new model that takes advantage of the binomial option model one of the techniques of real options and considers the changes in the population structure. The real estate market price data of Seoul city from year 2001 to 2012 were extracted and the correlation analysis between real estate prices and changes in the population structure was performed. The result shows that they have positive correlation with one year time lag. The coefficient between the real estate prices and demographic changes was estimated using the OLS analysis and included in the traditional binomial option model to calculate the value of the property. It is assumed for the future price prediction that real estate invested in Seoul in January, 2013 will be sold within five years. Analysis result shows that the values of real estate in September of 2013 were predicted as 583.5 million won in the new model and as 582.4 million won in the traditional model. This reflects that the new model considering the change of population change gives better realistic performance than the traditional one.

Maritime Business Cycles with Multiple Structure Changes

  • Kim, Hyunsok
    • Journal of Navigation and Port Research
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    • v.44 no.5
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    • pp.407-413
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    • 2020
  • In this paper we examined a novel extension of the convergence empirics for the maritime business cycle which considers structure breaks and/or changes. To provide theoretical justification, the convergence hypothesis uses the relaxed assumption to technology shocks. Based on the recent empirical results provided by Kim and Chang (2020), we consider nonlinear dynamics that capture the properties on structural changes in the equilibrium adjustment process. This approach bridges the gap between the theoretical framework and empirical specifications. In particular, we applied the convergence hypothesis to the multiple structure change model for the maritime business cycle. Our application to the maritime data showed support of the convergence hypothesis allowing multiple structure changes during the high volatile period and offers additional insight into the forecasting maritime business cycles.

About the Influence of the Molecular Structure of selected classes of small molecules on their thermal behavior

  • Richter, Andreas M.;Lischewski, Volker;Felicetti, M.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.812-815
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    • 2004
  • The molecular structure influences the thermal behavior of HTM. For OLED the glass transition temperature and evaporation temperature are critical. We report how changes in structure cause changes on both parameters. The results may be of interest for chemists when they design new molecule structures for OLED.

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Development of an Overseas Real Estate Valuation Model Considering Changes in Population Structure

  • Gu, Seung-Hwan;Kim, Doo-Suk;Ping, Wang;Jang, Seong-Yong
    • Journal of Distribution Science
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    • v.12 no.3
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    • pp.65-73
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    • 2014
  • Purpose - Aging and fewer economically active people have challenged the assumption of continuous population increases. A new real estate valuation methodology reflecting changes in population structure is thus needed. Research design, data, and methodology - The relationship between demographic change and changes in real estate prices is analyzed using ordinary least squares (OLS) to estimate the parameters, and a population structure change (PSC)-Binomial Option Model is developed to assess the volatility of the estimated parameters. Results based on Seoul and Shanghai data are compared. Results - Results of the DCF method indicate that investing in Seoul is better than investing in Shanghai, but the binomial option indicates the opposite. The PSC-binomial option model, reflecting changes in population structure, yields higher values (24.6 million won in Seoul and 43.3 million won in Shanghai) than those given by the binomial option model. Conclusions - This study indicates that applying changes in population structure to existing research, such as in the binomial option model, represents a more accurate real estate valuation method. Results demonstrate that the new model is more accurate than existing models such as the DCF or binomial option.