• Title/Summary/Keyword: dynamic growth model

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Dynamic Growth Model for Pinus densiflora Stands in Anmyun-Island (안면도(安眠島) 소나무 임분(林分)의 동적(動的) 생장(生長)모델)

  • Seo, Jeong-Ho;Lee, Woo-Kyun;Son, Yowhan;Ham, Bo-Young
    • Journal of Korean Society of Forest Science
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    • v.90 no.6
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    • pp.725-733
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    • 2001
  • In this study, the relationship between growth factors for Pinus densiflora stands in Anmyun-Island was analyzed and dynamic growth model was prepared. A total of 96 sample plots was investigated in which dbh and height of individual trees were measured. From these plot data, quadratic mean dbh, mean height, dominant tree height, stem number per ha, basal area per ha and volume per ha were estimated. Several regression equations between growth factors were derived using NLIN and REG procedure of SAS. And dynamic growth model, in which the equations were interactively linked, was prepared for the prediction of stand growth and yield under different management regime. The predictions of dynamic growth model were found to be coincided with general growth principles. The dynamic growth model was considered as adequate for predicting growth and yield of Pinus densiflora stand in Anmyun-Island. In practice, the dynamic growth model can be applied for predicting the growth and development of stand for various forest treatments and for decision-making in forest management.

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A Physically Based Dynamic Recrystallization Model for Predicting High Temperature Flow Stress (열간 유동응력 예측을 위한 물리식 기반 동적 재결정 모델)

  • Lee, H.W.;Kang, S.H.;Lee, Y.S.
    • Transactions of Materials Processing
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    • v.22 no.8
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    • pp.450-455
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    • 2013
  • In the current study, a new dynamic recrystallization model for predicting high temperature flow stress is developed based on a physical model and the mean field theory. In the model, the grain aggregate is assumed as a representative volume element to describe dynamic recrystallization. The flow stress and microstructure during dynamic recrystallization were calculated using three sub-models for work hardening, for nucleation and for growth. In the case of work hardening, a single parameter dislocation density model was used to calculate change of dislocation density and stress in the grains. For modeling nucleation, the nucleation criterion developed was based on the grain boundary bulge mechanism and a constant nucleation rate was assumed. Conventional rate theory was used for describing growth. The flow stress behavior of pure copper was investigated using the model and compared with experimental findings. Simulated results by cellular automata were used for validating the model.

A Dynamic Analysis on Value Chain Model of E-Commerce - The Case of Online Book Market - (전자상거래의 가치사슬모형에 관한 동태적 분석 - 온라인 서점시장을 중심으로 -)

  • Lee Young-Chan;Seo Chang-Gab
    • Proceedings of the Korea Association of Information Systems Conference
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    • 2004.05a
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    • pp.316-335
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    • 2004
  • This paper builds a system dynamics model analyzing first mover effect and growth strategy of online retailer, a major segment of B2C e-commerce. The dynamic model in this paper is calibrated to the online book market and Yes24.com as major test cases. The model consists of eight key value chain sectors. Five of these(Users, Site Operations, Human Resources, Financial Accounting, and Fundraising) are internal to the company, and three others(Market, Financial Market, and Relative Performance) are external to the company. With the model, this paper suggests research propositions representing positive feedback loops and negative feedback loops that lead to corporate growth and limits to growth according to dynamic causal relationships among eight key value chain sectors, and simulate these propositions.

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The Dynamic Relationship of Domestic Credit and Stock Market Liquidity on the Economic Growth of the Philippines

  • CAMBA, Abraham C. Jr.;CAMBA, Aileen L.
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.1
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    • pp.37-46
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    • 2020
  • The paper examines the dynamic relationship of domestic credit and stock market liquidity on the economic growth of the Philippines from 1995 to 2018 applying the autoregressive distributed lag (ARDL) bounds testing approach to cointegration, together with Granger causality test based on vector error correction model (VECM). The ARDL model indicated a long-run relationship of domestic credit and stock market liquidity on GDP growth. When the GDP per capita is the dependent variable there is weak cointegration. Also, the Johansen cointegration test confirmed the existence of long-run relationship of domestic credit and stock market liquidity both on GDP growth and GDP per capita. The VECM concludes a long-run causality running from domestic credit and stock market liquidity to GDP growth. At levels, domestic credit has significant short-run causal relationship with GDP growth. As for stock market liquidity at first lag, has significant short-run causal relationship with GDP growth. With regards to VECM for GDP per capita, domestic credit and stock market liquidity indicates no significant dynamic adjustment to a new equilibrium if a disturbance occurs in the whole system. At levels, the results indicated the presence of short-run causality from stock market liquidity and GDP per capita. The CUSUMSQ plot complements the findings of the CUSUM plot that the estimated models for GDP growth and GDP per capita were stable.

The Effect of High-Skilled Emigration, Foreign Direct Investment, and Policy on the Growth Rate of Source Countries: A Panel Analysis

  • Kim, Jisong;Lee, Nah Youn
    • East Asian Economic Review
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    • v.20 no.2
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    • pp.229-275
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    • 2016
  • We study the effect of the high-skilled emigration rate on the growth rate of the source countries. We incorporate the foreign direct investment and the policy variables into the panel model and also their interactions with the high-skilled emigration rate, as they are related to the network externality that may be created by the high-skilled emigrants working abroad. We apply the static fixed-effects model and compare it with the results obtained in the dynamic panel model with system generalized methods of moments estimators. We find the negative effect of the high-skilled emigration rate by itself and in its interaction with the foreign direct investment only in the dynamic model. However, we find positive coefficient for the interaction of the high-skilled emigration rate and the civil liberties index, which holds across the static and dynamic specifications. This implies that the effect of the high-skilled emigration rate on the growth rate of the source countries can be positive, and the extent is larger for countries with 'poor' civil liberties. The developing countries with low levels of foreign direct investment inflows and 'poor' civil liberties can best benefit from the high levels of skilled emigration outward. Through finding significant interactions with other variables, we confirm that the high-skilled emigration should be considered along with other related variables in measuring its impact on growth. The implications offer suggestions for the international trade and aid policies.

Developing Dynamic DBH Growth Prediction Model by Thinning Intensity and Cycle - Based on Yield Table Data - (간벌강도 및 주기에 따른 동적 흉고직경 생장예측 모형개발 - 기존 수확표 자료를 기반으로 -)

  • Kim, Moonil;Lee, Woo-Kyun;Park, Taejin;Kwak, Hanbin;Byun, Jungyeon;Nam, Kijun;Lee, Kyung-Hak;Son, Yung-Mo;Won, Hyung-Kyu;Lee, Sang-Min
    • Journal of Korean Society of Forest Science
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    • v.101 no.2
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    • pp.266-278
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    • 2012
  • The objective of this study was developing dynamic stand growth model to predict diameter at breast height (DBH) growth by thinning intensity and cycle for major tree species of South Korea. The yield table, one of static stand growth models, constructed by Korea Forest Service was employed to prepare dynamic stand growth models for 8 tree species. In the process of model development, the thinning type was designated to thinning from below and equations for predicting the DBH change after thinning by different intensities was generated. In addition, stand density (N/ha), age and site index were adopted as explanatory variables for DBH prediction model. Thereafter, using the model, DBH growth under various silvicuture through integrating such equations considering thinning intensities, and cycles. The dynamic stand growth model of DBH developed in this study can provide understanding of effectiveness in forest growth and growing stock when thinning practice is performed in forest. Furthermore, results of this study is also applicable to quantitatively assess the carbon storage sequestration capability.

Inclusive Growth and Innovation: A Dynamic Simultaneous Equations Model on a Panel of Countries

  • Bresson, Georges;Etienne, Jean-Michel;Mohnen, Pierre
    • STI Policy Review
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    • v.6 no.1
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    • pp.1-23
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    • 2015
  • Based on the work of Anand et al. (2013) we measure inclusive income growth, which combines growth in gross domestic product (GDP) per capita and growth in the equity of the income distribution. Extending the work of Causa et al. (2014), we estimate a dynamic simultaneous structural equations model of GDP per capita and inclusive income on panel data for 63 countries over the 1990-2013 period. We estimate both equations in error correction form by difference GMM (generalized method of moments). Among the explanatory variables of the level and the distribution of GDP per capita we include R&D (research and development) expenditure per capita. In OECD countries we obtain a large positive effect of R&D on GDP. R&D is found to have a positive effect on the social mobility index but its impact on the income equity index at first decreases, then switches around to become slightly positive in the long run. In non- OECD countries, R&D is found to decrease inclusive income, mostly through a negative growth effect but also because of a slightly increasing income inequity effect.

Application of Dynamic Model SIMRIW for Predicting the Growth and Yield of Rice (수도성장 및 수량예측을 위한 동적모형 SIMRIW의 적용)

  • 이남호
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.35 no.2
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    • pp.73-80
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    • 1993
  • A simplified physiologically-based dynamic model, SIMRIW was selected for predicting the growth and yield of rice. The applicability of the model to the rice cultivars and weather conditions in the Republic of Korea was evaluated. Parameters of the model were calibrated using actual rice yields in Suweon region and an optimization scheme, Constrained Rosenbrock Algorithm. The simulated results from the calibrated model were in good agreement with the field data. The model with parameters calibrated for Suweon was applied to other five regions for the evaluation of transferability, but the simulated results fell short of satisfaction. However, the model is found to be applied to real-time prediction of the growth and yield of rice crop, which is believed to be useful for timely rice crop management, agricultural policy making, and optimal irrigation water management.

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A Study on the Dynamic Relationship between Cultural Industry and Economic Growth

  • He, Yugang
    • The Journal of Asian Finance, Economics and Business
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    • v.5 no.4
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    • pp.85-94
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    • 2018
  • The cultural industry is treated as the sunrise industry in modern society. It has taken an increasing role in promoting the economic growth. Due to this, this paper attempts to explore the dynamic relationship between cultural industry and the economic growth. On the grounds of Cobb-Douglas production function, the cultural industry is regarded as a determinant such as the labor input and the capital input to impact the economic growth. Meanwhile, the quarterly datum form 2000-Q1 to 2017-Q4 are employed to perform an empirical analysis via the vector error correction model. The GDP is treated as an independent variable. The input of capital, the input of labor and the total input of cultural industry are treated as dependent variables. Furthermore, a menu of statistical approaches such as the co-integration test and the impulse response function will be used to testify the dynamic relationship between cultural industry and economic growth. Via the Johansen co-integration test, the results report that the cultural industry has a obviously positive effect on economic growth. Through the vector error correction estimation, the results also report that the cultural industry also has a significantly positive effect on economic growth, but less than that of the Johansen co-integration test. This paper provides a view that the cultural industry is a kind of a determinant to promote the economic growth. Therefore, the China's government should pay much attention to the cultural industry construction.

Determinants of Economic Growth in Indonesia: A Dynamic Panel Model

  • BASUKI, Agus Tri;PURWANINGSIH, Yunastiti;SOESILO, Albertus Maqnus;MULYANTO, Mulyanto
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.11
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    • pp.147-156
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    • 2020
  • This study aims to analyze the effect of public spending, macroeconomic variables, and BPK opinion on economic growth. This study is motivated by the inequality of fiscal policy effectiveness between regions in Indonesia in influencing the economic growth of different regions, the ability of local governments to attract foreign investors, and the transparency of regional financial management in designing development programs to encourage regional economic growth. The analytical tool in this study is a dynamic panel regression model with data from 2008 to 2017. The results of this study show that, in the short term, the population affects regional economic growth, while in the long term, the economic growth is affected by the number of people, the poor, General Allocation Fund, health budget, foreign investment and BPK opinion. The findings of this study are that in the long term the General Allocation Fund becomes an obstacle to economic growth, this is because the general allocation funds is widely used to cover the lack of funds for routine regional activities, thereby reducing activities for development programs. Another research finding is that fiscal policies carried out by local governments make a small and ineffective contribution to promoting economic growth.