• Journal of Aerospace System Engineering
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• v.13 no.5
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• pp.94-101
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• 2019

The dynamic characteristics of the composite reflector panels are numerically and experimentally investigated. A dynamics model of the panel is analytically developed based on a deployment mechanism of the antenna. The deployment is passively activated using elastic energy of a spring with two rotational degrees of freedom. Using the flexible multi-body dynamic analysis ADAMS, dynamic behavior of the panels such as velocities, deformations, as well as reaction forces during the deployment, are investigated in the gravity and zero-gravity cases. The reflector panel is manufactured using carbon fiber reinforced plastics (CFRPs) and its deployment characteristics are experimentally observed using a zero-gravity deployment test. The impact response and vibration problems that occur during deployment of the antenna panel have been identified and reliably deployed using dampers.

• Journal of Navigation and Port Research
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• v.40 no.6
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• pp.485-494
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• 2016

The primary purpose of this study is to analyze the impact and determinants of bilateral Free Trade Agreements on international total bulk shipment trade volume at the port of Korea using the Panel Gravity Model. The model estimates the aggregated panel data of exports and imports (excluding transshipment) as a dependent variable during the period from 1996 to 2015. GDP, GDP per capita, distances between bilateral countries, and FTA dummies are included as independent variables. And the economic integration of FTAs including ASEAN+3 and NAFTA3 countries were used as dummy variables. Study results show that GDP and GDP per capita have positive impacts on bulk shipment trade volume at the port of Korea. In addition, Korea's bilateral FTAs with Singapore, India and the United States have positive effects on total bulk trade volume in Korea. This is the so called trade creation effect. On the other hand, ASEAN+3 and NAFTA have negative effects on the total bulk trade. This is the so called trade diversion effect. Also, the distance between Korea and its trade partners has a negative impact. These findings provide insights for: further academic research, site operators who work in related trade and maritime sectors, and policy makers engaged in port and maritime operations. The results can be used to develop strategies for maximizing bulk port throughput.

• Korea Trade Review
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• v.46 no.3
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• pp.1-24
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• 2021

The Belt and Road Initiative (BRI) is designed to intensify bilateral trade between China and the BRI countries through the improvement of transportation connections. However, little research has empirically investigated the impacts of this policies on the trade patterns. This paper attempts to evaluate the impacts of BRI on the trade patterns of Tanzania. Our study extends the original gravity model of bilateral trade by adding GDP per capita, population and proximity as the explanatory variables. According to our research, we observed that the BRI significantly impacted the Tanzania's trade patterns, as it led to the increase of bilateral trade flow between Tanzania and China more importantly between Tanzania and its adjacent countries. It indicates that the Belt and Road Initiative (BRI) has boosted Tanzania's trade exclusively, hence the Tanzania's export sector earns greater trading potential with the adjacent countries.

• International Area Studies Review
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• v.22 no.2
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• pp.3-18
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• 2018

This paper analyzes both the FTA effects and FTA spillover effects on bilateral trade using 62 countries' panel data during the period of 2003 ~ 2013. To this end, we construct a FTA dummy variable for the effect of FTA in the model and the weighted FTA matrix interacted with export and import for the spillover effect of FTA. Gravity model is applied to the empirical analysis with GMM, fixed and random effects, and PPML estimation. As a result of the analysis, FTA variables have positive relationships with bilateral export and import. The weighted FTA matrix interacted with export and import also have positive signs on the bilateral export and import in all estimations. Thus, we conclude that various FTAs of neighbor or 3rd countries increase the bilateral export and import. We provide some implications that a country to increase the amount of trade has a trade relationship with the countries having various FTAs and for the FTA effect analysis, the three-country model is better than to the two-country model.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.439-444
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• 2003

The response of a 1:5 scale 3-story masonry-infilled RC frame which was designed only for gravity loads were simulated by using a nonlinear analysis program, RUAUMOKO 2D. The objective of this study is to understand behavior of masonry-infilled panel and to verify the correlation between the experimental and analytical responses of a masonry-infilled RC frame. It is concluded from this comparison that the strength, stiffness and local behavior of the structure can be predicted with some reliability using this macro-model.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.657-664
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• 2020

We investigate the impact of roads and highways within the provinces on the regional trade of China using the augmented Gravity Model and theory of modeling trade. We take a panel data covering 31 provinces of China over 20 years period (1998-2017) for the estimations. We apply ARMA-OLS model, fixed and random effects, and robust findings by Hausman test. The results imply that road and highway lengths within the provinces have a significantly positive impact on the value of the province-wise exports. The positive impact is due to the fact the increased coverage of roads and highways increase accessibility to resources and mobility of goods and services within the regions. Moreover, employment in the transportation sector, per capita GDP and population of the provinces also illustrate positive and significant influence on regional exports and trade. The impact of China's WTO accession on regional exports has been positive, while the financial crisis has had a negative impact. The year dummies show that, in the years following the financial crisis, China was able to regress from the external shock as trade within the provinces increased. The increase in exports after financial crisis is mainly due to the government policies and support to every province.

• Journal of Technology Innovation
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• v.27 no.2
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• pp.99-122
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• 2019

ODA (Official Development Assistance) aims for practicing international humanitarianism in developing countries. However, ODA donors also seek to find convincing evidence meeting the national economic & political interests in the international community. In this regards, precise & unbiased estimation of the policy effects of ODA aid on the donors' exports to the recipient countries has recently become one of the primary concerns of the ODA donors, especially developing countries including Korea of which economy structure heavily relies on exports for economic growth. Based on the basic gravity model, this study empirically analyzes the effects of technical cooperation ODA delivering skills, knowledge and technical know-how on Korea's exports to the ODA recipient countries using 10-year panel data from 2007 to 2016. Specifically, by incorporating major variables affecting trade such as GDP, distance, FDI etc, the effect of technical cooperation ODA on Korea's exports to the ODA recipient countries is estimated with various kinds of panel models. As a result, technical cooperation ODA has a statistically significant impact on Korea's exports to ODA recipient countries, especially in the exports of intermediate goods. And the detail process of this black-boxed mechanism is scrutinized through case studies on Uzbekistan, The Philippines, and Morocco.

• Steel and Composite Structures
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• v.43 no.3
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• pp.327-340
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• 2022

A vast amount of experimental and analytical research has been conducted related to the seismic behavior and performance of concrete filled steel tubular (CFT) columns. This research has resulted in a wealth of information on the component behavior. However, analytical and experimental data for structural systems with CFT columns is limited, and the well-known behavior of steel or concrete structures is assumed valid for designing these systems. This paper presents the development of an analytical model for nonlinear analysis of composite moment resisting frame (CFT-MRF) systems with CFT columns and steel wide-flange (WF) beams under seismic loading. The model integrates component models for steel WF beams, CFT columns, connections between CFT columns and WF beams, and CFT panel zones. These component models account for nonlinear behavior due to steel yielding and local buckling in the beams and columns, concrete cracking and crushing in the columns, and yielding of panel zones and connections. Component tests were used to validate the component models. The model for a CFT-MRF considers second order geometric effects from the gravity load bearing system using a lean-on column. The experimental results from the testing of a four-story CFT-MRF test structure are used as a benchmark to validate the modeling procedure. An analytical model of the test structure was created using the modeling procedure and imposed-displacement analyses were used to reproduce the tests with the analytical model of the test structure. Good agreement was found at the global and local level. The model reproduced reasonably well the story shear-story drift response as well as the column, beam and connection moment-rotation response, but overpredicted the inelastic deformation of the panel zone.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.641-648
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• 2007

Computational rotor dynamic analyses of designed composite roller for large LCD panel manufacturing process have been conducted. The present computational method is based on the general finite element method with rotating gyroscopic effects. General purpose commercial finite element code, with special rotordynamics analysis module is applied. For the purpose of numerical verification, comparison study for a benchmark dual rotor model with support bearings is also presented. Detailed finite element models for composite roller with different length are constructed and analyzed considering gravity effect in order to investigate vibration characteristics in actual operation environment. As results of the present study, rotor stability diagrams and mass unbalance responses are presented for different rotating conditions.

• Journal of Korea Trade
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• v.24 no.5
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• pp.1-17
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• 2020

Purpose - This paper tries to estimate the effects of China's and Japan's free trade agreement (FTA) by panel generalized least squares (GLS). Design/methodology - The GLS model includes the basic gravity theory and Difference in Difference (DD) method to divide FTA conclusion countries and non-FTA conclusion countries with China and Japan. In order to empirically research the difference between Chinese and Japanese FTAs, we use the Difference in Difference in Difference (DDD) method. Findings - This paper finds the distance variable has more influence on Japanese than Chinese trade. The exchange rate indicates that Chinese trade depends on export and Japanese trade has the structure of re-import; shows that the countries that concluded FTAs with China and Japan have more positive trade effects than those that did not; finds the Chinese FTA promotion effects greater than the Japanese FTA because China had pushed ahead with trade policy since joining the WTO in 2001. Originality/value - This study shows that a single country's FTA and trade policies are an important factor concerning not just the promotion of trade but also the issue of trade conflicts.